More stories

  • in

    Temperatures that sterilize males better match global species distributions than lethal temperatures

    1.Pecl, G. T. et al. Biodiversity redistribution under climate change: impacts on ecosystems and human well-being. Science 355, eaai9214 (2017).Article 

    Google Scholar 
    2.Kearney, M. & Porter, W. Mechanistic niche modelling: combining physiological and spatial data to predict species’ ranges. Ecol. Lett. 12, 334–350 (2009).Article 

    Google Scholar 
    3.Nowakowski, A. J. et al. Thermal biology mediates responses of amphibians and reptiles to habitat modification. Ecol. Lett. 21, 345–355 (2018).Article 

    Google Scholar 
    4.Metelmann, S. et al. The UK’s suitability for Aedes albopictus in current and future climates. J. R. Soc. Interface 16, 20180761 (2019).CAS 
    Article 

    Google Scholar 
    5.Kellermann, V. et al. Upper thermal limits of Drosophila are linked to species distributions and strongly constrained phylogenetically. Proc. Natl Acad. Sci. USA 109, 16228–16233 (2012).CAS 
    Article 

    Google Scholar 
    6.Lancaster, L. T. & Humphreys, A. M. Global variation in the thermal tolerances of plants. Proc. Natl Acad. Sci. USA 117, 13580–13587 (2020).CAS 
    Article 

    Google Scholar 
    7.Sunday, J. M. et al. Thermal-safety margins and the necessity of thermoregulatory behavior across latitude and elevation. Proc. Natl Acad. Sci. USA 111, 5610–5615 (2014).CAS 
    Article 

    Google Scholar 
    8.Rezende, E. L., Bozinovic, F., Szilàgyi, A. & Santos, M. Predicting temperature mortality and selection in natural Drosophila populations. Science 369, 1242–1245 (2020).CAS 
    Article 

    Google Scholar 
    9.Jørgensen, L. B., Malte, H. & Overgaard, J. How to assess Drosophila heat tolerance: unifying static and dynamic tolerance assays to predict heat distribution limits. Funct. Ecol. 33, 629–642 (2019).Article 

    Google Scholar 
    10.Rezende, E. L., Castañeda, L. E. & Santos, M. Tolerance landscapes in thermal ecology. Funct. Ecol. 28, 799–809 (2014).Article 

    Google Scholar 
    11.Terblanche, J. S. & Hoffmann, A. A. Validating measurements of acclimation for climate change adaptation. Curr. Opin. Insect Sci. 41, 7–16 (2020).Article 

    Google Scholar 
    12.Walsh, B. S. et al. The impact of climate change on fertility. Trends Ecol. Evol. 34, 249–259 (2019).Article 

    Google Scholar 
    13.Sage, T. L. et al. The effect of high temperature stress on male and female reproduction in plants. Field Crops Res. 182, 30–42 (2015).Article 

    Google Scholar 
    14.Sales, K. et al. Experimental heatwaves compromise sperm function and cause transgenerational damage in a model insect. Nat. Commun. 9, 4771 (2018).Article 

    Google Scholar 
    15.Porcelli, D., Gaston, K. J., Butlin, R. K. & Snook, R. R. Local adaptation of reproductive performance during thermal stress. J. Evol. Biol. 30, 422–429 (2016).Article 

    Google Scholar 
    16.Saxon, A. D., O’Brien, E. K. & Bridle, J. R. Temperature fluctuations during development reduce male fitness and may limit adaptive potential in tropical rainforest Drosophila. J. Evol. Biol. 31, 405–415 (2018).CAS 
    Article 

    Google Scholar 
    17.Breckels, R. D. & Neff, B. D. The effects of elevated temperature on the sexual traits, immunology and survivorship of a tropical ectotherm. J. Exp. Biol. 216, 2658–2664 (2013).Article 

    Google Scholar 
    18.Paxton, C. W., Baria, M. V. B., Weis, V. M. & Harii, S. Effect of elevated temperature on fecundity and reproductive timing in the coral Acropora digitifera. Zygote 24, 511–516 (2016).Article 

    Google Scholar 
    19.Hurley, L. L., McDiarmid, C. S., Friesen, C. R., Griffith, S. C. & Rowe, M. Experimental heatwaves negatively impact sperm quality in the zebra finch. Proc. R. Soc. Lond. B 285, 20172547 (2018).
    Google Scholar 
    20.Yogev, L. et al. Seasonal variations in pre‐ and post‐thaw donor sperm quality. Hum. Reprod. 19, 880–885 (2004).CAS 
    Article 

