More stories

  • in

    Standardized multi-omics of Earth’s microbiomes reveals microbial and metabolite diversity

    Dataset descriptionSample collectionOur research complies with all relevant ethical regulations following policies at the University of California, San Diego (UCSD). Animal samples that were sequenced were not collected at UCSD and are not for vertebrate animals research at UCSD following the UCSD Institutional Animal Care and Use Committee (IACUC). Samples were contributed by 34 principal investigators of the Earth Microbiome Project 500 (EMP500) Consortium and are samples from studies at their respective institutions (Supplementary Table 1). Relevant permits and ethics information for each parent study are described in the ‘Permits for sample collection’ section below. Samples were contributed as distinct sets referred to here as studies, where each study represented a single environment (for example, terrestrial plant detritus). To achieve more even coverage across microbial environments, we devised an ontology of sample types (microbial environments), the EMP Ontology (EMPO) (http://earthmicrobiome.org/protocols-and-standards/empo/)1, and selected samples to fill out EMPO categories as broadly as possible. EMPO recognizes strong gradients structuring microbial communities globally, and thus classifies microbial environments (level 4) on the basis of host association (level 1), salinity (level 2), host kingdom (if host-associated) or phase (if free-living) (level 3) (Fig. 1a). As we anticipated previously1, we have updated the number of levels as well as states therein for EMPO (Fig. 1b) on the basis of an important additional salinity gradient observed among host-associated samples when considering the previously unreported shotgun metagenomic and metabolomic data generated here (Fig. 3c,d). We note that although we were able to acquire samples for all EMPO categories, some categories are represented by a single study.Samples were collected following the Earth Microbiome Project sample submission guide50. Briefly, samples were collected fresh, split into 10 aliquots and then frozen, or alternatively collected and frozen, and subsequently split into 10 aliquots with minimal perturbation. Aliquot size was sufficient to yield 10–100 ng genomic DNA (approximately 107–108 cells). To leave samples amenable to chemical characterization (metabolomics), buffers or solutions for sample preservation (for example, RNAlater) were avoided. Ethanol (50–95%) was allowed as it is compatible with LC–MS/MS although it should also be avoided if possible.Sampling guidance was tailored for four general sample types: bulk unaltered (for example, soil, sediment, faeces), bulk fractionated (for example, sponges, corals, turbid water), swabs (for example, biofilms) and filters. Bulk unaltered samples were split fresh (or frozen), sampled into 10 pre-labelled 2 ml screw-cap bead beater tubes (Sarstedt, 72.694.005 or similar), ideally with at least 200 mg biomass, and flash frozen in liquid nitrogen (if possible). Bulk fractionated samples were fractionated as appropriate for the sample type, split into 10 pre-labelled 2 ml screw-cap bead beater tubes, ideally with at least 200 mg biomass, and flash frozen in liquid nitrogen (if possible). Swabs were collected as 10 replicate swabs using 5 BD SWUBE dual cotton swabs with wooden stick and screw cap (281130). Filters were collected as 10 replicate filters (47 mm diameter, 0.2 um pore size, polyethersulfone (preferred) or hydrophilic PTFE filters), placed in pre-labelled 2 ml screw-cap bead beater tubes, and flash frozen in liquid nitrogen (if possible). All sample types were stored at –80 °C if possible, otherwise –20 °C.To track the provenance of sample aliquots, we employed a QR coding scheme. Labels were affixed to aliquot tubes before shipping when possible. QR codes had the format ‘name.99.s003.a05’, where ‘name’ is the PI name, ‘99’ is the study ID, ‘s003’ is the sample number and ‘a05’ is the aliquot number. QR codes (version 2, 25 pixels × 25 pixels) were printed on 1.125’ × 0.75’ rectangular and 0.437’ circular cap Cryogenic Direct Thermal labels (GA International, DFP-70) using a Zebra model GK420d printer and ZebraDesigner Pro 3 software for Windows. After receipt but before aliquots were stored in freezers, QR codes were scanned into a sample inventory spreadsheet using a QR scanner.Sample metadataEnvironmental metadata were collected for all samples on the basis of the EMP Metadata Guide, which combines guidance from the Genomics Standards Consortium MIxS (Minimum Information about any Sequence) standard74 and the Qiita Database (https://qiita.ucsd.edu)51. The metadata guide provides templates and instructions for each MIxS environmental package (that is, sample type). Relevant information describing each PI submission, or study, was organized into a separate study metadata file (Supplementary Table 1).MetabolomicsLC–MS/MS sample extraction and preparationTo profile metabolites among all samples, we used LC–MS/MS, a versatile method that detects tens of thousands of metabolites in biological samples. All solvents and reactants used were LC–MS grade. To maximize the biomass extracted from each sample, the samples were prepared depending on their sampling method (for example, bulk, swabs, filter and controls). The bulk samples were transferred into a microcentrifuge tube (polypropylene, PP) and dissolved in 7:3 MeOH:H2O using a volume varying from 600 µl to 1.5 ml, depending on the amounts of sample available, and homogenized in a tissue lyser (QIAGEN) at 25 Hz for 5 min. Then, the tubes were centrifuged at 2,000 × g for 15 min, and the supernatant was collected in a 96-well plate (PP). For swabs, the swabs were transferred into a 96-well plate (PP) and dissolved in 1.0 ml of 9:1 ethanol:H2O. The prepared plates were sonicated for 30 min, and after 12 h at 4 °C, the swabs were removed from the wells. The filter samples were dissolved in 1.5 ml of 7:3 MeOH:H2O in microcentrifuge tubes (PP) and sonicated for 30 min. After 12 h at 4 °C, the filters were removed from the tubes. The tubes were centrifuged at 2,000 × g for 15 min, and the supernatants were transferred to 96-well plates (PP). The process control samples (bags, filters and tubes) were prepared by adding 3.0 ml of 2:8 MeOH:H2O and recovering 1.5 ml after 2 min. After the extraction process, all sample plates were dried with a vacuum concentrator and subjected to solid phase extraction (SPE). SPE was used to remove salts that could reduce ionization efficiency during mass spectrometry analysis, as well as the most polar and non-polar compounds (for example, waxes) that cannot be analysed efficiently by reversed-phase chromatography. The protocol was as follows: the samples (in plates) were dissolved in 300 µl of 7:3 MeOH:H2O and put in an ultrasound bath for 20 min. SPE was performed with SPE plates (Oasis HLB, hydrophilic-lipophilic-balance, 30 mg with particle sizes of 30 µm). The SPE beds were activated by priming them with 100% MeOH, and equilibrated with 100% H2O. The samples were loaded on the SPE beds, and 100% H2O was used as wash solvent (600 µl). The eluted washing solution was discarded, as it contains salts and very polar metabolites that subsequent metabolomics analysis is not designed for. The sample elution was carried out sequentially with 7:3 MeOH:H2O (600 µl) and 100% MeOH (600 µl). The obtained plates were dried with a vacuum concentrator. For mass spectrometry analysis, the samples were resuspended in 130 µl of 7:3 MeOH:H2O containing 0.2 µM of amitriptyline as an internal standard. The plates were centrifuged at 30 × g for 15 min at 4 °C. Samples (100 µl) were transferred into new 96-well plates (PP) for mass spectrometry analysis.LC–MS/MS sample analysisThe extracted samples were analysed by ultra-high performance liquid chromatography (UHPLC, Vanquish, Thermo Fisher) coupled to a quadrupole-Orbitrap mass spectrometer (Q Exactive, Thermo Fisher) operated in data-dependent acquisition mode (LC–MS/MS in DDA mode). Chromatographic separation was performed using a Kinetex C18 1.7 µm (Phenomenex), 100 Å pore size, 2.1 mm (internal diameter) × 50 mm (length) column with a C18 guard cartridge (Phenomenex). The column was maintained at 40 °C. The mobile phase was composed of a mixture of (A) water with 0.1% formic acid (v/v) and (B) acetonitrile with 0.1% formic acid. Chromatographic elution method was set as follows: 0.00–1.00 min, isocratic 5% B; 1.00–9.00 min, gradient from 5% to 100% B; 9.00–11.00 min, isocratic 100% B; followed by equilibration 11.00–11.50 min, gradient from 100% to 5% B; 11.50–12.50 min, isocratic 5% B. The flow rate was set to 0.5 ml min−1.The UHPLC was interfaced to the orbitrap using a heated electrospray ionization source with the following parameters: ionization mode, positive; spray voltage, +3,496.2 V; heater temperature, 363.90 °C; capillary temperature, 377.50 °C; S-lens RF, 60 arbitrary units (a.u.); sheath gas flow rate, 60.19 a.u.; and auxiliary gas flow rate, 20.00 a.u. The MS1 scans were acquired at a resolution (at m/z 200) of 35,000 in the m/z 100–1500 range, and the fragmentation spectra (MS2) scans at a resolution of 17,500 from 0 to 12.5 min. The automatic gain control target and maximum injection time were set at 1.0 × 106 and 160 ms for MS1 scans, and set at 5.0 × 105 and 220 ms for MS2 scans, respectively. Up to three MS2 scans in data-dependent mode (Top 3) were acquired for the most abundant ions per MS1 scans using the apex trigger mode (4–15 s), dynamic exclusion (11 s) and automatic isotope exclusion. The starting value for MS2 was m/z 50. Higher-energy collision induced dissociation (HCD) was performed with a normalized collision energy of 20, 30 and 40 eV in stepped mode. The major background ions originating from the SPE were excluded manually from the MS2 acquisition. Analyses were randomized within plate and blank samples analysed every 20 injections. A quality control mix sample assembled from 20 random samples across the sample types was injected at the beginning, the middle and the end of each plate sequence. The chromatographic shift observed throughout the batch was estimated as less than 2 s, and the relative standard deviation of ion intensity was 15% per replicate.LC–MS/MS data processingThe mass spectrometry data were centroided and converted from the proprietary format (.raw) to the m/z extensible markup language format (.mzML) using ProteoWizard (ver. 3.0.19, MSConvert tool)75. The mzML files were then processed with MZmine 2 toolbox76 using the ion-identity networking modules77 that allow advanced detection for adduct/isotopologue annotations. The MZmine processing was performed on Ubuntu 18.04 LTS 64-bits workstation (Intel Xeon E5-2637, 3.5 GHz, 8 cores, 64 Gb of RAM) and took ~3 d. The MZmine project, the MZmine batch file (.XML format) and results files (.MGF and .CSV) are available in the MassIVE dataset MSV000083475. The MZmine batch file contains all the parameters used during the processing. In brief, feature detection and deconvolution was performed with the ADAP chromatogram builder78 and local minimum search algorithm. The isotopologues were regrouped and the features (peaks) were aligned across samples. The aligned peak list was gap filled and only peaks with an associated fragmentation spectrum and occurring in a minimum of three files were conserved. Peak shape correlation analysis grouped peaks originating from the same molecule and annotated adduct/isotopologue with ion-identity networking77. Finally, the feature quantification table results (.CSV) and spectral information (.MGF) were exported with the GNPS module for feature-based molecular networking analysis on GNPS79 and with SIRIUS export modules.LC–MS/MS data annotationThe results files of MZmine (.MGF and .CSV files) were uploaded to GNPS (http://gnps.ucsd.edu)52 and analysed with the feature-based molecular networking workflow79. Spectral library matching was performed against public fragmentation spectra (MS2) spectral libraries on GNPS and the NIST17 library.For the additional annotation of small peptides, we used the DEREPLICATOR tools available on GNPS80,81. We then used SIRIUS82 (v. 4.4.25, headless, Linux) to systematically annotate the MS2 spectra. Molecular formulae were computed with the SIRIUS module by matching the experimental and predicted isotopic patterns83, and from fragmentation trees analysis84 of MS2. Molecular formula prediction was refined with the ZODIAC module using Gibbs sampling85 on the fragmentation spectra (chimeric spectra or those with poor fragmentation were excluded). In silico structure annotation using structures from biodatabase was done with CSI:FingerID86. Systematic class annotations were obtained with CANOPUS41 and used the NPClassifier ontology87.The parameters for SIRIUS tools were set as follows, for SIRIUS: molecular formula candidates retained, 80; molecular formula database, ALL; maximum precursor ion m/z computed, 750; profile, orbitrap; m/z maximum deviation, 10 ppm; ions annotated with MZmine were prioritized and other ions were considered (that is, [M+H3N+H]+, [M+H]+, [M+K]+, [M+Na]+, [M+H-H2O]+, [M+H-H4O2]+, [M+NH4]+); for ZODIAC: the features were split into 10 random subsets for lower computational burden and computed separately with the following parameters: threshold filter, 0.9; minimum local connections, 0; for CSI:FingerID: m/z maximum deviation, 10 ppm; and biological database, BIO.To establish putative microbially related secondary metabolites, we collected annotations from spectral library matching and the DEREPLICATOR+ tools and queried them against the largest microbial metabolite reference databases (Natural Products Atlas88 and MIBiG89). Molecular networking79 was then used to propagate the annotation of microbially related secondary metabolites throughout all molecular families (that is, the network component).LC–MS/MS data analysisWe combined the annotation results from the different tools described above to create a comprehensive metadata file describing each metabolite feature observed. Using that information, we generated a feature-table including only secondary metabolite features determined to be microbially related. We then excluded very low-intensity features introduced to certain samples during the gap-filling step described above. These features were identified on the basis of presence in negative controls that were universal to all sample types (that is, bulk, filter and swab) and by their relatively low per-sample intensity values. Finally, we excluded features present in positive controls for sampling devices specific to each sample type (that is, bulk, filter or swab). The final feature-table included 618 samples and 6,588 putative microbially related secondary metabolite features that were used for subsequent analysis.We used QIIME 2’s90 (v2020.6) ‘diversity’ plugin to quantify alpha-diversity (that is, feature richness) for each sample and ‘deicode’91 to quantify beta-diversity (that is, robust Aitchison distances, which are robust to both sparsity and compositionality in the data) between each pair of samples. We parameterized our robust Aitchison principal components analysis (RPCA)91 to exclude samples with fewer than 500 features and features present in fewer than 10% of samples. We used the ‘taxa’ plugin to quantify the relative abundance of microbially related secondary metabolite pathways and superclasses (that is, on the basis of NPClassifier) within each environment (that is, for each level of EMPO 4), and ‘songbird’ v1.0.492 to identify sets of microbially related secondary metabolites whose abundances were associated with certain environments. We parameterized our ‘songbird’ model as follows: epochs, 1,000,000; differential prior, 0.5; learning rate, 1.0 × 10−5; summary interval, 2; batch size, 400; minimum sample count, 0; and training on 80% of samples at each level of EMPO 4 using ‘Animal distal gut (non-saline)’ as the reference environment. Environments with fewer than 10 samples were excluded to optimize model training (that is, ‘Animal corpus (non-saline)’, ‘Animal proximal gut (non-saline)’, ‘Surface (saline)’). The output from ‘songbird’ includes a rank value for each metabolite in every environment, which represents the log fold change for a given metabolite in a given environment92. We compared log fold changes for each metabolite from this run to those from (1) a replicate run using the same reference environment and (2) a run using a distinct reference environment: ‘Water (saline)’. We found strong Spearman correlations in both cases (Supplementary Table 8), and therefore focused on results from the original run using ‘Animal distal gut (non-saline)’ as the reference environment, as it has previously been shown to be relatively unique among other habitats. In addition to summarizing the top 10 metabolites for each environment (Supplementary Table 3), we used the log fold change values in our multi-omics analyses described below.We used the RPCA biplot and QIIME 2’s90 EMPeror93 to visualize differences in composition among samples, as well as the association with samples of the 25 most influential microbially related secondary metabolite features (that is, those with the largest magnitude across the first three principal component loadings). We tested for significant differences in metabolite composition across all levels of EMPO using PERMANOVA implemented with QIIME 2’s ‘diversity’ plugin90 and using our robust Aitchison distance matrix as input. In parallel, we used the differential abundance results from ‘songbird’ described above to identify specific microbially related secondary metabolite pathways and superclasses that varied strongly across environments. We then went back to our metabolite feature-table to visualize differences in the relative abundances of those pathways and superclasses within each environment by first selecting features and calculating log-ratios using ‘qurro’94, and then plotting using the ‘ggplot2’ package95 in R96 v4.0.0. We tested for significant differences in relative abundances across environments using Kruskal–Wallis tests implemented with the base ‘stats’ package in R96.GC–MS sample extraction and preparationTo profile volatile small molecules among all samples in addition to what was captured with LC–MS/MS, we used gas chromatography coupled with mass spectrometry (GC–MS). All solvents and reactants were GC–MS grade. Two protocols were used for sample extraction, one for the 105 soil samples and a second for the 356 faecal and sediment samples that were treated as biosafety level 2. The 105 soil samples were received at the Pacific Northwest National Laboratory and processed as follows. Each soil sample (1 g) was weighed into microcentrifuge tubes (Biopur Safe-Lock, 2.0 ml, Eppendorf). H2O (1 ml) and one scoop (~0.5 g) of a 1:1 (v/v) mixture of garnet (0.15 mm, Omni International) and stainless steel (0.9–2.0 mm blend, Next Advance) beads and one 3 mm stainless steel bead (Qiagen) were added to each tube. Samples were homogenized in a tissue lyser (Qiagen) for 3 min at 30 Hz and transferred into 15 ml polypropylene tubes (Olympus, Genesee Scientific). Ice-cold water (1 ml) was used to rinse the smaller tube and combined into the 15 ml tube. Chloroform:methanol (10 ml, 2:1 v/v) was added and samples were rotated at 4 °C for 10 min, followed by cooling at −70 °C for 10 min and centrifuging at 150 × g for 10 min to separate phases. The top and bottom layers were combined into 40 ml glass vials and dried using a vacuum concentrator. Chloroform:methanol (1 ml, 2:1) was added to each large glass vial and the sample was transferred into 1.5 ml tubes and centrifuged at 1,300 × g. The supernatant was transferred into glass vials and dried for derivatization.The remaining 356 samples received from UCSD that included faecal and sediment samples were processed as follows: 100 µl of each sample was transferred to a 2 ml microcentrifuge tube using a scoop (MSP01, Next Advance). The final volume of the sample was brought to 1.5 ml, ensuring that the solvent ratio is 3:8:4 H2O:CHCl3:MeOH by adding the appropriate volumes of H2O, MeOH and CHCl3. After transfer, one 3 mm stainless steel bead (QIAGEN), 400 µl methanol and 300 µl H2O were added to each tube and the samples were vortexed for 30 s. Then, 800 µl chloroform was added and samples were vortexed for 30 s. After centrifuging at 150 × g for 10 min to separate phases, the top and bottom layers were combined in a vial and dried for derivatization.The samples were derivatized for GC–MS analysis as follows: 20 µl of a methoxyamine solution in pyridine (30 mg ml−1) was added to the sample vial and vortexed for 30 s. A bath sonicator was used to ensure that the sample was completely dissolved. Samples were incubated at 37 °C for 1.5 h while shaking at 1,000 r.p.m. N-methyl-N-trimethylsilyltrifluoroacetamide (80 µl) and 1% trimethylchlorosilane solution was added and samples were vortexed for 10 s, followed by incubation at 37 °C for 30 min, with 1,000 r.p.m. shaking. The samples were then transferred into a vial with an insert.An Agilent 7890A gas chromatograph coupled with a single quadrupole 5975C mass spectrometer (Agilent) and an HP-5MS column (30 m × 0.25 mm × 0.25 μm; Agilent) was used for untargeted analysis. Samples (1 μl) were injected in splitless mode, and the helium gas flow rate was determined by the Agilent Retention Time Locking function on the basis of analysis of deuterated myristic acid (Agilent). The injection port temperature was held at 250 °C throughout the analysis. The GC oven was held at 60 °C for 1 min after injection, and the temperature was then increased to 325 °C at a rate of 10 °C min−1, followed by a 10 min hold at 325 °C. Data were collected over the mass range of m/z 50–600. A mixture of FAMEs (C8–C28) was analysed each day with the samples for retention index alignment purposes during subsequent data analysis.GC–MS data processing and annotationThe data were converted from vendor’s format to the .mzML format and processed using GNPS GC–MS data analysis workflow (https://gnps.ucsd.edu)97. The compounds were identified by matching experimental spectra to the public libraries available at GNPS, as well as NIST 17 and Wiley libraries. The data are publicly available at the MassIVE depository (https://massive.ucsd.edu); dataset ID: MSV000083743. The GNPS deconvolution is available in GNPS (https://gnps.ucsd.edu/ProteoSAFe/status.jsp?task=d5c5135a59eb48779216615e8d5cb3ac), as is the library search (https://gnps.ucsd.edu/ProteoSAFe/status.jsp?task=59b20fc8381f4ee6b79d35034de81d86).GC–MS data analysisFor multi-omics analyses including GC–MS data, we first removed noisy (that is, suspected background contaminants and artifacts) features by excluding those with balance scores 1.5–2 kb DNA fragments’ (Oxford Nanopore Technologies). The resulting product consists of uniquely tagged rRNA operon amplicons. The uniquely tagged rRNA operons were amplified in a second PCR, where the reaction (100 µl) contained 2 U Platinum SuperFi DNA Polymerase High Fidelity (Thermo Fisher) and a final concentration of 1X SuperFi buffer, 0.2 mM of each dNTP, and 500 nM of each forward and reverse synthetic primer targeting the tailed primers from above. The PCR cycling parameters consisted of an initial denaturation (3 min at 95 °C) and then 25–35 cycles of denaturation (15 s at 95 °C), annealing (30 s at 60 °C) and extension (6 min at 72 °C), followed by final extension (5 min at 72 °C). The PCR product was purified using the custom bead purification protocol above. Batches of 25 amplicon libraries were barcoded and sent for PacBio Sequel II library preparation and sequencing (Sequel II SMRT Cell 8M and 30 h collection time) at the DNA Sequencing Center at Brigham Young University. Circular consensus sequencing (CCS) reads were generated using CCS v.3.4.1 (https://github.com/PacificBiosciences/ccs) using default settings. UMI consensus sequences were generated using the longread_umi pipeline (https://github.com/SorenKarst/longread_umi) with the following command: longread_umi pacbio_pipeline -d ccs_reads.fq -o out_dir -m 3500 -M 6000 -s 60 -e 60 -f CAAGCAGAAGACGGCATACGAGAT -F AGRGTTYGATYMTGGCTCAG -r AATGATACGGCGACCACCGAGATC -R CGACATCGAGGTGCCAAAC -U ‘0.75;1.5;2;0’ -c 2.Amplicon data analysisFor multi-omics analyses including amplicon sequence data, we processed each dataset for comparison of beta-diversity. For all amplicon data except that for bacterial full-length rRNA amplicons, raw sequence data were converted from bcl to fastq, and then multiplexed files for each sequencing run uploaded as separate preparations to Qiita (study: 13114).For each 16S sequencing run, in Qiita, data were demultiplexed, trimmed to 150 bp and denoised using Deblur122 to generate a feature-table of sub-operational taxonomic units (sOTUs) per sample, using default parameters. We then exported feature-tables and denoised sequences from each sequencing run, used QIIME 2’s ‘feature-table’ plugin to merge feature-tables and denoised reads across sequencing runs, and placed all denoised reads into the GreenGenes 13_8 phylogeny123 via fragment insertion using QIIME 2’s90 SATé-Enabled Phylogenetic Placement (SEPP)124 plugin to produce a phylogeny for diversity analyses. To allow for phylogenetically informed diversity analyses, reads not placed during SEPP (that is, 513 sOTUs, 0.1% of all sOTUs) were removed from the merged feature-table. We then used QIIME 2’s ‘feature-table’ plugin to exclude singleton sOTUs and rarefy the data to 5,000 reads per sample. Rarefaction depths for all amplicon analyses were chosen to best normalize sampling effort per sample while maintaining ≥75% of samples representative of Earth’s environments, and also to maintain consistency with the analyses from EMP release 1. We then used QIIME 2’s90 ‘diversity’ plugin to estimate alpha-diversity (that is, sOTU richness) and beta-diversity (that is, unweighted UniFrac distances). The final feature-table for 16S beta-diversity analysis included 681 samples and 93,260 features. We performed a comparative analysis of the data including and excluding the reads not placed during SEPP, and note that both alpha-diversity (that is, sOTU richness) and beta-diversity (that is, sample–sample RPCA distances) were highly correlated between datasets (Spearman r = 1.0) (Supplementary Fig. 5). We thus proceeded with the SEPP-filtered dataset and used phylogenetically informed diversity metrics where applicable.For 18S data, we used QIIME 2’s90 ‘demux’ plugin’s ‘emp-paired’ method125,126 to first demultiplex each sequencing run, and then the ‘cutadapt’ plugin’s127 ‘trim-paired’ method to trim sequencing primers from reads. We then exported trimmed reads, concatenated R1 and R2 read files per sample, and denoised reads using Deblur’s122,128 ‘workflow’ with default settings, trimming reads to 90 bp, and taking the ‘all.biom’ and ‘all.seqs’ output, for each sequencing run. We then used QIIME 2’s ‘feature-table’ plugin to merge feature-tables and denoised sequences across sequencing runs, and then the ‘feature-classifier’ plugin’s ‘classify-sklearn’ method to classify taxonomy for each sOTU via pre-fitted machine-learning classifiers129 and the SILVA 138 reference database130. We then used QIIME 2’s90 ‘feature-table’ plugin to exclude reads assigned to bacteria and archaea, singleton sOTUs and samples with a total frequency of More