    Google Scholar 
    21.Terblanche, J. S., Deere, J. A., Clusella Trullas, S., Janion, C. & Chown, S. L. Critical thermal limits depend on methodological context. Proc. R. Soc. Lond. B 274, 2935–2942 (2007).
    Google Scholar 
    22.Ives, A. R. R2s for correlated data: phylogenetic models, LMMs, and GLMMs. Syst. Biol. 68, 234–251 (2019).Article 

    Google Scholar 
    23.Dillon, M. E., Wang, G., Garrity, P. A. & Huey, R. B. Thermal preference in Drosophila. J. Therm. Biol. 34, 109–119 (2009).Article 

    Google Scholar 
    24.Tratter-Kinzner, M. et al. Is temperature preference in the laboratory ecologically relevant for the field? The case of Drosophila nigrosparsa. Glob. Ecol. Conserv. 18, e00638 (2019).Article 

    Google Scholar 
    25.van Heerwaarden, B. & Sgrò, C. M. Male fertility thermal limits predict vulnerability to climate warming. Nat. Commun. 12, 2214 (2021).CAS 
    Article 

    Google Scholar  More

  • in

    Author Correction: Priority list of biodiversity metrics to observe from space

    Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Enschede, the NetherlandsAndrew K. Skidmore, Elnaz Neinavaz, Abebe Ali, Roshanak Darvishzadeh, Marcelle C. Lock & Tiejun WangDepartment of Earth and Environmental Science, Macquarie University, Sydney, New South Wales, AustraliaAndrew K. Skidmore & Marcelle C. LockDepartment of Forest Resources Management, University of British Columbia, Vancouver, British Columbia, CanadaNicholas C. CoopsDepartment of Geography and Environmental Studies, Wollo University, Dessie, EthiopiaAbebe AliRemote Sensing Laboratories, Department of Geography, University of Zurich, Zurich, SwitzerlandMichael E. SchaepmanEuropean Space Research Institute (ESRIN), European Space Agency, Frascati, ItalyMarc PaganiniInstitute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, the NetherlandsW. Daniel KisslingBiodiversity Centre, Finnish Environment Institute (SYKE), Helsinki, FinlandPetteri VihervaaraInstitute of Geographical Sciences, Freie Universität Berlin, Berlin, GermanyHannes FeilhauerRemote Sensing Center for Earth System Research, University of Leipzig, Leipzig, GermanyHannes FeilhauerNatureServe, Arlington, VA, USAMiguel FernandezGeorge Mason University, Fairfax, VA, USAMiguel FernandezGerman Centre for Integrative Biodiversity Research (iDiv), Leipzig, GermanyNéstor FernándezInstitute of Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), GermanyNéstor FernándezGoogle, Zurich, SwitzerlandNoel GorelickTour du Valat, Arles, FranceIlse GeijzendorfferEarth Observation Center (EOC), Remote Sensing Technology Institute, German Aerospace Center (DLR), Oberpfaffenhofen, GermanyUta Heiden & Stefanie HolzwarthDepartment of Visitor Management and National Park Monitoring, Bavarian Forest National Park Administration, Grafenau, GermanyMarco HeurichAlbert Ludwigs University of Freiburg, Freiburg, GermanyMarco HeurichGBIF Secretariat, Copenhagen, DenmarkDonald HobernCollege of Marine Science, University of South Florida, St Petersburg, FL, USAFrank E. Muller-KargerFlemish Institute for Technological Research (VITO), Mol, BelgiumRuben Van De KerchoveComputational Landscape Ecology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, GermanyAngela LauschGeography Department, Humboldt University of Berlin, Berlin, GermanyAngela LauschTechnische Universität Braunschweig, Braunschweig, GermanyPedro J. LeitãoHumboldt-Universität zu Berlin, Berlin, GermanyPedro J. LeitãoWageningen Environmental Research, Wageningen University & Research, Wageningen, the NetherlandsCaspar A. MücherUN Environment World Conservation Monitoring Centre, Cambridge, UKBrian O’ConnorDepartment of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, ItalyDuccio RocchiniDepartment of Applied Geoinformatics and Spatial Planning, Faculty of Environmental Sciences, Czech University of Life Sciences, Prague, Czech RepublicDuccio RocchiniEarth Science Division, NASA, Washington DC, USAWoody TurnerUnilever Europe B.V., Rotterdam, the NetherlandsJan Kees VisInstitute of Geography and Geology, University of Wuerzburg, Würzburg, GermanyMartin WegmannLand Systems and Sustainable Land Management, Geographisches Institut, Universität Bern, Bern, SwitzerlandVladimir Wingate More