  • in

    Soil organic matter formation and loss are mediated by root exudates in a temperate forest

    Keenan, T. F. & Williams, C. A. The terrestrial carbon sink. Annu. Rev. Environ. Resour. 43, 219–243 (2018).Article 

    Google Scholar 
    Terrer, C. et al. A trade-off between plant and soil carbon storage under elevated CO2. Nature 591, 599–603 (2021).Article 

    Google Scholar 
    Walker, A. P. et al. Integrating the evidence for a terrestrial carbon sink caused by increasing atmospheric CO2. N. Phytol. 229, 2413–2445 (2021).Article 

    Google Scholar 
    Fossum, C. et al. Belowground allocation and dynamics of recently fixed plant carbon in a California annual grassland. Soil Biol. Biochem. 165, 108519 (2022).Article 

    Google Scholar 
    Rasse, D. P., Rumpel, C. & Dignac, M.-F. Is soil carbon mostly root carbon? Mechanisms for a specific stabilisation. Plant Soil 269, 341–356 (2005).Article 

    Google Scholar 
    Sokol, N. W., Kuebbing, Sara, E., Karlsen-Ayala, E. & Bradford, M. A. Evidence for the primacy of living root inputs, not root or shoot litter, in forming soil organic carbon. N. Phytol. 221, 233–246 (2019).Article 

    Google Scholar 
    Calvo, O. C., Franzaring, J., Schmid, I. & Fangmeier, A. Root exudation of carbohydrates and cations from barley in response to drought and elevated CO2. Plant Soil 438, 127–142 (2019).Article 

    Google Scholar 
    Fransson, P. M. A. & Johansson, E. M. Elevated CO2 and nitrogen influence exudation of soluble organic compounds by ectomycorrhizal root systems. FEMS Microbiol. Ecol. 71, 186–196 (2009).Article 

    Google Scholar 
    Johansson, E. M., Fransson, P. M. A., Finlay, R. D. & van Hees, P. A. W. Quantitative analysis of soluble exudates produced by ectomycorrhizal roots as a response to ambient and elevated CO2. Soil Biol. Biochem. 41, 1111–1116 (2009).Article 

    Google Scholar 
    Phillips, R. P., Finzi, A. C. & Bernhardt, E. S. Enhanced root exudation induces microbial feedbacks to N cycling in a pine forest under long-term CO2 fumigation. Ecol. Lett. 14, 187–194 (2011).Article 

    Google Scholar 
    Jilling, A., Keiluweit, M., Gutknecht, J. L. M. & Grandy, A. S. Priming mechanisms providing plants and microbes access to mineral-associated organic matter. Soil Biol. Biochem. 158, 108265 (2021).Article 

    Google Scholar 
    Cotrufo, M. F., Wallenstein, M. D., Boot, C. M., Denef, K. & Paul, E. The Microbial Efficiency-Matrix Stabilization (MEMS) framework integrates plant litter decomposition with soil organic matter stabilization: do labile plant inputs form stable soil organic matter? Glob. Change Biol. 19, 988–995 (2013).Article 

    Google Scholar 
    Sokol, N. W., Sanderman, J. & Bradford, M. A. Pathways of mineral-associated soil organic matter formation: integrating the role of plant carbon source, chemistry, and point of entry. Glob. Change Biol. 25, 12–24 (2019).Article 

    Google Scholar 
    Bradford, M. A., Keiser, A. D., Davies, C. A., Mersmann, C. A. & Strickland, M. S. Empirical evidence that soil carbon formation from plant inputs is positively related to microbial growth. Biogeochemistry 113, 271–281 (2013).Article 

    Google Scholar 
    Keiluweit, M. et al. Mineral protection of soil carbon counteracted by root exudates. Nat. Clim. Change 5, 588–595 (2015).Article 

    Google Scholar 
    Kuzyakov, Y., Friedel, J. K. & Stahr, K. Review of mechanisms and quantification of priming effects. Soil Biol. Biochem. 32, 1485–1498 (2000).Article 

    Google Scholar 
    Jones, D. L., Dennis, P. G., Owen, A. G. & van Hees, P. A. W. Organic acid behavior in soils—misconceptions and knowledge gaps. Plant Soil 248, 31–41 (2003).Article 

    Google Scholar 
    Cleveland, C. C. & Liptzin, D. C:N:P stoichiometry in soil: is there a “Redfield ratio” for the microbial biomass? Biogeochemistry 85, 235–252 (2007).Article 

    Google Scholar 
    Meier, I. C., Finzi, A. C. & Phillips, R. P. Root exudates increase N availability by stimulating microbial turnover of fast-cycling N pools. Soil Biol. Biochem. 106, 119–128 (2017).Article 

    Google Scholar 
    Canarini, A., Kaiser, C., Merchant, A., Richter, A. & Wanek, W. Root exudation of primary metabolites: mechanisms and their roles in plant responses to environmental stimuli. Front. Plant Sci. 10, 157 (2019).Article 

    Google Scholar 
    Koo, B.-J., Adriano, D. C., Bolan, N. S. & Barton, C. D. in Encyclopedia of Soils in the Environment (ed. Hillel, D.) 421–428 (Elsevier, 2005); https://doi.org/10.1016/B0-12-348530-4/00461-6Oldfield, E. E., Crowther, T. W. & Bradford, M. A. Substrate identity and amount overwhelm temperature effects on soil carbon formation. Soil Biol. Biochem. 124, 218–226 (2018).Article 

    Google Scholar 
    Mason-Jones, K., Schmücker, N. & Kuzyakov, Y. Contrasting effects of organic and mineral nitrogen challenge the N-mining hypothesis for soil organic matter priming. Soil Biol. Biochem. 124, 38–46 (2018).Article 

    Google Scholar 
    Sokol, N. W. & Bradford, M. A. Microbial formation of stable soil carbon is more efficient from belowground than aboveground input. Nat. Geosci. 12, 46–53 (2019).Article 

    Google Scholar 
    Drake, J. E. et al. Stoichiometry constrains microbial response to root exudation—insights from a model and a field experiment in a temperate forest. Biogeosciences 10, 821–838 (2013).Article 

    Google Scholar 
    Falchini, L., Naumova, N., Kuikman, P. J., Bloem, J. & Nannipieri, P. CO2 evolution and denaturing gradient gel electrophoresis profiles of bacterial communities in soil following addition of low molecular weight substrates to simulate root exudation. Soil Biol. Biochem. 35, 775–782 (2003).Article 

    Google Scholar 
    Rasmussen, C., Southard, R. J. & Horwath, W. R. Soil mineralogy affects conifer forest soil carbon source utilization and microbial priming. Soil Sci. Soc. Am. J. 71, 1141–1150 (2007).Article 

    Google Scholar 
    Frey, S. D., Lee, J., Melillo, J. M. & Six, J. The temperature response of soil microbial efficiency and its feedback to climate. Nat. Clim. Change 3, 395–398 (2013).Article 

    Google Scholar 
    Angst, G., Mueller, K. E., Nierop, K. G. J. & Simpson, M. J. Plant- or microbial-derived? A review on the molecular composition of stabilized soil organic matter. Soil Biol. Biochem. 156, 108189 (2021).Article 

    Google Scholar 
    Craig, M. E. et al. Fast-decaying plant litter enhances soil carbon in temperate forests but not through microbial physiological traits. Nat. Commun. 13, 1229 (2022).Article 

    Google Scholar 
    Blagodatsky, S., Blagodatskaya, E., Yuyukina, T. & Kuzyakov, Y. Model of apparent and real priming effects: linking microbial activity with soil organic matter decomposition. Soil Biol. Biochem. 42, 1275–1283 (2010).Article 

    Google Scholar 
    Hill, P. W., Farrar, J. F. & Jones, D. L. Decoupling of microbial glucose uptake and mineralization in soil. Soil Biol. Biochem. 40, 616–624 (2008).Article 

    Google Scholar 
    Asmar, F., Eiland, F. & Nielsen, N. E. Interrelationship between extracellular enzyme activity, ATP content, total counts of bacteria and CO2 evolution. Biol. Fertil. Soils 14, 288–292 (1992).Article 

    Google Scholar 
    Fontaine, S., Mariotti, A. & Abbadie, L. The priming effect of organic matter: a question of microbial competition? Soil Biol. Biochem. 35, 837–843 (2003).Article 

    Google Scholar 
    McFarlane, K. J. et al. Comparison of soil organic matter dynamics at five temperate deciduous forests with physical fractionation and radiocarbon measurements. Biogeochemistry 112, 457–476 (2013).Article 

    Google Scholar 
    Post, W. M., Emanuel, W. R., Zinke, P. J. & Stangenberger, A. G. Soil carbon pools and world life zones. Nature 298, 156–159 (1982).Article 

    Google Scholar 
    Smith, W. H. Character and significance of forest tree root exudates. Ecology 57, 324–331 (1976).Article 

    Google Scholar 
    Dong, J. et al. Impacts of elevated CO2 on plant resistance to nutrient deficiency and toxic ions via root exudates: a review. Sci. Total Environ. 754, 142434 (2021).Article 

    Google Scholar 
    White, M. A., Running, S. W. & Thornton, P. E. The impact of growing-season length variability on carbon assimilation and evapotranspiration over 88 years in the eastern US deciduous forest. Int. J. Biometeorol. 42, 139–145 (1999).Article 

    Google Scholar 
    Giasson, M.-A. et al. Soil respiration in a northeastern US temperate forest: a 22-year synthesis. Ecosphere 4, 140 (2013).Article 

    Google Scholar 
    Mrak, T. et al. Elevated ozone prevents acquisition of available nitrogen due to smaller root surface area in poplar. Plant Soil 450, 585–599 (2020).Article 

    Google Scholar 
    Cotrufo, M. F., Ranalli, M. G., Haddix, M. L., Six, J. & Lugato, E. Soil carbon storage informed by particulate and mineral-associated organic matter. Nat. Geosci. 12, 989–994 (2019).Article 

    Google Scholar 
    Brookes, P. C., Landman, A., Pruden, G. & Jenkinson, D. S. Chloroform fumigation and the release of soil nitrogen: a rapid direct extraction method to measure microbial biomass nitrogen in soil. Soil Biol. Biochem. 17, 837–842 (1985).Article 

    Google Scholar 
    Haney, R. L., Franzluebbers, A. J., Hons, F. M. & Zuberer, D. A. Soil C extracted with water or K2SO4: pH effect on determination of microbial biomass. Can. J. Soil Sci. 79, 529–533 (1999).Article 

    Google Scholar 
    Ahmed, M. J. & Hossan, J. Spectrophotometric determination of aluminium by morin. Talanta 42, 1135–1142 (1995).Article 

    Google Scholar 
    Viollier, E., Inglett, P. W., Hunter, K., Roychoudhury, A. N. & Van Cappellen, P. The ferrozine method revisited: Fe(II)/Fe(III) determination in natural waters. Appl. Geochem. 15, 785–790 (2000).Article 

    Google Scholar  More

  • in

    Mapping the planet’s critical natural assets

    Extent and location of critical natural assetsCritical natural assets providing the 12 local NCP (Fig. 1a) occupy only 30% (41 million km2) of total land area (excluding Antarctica) and 24% (34 million km2) of marine Exclusive Economic Zones (EEZs), reflecting the steep slope of the aggregate NCP accumulation curve (Fig. 1b). Despite this modest proportion of global land area, the shares of countries’ land areas that are designated as critical can vary substantially. The 20 largest countries require only 24% of their land area, on average, to maintain 90% of current levels of NCP, while smaller countries (10,000 to 1.5 million km2) require on average 40% of their land area (Supplementary Data 1). This high variability in the NCP–area relationship is primarily driven by the proportion of countries’ land areas made up by natural assets (that is, excluding barren, ice and snow, and developed lands), but even when this is accounted for, there are outliers (Extended Data Fig. 2). Outliers may be due to spatial patterns in human population density (for example, countries with dense population centres and vast expanses with few people, such as Canada and Russia, require far less area to achieve NCP targets) or large ecosystem heterogeneity (if greater ecosystem diversity yields higher levels of diverse NCP in a smaller proportion of area, which may explain patterns in Chile and Australia).The highest-value critical natural assets (the locations delivering the highest magnitudes of NCP in the smallest area, denoted by the darkest blue or green shades in Fig. 1c) often coincide with diverse, relatively intact natural areas near or upstream from large numbers of people. Many of these high-value areas coincide with areas of greatest spatial congruence among multiple NCP (Extended Data Fig. 3). Spatially correlated pairs of local NCP (Supplementary Table 4) include those related to water (flood risk reduction with nitrogen retention and nitrogen with sediment retention); forest products (timber and fuelwood); and those occurring closer to human-modified habitats (pollination with nature access and with nitrogen retention). Coastal risk reduction, forage production for grazing, and riverine fish harvest are the most spatially distinct from other local NCP. In the marine realm, there is substantial overlap of fisheries with coastal risk reduction and reef tourism (though not between the latter two, which each have much smaller critical areas than exist for fisheries).Number of people benefitting from critical natural assetsWe estimate that ~87% of the world’s current population, 6.4 billion people, benefit directly from at least one of the 12 local NCP provided by critical natural assets, while only 16% live on the lands providing these benefits (and they may also benefit; Fig. 2a). To quantify the number of beneficiaries of critical natural assets, we spatially delineate their benefitting areas (which varies on the basis of NCP: for example, areas downstream, within the floodplain, in low-lying areas near the coast, or accessible by a short travel). While our optimization selects for the provision of 90% of the current value of each NCP, it is not guaranteed that 90% of the world’s population would benefit (since it does not include considerations for redundancy in adjacent pixels and therefore many of the areas selected benefit the same populations), so it is notable that an estimated 87% do. This estimate of ‘local’ beneficiaries probably underestimates the total number of people benefitting because it includes only NCP for which beneficiaries can be spatially delineated to avoid double-counting, yet it is striking that the vast majority, 6.1 billion people, live within 1 h travel (by road, rail, boat or foot, taking the fastest path17) of critical natural assets, and more than half of the world’s population lives downstream of these areas (Fig. 2b). Material NCP are often delivered locally, but many also enter global supply chains, making it difficult to delineate beneficiaries spatially for these NCP. However, past studies have calculated that globally more than 54 million people benefit directly from the timber industry18, 157 million from riverine fisheries19, 565 million from marine fisheries20 and 1.3 billion from livestock grazing21, and across the tropics alone 2.7 billion are estimated to be dependent on nature for one or more basic needs22.Fig. 2: People benefitting from and living on critical natural assets (CNA).a,b, ‘Local’ beneficiaries were calculated through the intersection of areas benefitting from different NCP, to avoid double-counting people in areas of overlap; only those NCP for which beneficiaries could be spatially delineated were included (that is, not material NCP that enter global supply chains: fisheries, timber, livestock or crop pollination). Bars show percentages of total population globally and for large and small countries (a) or the percentage of relevant population globally (b). Numbers inset in bars show millions of people making up that percentage. Numbers to the right of bars in b show total relevant population (in millions of people, equivalent to total global population from Landscan 2017 for population within 1 h travel or downstream, but limited to the total population living within 10 km of floodplains or along coastlines 80%) of their populations benefitting from critical natural assets, but small countries have much larger proportions of their populations living within the footprint of critical natural assets than do large countries (Fig. 2a and Supplementary Data 2). When people live in these areas, and especially when current levels of use of natural assets are not sustainable, regulations or incentives may be needed to maintain the benefits these assets provide. While protected areas are an important conservation strategy, they represent only 15% of the critical natural assets for local NCP (Supplementary Table 5); additional areas should not necessarily be protected using designations that restrict human access and use, or they could cease to provide some of the diverse values that make them so critical23. Other area-based conservation measures, such as those based on Indigenous and local communities’ governance systems, Payments for Ecosystem Services programmes, and sustainable use of land- and seascapes, can all contribute to maintaining critical flows of NCP in natural and semi-natural ecosystems24.Overlaps between local and global prioritiesUnlike the 12 local NCP prioritized here at the national scale, certain benefits of natural assets accrue continentally or even globally. We therefore optimize two additional NCP at a global scale: vulnerable terrestrial ecosystem carbon storage (that is, the amount of total ecosystem carbon lost in a typical disturbance event25, hereafter ‘ecosystem carbon’) and vegetation-regulated atmospheric moisture recycling (the supply of atmospheric moisture and precipitation sustained by plant life26, hereafter ‘moisture recycling’). Over 80% of the natural asset locations identified as critical for the 12 local NCP are also critical for the two global NCP (Fig. 3). The spatial overlap between critical natural assets for local and global NCP accounts for 24% of land area, with an additional 14% of land area critical for global NCP that is not considered critical for local NCP (Extended Data Fig. 4). Together, critical natural assets for securing both local and global NCP require 44% of total global land area. When each NCP is optimized individually (carbon and moisture NCP at the global scale; the other 12 at the country scale), the overlap between carbon or moisture NCP and the other NCP exceeds 50% for all terrestrial (and freshwater) NCP except coastal risk reduction (which overlaps only 36% with ecosystem carbon, 5% with moisture recycling; Supplementary Table 4).Fig. 3: Spatial overlaps between critical natural assets for local and global NCP.Red and teal denote where critical natural assets for global NCP (providing 90% of ecosystem carbon and moisture recycling globally) or for local NCP (providing 90% of the 12 NCP listed in Fig. 1), respectively, but not both, occur; gold shows areas where the two overlap (24% of the total area). Together, local and global critical natural assets account for 44% of total global land area (excluding Antarctica). Grey areas show natural assets not defined as ‘critical’ by this analysis, though still providing some values to certain populations. White areas were excluded from the optimization.Full size imageSynergies can also be found between NCP and biodiversity and cultural diversity. Critical natural assets for local NCP at national levels overlap with part or all of the area of habitat (AOH, mapped on the basis of species range maps, habitat preferences and elevation27) for 60% of 28,177 terrestrial vertebrates (Supplementary Data 3). Birds (73%) and mammals (66%) are better represented than reptiles and amphibians (44%). However, these critical natural assets represent only 34% of the area for endemic vertebrate species (with 100% of their AOH located within a given country; Supplementary Data 3) and 16% of the area for all vertebrates if using a more conservative representation target framework based on the IUCN Red List criteria (though, notably, achieving Red List representation targets is impossible for 24% of species without restoration or other expansion of existing AOH; Supplementary Data 4). Cultural diversity (proxied by linguistic diversity) has far higher overlaps with critical natural assets than does biodiversity; these areas intersect 96% of global Indigenous and non-migrant languages28 (Supplementary Data 5). The degree to which languages are represented in association with critical natural assets is consistent across most countries, even at the high end of language diversity (countries containing >100 Indigenous and non-migrant languages, such as Indonesia, Nigeria and India). This high correspondence provides further support for the importance of safeguarding rights to access critical natural assets, especially for Indigenous cultures that benefit from and help maintain them. Despite the larger land area required for maintaining the global NCP compared with local NCP, global NCP priority areas overlap with slightly fewer languages (92%) and with only 2% more species (60% of species AOH), although a substantially greater overlap is seen with global NCP if Red List criteria are considered (36% compared with 16% for local NCP; Supplementary Data 4). These results provide different insights than previous efforts at smaller scales, particularly a similar exercise in Europe that found less overlap with priority areas for biodiversity and NCP29. However, the 40% of all vertebrate species whose habitats did not overlap with critical natural assets could drive very different patterns if biodiversity were included in the optimization.Although these 14 NCP are not comprehensive of the myriad ways that nature benefits and is valued by people23, they capture, spatially and thematically, many elements explicitly mentioned in the First Draft of the CBD’s post-2020 Global Biodiversity Framework13: food security, water security, protection from hazards and extreme events, livelihoods and access to green and blue spaces. Our emphasis here is to highlight the contributions of natural and semi-natural ecosystems to human wellbeing, specifically contributions that are often overlooked in mainstream conservation and development policies around the world. For example, considerations for global food security often include only crop production rather than nature’s contributions to it via pollination or vegetation-mediated precipitation, or livestock production without partitioning out the contribution of grasslands from more intensified feed production.Gaps and next stepsOur synthesis of these 14 NCP represents a substantial advance beyond other global prioritizations that include NCP limited to ecosystem carbon stocks, fresh water and marine fisheries30,31,32, though still falls short of including all important contributions of nature such as its relational values33. Despite the omission of many NCP that were not able to be mapped, further analyses indicate that results are fairly robust to inclusion of additional NCP. Dropping one of the 12 local NCP at a time results in More

  • in

    In-hive learning of specific mimic odours as a tool to enhance honey bee foraging and pollination activities in pear and apple crops