  • in

    Effects of long-term integrated agri-aquaculture on the soil fungal community structure and function in vegetable fields

    Effects of the two planting systems on soil fungal diversityIn this study, 561,254 sequences were generated from 15 samples obtained from 5 treatments. Base sequences with a length of 201–300 bp accounted for 97.82% of all sequences (Table S1a,b). Rarefaction curves at a similarity level of 97% indicated that the number of sequences extracted from most samples tended to plateau above 10,000. The number of sequences extracted in the test exceeded 30,000, suggesting that the sequencing data were close to saturation, sequencing depth was reasonable, and the results reflected true sample conditions (Fig. 1). The coverage of all samples was above 99.84%. The range of reads in each sample was between 34,390 and 43,510. The range of Operational Taxonomic Units (OTUs) in each sample was between 145 and 318 (Table 1).Figure 1α-Diversity comparison. Rarefaction curves for OTUs were calculated using Mothur (v1.27.0) with reads normalized to more than 30,000 for each sample using a distance of 0.03 OTU.Full size imageTable 1 Comparison of α-diversity indices in TPP and VEE soil samples.Full size tableThe analysis of alpha diversity showed that with increasing planting time, soil fungal OTUs, the Chao index, and the ACE index in TPP-treated plots increased and then decreased with time. In the VEE-IPBP-treated plots, these 3 indexes increased with time and were 56.94%, 33.81%, and 32.50% higher than those in the TPP-treated plots, respectively, after 6 years of implementation (p  More

  • in

    Distinguishing anthropogenic and natural contributions to coproduction of national crop yields globally

    1.Pellegrini, P. & Fernández, R. J. Crop intensification, land use, and on-farm energy-use efficiency during the worldwide spread of the green revolution. Proc. Natl. Acad. Sci. U. S. A. 115(10), 2335–2340 (2018).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    2.Ray, D. K., Ramankutty, N., Mueller, N. D., West, P. C. & Foley, J. A. Recent patterns of crop yield growth and stagnation. Nat. Commun. 3(1), 1293 (2012).ADS 
    PubMed 
    Article 
    CAS 
    PubMed Central 

    Google Scholar 
    3.Palomo, I., Felipe-Lucia, M. R., Bennett, E. M., Martín-López, B. & Pascual, U. Chapter six—disentangling the pathways and effects of ecosystem service co-production. In Advance Ecology Research (eds Woodward, G. & Bohan, D. A.) 245–283 (Academic Press, 2016).
    Google Scholar 
    4.Lavorel, S., Locatelli, B., Colloff, M. J. & Bruley, E. Co-producing ecosystem services for adapting to climate change. Philos. T. Roy. Soc. B. 375(1794), 20190119 (2020).Article 

    Google Scholar 
    5.Boerema, A., Rebelo, A. J., Bodi, M. B., Esler, K. J. & Meire, P. Are ecosystem services adequately quantified?. J. Appl. Ecol. 54(2), 358–370 (2017).Article 

    Google Scholar 
    6.Maes, J. et al. An indicator framework for assessing ecosystem services in support of the EU Biodiversity Strategy to 2020. Ecosyst. Serv. 17, 14–23 (2016).Article 

    Google Scholar 
    7.Jones, L. et al. Stocks and flows of natural and human-derived capital in ecosystem services. Land Use Policy 52, 151–162 (2016).Article 

    Google Scholar 
    8.Barot, S., Yé, L., Abbadie, L., Blouin, M. & Frascaria-Lacoste, N. Ecosystem services must tackle anthropized ecosystems and ecological engineering. Ecol. Eng. 99, 486–495 (2017).Article 

    Google Scholar 
    9.Remme, R. P., Edens, B., Schröter, M. & Hein, L. Monetary accounting of ecosystem services: a test case for Limburg province, the Netherlands. Ecol. Econ. 112, 116–128 (2015).Article 