    Study sites and coloniesAll the experiments were carried out during the apple and pear blooming seasons of 2007, 2008, 2011, 2013 and 2014 in different locations of the province of Rio Negro, Argentina, while some laboratory experiments performed in the city of Buenos Aires. We used individual foragers of Apis mellifera L. and their colonies containing a mated queen, brood, and food reserves in ten-frame Langstroth hives. All beehives used had similar sizes and the same management history from the beekeeper. The honey bees studied belonged to commercial Langstroth-type hives rented to pollinate these plots. Each hive had a fertilized queen, 3 or 4 capped brood frames, reserves and approximately 15,000 individuals56.Testing generalization of memories from pear mimic odours to pear and apple natural floral scentsThe absolute conditioning assays were performed in the laboratories of the School of Exacts and Natural Sciences of the University of Buenos Aires (34° 32′ S, 58° 26′ W), Buenos Aires, Argentina. We used honey bee foragers collected at the entrance of the hives settle in the experimental field of the School of Exacts and Natural Sciences. The apple (‘Granny Smith’ and ‘Red Delicious’ varieties) and pear (‘Packham’ and ‘D’anjou’ varieties) bud samples that we used as conditioned stimuli (CS) during the conditioning were collected at the end of the blossom of 2011 in Ingeniero Huergo (39° 03′ 27.5″ S; 67° 13′ 53.5″ W), province of Río Negro, Argentina, and taken to the laboratory in the city of Buenos Aires, Argentina, to be used within the following 2 days.We first developed the three different synthetic mixtures (PM, PMI and PMII) that could be generalized to the fragrance of the pear flower by foraging bees. The pear synthetic mixtures were formulated considering the previously reported volatile profile of pear blossoms57. Then, we chose the synthetic mixture most perceptually similar to the pear flower fragrance and measured its generalisation response to the apple flower fragrance to test the compounds’ specificity. The chemical compounds used to prepare the different synthetic mixtures for the behavioural assays were obtained from Sigma-Aldrich, Steinheim, Germany. The compounds used for the three pear mixtures (PM, PMI and PMII) were composed by alpha-pinene, 2-ethyl-hexanol, (R)-(+)-limonene, and (±)-linalool. For details of the PM and mixture proportions see Patent PCT/IB2018/05555058.To test generalization, we took advantages of the fact that honey bees reflexively extend their proboscises when sugar solution is applied to their antennae59. The proboscis extension reflex (PER) can be used to condition bees to an odour if a neutral olfactory stimulus (CS) is paired with a sucrose reward as unconditioned stimulus, US60. Conditioned honey bees extend their proboscises towards the odour alone, a response that indicates that this stimulus has been learned and predicts the oncoming food reward. Conditioned bees can generalize such a learned response to a novel odour if it is perceived like the conditioned one (CS). Then we performed three absolute PER conditionings where we paired each of the three PMs with a sucrose-water solution (30%) reward along three learning trials (exp. 4.2a). Afterwards, pear floral scent was presented as novel odour to test generalization. Based on the generalization level to the pear odour, we chose the synthetic mixture that showed the highest generalisation towards pear flower fragrance, and we used it in all the experiments that follow. In an additional 3-trial PER conditioning with the chosen mixture, we quantified generalisation towards both the pear and apple fragrances as novel stimuli (exp. 4.2b).The experimental bees were all foragers, captured from colonies that had no access to any pear and/or apple tree, hence completely naïve for the CSs. Immediately after capture, bees were anaesthetized at 4 °C and harnessed in metal tubes so that they could only move their mouthparts and antennae60. They were fed 30% weight/weight unscented sucrose solution for about three seconds and kept in a dark incubator (30 °C, 55% relative humidity) for about two hours. Only those bees that showed the unconditioned response (the reflexive extension of the proboscis after applying a 30% w/w sucrose solution to the antennae) and did not respond to the mechanical air flow stimulus were used. Trials lasted 46 s and presented three steps: 20 s of clean air, 6 s of odour presentation (CS) and the last 20 s of clean air. During rewarded trials (CS), the reward (US, a drop of 30% w/w sucrose solution) was delivered upon the last 3 s of CS presentation. The synthetic mixtures (PM) were delivered in a constant air flow (15 ml/s) that passed through a 1 ml syringe containing 4 µl of the synthetic mixture on a small strip of filter paper. On the other hand, pear and apple floral volatiles were swept from a 100 g of fresh pear buds (var. ‘D’Anjou’ and ‘Packham’) or apple buds (var. ‘Granny Smith’, ‘Gala’ and ‘Red Delicious’) inside a kitasato by means of an air flow (54 ml/s).Testing discrimination between mimics and natural floral scentsThe differential conditioning assays were performed in a field laboratory in Ingeniero Huergo, province of Río Negro, Argentina. Conditioning trials with AM as CS were carried out in September 2007 and 2008, prior to the beginning of flowering of the fruit trees. Conditioning trials with PM as CS were carried out in September 2011 in the same area (Ingeniero Huergo, province of Río Negro, Argentina). Apple and pear bud samples used as CS were collected in plots that start blooming located around Ingeniero Huergo, but distant (more than 1 km) from the plot where we collected the bees. The bud samples presented the following varieties: M. domesticus sp., ‘Granny Smith’, ‘Gala’, and ‘Red Delicious’; P. communis sp., ‘Packham’ and ‘D’Anjou’.With the aim to develop a synthetic mixture that presents difficult to discriminate with the fragrance of the apple flower by foraging bees, an apple synthetic mixture (AM) was formulated considering the previously reported volatile profile of apple blossoms61. The chemical compounds used to prepare the apple synthetic mixtures for the behavioural assays were obtained from Sigma-Aldrich, Steinheim, Germany. Apple mimic (AM) was composed by benzaldehyde, limonene and citral. For details of the AM proportions see Patent AR2011010244162. Jasmine mimic (JM) was a commercial extract obtained from Firmenich S.A.I.C. y F, Argentina.If the synthetic mixture chosen were perceptually similar to the apple flower fragrance, experimental bees should have difficult to discriminate to the apple flower fragrance to test the compounds’ specificity. Thus, we performed differential PER conditioning between synthetic mixtures (AM and Jasmine mimic, JM) or between synthetic mixtures (AM or JM) and the apple natural fragrance. We followed a differential PER conditioning34 to assess to what extent the bees were able to discriminate the synthetic mimics from their natural flower scents. PER differential conditioning consisted of four pairs of trials, four rewarded trials (CS+) and four non-rewarded trials (CS−) that were presented in a pseudo-randomized manner. Conditionings were performed using the synthetic mixtures PM and AM and the natural floral scents, pear and apple, either as CS+ and CS−. We followed the same procedure that in 3.3 to capture the bees and to present the stimuli during trials.Feeding protocolWe used the offering of scented sucrose solution in the hive as a standardized procedure to establish long-term olfactory memory in honey bees23,24,24,26,63. Scented sucrose solution was obtained by diluting 50 µl of PM or AM per litre of sucrose solution (50% weight/weight, henceforth: w/w). For the ‘apple’ series, colonies were fed 1500 ml of sugar solution offered in an internal plastic feeder for 2 days, about 3 days before the apple trees began to bloom. For the ‘pear’ series, hives were fed 500 ml of sugar solution that we spread over the top of the central frames. Both feeding procedures have been found to be functional for establishing olfactory in-hive memories26. Depending on the pear varieties, the scented sucrose solution was offered when the pear trees were 10–40% in bloom.Colony activityThe effects of the AM-treatment on colony nest entrance activity were studied in 18 colonies located in an agricultural setting of apple and pear trees in Ingeniero Huergo, on an 8-ha plot, half of which was planted with apple trees (varieties: ‘Granny Smith’, ‘Gala’ and ‘Red Delicious’) and the other 4 ha with pear trees (varieties: ‘Packham’ and ‘D’anjou’). The effect of the PM-treatment on colony activity was studied in 14 colonies located in three adjoining pear plots (total surface: 8 ha) in Otto Krause (39° 06′ 22″ S 66° 59′ 46″ O, Supplementary Fig. S5), province of Río Negro, Argentina. The varieties of these plots corresponded to ‘Packham’ and ‘Williams’. Pollen collection (exp. 4.5.2) was also studied in colonies located in these plots.We focused on the nest entrance activity since once the first successful foragers return to the hive and display dances and/or unload the food collected, it promotes the activation or reactivation of inactive foragers and, in a minor proportion, those hive mates ready to initiate foraging tasks39,65,66,67,67. Then, we choose number of incoming bees as an indicator of colony foraging activity, since most of these bees are expected to return from foraging sites33. Thus, we compared the activity level at the nest entrance between 7 SS + PM-treated colonies and 7 SS-treated colonies. We also compared the nest entrance activity level between 5 colonies treated with SS + AM and 5 colonies fed with SS. This activity value was estimated by the number of incoming foragers at the entrance of the hive for one minute, every morning at the same time (10:30 a.m.) during the entire experiment (9 consecutive days). A first measurement was done one day before feeding the colonies (used as covariate) and 7 measurements afterwards.We measured the amount of pollen loads collected by two colonies: one fed with SS + PM and one fed with SS. Pollen loads were collected using conventional pollen traps (frontal-entrance trap), consisting of a wooden structure with a removable metal mesh inside. Pollen samples were collected for 3 days, two hours per day during the late morning, 3, 7 and 8 days after the offering of SS + PM or SS. Pollen pellets identified based on pollen colour as coming from the pear flower or from other species were separated and counted. In addition, we estimated the weight of pear pollen loads during a 5 days period, from 6 to 10 days after the offering of scented or unscented sucrose solution. To reduce measurement error, pollen loads were weighed in groups of 10.Crop yieldPear crop yield was studied in pear plots in General Roca (39° 02′ 00″ S; 67° 35′ 00″ O, Supplementary Fig. S4, Supplementary Table S3), province of Río Negro, Argentina. In an area of 15.2 ha (4 plots of 3.8 ha each), 45 beehives were equidistantly located in groups. We measured the number of fruits per tree set of 30 trees in the surrounding areas of the PM-treated colonies (2 groups of 8 hives) and control colonies (2 groups of 8 hives). A third group category contained 13 untreated colonies. The varieties of the pear trees were ‘D’Anjou’ and ‘Packham’.Apple crop yield estimated by means of number of fruits per plant was studied in General Roca (Supplementary Fig. S2, Supplementary Table S1), province of Río Negro, Argentina. We measured fruit set in the two plots that covered a surface of 3.8 ha and contained a total of 74 colonies distributed in groups (the control plot, 39 SS-treated-colonies treated with SS; and the treated plot, 35 SS + AM-treated-colonies treated with SS + AM). The varieties of the apple trees were ‘Red Delicious’ (clone 1), ‘Royal Gala’ and ‘Granny Smith’.A second studied on apple fruit yield by means of kg of fruits per hectare was performed in Coronel Belisle (39° 11′ 00″ S 65° 59′ 00″ O, Supplementary Fig. S3, Supplementary Table S2), province of Río Negro, Argentina. Four apple plots with ‘Granny Smith’, ‘Hi Early’ and ‘Red Delicious’, clone 1 varieties of 15.4 ha each were randomly assigned to different treatments (treated plot 1, 40 SS + AM-treated-hives treated with SS + AM; treated plot 2, 40 SS + AM-treated-hives treated with SS + AM; control plot 1, 40 SS-treated-hives treated with SS; control plot 2, 40 SS-treated-hives treated with SS).During the fruit harvest, the fruit yield was estimated in the surroundings (150 m around) of two groups of 8 colonies each. We fed one group SS + PM and the other unscented sucrose solution (SS). Yield was estimated as the number of fruits per trees in 30 randomly selected trees within each area, alternating the counts between the North and South faces of the plots. Following the same procedure, we also estimated the number of fruits per trees in the surroundings of two groups of 14 colonies each that pollinated apple crops. Again, we fed one group SS + AM and the other SS. Additionally, a total of 218 colonies in General Roca and 180 colonies in Coronel Belisle have been separated in the two experimental groups, in which yield had been provided by the producer and expressed in kg of fruits per ha. It is worth remarking that in some plots the distance between treated and control beehive groups was around 300 m, suggesting that might have been overlapping flying areas between treated and control hives. Additionally, the apple fields studied in the surrounding of Coronel Belisle, presented many trees without flowers. It was considered that the absence of flowers in numerous trees would bias the counts performed in those fields. Then, to quantify this situation, which might be associated with the masting phenomenon68, samples with the proportions of trees without flowers for every 20 trees in each plot was done. Trees that had between 80 and 100% of their surface devoid of flowers were considered “without flowers” trees, and “trees with available flowers” those that had more than 20% of their surface covered with flowers. An average of 30% of the trees within these plots were devoid of flowers. Thus, a correction factor was considered to evaluate the yield data provided by the grower per plot analysed (Supplementary Table S4).StatisticsAll statistical analyses were performed with R Core Team 201969. For Experiment 4.2 and 4.3, we analysed PER proportion by means of a binomial multiplicative generalized linear mixed model using the “glmer” function of the ‘lme4’ package70.For experiment 4.2a we considered the pear mimics (three-level factor corresponding to PM, PMI and PMII) and the event (two-level factor corresponding to 3rd trial and test) as fixed factors and each “bee” as a random factor.For experiment 4.2b we considered the tested odours (three-level factor corresponding to Apple, Pear and PM) as fixed factors.For experiment 4.3 we considered the tested odours (two-level factor corresponding to CS+ and CS−) as fixed factors. Post hoc contrasts were conducted on models to assess effects and significance between fixed factors using the “emmeans” function of the ‘emmeans’ package version 1.7.071 with a significance level of 0.05.For experiment 4.5.1 we analysed “rate of incoming bees” using a generalized linear mixed model. As Poisson model for incoming bees was overdispersed72, we used a negative binomial distribution using the ‘glmmTMB’ package (function ‘glmmTMB’73. We considered “treatment” [two-level factor corresponding to SS + AM (or SS + PM) and SS], “days” (7-level factor corresponding to the date after treatment), the rate of incoming bees before the offering of food (to control for pre-existing colony differences) as covariate (a quantitative fixed effects variable), and “colony” as a random factor.For experiment 4.6, we analysed fruits per trees by means of a negative binomial multiplicative generalized linear mixed model using the “log” function of the ‘ml’ package70. Post hoc contrasts were conducted on models to assess effects and significance between fixed factors using the “emmeans” function of the ‘emmeans’ package version 1.8.071 with a significance level of 0.05. For experiment 4.6b we analysed “yield” (as weight of fruits per unit area) using a general linear mixed model. We checked homoscedasticity and normality assumptions (Levene and Shapiro–Wilk tests, respectively). We considered “treatment” (two-level factor corresponding to SS + AM and SS) and “apple varieties” (3-level factor corresponding to Hi Early, Granny Smith and Chañar 28) as fixed factors and “location” (2-level factor corresponding to General Roca and Coronel Belisle) as random factors. More

  • in

    Implications of zero-deforestation palm oil for tropical grassy and dry forest biodiversity

    Curtis, P. G., Slay, C. M., Harris, N. L., Tyukavina, A. & Hansen, M. C. Classifying drivers of global forest loss. Science 361, 1108–1111 (2018).CAS 
    PubMed 

    Google Scholar 
    Laurance, W. F., Sayer, J. & Cassman, K. G. Agricultural expansion and its impacts on tropical nature. Trends Ecol. Evol. 29, 107–116 (2014).PubMed 

    Google Scholar 
    Pendrill, F. et al. Agricultural and forestry trade drives large share of tropical deforestation emissions. Glob. Environ. Change 56, 1–10 (2019).
    Google Scholar 
    Haupt, F., Bakhtary, H., Schulte, I., Galt, H. & Streck, C. Progress on Corporate Commitments and their Implementation (Tropical Forest Alliance, 2018); https://www.tropicalforestalliance.org/assets/Uploads/Progress-on-Corporate-Commitments-and-their-Implementation.pdfAustin, K. G. et al. Mapping and monitoring zero-deforestation commitments. Bioscience 71, 1079–1090 (2021).PubMed 
    PubMed Central 

    Google Scholar 
    Leijten, F. C., Sim, S., King, H. & Verburg, P. H. Which forests could be protected by corporate zero deforestation commitments? A spatial assessment. Environ. Res. Lett. 15, 064021 (2020).
    Google Scholar 
    Garrett, R. D. et al. Criteria for effective zero-deforestation commitments. Glob. Environ. Change https://doi.org/10.1016/j.gloenvcha.2018.11.003 (2019).Lehmann, C. E. R. & Parr, C. L. Tropical grassy biomes: linking ecology, human use and conservation. Phil. Trans. R. Soc. B https://doi.org/10.1098/rstb.2016.0329 (2016).Miles, L. et al. A global overview of the conservation status of tropical dry forests. J. Biogeogr. 33, 491–505 (2006).
    Google Scholar 
    Gibbs, H. K. et al. Brazil’s soy moratorium. Science https://doi.org/10.1126/science.aaa0181 (2015).Jopke, P. & Schoneveld, G. C. Corporate Commitments to Zero Deforestation: An Evaluation of Externality Problems and Implementation Gaps (CIFOR, 2018); https://doi.org/10.17528/cifor/006827Parr, C. L., Lehmann, C. E. R., Bond, W. J., Hoffmann, W. A. & Andersen, A. N. Tropical grassy biomes: misunderstood, neglected, and under threat. Trends Ecol. Evol. https://doi.org/10.1016/j.tree.2014.02.004 (2014).Ratnam, J. et al. When is a ‘forest’ a savanna, and why does it matter? Glob. Ecol. Biogeogr. https://doi.org/10.1111/j.1466-8238.2010.00634.x (2011).Sanchez-Azofeifa, G. A. et al. Research priorities for neotropical dry forests. Biotropica 37, 477–485 (2005).
    Google Scholar 
    Vijay, V., Pimm, S. L., Jenkins, C. N. & Smith, S. J. The impacts of oil palm on recent deforestation and biodiversity loss. PLoS ONE 11, e0159668 (2016).PubMed 
    PubMed Central 

    Google Scholar 
    Principles & Criteria for the Production of Sustainable Palm Oil (RSPO, 2018).Rosoman, G. et al. (eds) The HCS Approach Toolkit (HCS Approach Steering Group, 2017).Brown, E. & Senior, M. J. M. (eds) Common Guidance for the Identification of High Conservation Values (HCV Resource Network, 2017).Furumo, P. R. & Aide, T. M. Characterizing commercial oil palm expansion in Latin America: land use change and trade. Environ. Res. Lett. 12, 024008 (2017).
    Google Scholar 
    Dinerstein, E. et al. An ecoregion-based approach to protecting half the terrestrial realm. BioScience https://doi.org/10.1093/biosci/bix014 (2017).Descals, A. et al. High-resolution global map of smallholder and industrial closed-canopy oil palm plantations. Earth Syst. Sci. Data 13, 1211–1231 (2021).
    Google Scholar 
    Woittiez, L. S., van Wijk, M. T., Slingerland, M., van Noordwijk, M. & Giller, K. E. Yield gaps in oil palm: a quantitative review of contributing factors. Eur. J. Agron. 83, 57–77 (2017).
    Google Scholar 
    Kuepper, B., Drost, S. & Piotrowski, M. Latin American Palm Oil Linked to Social Risks, Local Deforestation (Chain Reaction Research, 2021); https://chainreactionresearch.com/wp-content/uploads/2021/12/Latin-American-Palm-Oil-Linked-to-Social-Issues-Local-Deforestation-1.pdfHoyle, D. et al. RSPO New Planting Procedures: Summary Report of ESIA, HCV Assessments and Management Plan (Terea, Proforest and Olam Palm Gabon, 2017).Universal Mill List (World Resources Institute, Rainforest Alliance, Proforest & Daemeter, 2018); https://data.globalforestwatch.org/documents/gfw::universal-mill-list/aboutPirker, J., Mosnier, A., Kraxner, F., Havlík, P. & Obersteiner, M. What are the limits to oil palm expansion? Glob. Environ. Change 40, 73–81 (2016).
    Google Scholar 
    Fischer, G. et al. Global Agro-Ecological Zones 4 (GAEZ v4) – Model Documentation (FAO, 2021); https://doi.org/10.4060/cb4744enGlobal Agro-Ecological Zoning Version 4 (GAEZ v4) (FAO & IIASA, 2021); http://www.fao.org/gaez/Tao, H. H. et al. Long-term crop residue application maintains oil palm yield and temporal stability of production. Agron. Sustain. Dev. https://doi.org/10.1007/s13593-017-0439-5 (2017).Wei, L., John Martin, J. J., Zhang, H., Zhang, R. & Cao, H. Problems and prospects of improving abiotic stress tolerance and pathogen resistance of oil palm. Plants 10, 2622 (2021).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    Corley, R. H. & Tinker, P. B. The Oil Palm (Wiley-Blackwell, 2016).Barona, E., Ramankutty, N., Hyman, G. & Coomes, O. T. The role of pasture and soybean in deforestation of the Brazilian Amazon. Environ. Res. Lett. 5, 024002 (2010).
    Google Scholar 
    ten Kate, A., Kuepper, B. & Piotrowski, M. NDPE Policies Cover 83% of Palm Oil Refineries; Implementation at 78% (Chain Reaction Research, 2020); https://chainreactionresearch.com/wp-content/uploads/2020/04/NDPE-Policies-Cover-83-of-Palm-Oil-Refining-Market.pdfThe Trase Yearbook: The State Of Forest Risk Supply Chains (Trase, 2020); https://insights.trase.earth/yearbook/summaryAustin, K. G. et al. Shifting patterns of oil palm driven deforestation in Indonesia and implications for zero-deforestation commitments. Land Use Policy 69, 41–48 (2017).
    Google Scholar 
    Furumo, P. R., Rueda, X., Rodríguez, J. S. & Parés Ramos, I. K. Field evidence for positive certification outcomes on oil palm smallholder management practices in Colombia. J. Clean. Prod. 245, 118891 (2020).
    Google Scholar 
    Carlson, K. M. et al. Effect of oil palm sustainability certification on deforestation and fire in Indonesia. Proc. Natl Acad. Sci. USA 115, 121–126 (2018).CAS 
    PubMed 

    Google Scholar 
    Heilmayr, R., Carlson, K. M. & Benedict, J. J. Deforestation spillovers from oil palm sustainability certification. Environ. Res. Lett. 15, 075002 (2020).CAS 

    Google Scholar 
    Impact (RSPO, 2022); https://www.rspo.org/impactBastos Lima, M. G., Persson, U. M. & Meyfroidt, P. Leakage and boosting effects in environmental governance: a framework for analysis. Environ. Res. Lett. 14, 105006 (2019).
    Google Scholar 
    Corley, R. H. V. How much palm oil do we need? Environ. Sci. Policy https://doi.org/10.1016/j.envsci.2008.10.011 (2009).FAOSTAT: Food and Agriculture Data (FAO, 2020); https://www.fao.org/faostat/en/Olson, D. M. et al. Terrestrial ecoregions of the world: a new map of life on Earth: a new global map of terrestrial ecoregions provides an innovative tool for conserving biodiversity. BioScience 51, 933–938 (2001).
    Google Scholar 
    Murphy, B. P., Andersen, A. N. & Parr, C. L. The underestimated biodiversity of tropical grassy biomes. Phil. Trans. R. Soc. B 371, 20150319 (2016).PubMed 
    PubMed Central 

    Google Scholar 
    Smith, J. R., Hendershot, J. N., Nova, N. & Daily, G. C. The biogeography of ecoregions: descriptive power across regions and taxa. J. Biogeogr. https://doi.org/10.1111/jbi.13871 (2020).Klink, C. A. & Machado, R. B. Conservation of the Brazilian Cerrado. Conserv. Biol. 19, 707–713 (2005).
    Google Scholar 
    Strassburg, B. B. N. et al. Moment of truth for the Cerrado hotspot. Nat. Ecol. Evol. https://doi.org/10.1038/s41559-017-0099 (2017).le Polain de Waroux, Y. et al. The restructuring of South American soy and beef production and trade under changing environmental regulations. World Dev. 121, 188–202 (2019).
    Google Scholar 
    Nepstad, L. S. et al. Pathways for recent Cerrado soybean expansion: extending the soy moratorium and implementing integrated crop livestock systems with soybeans. Environ. Res. Lett. 14, 044029 (2019).
    Google Scholar 
    Searchinger, T. D. et al. High carbon and biodiversity costs from converting Africa’s wet savannahs to cropland. Nat. Clim. Change https://doi.org/10.1038/nclimate2584 (2015).Cardoso Da Silva, J. M. & Bates, J. M. Biogeographic patterns and conservation in the South American Cerrado: a tropical savanna hotspot. BioScience 52, 225–233 (2002).
    Google Scholar 
    Poggio, L. et al. SoilGrids 2.0: producing soil information for the globe with quantified spatial uncertainty. SOIL 7, 217–240 (2021).Hill, T. C., Williams, M., Bloom, A. A., Mitchard, E. T. A. & Ryan, C. M. Are inventory based and remotely sensed above-ground biomass estimates consistent? PLoS ONE https://doi.org/10.1371/journal.pone.0074170 (2013).Ryan, C. M. et al. Ecosystem services from southern African woodlands and their future under global change. Phil. Trans. R. Soc. B https://doi.org/10.1098/rstb.2015.0312 (2016).Grace, J., Jose, J. S., Meir, P., Miranda, H. S. & Montes, R. A. Productivity and carbon fluxes of tropical savannas. J. Biogeogr. 33, 387–400 (2006).
    Google Scholar 
    Scharlemann, J. P., Tanner, E. V., Hiederer, R. & Kapos, V. Global soil carbon: understanding and managing the largest terrestrial carbon pool. Carbon Manag. 5, 81–91 (2014).CAS 

    Google Scholar 
    Quezada, J. C., Etter, A., Ghazoul, J., Buttler, A. & Guillaume, T. Carbon neutral expansion of oil palm plantations in the Neotropics. Sci. Adv. 5, eaaw4418 (2019).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    Aleman, J. C., Blarquez, O. & Staver, C. A. Land-use change outweighs projected effects of changing rainfall on tree cover in sub-Saharan Africa. Glob. Change Biol. https://doi.org/10.1111/gcb.13299 (2016).Espírito-Santo, M. M. et al. Understanding patterns of land-cover change in the Brazilian Cerrado from 2000 to 2015. Phil. Trans. R. Soc. B https://doi.org/10.1098/rstb.2015.0435 (2016).Overbeck, G. E. et al. Conservation in Brazil needs to include non-forest ecosystems. Divers. Distrib. https://doi.org/10.1111/ddi.12380 (2015).Hoekstra, J. M., Boucher, T. M., Ricketts, T. H. & Roberts, C. Confronting a biome crisis: global disparities of habitat loss and protection. Ecol. Lett. https://doi.org/10.1111/j.1461-0248.2004.00686.x (2005).RTRS Standard for Responsible Soy Production Version 3.1 (RTRS, 2017); https://responsiblesoy.org/wp-content/uploads/2019/08/RTRS%20Standard%20Responsible%20Soy%20production%20V3.1%20ING-LOW.pdfBatlle-Bayer, L., Batjes, N. H. & Bindraban, P. S. Changes in organic carbon stocks upon land use conversion in the Brazilian Cerrado: a review. Agric. Ecosyst. Environ. 137, 47–58 (2010).CAS 

    Google Scholar 
    Rockström, J., Falkenmark, M., Lannerstad, M. & Karlberg, L. The planetary water drama: dual task of feeding humanity and curbing climate change. Geophys. Res. Lett. 39, LXXXXX (2012).
    Google Scholar 
    Ocampo-Peñuela, N., Garcia-Ulloa, J., Ghazoul, J. & Etter, A. Quantifying impacts of oil palm expansion on Colombia’s threatened biodiversity. Biol. Conserv. https://doi.org/10.1016/j.biocon.2018.05.024 (2018).Gilroy, J. J. et al. Minimizing the biodiversity impact of Neotropical oil palm development. Glob. Change Biol. 21, 1531–1540 (2015).
    Google Scholar 
    Bonn Challenge 2020 Report (IUCN, 2020); https://www.bonnchallenge.org/resources/bonn-challenge-2020-reportGilroy, J. J. et al. Cheap carbon and biodiversity co-benefits from forest regeneration in a hotspot of endemism. Nat. Clim. Change 4, 503–507 (2014).
    Google Scholar 
    Evans, M. C. et al. Carbon farming via assisted natural regeneration as a cost-effective mechanism for restoring biodiversity in agricultural landscapes. Environ. Sci. Policy 50, 114–129 (2015).CAS 

    Google Scholar 
    Hunter, M. C., Smith, R. G., Schipanski, M. E., Atwood, L. W. & Mortensen, D. A. Agriculture in 2050: recalibrating targets for sustainable intensification. BioScience https://doi.org/10.1093/biosci/bix010 (2017).Beyer, R. & Rademacher, T. Species richness and carbon footprints of vegetable oils: can high yields outweigh palm oil’s environmental impact? Sustainability 13, 1813 (2021).
    Google Scholar 
    Lee, J. S. H., Ghazoul, J., Obidzinski, K. & Koh, L. P. Oil palm smallholder yields and incomes constrained by harvesting practices and type of smallholder management in Indonesia. Agron. Sustain. Dev. 34, 501–513 (2014).
    Google Scholar 
    Murphy, D. J. The future of oil palm as a major global crop: opportunities and challenges. J. Oil Palm Res. 26, 1–24 (2014).
    Google Scholar 
    Giam, X., Koh, L. P. & Wilcove, D. S. Tropical crops: cautious optimism. Science https://doi.org/10.1126/science.346.6212.928-a (2014).Villoria, N. B., Golub, A., Byerlee, D. & Stevenson, J. Will yield improvements on the forest frontier reduce greenhouse gas emissions? A global analysis of oil palm. Am. J. Agric. Econ. 95, 1301–1308 (2013).
    Google Scholar 
    Koh, L. P. & Lee, T. M. Sensible consumerism for environmental sustainability. Biol. Conserv. https://doi.org/10.1016/j.biocon.2011.10.029 (2012).Fick, S. E. & Hijmans, R. J. WorldClim 2: new 1-km spatial resolution climate surfaces for global land areas. Int. J. Climatol. 37, 4302–4315 (2017).
    Google Scholar 
    Harris, N., Goldman, E. & Gibbes, S. Spatial Database of Planted Trees (SDPT) Version 1.0 (World Resources Institute, 2019); https://data.globalforestwatch.org/datasets/tree-plantationsSutanudjaja, E. H. et al. PCR-GLOBWB 2: a 5 arcmin global hydrological and water resources model. Geosci. Model Dev. 11, 2429–2453 (2018).
    Google Scholar 
    Global Land Cover (Copernicus, 2019); https://lcviewer.vito.be/Tsendbazar, N.-E. et al. Copernicus Global Land Operations ‘Vegetation and Energy’ ‘CGLOPS−1’ Validation Report. Moderate Dynamic Land Cover 100m Version 2 (WUR, 2019); https://land.copernicus.eu/global/sites/cgls.vito.be/files/products/CGLOPS1_VR_LC100m-V2.0_I1.00.pdfSantoro, M. et al. GlobBiomass – global datasets of forest biomass. PANGAEA https://doi.org/10.1594/PANGAEA.894711 (2018).Santoro, M. et al. A detailed portrait of the forest aboveground biomass pool for the year 2010 obtained from multiple remote sensing observations. Geophys. Res. Abstr. https://doi.org/10.1002/joc.5086 (2018).Hansen, M. C. et al. High-resolution global maps of 21st-century forest cover change. Science https://doi.org/10.1126/science.1244693 (2013).Gumbricht, T. et al. Tropical and Subtropical Wetlands Distribution Version 7 (CIFOR, 2017); https://doi.org/10.17528/CIFOR/DATA.00058The IUCN Red List of Threatened Species Version 2018−1 (IUCN, 2018); https://www.iucnredlist.orgBird Species Distribution Maps of the World Version 6.0 (BirdLife International & Handbook of the Birds of the World, 2016); http://datazone.birdlife.org/species/requestdisR Core Team. R: A Language and Environment for Statistical Computing (R Foundation for Statistical Computing, 2018).Silalertruksa, T. et al. Environmental sustainability of oil palm cultivation in different regions of Thailand: greenhouse gases and water use impact. J. Clean. Prod. 167, 1009–1019 (2017).CAS 

    Google Scholar 
    Fourcade, Y., Engler, J. O., Rödder, D. & Secondi, J. Mapping species distributions with Maxent using a geographically biased sample of presence data: a performance assessment of methods for correcting sampling bias. PLoS ONE 9, e97122 (2014).PubMed 
    PubMed Central 

    Google Scholar 
    Liu, Z. et al. Shifts in the extent and location of rice cropping areas match the climate change pattern in China during 1980–2010. Reg. Environ. Change https://doi.org/10.1007/s10113-014-0677-x (2015).Singh, K., McClean, C. J., Büker, P., Hartley, S. E. & Hill, J. K. Mapping regional risks from climate change for rainfed rice cultivation in India. Agric. Syst. 156, 76–84 (2017).PubMed 
    PubMed Central 

    Google Scholar 
    Estes, L. D. et al. Comparing mechanistic and empirical model projections of crop suitability and productivity: implications for ecological forecasting. Glob. Ecol. Biogeogr. https://doi.org/10.1111/geb.12034 (2013).Thuiller, W., Georges, D., Engler, R. & Breiner, F. biomod2: Ensemble Platform for Species Distribution Modelling (2016).Hernandez, P. A., Graham, C. H., Master, L. L. & Albert, D. L. The effect of sample size and species characteristics on performance of different species distribution modeling methods. Ecography 29, 773–785 (2006).
    Google Scholar 
    Merow, C., Smith, M. J., Silander, J. A., Merow, C. & Silander, J. A. A practical guide to Maxent for modeling species’ distributions: what it does, and why inputs and settings matter. Ecography 36, 1058–1069 (2013).
    Google Scholar 
    Phillips, S. J., Anderson, R. P. & Schapire, R. E. Maximum entropy modeling of species geographic distributions. Ecol. Modell. https://doi.org/10.1016/j.ecolmodel.2005.03.026 (2006).VanDerWal, J., Shoo, L. P., Graham, C. & Williams, S. E. Selecting pseudo-absence data for presence-only distribution modeling: how far should you stray from what you know? Ecol. Modell. 220, 589–594 (2009).
    Google Scholar 
    Hirzel, A. H., Le Lay, G., Helfer, V., Randin, C. F. & Guisan, A. Evaluating the ability of habitat suitability models to predict species presences. Ecol. Modell. 199, 142–152 (2006).
    Google Scholar 
    Engler, R., Guisan, A. & Rechsteiner, L. An improved approach for predicting the distribution of rare and endangered species from occurrence and pseudo-absence data. J. Appl. Ecol. https://doi.org/10.1111/j.0021-8901.2004.00881.x (2004).Allouche, O., Tsoar, A. & Kadmon, R. Assessing the accuracy of species distribution models: prevalence, kappa and the true skill statistic (TSS). J. Appl. Ecol. https://doi.org/10.1111/j.1365-2664.2006.01214.x (2006).Global Spatially-Disaggregated Crop Production Statistics Data for 2010 Version 1.1. (International Food Policy Research Institute, 2019); https://doi.org/10.7910/DVN/PRFF8V/M2EMBNHofste, R. W. et al. Aqueduct 3.0: Updated Decision-Relevant Global Water Risk Indicators (World Resources Institute, 2019); https://www.wri.org/research/aqueduct-30-updated-decision-relevant-global-water-risk-indicatorsCarr, M. K. V. The water relations and irrigation requirements of oil palm (Elaeis guineensis): a review. Exp. Agric. 47, 629–652 (2011).
    Google Scholar 
    Yusop, Z., Hui, C. M., Garusu, G. J. & Katimon, A. Estimation of evapotranspiration in oil palm catchments by short-time period water-budget method. Malays. J. Civ. Eng. 20, 160–174 (2008).
    Google Scholar 
    Hargreaves, G. H. & Allen, R. G. History and evaluation of Hargreaves evapotranspiration equation. J. Irrig. Drain. Eng. 129, 53–63 (2003).
    Google Scholar 
    Trabucco, A. & Zomer, R. J. Global aridity index and potential evapotranspiration (ET0) climate database v2. Figshare https://doi.org/10.6084/m9.figshare.7504448.v3 (2019).Protected Planet: The World Database on Protected Areas (WDPA) (UNEP-WCMC & IUCN, 2020); www.protectedplanet.net/en/thematic-areas/wdpaDudley, N. (ed.) Guidelines for Applying Protected Area Management Categories (IUCN, 2008).Juffe-Bignoli, D. et al. World Database on Protected Areas User Manual 1.5 (UNEP-WCMC, 2017); https://www.protectedplanet.net/en/resources/wdpa-manualChave, J. J. et al. Tree allometry and improved estimation of carbon stocks and balance in tropical forests. Oecologia 145, 87–99 (2005).CAS 
    PubMed 

    Google Scholar 
    Jetz, W., Wilcove, D. S. & Dobson, A. P. Projected impacts of climate and land-use change on the global diversity of birds. PLoS Biol. https://doi.org/10.1371/journal.pbio.0050157 (2007).Beyer, R. M. & Manica, A. Historical and projected future range sizes of the world’s mammals, birds, and amphibians. Nat. Commun. 11, 5633 (2020).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    Beyer, R. M. & Manica, A. Global and country-level data of the biodiversity footprints of 175 crops and pasture. Data Brief 36, 106982 (2021).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    Cobertura de la Tierra 100K Periodo 2018 (IDEAM, Instituto de Hidrología, Meteorología y Estudios Ambientales, 2021); http://www.siac.gov.co/catalogo-de-mapasSouza, C. M. et al. Reconstructing three decades of land use and land cover changes in Brazilian biomes with Landsat archive and Earth Engine. Remote Sens. 12, 2735 (2020).
    Google Scholar 
    MapBiomas Project – Collection 6 of the Annual Series of Land Use and Land Cover Maps of Brazil (MapBiomas, 2021); https://plataforma.brasil.mapbiomas.org/Veldman, J. W. & Putz, F. E. Grass-dominated vegetation, not species-diverse natural savanna, replaces degraded tropical forests on the southern edge of the Amazon Basin. Biol. Conserv. https://doi.org/10.1016/j.biocon.2011.01.011 (2011).Portillo-Quintero, C. A. & Sánchez-Azofeifa, G. A. Extent and conservation of tropical dry forests in the Americas. Biol. Conserv. https://doi.org/10.1016/j.biocon.2009.09.020 (2010).Veldman, J. W. et al. Toward an old-growth concept for grasslands, savannas, and woodlands. Front. Ecol. Environ. https://doi.org/10.1890/140270 (2015).Zaloumis, N. P. & Bond, W. J. Reforestation or conservation? The attributes of old growth grasslands in South Africa. Phil. Trans. R. Soc. B https://doi.org/10.1098/rstb.2015.0310 (2016).Garnett, S. T. et al. A spatial overview of the global importance of Indigenous lands for conservation. Nat. Sustain. https://doi.org/10.1038/s41893-018-0100-6 (2018).Djoudi, H., Vergles, E., Blackie, R. R., Koame, C. K. & Gautier, D. Dry forests, livelihoods and poverty alleviation: understanding current trends. Int. For. Rev. https://doi.org/10.1505/146554815815834868 (2015).Ground-Truthing to Improve Due Diligence on Human Rights in Deforestation-Risk Supply Chains (Forest Peoples Programme, 2020); https://www.forestpeoples.org/en/ground-truthing-to-improve-due-diligenceDrost, S., Rijk, G. & Piotrowski, M. Oil Palm Growers Exposed to USD 0.4-5.9B in Social Compensation Risk (Chain Reaction Research, 2019); https://chainreactionresearch.com/wp-content/uploads/2019/12/Social-compensation-risks-for-palm-growers-4.pdf More