    Google Scholar 
    10.Gaiser, T. & Stahr, K. Soil organic carbon, soil formation and soil fertility. In Ecosystem Services and Carbon Sequestration in the Biosphere (eds Lal, R. et al.) 407–418 (Springer, 2013).
    Google Scholar 
    11.FAO and ITPS. Status of the World’s Soil Resources (SWSR)—Main Report (Food and Agriculture Organization of the United Nations and Intergovernmental Technical Panel on Soils, 2015).
    Google Scholar 
    12.Dainese, M. et al. A global synthesis reveals biodiversity-mediated benefits for crop production. Sci. Adv. 5(10), eaax0121 (2019).ADS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    13.Bommarco, R., Kleijn, D. & Potts, S. G. Ecological intensification: harnessing ecosystem services for food security. Trends Ecol. Evol. 28(4), 230–238 (2013).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    14.Zabel, F., Putzenlechner, B. & Mauser, W. Global agricultural land resources—a high resolution suitability evaluation and its perspectives until 2100 under climate change conditions. PLoS ONE 9(9), e107522 (2014).ADS 
    PubMed 
    PubMed Central 
    Article 
    CAS 

    Google Scholar 
    15.Pelletier, N. et al. Energy intensity of agriculture and food systems. Annu. Rev. Environ. Resour. 36(1), 223–246 (2011).Article 

    Google Scholar 
    16.Díaz, S. et al. The IPBES conceptual framework—connecting nature and people. Curr. Opin. Environ. Sustain. 14, 1–16 (2015).Article 

    Google Scholar 
    17.Bennett, E. M. Research frontiers in ecosystem service science. Ecosystems 20(1), 31–37 (2017).Article 

    Google Scholar 
    18.Woods, J., Williams, A., Hughes, J. K., Black, M. & Murphy, R. Energy and the food system. Philos. T. Roy. Soc. B. 365(1554), 2991–3006 (2010).Article 

    Google Scholar 
    19.Foley, J. A. et al. Global consequences of land use. Science 309(5734), 570–574 (2005).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    20.Seppelt, R., Manceur, A. M., Liu, J., Fenichel, E. P. & Klotz, S. Synchronized peak-rate years of global resources use. Ecol. Soc. 19(4), 50 (2014).Article 

    Google Scholar 
    21.Meyfroidt, P. et al. Middle-range theories of land system change. Glob. Environ. Chang. 53, 52–67 (2018).Article 

    Google Scholar 
    22.Fitter, A. H. Are ecosystem services replaceable by technology?. Environ. Res. Econ. 55(4), 513–524 (2013).Article 

    Google Scholar 
    23.Cohen, F., Hepburn, C. J. & Teytelboym, A. Is natural capital really substitutable?. Annu. Rev. Environ. Resour. 44(1), 425–448 (2019).Article 

    Google Scholar 
    24.Ekins, P., Simon, S., Deutsch, L., Folke, C. & De Groot, R. A framework for the practical application of the concepts of critical natural capital and strong sustainability. Ecol. Econ. 44(2–3), 165–185 (2003).Article 

    Google Scholar 
    25.Lassaletta, L., Billen, G., Grizzetti, B., Anglade, J. & Garnier, J. 50 year trends in nitrogen use efficiency of world cropping systems: the relationship between yield and nitrogen input to cropland. Environ. Res. Lett. 9(10), 105011 (2014).ADS 
    Article 

    Google Scholar 
    26.Levers, C., Butsic, V., Verburg, P. H., Müller, D. & Kuemmerle, T. Drivers of changes in agricultural intensity in Europe. Land Use Policy 58, 380–393 (2016).Article 

    Google Scholar 
    27.Coomes, O. T., Barham, B. L., MacDonald, G. K., Ramankutty, N. & Chavas, J.-P. Leveraging total factor productivity growth for sustainable and resilient farming. Nat. Sustain. 2(1), 22–28 (2019).Article 

    Google Scholar 
    28.Fuglie, K. R&D capital, RD spillovers, and productivity growth in world agriculture. Appl. Econ. Perspect. Policy 40(3), 421–444 (2018).Article 