  • in

    Limited carbon cycling due to high-pressure effects on the deep-sea microbiome

    Aristegui, J., Gasol, J. M., Duarte, C. M. & Herndl, G. J. Microbial oceanography of the dark ocean’s pelagic realm. Limnol. Oceanogr. 54, 1501–1529 (2009).Article 

    Google Scholar 
    Jannasch, H. W., Eimhjellen, K., Wirsen, C. O. & Farmanfarmaian, A. Microbial degradation of organic matter in the deep sea. Science 171, 672–675 (1971).Article 

    Google Scholar 
    Tamburini, C., Boutrif, M., Garel, M., Colwell, R. R. & Deming, J. W. Prokaryotic responses to hydrostatic pressure in the ocean – a review. Environ. Microbiol. 15, 1262–1274 (2013).Article 

    Google Scholar 
    Yayanos, A. A. Microbiology to 10,500 meters in the deep-sea. Annu. Rev. Microb. 49, 777–805 (1995).Article 

    Google Scholar 
    Jebbar, M., Franzetti, B., Girard, E. & Oger, P. Microbial diversity and adaptation to high hydrostatic pressure in deep-sea hydrothermal vents prokaryotes. Extremophiles 19, 721–740 (2015).Article 

    Google Scholar 
    Yayanos, A. A. Evolutional and ecological implications of the properties of deep-sea barophilic bacteria. Proc. Natl Acad. Sci. USA 83, 9542–9546 (1986).Article 

    Google Scholar 
    Nagata, T. et al. Emerging concepts on microbial processes in the bathypelagic ocean – ecology, biogeochemistry, and genomics. Deep-Sea Res. II 57, 1519–1536 (2010).Article 

    Google Scholar 
    Picard, A. & Daniel, I. Pressure as an environmental parameter for microbial life – a review. Biophys. Chem. 183, 30–41 (2013).Article 

    Google Scholar 
    Herndl, G. J. & Reinthaler, T. Microbial control of the dark end of the biological pump. Nat. Geosci. 6, 718–724 (2013).Article 

    Google Scholar 
    Marietou, A. & Bartlett, D. H. Effects of high hydrostatic pressure on coastal bacterial community abundance and diversity. Appl. Environ. Microbiol. 80, 5992–6003 (2014).Article 

    Google Scholar 
    Lauro, F. M. & Bartlett, D. H. Prokaryotic lifestyles in deep sea habitats. Extremophiles 12, 15–25 (2008).Article 

    Google Scholar 
    Peoples, L. M. et al. Distinctive gene and protein characteristics of extremely piezophilic Colwellia. BMC Genom. 21, 692 (2020).Article 

    Google Scholar 
    Reinthaler, T. et al. Prokaryotic respiration and production in the meso- and bathypelagic realm of the eastern and western North Atlantic basin. Limnol. Oceanogr. 51, 1262–1273 (2006).Article 

    Google Scholar 
    Steinberg, D. K. et al. Bacterial vs. zooplankton control of sinking particle flux in the ocean’s twilight zone. Limnol. Oceanogr. 53, 1327–1338 (2008).Article 

    Google Scholar 
    Burd, A. B. et al. Assessing the apparent imbalance between geochemical and biochemical indicators of meso- and bathypelagic biological activity: what the @$#! is wrong with present calculations of carbon budgets? Deep-Sea Res. II 57, 1557–1571 (2010).Article 

    Google Scholar 
    Boyd, P. W., Claustre, H., Levy, M., Siegel, D. A. & Weber, T. Multi-faceted particle pumps drive carbon sequestration in the ocean. Nature 568, 327–335 (2019).Article 

    Google Scholar 
    Kirchman, D., Knees, E. & Hodson, R. Leucine incorporation and its potential as a measure of protein-synthesis by bacteria in natural aquatic systems. Appl. Environ. Microbiol. 49, 599–607 (1985).Article 

    Google Scholar 
    Nielsen, J. L., Christensen, D., Kloppenborg, M. & Nielsen, P. H. Quantification of cell-specific substrate uptake by probe-defined bacteria under in situ conditions by microautoradiography and fluorescence in situ hybridization. Environ. Microbiol. 5, 202–211 (2003).Article 

    Google Scholar 
    Sintes, E. & Herndl, G. J. Quantifying substrate uptake by individual cells of marine bacterioplankton by catalyzed reporter deposition fluorescence in situ hybridization combined with micro autoradiography. Appl. Environ. Microbiol. 72, 7022–7028 (2006).Article 

    Google Scholar 
    Garel, M. et al. Pressure-retaining sampler and high-pressure systems to study deep-sea microbes under in situ conditions. Front. Microbiol 10, 453 (2019).Article 

    Google Scholar 
    Peoples, L. M. et al. A full-ocean-depth rated modular lander and pressure-retaining sampler capable of collecting hadal-endemic microbes under in situ conditions. Deep-Sea Res. I 143, 50–57 (2019).Article 

    Google Scholar 
    Gross, M. & Jaenicke, R. Proteins under pressure – the influence of high hydrostatic pressure on structure, function and assembly of proteins and protein complexes. Eur. J. Biochem. 221, 617–630 (1994).Article 

    Google Scholar 
    Kirchman, D. L. Growth rates of microbes in the oceans. Annu. Rev. Mar. Sci. 8, 285–309 (2016).Article 

    Google Scholar 
    Ashburner, M. et al. Gene ontology: tool for the unification of biology. Nat. Genet. 25, 25–29 (2000).Article 

    Google Scholar 
    Xie, Z., Jian, H., Jin, Z. & Xiao, X. Enhancing the adaptability of the deep-sea bacterium Shewanella piezotolerans WP3 to high pressure and low temperature by experimental evolution under H2O2 stress. Appl. Environ. Microbiol. 84, e02342–02317 (2018).Article 

    Google Scholar 
    Tamburini, C. et al. Effects of hydrostatic pressure on microbial alteration of sinking fecal pellets. Deep-Sea Res. II 56, 1533–1546 (2009).Article 

    Google Scholar 
    Ivars-Martinez, E. et al. Comparative genomics of two ecotypes of the marine planktonic copiotroph Alteromonas macleodii suggests alternative lifestyles associated with different kinds of particulate organic matter. ISME J. 2, 1194–1212 (2008).Article 

    Google Scholar 
    Zhao, Z., Baltar, F. & Herndl, G. J. Linking extracellular enzymes to phylogeny indicates a predominantly particle-associated lifestyle of deep-sea prokaryotes. Sci. Adv. 6, eaaz4354 (2020).Article 

    Google Scholar 
    Bochdansky, A. B., van Aken, H. M. & Herndl, G. J. Role of macroscopic particles in deep-sea oxygen consumption. Proc. Natl Acad. Sci. USA 107, 8287–8291 (2010).Article 

    Google Scholar 
    Chikuma, S., Kasahara, R., Kato, C. & Tamegai, H. Bacterial adaptation to high pressure: a respiratory system in the deep-sea bacterium Shewanella violacea DSS12. FEMS Microbiol. Lett. 267, 108–112 (2007).Article 

    Google Scholar 
    Qin, Q. L. et al. Oxidation of trimethylamine to trimethylamine N-oxide facilitates high hydrostatic pressure tolerance in a generalist bacterial lineage. Sci. Adv. 7, eabf9941 (2021).Article 

    Google Scholar 
    Mestre, M. et al. Sinking particles promote vertical connectivity in the ocean microbiome. Proc. Natl Acad. Sci. USA 115, E6799–E6807 (2018).Article 

    Google Scholar 
    Thiele, S., Fuchs, B. M., Amann, R. & Iversen, M. H. Colonization in the photic zone and subsequent changes during sinking determine bacterial community composition in marine snow. Appl. Environ. Microbiol. 81, 1463–1471 (2015).Article 

    Google Scholar 
    Tada, Y. et al. Differing growth responses of major phylogenetic groups of marine bacteria to natural phytoplankton blooms in the western North Pacific Ocean. Appl. Environ. Microbiol. 77, 4055–4065 (2011).Article 

    Google Scholar 
    Cottrell, M. T. & Kirchman, D. L. Natural assemblages of marine proteobacteria and members of the Cytophaga-Flavobacter cluster consuming low- and high-molecular-weight dissolved organic matter. Appl. Environ. Microbiol. 66, 1692–1697 (2000).Article 

    Google Scholar 
    Poff, K. E., Leu, A. O., Eppley, J. M., Karl, D. M. & DeLong, E. F. Microbial dynamics of elevated carbon flux in the open ocean’s abyss. Proc. Natl Acad. Sci. USA 118, e2018269118 (2021).Article 

    Google Scholar 
    Ducklow, H. in Microbial Ecology of the Oceans (ed. Kirchman, D. L.) Ch. 4, 85–120 (Wiley-Liss, 2000).Herndl, G. J. et al. Contribution of archaea to total prokaryotic production in the deep Atlantic Ocean. Appl. Environ. Microbiol. 71, 2303–2309 (2005).Article 

    Google Scholar 
    Baltar, F., Aristegui, J., Gasol, J. M. & Herndl, G. J. Prokaryotic carbon utilization in the dark ocean: growth efficiency, leucine-to-carbon conversion factors, and their relation. Aquat. Microb. Ecol. 60, 227–232 (2010).Article 

    Google Scholar 
    Edgcomb, V. P. et al. Comparison of Niskin vs. in situ approaches for analysis of gene expression in deep Mediterranean Sea water samples. Deep-Sea Res. II 129, 213–222 (2016).Article 

    Google Scholar 
    Cario, A., Oliver, G. C. & Rogers, K. L. Exploring the deep marine biosphere: challenges, innovations, and opportunities. Front. Earth Sci. 7, 225 (2019).Article 

    Google Scholar 
    Giering, S. L. C. et al. Reconciliation of the carbon budget in the ocean’s twilight zone. Nature 507, 480–483 (2014).Article 

    Google Scholar 
    Simon, M. & Azam, F. Protein content and protein synthesis rates of planktonic marine bacteria. Mar. Ecol. Prog. Ser. 51, 201–213 (1989).Article 

    Google Scholar 
    Gasol, J. M. et al. Mesopelagic prokaryotic bulk and single-cell heterotrophic activity and community composition in the NW Africa-Canary Islands coastal-transition zone. Prog. Oceanogr. 83, 189–196 (2009).Article 

    Google Scholar 
    DeLong, E. F. et al. Community genomics among stratified microbial assemblages in the ocean’s interior. Science 311, 496–503 (2006).Article 

    Google Scholar 
    Teira, E., Reinthaler, T., Pernthaler, A., Pernthaler, J. & Herndl, G. J. Combining catalyzed reporter deposition-fluorescence in situ hybridization and microautoradiography to detect substrate utilization by bacteria and archaea in the deep ocean. Appl. Environ. Microbiol. 70, 4411–4414 (2004).Article 

    Google Scholar 
    Woebken, D., Fuchs, B. M., Kuypers, M. M. M. & Amann, R. Potential interactions of particle-associated anammox bacteria with bacterial and archaeal partners in the Namibian upwelling system. Appl. Environ. Microbiol. 73, 4648–4657 (2007).Article 

    Google Scholar 
    Wand, M. P. Data-based choice of histogram bin width. Am. Stat. 51, 59–64 (1997).
    Google Scholar 
    Acinas, S. G. et al. Deep ocean metagenomes provide insight into the metabolic architecture of bathypelagic microbial communities. Commun. Biol. 4, 604 (2021).Article 

    Google Scholar 
    Sunagawa, S. et al. Structure and function of the global ocean microbiome. Science 348, 1261359 (2015).Article 

    Google Scholar 
    Delmont, T. O. et al. Nitrogen-fixing populations of Planctomycetes and Proteobacteria are abundant in surface ocean metagenomes. Nat. Microbiol. 3, 804–813 (2018).Article 

    Google Scholar 
    Li, D., Liu, C. M., Luo, R., Sadakane, K. & Lam, T. W. MEGAHIT: an ultra-fast single-node solution for large and complex metagenomics assembly via succinct de Bruijn graph. Bioinformatics 31, 1674–1676 (2015).Article 

    Google Scholar 
    Wu, Y. W., Tang, Y. H., Tringe, S. G., Simmons, B. A. & Singer, S. W. MaxBin: an automated binning method to recover individual genomes from metagenomes using an expectation-maximization algorithm. Microbiome 2, 26 (2014).Article 

    Google Scholar 
    Kang, D. D. et al. MetaBAT 2: an adaptive binning algorithm for robust and efficient genome reconstruction from metagenome assemblies. Peerj 7, e7359 (2019).Article 

    Google Scholar 
    Olm, M. R., Brown, C. T., Brooks, B. & Banfield, J. F. dRep: a tool for fast and accurate genomic comparisons that enables improved genome recovery from metagenomes through de-replication. ISME J. 11, 2864–2868 (2017).Article 

    Google Scholar 
    Chaumeil, P. A., Mussig, A. J., Hugenholtz, P. & Parks, D. H. GTDB-Tk: a toolkit to classify genomes with the Genome Taxonomy Database. Bioinformatics 36, 1925–1927 (2020).
    Google Scholar 
    Hyatt, D. et al. Prodigal: prokaryotic gene recognition and translation initiation site identification. BMC Bioinf. 11, 119 (2010).Article 

    Google Scholar 
    Li, W. & Godzik, A. Cd-hit: a fast program for clustering and comparing large sets of protein or nucleotide sequences. Bioinformatics 22, 1658–1659 (2006).Article 

    Google Scholar 
    Eng, J. K., McCormack, A. L. & Yates, J. R. An approach to correlate tandem mass spectral data of peptides with amino acid sequences in a protein database. J. Am. Soc. Mass. Spectrom. 5, 976–989 (1994).Article 

    Google Scholar 
    Elias, J. E. & Gygi, S. P. Target-decoy search strategy for increased confidence in large-scale protein identifications by mass spectrometry. Nat. Methods 4, 207–214 (2007).Article 

    Google Scholar 
    Riffle, M. et al. MetaGOmics: a web-based tool for peptide-centric functional and taxonomic analysis of metaproteomics data. Proteomes 6, 2 (2017).Article 

    Google Scholar 
    Reinthaler, T., van Aken, H. M. & Herndl, G. J. Major contribution of autotrophy to microbial carbon cycling in the deep North Atlantic’s interior. Deep-Sea Res. II 57, 1572–1580 (2010).Article 

    Google Scholar 
    Yokokawa, T., Yang, Y. H., Motegi, C. & Nagata, T. Large-scale geographical variation in prokaryotic abundance and production in meso- and bathypelagic zones of the central Pacific and Southern Ocean. Limnol. Oceanogr. 58, 61–73 (2013).Article 

    Google Scholar 
    Frank, A. H., Garcia, J. A., Herndl, G. J. & Reinthaler, T. Connectivity between surface and deep waters determines prokaryotic diversity in the North Atlantic Deep Water. Environ. Microbiol. 18, 2052–2063 (2016).Article 

    Google Scholar 
    Herndl, G. J., Bayer, B., Baltar, F. & Reinthaler, T. Prokaryotic life in the deep ocean’s water column. Annu. Rev. Mar. Sci. (in the press).Uchimiya, M., Ogawa, H. & Nagata, T. Effects of temperature elevation and glucose addition on prokaryotic production and respiration in the mesopelagic layer of the western North Pacific. J. Oceanogr. 72, 419–426 (2016).Article 

    Google Scholar 
    Antia, A. N. et al. Basin-wide particulate carbon flux in the Atlantic Ocean: regional export patterns and potential for atmospheric CO2 sequestration. Glob. Biogeochem. Cycles 15, 845–862 (2001).Article 

    Google Scholar 
    Behrenfeld, M. J. & Falkowski, P. G. Photosynthetic rates derived from satellite-based chlorophyll concentration. Limnol. Oceanogr. 42, 1–20 (1997).Article 

    Google Scholar  More

  • in

    Integrated taxonomy reveals new threatened freshwater mussels (Bivalvia: Hyriidae: Westralunio) from southwestern Australia

    Genetic variationThe best fitting substitution models for COI codons 1–3 were identified as TN + F + G4, F81 + F + I, and TN + F, respectively. The maximum likelihood (ML) and Bayesian inference (BI) trees showed similar topologies of the main nodes, although the BI tree displayed greater resolution of the ingroup branches (Fig. 1). Furthermore, the BI tree revealed three monophyletic clades, while two of those clades were merged in the ML tree. Two of the three molecular species delimitation methods (ASAP and TCS) recovered three groups in the BI tree as distinct taxa (Fig. 1), corresponding to the three previously described ESUs27,28. The third method (bPTP) recovered between 8 and 43 groups (mean = 28.03) suggesting that there is evidence of additional genetic differentiation within the three groups identified by ASAP and TCS. The outputs of the three methods are provided in the Supplementary information. The molecular diagnosis uncovered several fixed nucleotide differences COI characters for each taxon (Table 1: “W. carteri” I = 10; “W. carteri” II = 3; “W. carteri” III = 5). There were also 13 fixed nucleotide differences in W. carteri for the 16S gene. The remaining two taxa had no fixed nucleotide differences for the 16S gene.Figure 1Phylogenetic trees obtained by maximum likelihood (left) and Bayesian inference (right) analysis of “Westralunio carteri” mtDNA COI sequences, including support values for the major genetic clades [ultrafast bootstrap values (left) and Bayesian posterior probabilities (right)]. Colour coded bars show support for the three major clades by the species delimitation methods (ASAP = dark shade; TCS = lighter shade). Green = WcI = “W. carteri” I; blue = WcIII = “W. carteri” III; red = WcII = “W. carteri” II. Results of bPTP analysis not shown (see supplementary data). Haplotype names correspond to Benson et al.28. Outgroup taxa are Velesunio ambiguus (Philippi, 1847) (Hyriidae: Velesunioninae) and Cucumerunio novaehollandiae (Gray, 1834) (Hyriidae: Hyriinae: Hyridellini).Full size imageTable 1 Molecular diagnoses of “Westralunio carteri” Evolutionarily Significant Units (ESUs) from southwestern Australia (after Bolotov et al.122 with reanalysis of data from Klunzinger et al.27 and Benson et al.28).Full size tableVariation in shell morphologyBased on results from analyses of variances (ANOVAs), shells of “W. carteri” I were significantly larger (for size metrics total length (TL), maximum height (MH), beak height (BH) and beak length (BL)) and more elongated (i.e., had a lower maximum height index (MHI)) than shells of “W. carteri” II and “W. carteri” II + III combined (Table 2). However, there was no difference in size or shape metrics between “W. carteri” I and “W. carteri” III (Table 2). The lack of significant differences in beak height index (BHI) and beak length index (BLI) among any of the taxa (Table 2) indicates that wing and anterior shell development was not discernibly different between any of the ESUs.Table 2 Shell size metrics [mm], shape indices [%] and scores for the first two principal components (PC) obtained by Principal Component Analysis of shape indices and 18 Fourier coefficients generated by Fourier Shape Analysis for each “Westralunio carteri” species and subspecies-level Evolutionarily Significant Units (ESUs): n, number of specimens measured; minimum (min) to maximum (max) and mean (± standard error (SE)).Full size tableThis pattern was partly confirmed in the principal component analysis (PCA) of these three shell shape indices, where PC1, largely explained by variation in BLI (Fig. 2A), did not differ between the two species (i.e., “W. carteri” I vs. “W. carteri” II + III) or among the three taxa (Table 2). The PC2, largely explained by variation in MHI and BHI (Fig. 2A), differed significantly between “W. carteri” I and “W. carteri” II (Table 2). Accordingly, 70% (70% jack-knifed) of specimens were assigned to the correct species in the corresponding discriminant analysis (DA), whilst this was true for only 55% (54%) at the MOTU-level.Figure 2Scatterplots of the first two PC axes obtained by PCA on (A) calculated shape indices based on shell measurements, and (B) 18 Fourier coefficients for “Westralunio carteri” I, “W. carteri” II and “W. carteri” III. 95% Confidence Intervals are displayed at the species level, i.e., for “W. carteri” I (full line) and “W. carteri” II + III (dashed line). Extreme shell outlines in (B) are depicted to visualise trends in sagittal shell shape, along PC axes.Full size imageThe difference in shell elongation between “W. carteri” I and “W. carteri” II was confirmed by Fourier shape analysis. As visualised by synthetic outlines in Fig. 2B, shell elongation is expressed along the PC1 (explaining 15% of total variation in Fourier coefficients). The PC1 as well as PC2 scores differed significantly between the two species (i.e., “W. carteri” I vs. “W. carteri” II + III) as well as between “W. carteri” I and “W. carteri” II, respectively (Table 2). Combined with synthetic outlines, this indicated a tendency towards a more elongated, somewhat wedge-shaped shell in “W. carteri” I, whilst “W. carteri” II shells tended to be relatively high with a stout anterior margin (Fig. 2B). An analysis of similarities (ANOSIM) analysis on all Fourier coefficients revealed no significant difference between the two species (i.e., “W. carteri” I vs. “W. carteri” II + III; ANOSIM: R = − 0.018, p = 0.097), but did indicate a significant difference between the three ESUs (ANOSIM: R = 0.0625, p = 0.0051). Specifically, “W. carteri” I differed significantly from “W. carteri” II (Bonferroni-corrected p = 0.0009). Only 66% and 65% (62% and 62% jack-knifed) of specimens were assigned to the correct species and taxon in DAs on that dataset, respectively.Taxonomic accountsClass: Bivalvia Linnaeus, 175831.Subclass: Autobranchia Grobben, 189432.Infraclass: Heteroconchia Gray, 185433.Cohort: Palaeoheterodonta Newell, 196534.Order: Unionida Gray, 185433 in Bouchet & Rocroi, 201035.Superfamily: Unionoidea Rafinesque, 182036.Family: Hyriidae Parodiz & Bonetto 196337.Genus: Westralunio Iredale, 19349.Type species: Westralunio ambiguus carteri Iredale, 19349 (by original designation).Redescription: Westralunio carteri (Iredale, 1934)SynonymyUnio australis Lamarck38: Menke39, p. 38, specimen 219. (Non Unio australis Lamarck, 181938).Unio moretonicus Reeve40: Smith41, p. 3, pl. iv, Fig. 2. (misidentified reference to Unio moretonicus Reeve, 186540).Hyridella australis (Lam.38): Cotton & Gabriel42 (in part), p. 156. (misidentified reference to Unio australis Lamarck, 181938).Hyridella ambigua (Philippi26): Cotton & Gabriel42 (in part), p. 157. (misidentified reference to Unio ambiguus Philippi, 184726).Westralunio ambiguus carteri: Iredale, 19349, p. 62.Westralunio ambiguus (Philippi26): Iredale9, p. 62, pl. iii, Fig. 8, pl. iv, Fig. 8. (Non Unio ambiguus Phil. 184726), Iredale43, p. 190.Centralhyria angasi subjecta Iredale, 19349, p. 67 (in part), Iredale43, p. 190.Westralunio carteri Iredale9: McMichael & Hiscock10pl. viii, Figs. 1, 2, 3, 4, 5, 6 and 7, pl. xvii, Figs. 4, 5.Type materialLectotype: AMS C.61724 (Fig. 3A) Westralunio ambiguus carteri Iredale, 19349.Figure 3(A) Westralunio ambiguus carteri Iredale, 1934, Lectotype: Victoria Reservoir, Darling Range, 12 mi E of Perth, AMS C.061724. Detail of fusion in anterior muscle scars from either valve represented by dashed lines and black polygons. Bottom image showing detail of hinge teeth. Photos provided with permission by Dr Mandy Reid, AMS. (B) Valves and detail of sculptured umbo of a juvenile W. carteri from Yule Brook, Western Australia, UMZC 2013.2.9. Photo by Dr Michael W. Klunzinger. (C) Glochidia of W. carteri from Canning River, Western Australia. Photo by Dr Michael W. Klunzinger.Full size imageParalectotypes: AMS C.170635 Westralunio ambiguus carteri Iredale, 19349 (n = 4).Type locality: Victoria Reservoir, Darling Range, 12 miles east of Perth, Western Australia (Fig. 4A).Figure 4(A) Victoria Reservoir, Canning River, near Perth, Western Australia, type locality for W. carteri. Photo by Corey Whisson. (B) Goodga River, Western Australia, type locality for W. inbisi inbisi, at vertical slot fishway where holotype of W. inbisi inbisi was collected from. Photo provided with permission by Dr Stephen J. Beatty. (C) Margaret River, Western Australia, type locality for W. inbisi meridiemus, at Canebreak Pool. Photo by Dr Michael W. Klunzinger.Full size imageLectotype: BMNH 1840–10-21–29 Centralhyria angasi subjecta Iredale (selected by McMichael & Hiscock10).Type locality: Avon River, Western Australia.Material examined for redescription: For W. carteri (= “W. carteri” I), molecular data examined included 52 and 61 individual COI mtDNA and 16S rDNA sequences, respectively, for species delimitation. Additionally, Fourier shell shape outline analysis and traditional shell morphometric measurements were examined from 238 and 290 individuals, respectively. Complete details on all specimens examined are provided in Supplementary Table S1.ZooBank registration: urn:lsid:zoobank.org:act:6B740F4D-40C3-4D6A-8938-B0FD7FD1F6D7.Etymology: The species name carteri is most likely named after the surname of the collector who provided original type specimens to the Australian Museum, although Iredale9 did not specify this as the case. We have applied ICZN Articles 46.1 and 47.144, designating W. carteri as the nominotypical species.Revised diagnosis: Specimens of W. carteri are distinguished from other Australian Westralunio taxa by having shell series that are significantly larger and more elongated than Westralunio inbisi inbisi subsp. nov., but not different from Westralunio inbisi meridiemus subsp. nov. The species has 10 diagnostic nucleotides at COI (57 G, 117 T, 210 G, 249 T, 255 C, 345 G, 423 T, 447 T, 465 A, 499 T) and 13 at 16S (137 T, 155 C, 228 C, 229 T, 260 G, 290 A, 305 G, 307 T, 310 A, 311 C, 321 T, 330 A, 460 A), which differentiate it from its sister taxa, W. inbisi inbisi and W. inbisi meridiemus (each described below) using ASAP and TCS species delimitation models.RedescriptionThis species is of the ESU “W. carteri” I27,28.Shell morphology: Shells of relatively small to medium size, generally less than 70 mm in length, but to a maximum length of approximately 100 mm10,45, MHI 46–89%; anterior portion of shell with moderate development, BLI 22–49%; larger shells with abraded umbos scarcely winged; wing development variable, generally decreasing with size, BHI 76–104% (Table 2). Shell outline oblong-ovate to rounded; posterior end obliquely to squarely truncate, anterior end round; ventral edge slightly curved, nearly straight in larger specimens; hinge line curved, hinge strong. Umbos usually abraded in specimens  > 20 mm in length; unabraded umbos with distinctive v- or w-shaped plicated sculpturing (Fig. 3B and Zieritz et al.46). Shell substance typically thick; shells of medium width with pronounced posterior ridge; periostracum smooth, dark brown to reddish, with fine growth lines. Pallial line less developed in smaller specimens and prominent only in large specimens (e.g.,  > 60 mm TL). Lateral teeth longer and blade-like, slightly serrated to smooth and singular in left valve, fitting into deep groove in right valve; pseudocardinal tooth in right valve coarsely serrated, thick, and erect, fitting into deeply grooved socket in left valve. Anterior muscle scars well impressed and anchored deeply in larger specimens; anterior retractor pedis and protractor pedis scars both small and fused with adductor muscle scar; posterior muscle scars lightly impressed; dorsal muscle scars usually with two or three deep pits anchored to internal umbo region.Anatomy: Supra-anal opening absent, siphons of moderate size, not prominent but protrude beyond shell margin in actively filtering live specimens, pigmented dark brown with mottled lighter brown to orange splotches; inhalant siphon aperture about 1.5 times size of exhalant and bearing 2–4 rows of internal papillae (Fig. 5A); ctenidial diaphragm relatively long and perforated. Outer lamellae of outer ctenidia completely fused to mantle, inner lamellae of inner ctenidia fused to visceral mass then united to form diaphragm; palps relatively small, usually semilunar in shape; marsupium well developed as a distinctive swollen interlamellar space in the middle third of the inner ctenidium of females. Outer ctenidia in both sexes thin, with numerous, short intrafilamentary junctions and few, irregular interlamellar junctions; in females similar, but marsupium has numerous, tightly packed, well-developed interlamellar junctions. Thus, brooding in females is endobranchous.Figure 5Live specimens of actively filtering freshwater mussels in the burrowed position. (A) Westralunio carteri (Iredale, 1934), Canning River at Kelmscott, Western Australia, inhalant siphon with 2–4 rows of papillae oriented toward substrate. Photo by Dr Michael W. Klunzinger. (B) Westralunio inbisi meridiemus subsp. nov., Canebreak Pool, Margaret River, Western Australia; inhalant siphon edges lined with protruding papillae facing towards water surface, away from substrate. Photo by Dr Michael W. Klunzinger.Full size imageLife history: Sexes are separate in W. carteri, and hermaphroditism appears to be rare47,48,49. Males and females both produce gametes year-round but brooding of glochidia appears to be seasonal and ‘tachyticitc’ (i.e., as defined by Bauer & Wächtler19, fertilisation and embryonic development occurring in late winter/early spring and glochidia release in early summer)50. Glochidia are released within vitelline membranes, embedded in mucus which extrude from exhalant siphons of females (i.e., ‘amorphous mucus conglutinates’) during spring/summer. Glochidia attach to host fishes and live parasitically on fins, gills or body surfaces for 3–4 weeks while undergoing metamorphosis to the juvenile stage. Host fishes which have been shown to support glochidia metamorphosis to the juvenile stage in the laboratory include Afurcagobius suppositus (Sauvage, 188051), Gambusia holbrooki (Girard, 185952), Nannoperca vitttata (Castelnau, 187353), Pseudogobius olorum (Sauvage, 188051) and Tandanus bostocki Whitley, 194454 but not Carassisus auratus Linnaeus, 175831 or Geophagus brasiliensis (Quoy & Gaimard, 1824 More

  • in

    Local-scale feedbacks influencing cold-water coral growth and subsequent reef formation

    Henry, L.-A. & Roberts, J. M. Biodiversity and ecological composition of macrobenthos on cold-water coral mounds and adjacent off-mound habitat in the bathyal Porcupine Seabight, NE Atlantic. Deep Sea Res. I(54), 654–672 (2007).
    Google Scholar 
    Buhl-Mortensen, L. et al. First observations of the structure and megafaunal community of a large Lophelia reef on the Ghanaian shelf (the Gulf of Guinea). Deep Sea Res. II(137), 148–156 (2017).
    Google Scholar 
    Price, D. M. et al. Using 3D photogrammetry from ROV video to quantify cold-water coral reef structural complexity and investigate its influence on biodiversity and community assemblage. Coral Reefs 38, 1007–1021 (2019).
    Google Scholar 
    Roberts, J. M., Wheeler, A. J. & Freiwald, A. Reefs of the deep: the biology and geology of cold-water coral ecosystems. Science 312, 543–547 (2006).CAS 
    PubMed 

    Google Scholar 
    Henry, L. A., Nizinski, M. S. & Ross, S. W. Occurrence and biogeography of hydroids (Cnidaria: Hydrozoa) from deep-water coral habitats off the southeastern United States. Deep. Res. I(55), 788–800 (2008).
    Google Scholar 
    Henry, L.-A. & Roberts, J. M. Global Biodiversity in Cold-Water Coral Reef Ecosystems. In Marine Animal Forests (eds Rossi, S. et al.) 1–21 (Springer, 2016). https://doi.org/10.1007/978-3-319-17001-5_6-1.Chapter 

    Google Scholar 
    De Mol, B. et al. Large deep-water coral banks in the Porcupine Basin, southwest of Ireland. Mar. Geol. 188, 193–231 (2002).
    Google Scholar 
    Dorschel, B., Hebbeln, D., Rüggeberg, A., Dullo, W. C. & Freiwald, A. Growth and erosion of a cold-water coral covered carbonate mound in the Northeast Atlantic during the Late Pleistocene and Holocene. Earth Planet. Sci. Lett. 233, 33–44 (2005).CAS 

    Google Scholar 
    Hebbeln, D., Van Rooij, D. & Wienberg, C. Good neighbours shaped by vigorous currents: Cold-water coral mounds and contourites in the North Atlantic. Mar. Geol. 378, 171–185 (2016).
    Google Scholar 
    Wheeler, A. J. et al. Morphology and environment of cold-water coral carbonate mounds on the NW European margin. Int. J. Earth Sci. 96, 37–56 (2007).CAS 

    Google Scholar 
    Lo Iacono, C., Savini, A. & Basso, D. Cold-water carbonate bioconstructions. in Submarine Geomorphology, 425–455 (Springer, 2018).Hebbeln, D. Highly variable submarine landscapes in the Alborán sea created by cold-water corals. In Mediterranean Cold-Water Corals: Past, Present and Future (eds Orejas, C. & Jiménez, C.) 61–65 (Springer, 2019). https://doi.org/10.1007/978-3-319-91608-8_8.Chapter 

    Google Scholar 
    Addamo, A. M. et al. Merging scleractinian genera: The overwhelming genetic similarity between solitary Desmophyllum and colonial Lophelia. BMC Evol. Biol. 16, 1–17 (2016).
    Google Scholar 
    Wienberg, C. & Titschack, J. Framework-forming scleractinian cold-water corals through space and time: A late quaternary north atlantic perspective. in Marine Animal Forests 1–34 (Springer, 2017). https://doi.org/10.1007/978-3-319-17001-5_16-1Maier, C., Weinbauer, M. G. & Gattuso, J.-P. Fate of mediterranean scleractinian cold-water corals as a result of global climate change: A synthesis. In Mediterranean Cold-Water Corals: Past, Present and Future (eds Orejas, C. & Jiménez, C.) 517–529 (Springer, 2019). https://doi.org/10.1007/978-3-319-91608-8_44.Chapter 

    Google Scholar 
    Reynaud, S. & Ferrier-Pagès, C. Biology and ecophysiology of mediterranean cold-water corals. In Mediterranean Cold-Water Corals: Past, Present and Future (eds Orejas, C. & Jiménez, C.) 391–404 (Springer, 2019). https://doi.org/10.1007/978-3-319-91608-8_35.Chapter 

    Google Scholar 
    Hennige, S. J. et al. Using the Goldilocks principle to model coral ecosystem engineering. Proc. R. Soc. B Biol. Sci. 288, 20211260 (2021).CAS 

    Google Scholar 
    LoIacono, C. et al. The West Melilla cold water coral mounds, Eastern Alboran Sea: Morphological characterization and environmental context. Deep Sea Res. II(99), 316–326 (2014).
    Google Scholar 
    Mortensen, P. B., Hovland, T., Fosså, J. H. & Furevik, D. M. Distribution, abundance and size of Lophelia pertusa coral reefs in mid-Norway in relation to seabed characteristics. J. Mar. Biol. Assoc. 81, 581–597 (2001).
    Google Scholar 
    Mienis, F. et al. Hydrodynamic controls on cold-water coral growth and carbonate-mound development at the SW and SE Rockall Trough Margin, NE Atlantic. Ocean. Deep. Res. I(54), 1655–1674 (2007).
    Google Scholar 
    Davies, A. J. et al. Downwelling and deep-water bottom currents as food supply mechanisms to the cold-water coral Lophelia pertusa (Scleractinia) at the Mingulay Reef Complex. Limnol. Oceanogr. 54, 620–629 (2009).
    Google Scholar 
    Mohn, C. et al. Linking benthic hydrodynamics and cold-water coral occurrences: A high-resolution model study at three cold-water coral provinces in the NE Atlantic. Prog. Oceanogr. 122, 92–104 (2014).
    Google Scholar 
    Mienis, F. et al. Cold-water coral growth under extreme environmental conditions, the Cape Lookout area, NW Atlantic. Biogeosciences 11, 2543–2560 (2014).
    Google Scholar 
    Grasmueck, M. et al. Autonomous underwater vehicle (AUV) mapping reveals coral mound distribution, morphology, and oceanography in deep water of the Straits of Florida. Geophys. Res. Lett. 33, L23616 (2006).
    Google Scholar 
    Correa, T. B. S., Eberli, G. P., Grasmueck, M., Reed, J. K. & Correa, A. M. S. Genesis and morphology of cold-water coral ridges in a unidirectional current regime. Mar. Geol. 326–328, 14–27 (2012).
    Google Scholar 
    Lavaleye, M. et al. Cold-water corals on the tisler reef: Preliminary observations on the dynamic reef environment. Oceanography 22, 76–84 (2009).
    Google Scholar 
    Mortensen, P. B. et al. Seascape description of anunusual coral reef area off Vesteraålen, Northern Norway. in 4th International Symposium on deep-sea corals. (2008).Cathalot, C. et al. Cold-water coral reefs and adjacent sponge grounds: Hotspots of benthic respiration and organic carbon cycling in the deep sea. Front. Mar. Sci. 2, 37 (2015).
    Google Scholar 
    Buhl-Mortensen, P. & Sundahl, H. Environmental control of cold-water coral reef morphology. in 7th International Symposium on deep-sea corals. (2019).van der Kaaden, A.-S., van Oevelen, D., Rietkerk, M., Soetaert, K. & van de Koppel, J. Spatial self-organization as a new perspective on cold-water coral mound development. Front. Mar. Sci. 7, 631 (2020).
    Google Scholar 
    Buhl-Mortensen, L. et al. Biological structures as a source of habitat heterogeneity and biodiversity on the deep ocean margins. Mar. Ecol. 31, 21–50 (2010).
    Google Scholar 
    Jones, C. G., Lawton, J. H. & Shachak, M. Organisms as ecosystem engineers. Oikos 69, 373–386 (1994).
    Google Scholar 
    Mienis, F., Bouma, T., Witbaard, R., van Oevelen, D. & Duineveld, G. Experimental assessment of the effects of coldwater coral patches on water flow. Mar. Ecol. Prog. Ser. 609, 101–117 (2019).CAS 

    Google Scholar 
    van der Kaaden, A.-S. et al. Feedbacks between hydrodynamics and cold-water coral mound development. Deep Sea Res. I 178, 103641 (2021).
    Google Scholar 
    Mortensen, P. B., Hovland, M., Brattegard, T. & Farestveit, R. Deep water bioherms of the scleractinian coral Lophelia pertusa (L.) at 64° n on the norwegian shelf: Structure and associated megafauna. Sarsia 80, 145–158 (1995).
    Google Scholar 
    Corbera, G. et al. Ecological characterisation of a Mediterranean cold-water coral reef: Cabliers Coral Mound Province (Alboran Sea, western Mediterranean). Prog. Oceanogr. 175, 245–262 (2019).
    Google Scholar 
    Kano, A. et al. Age constraints on the origin and growth history of a deep-water coral mound in the northeast Atlantic drilled during Integrated Ocean Drilling Program Expedition 307. Geology 35, 1051–1054 (2007).CAS 

    Google Scholar 
    Douarin, M. et al. Growth of north-east Atlantic cold-water coral reefs and mounds during the Holocene: A high resolution U-series and 14C chronology. Earth Planet. Sci. Lett. 375, 176–187 (2013).CAS 

    Google Scholar 
    Orejas, C., Gori, A. & Gili, J. M. Growth rates of live Lophelia pertusa and Madrepora oculata from the Mediterranean Sea maintained in aquaria. Coral Reefs 27, 255–255 (2008).
    Google Scholar 
    Orejas, C. et al. Long-term growth rates of four Mediterranean cold-water coral species maintained in aquaria. Mar. Ecol. Prog. Ser. 429, 57–65 (2011).
    Google Scholar 
    Lartaud, F., Mouchi, V., Chapron, L., Meistertzheim, A.-L. & Le Bris, N. Growth Patterns of Mediterranean Calcifying Cold-Water Corals. in Mediterranean Cold-Water Corals: Past, Present and Future 405–422 (2019). https://doi.org/10.1007/978-3-319-91608-8_36.Büscher, J. V. et al. In situ growth and bioerosion rates of Lophelia pertusa in a Norwegian fjord and open shelf cold-water coral habitat. PeerJ 2019, 1–10 (2019).
    Google Scholar 
    Form, A. U. & Riebesell, U. Acclimation to ocean acidification during long-term CO2 exposure in the cold-water coral Lophelia pertusa. Glob. Chang. Biol. 18, 843–853 (2012).
    Google Scholar 
    Maier, C., Watremez, P., Taviani, M., Weinbauer, M. G. & Gattuso, J. P. Calcification rates and the effect of ocean acidification on Mediterranean cold-water corals. Proc. R. Soc. B Biol. Sci. 279, 1716–1723 (2012).CAS 

    Google Scholar 
    Lunden, J. J., McNicholl, C. G., Sears, C. R., Morrison, C. L. & Cordes, E. E. Acute survivorship of the deep-sea coral Lophelia pertusa from the Gulf of Mexico under acidification, warming, and deoxygenation. Front. Mar. Sci. 1, 78 (2014).
    Google Scholar 
    Gori, A., Reynaud, S., Orejas, C., Gili, J. M. & Ferrier-Pagès, C. Physiological performance of the cold-water coral Dendrophyllia cornigera reveals its preference for temperate environments. Coral Reefs 33, 665–674 (2014).
    Google Scholar 
    Huvenne, V. A. I. et al. Sediment dynamics and palaeo-environmental context at key stages in the Challenger cold-water coral mound formation: Clues from sediment deposits at the mound base. Deep. Res. I(56), 2263–2280 (2009).
    Google Scholar 
    Bartzke, G. et al. Investigating the prevailing hydrodynamics around a cold-water coral colony using a physical and a numerical approach. Front. Mar. Sci. 8, 3304 (2021).
    Google Scholar 
    Downs, C. A. et al. Cellular diagnostics and coral health: Declining coral health in the Florida Keys. Mar. Pollut. Bull. 51, 558–569 (2005).CAS 
    PubMed 

    Google Scholar 
    Ayala, A., Muñoz, M. F. & Argüelles, S. Lipid peroxidation: Production, metabolism, and signaling mechanisms of malondialdehyde and 4-hydroxy-2-nonenal. Oxid. Med. Cell. Long. 2014, 1–10 (2014).CAS 

    Google Scholar 
    Oh, T. J., Kim, I. G., Park, S. Y., Kim, K. C. & Shim, H. W. NAD-dependent malate dehydrogenase protects against oxidative damage in Escherichia coli K-12 through the action of oxaloacetate. Environ. Toxicol. Pharmacol. 11, 9–14 (2002).CAS 
    PubMed 

    Google Scholar 
    Dade, L., Hogg, A. & Boudreau, B. Physics of Flow Above the Sediment-Water Interface (Oxford University Press, 2001).
    Google Scholar 
    Gass, S. E. & Roberts, J. M. The occurrence of the cold-water coral Lophelia pertusa (Scleractinia) on oil and gas platforms in the North Sea: Colony growth, recruitment and environmental controls on distribution. Mar. Pollut. Bull. 52, 549–559 (2006).CAS 
    PubMed 

    Google Scholar 
    Brooke, S. & Young, C. M. In situ measurement of survival and growth of Lophelia pertusa in the northern Gulf of Mexico. Mar. Ecol. Prog. Ser. 397, 153–161 (2009).
    Google Scholar 
    Lartaud, F. et al. A new approach for assessing cold-water coral growth in situ using fluorescent calcein staining. Aquat. Living Resour. 26, 187–196 (2013).
    Google Scholar 
    Sebens, K. P., Witting, J. & Helmuth, B. Effects of water flow and branch spacing on particle capture by the reef coral Madracis mirabilis (Duchassaing and Michelotti). J. Exp. Mar. Bio. Ecol. 211, 1–28 (1997).
    Google Scholar 
    Sebens, K. P., Grace, S. P., Helmuth, B., Maney, E. J. Jr. & Miles, J. S. Water flow and prey capture by three scleractinian corals, Madracis mirabilis, Montastrea cavernosa and Porites porites, in a field enclosure. Mar. Biol. 131, 347–360 (1998).
    Google Scholar 
    Purser, A., Larsson, A. I., Thomsen, L. & van Oevelen, D. The influence of flow velocity and food concentration on Lophelia pertusa (Scleractinia) zooplankton capture rates. J. Exp. Mar. Bio. Ecol. 395, 55–62 (2010).
    Google Scholar 
    Orejas, C. et al. The effect of flow speed and food size on the capture efficiency and feeding behaviour of the cold-water coral Lophelia pertusa. J. Exp. Mar. Bio. Ecol. 481, 34–40 (2016).
    Google Scholar 
    Duineveld, G. C. A. et al. Spatial and tidal variation in food supply to shallow cold-water coral reefs of the Mingulay Reef complex (Outer Hebrides, Scotland). Mar. Ecol. Prog. Ser. 444, 97–115 (2012).
    Google Scholar 
    De Clippele, L. H. et al. The effect of local hydrodynamics on the spatial extent and morphology of cold-water coral habitats at Tisler Reef, Norway. Coral Reefs 37, 253–266 (2018).PubMed 

    Google Scholar 
    Jokiel, P. L. Effects of water motion on reef corals. J. Exp. Mar. Biol. Ecol. 35, 87–97 (1978).
    Google Scholar 
    Shashar, N., Cohen, Y. & Loya, Y. Extreme diel fluctuations of oxygen in diffusive boundary layers surrounding stony corals. Biol. Bull. 185, 455–461 (1993).CAS 
    PubMed 

    Google Scholar 
    Finelli, C. M., Helmuth, B. S. T., Pentcheff, N. D. & Wethey, D. S. Water flow influences oxygen transport and photosynthetic efficiency in corals. Coral Reefs 25, 47–57 (2006).
    Google Scholar 
    Atkinson, M. J. & Bilger, R. W. Effects of water velocity on phosphate uptake in coral reef-hat communities. Limnol. Oceanogr. 37, 273–279 (1992).CAS 

    Google Scholar 
    Mass, T., Genin, A., Shavit, U., Grinstein, M. & Tchernov, D. Flow enhances photosynthesis in marine benthic autotrophs by increasing the efflux of oxygen from the organism to the water. Proc. Natl. Acad. Sci. 107, 2527–2531 (2010).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    Comeau, S., Edmunds, P. J., Lantz, C. A. & Carpenter, R. C. Water flow modulates the response of coral reef communities to ocean acidification. Sci. Rep. 4, 6681 (2014).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    Larsson, A., Lundälv, T. & van Oevelen, D. Skeletal growth, respiration rate and fatty acid composition in the cold-water coral Lophelia pertusa under varying food conditions. Mar. Ecol. Prog. Ser. 483, 169–184 (2013).
    Google Scholar 
    Baussant, T., Nilsen, M., Ravagnan, E., Westerlund, S. & Ramanand, S. Physiological responses and lipid storage of the coral Lophelia pertusa at varying food density. J. Toxicol. Environ. Health. A 80, 266–284 (2017).CAS 
    PubMed 

    Google Scholar 
    Bouma, T. J. et al. Spatial flow and sedimentation patterns within patches of epibenthic structures: Combining field, flume and modelling experiments. Cont. Shelf Res. 27, 1020–1045 (2007).
    Google Scholar 
    Brooke, S. D., Holmes, M. W. & Young, C. M. Sediment tolerance of two different morphotypes of the deep-sea coral Lophelia pertusa from the Gulf of Mexico. Mar. Ecol. Prog. Ser. 390, 137–144 (2009).
    Google Scholar 
    Bøe, R. et al. Giant sandwaves in the Hola glacial trough off Vesterålen, North Norway. Mar. Geol. 267, 36–54 (2009).
    Google Scholar 
    Huvenne, V. A. I. et al. The Magellan mound province in the Porcupine Basin. Int. J. Earth Sci. 96, 85–101 (2007).CAS 

    Google Scholar 
    De Haas, H. et al. Morphology and sedimentology of (clustered) cold-water coral mounds at the south Rockall Trough margins, NE Atlantic Ocean. Facies 55, 1–26 (2009).
    Google Scholar 
    Lim, A., Huvenne, V. A. I., Vertino, A., Spezzaferri, S. & Wheeler, A. J. New insights on coral mound development from groundtruthed high-resolution ROV-mounted multibeam imaging. Mar. Geol. 403, 225–237 (2018).
    Google Scholar 
    Olariaga, A., Gori, A., Orejas, C. & Gili, J. M. Development of an autonomous aquarium system for maintaining deep corals. Oceanography 22, 44–45 (2009).
    Google Scholar 
    Davies, A. J. et al. Short-term environmental variability in cold-water coral habitat at Viosca Knoll, Gulf of Mexico. Deep Sea Res. I(57), 199–212 (2010).
    Google Scholar 
    Mienis, F. et al. The influence of near-bed hydrodynamic conditions on cold-water corals in the Viosca Knoll area, Gulf of Mexico. Deep Sea Res. I(60), 32–45 (2012).
    Google Scholar 
    Flo, E., Garcés, E., Manzanera, M. & Camp, J. Coastal inshore waters in the NW Mediterranean: Physicochemical and biological characterization and management implications. Estuar. Coast. Shelf Sci. 93, 279–289 (2011).CAS 

    Google Scholar 
    Davies, P. S. Short-term growth measurements of corals using an accurate buoyant weighing technique. Mar. Biol. 101, 389–395 (1989).
    Google Scholar 
    R Core Team. R: A Language and Environment for Statistical Computing. (R Core Team, 2018).Bradford, M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem. 72, 248–254 (1976).CAS 
    PubMed 

    Google Scholar 
    Thérond, P., Auger, J., Legrand, A. & Jouannet, P. α-tocopherol in human spermatozoa and seminal plasma: Relationships with motility, antioxidant enzymes and leukocytes. Mol. Hum. Reprod. 2, 739–744 (1996).PubMed 

    Google Scholar 
    Beers, R. F. & Sizer, I. W. A spectrophotometric method for measuring the breakdown of hydrogen peroxide by catalase. J. Biol. Chem. 195, 133–140 (1952).CAS 
    PubMed 

    Google Scholar 
    Kalghatgi, S. et al. Bactericidal antibiotics induce mitochondrial dysfunction and oxidative damage in mammalian cells. Sci. Transl. Med. 5, 1–10 (2013).
    Google Scholar  More