    Google Scholar 
    29.Mueller, N. D. et al. Closing yield gaps through nutrient and water management. Nature 490, 254 (2012).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    30.German, R. N., Thompson, C. E. & Benton, T. G. Relationships among multiple aspects of agriculture’s environmental impact and productivity: a meta-analysis to guide sustainable agriculture. Biol. Rev. 92(2), 716–738 (2017).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    31.Lee, H. & Lautenbach, S. A quantitative review of relationships between ecosystem services. Ecol. Indic. 66, 340–351 (2016).Article 

    Google Scholar 
    32.Lobell, D. B., Schlenker, W. & Costa-Roberts, J. Climate trends and global crop production since 1980. Science 333(6042), 616–620 (2011).ADS 
    CAS 
    Article 

    Google Scholar 
    33.Erb, K.-H. et al. A conceptual framework for analysing and measuring land-use intensity. Curr. Opin. Environ. Sustain. 5(5), 464–470 (2013).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    34.Loos, J. et al. Putting meaning back into “sustainable intensification”. Front. Ecol. Environ. 12(6), 356–361 (2014).Article 

    Google Scholar 
    35.Kleijn, D. et al. Ecological intensification: bridging the gap between science and practice. Trends Ecol. Evol. 34(2), 154–166 (2019).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    36.Stirzaker, R., Biggs, H., Roux, D. & Cilliers, P. Requisite simplicities to help negotiate complex problems. Ambio 39(8), 600–607 (2010).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    37.Kuemmerle, T. et al. Challenges and opportunities in mapping land use intensity globally. Curr. Opin. Environ. Sustain. 5(5), 484–493 (2013).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    38.Garibaldi, L. A., Aizen, M. A., Klein, A. M., Cunningham, S. A. & Harder, L. D. Global growth and stability of agricultural yield decrease with pollinator dependence. Proc. Natl. Acad. Sci. U. S. A. 108(14), 5909–5914 (2011).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    39.Bengtsson, J. Biological control as an ecosystem service: partitioning contributions of nature and human inputs to yield. Ecol. Entomol. 40(S1), 45–55 (2015).Article 

    Google Scholar 
    40.Seppelt, R., Arndt, C., Beckmann, M., Martin, E. A. & Hertel, T. Deciphering the biodiversity-production mutualism in the global food security debate. Trends Ecol. Evol. https://doi.org/10.1016/j.tree.2020.06.012 (2020).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    41.Poore, J. & Nemecek, T. Reducing food’s environmental impacts through producers and consumers. Science 360(6392), 987–992 (2018).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    42.Beckmann, M. et al. Conventional land-use intensification reduces species richness and increases production: a global meta-analysis. Glob. Chang. Biol. 25(6), 1941–1956 (2019).ADS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    43.Garibaldi, L. A. et al. Farming approaches for greater biodiversity, livelihoods, and food security. Trends Ecol. Evol. 32(1), 68–80 (2017).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    44.Monfreda, C., Ramankutty, N. & Foley, J. A. Farming the planet: 2. Geographic distribution of crop areas, yields, physiological types, and net primary production in the year 2000. Glob. Biogeochem. Cycles 22(1), 1–19 (2008).Article 
    CAS 

    Google Scholar 
    45.IFA, IFDC, IPI, PPI, FAO. Fertilizer Use by Crop (FAO, 2002).
    Google Scholar 
    46.IFA. Assessment of Fertilizer Use by Crop at the Global Level 2006/07–2007/08 (IFA, 2009).
    Google Scholar 
    47.IFA. Assessment of Fertilizer Use by Crop at the Global Level 2010–2010/11 (IFA, 2013).
    Google Scholar 
    48.IFA and IPNI. Assessment of Fertilizer Use by Crop at the Global Level (IFA and IPNI, 2017).
    Google Scholar 
    49.FAO. Crops. http://www.fao.org/faostat/en/#data/QC (2018).50.FAO. Capital Stock. http://www.fao.org/faostat/en/#data/CS (2018).51.U.S. Bureau of Labor Statistics. CPI Inflation Calculator. https://data.bls.gov/cgi-bin/cpicalc.pl?cost1=1.00&year1=200001&year2=201401 (2020).52.FAO. Livestock Manure. http://www.fao.org/faostat/en/#data/EMN (2018).53.FAO. Food Balance Sheets: A Handbook 95 (FAO, 2001).
    Google Scholar 
    54.World Bank. The World by Income and Region. https://datatopics.worldbank.org/world-development-indicators/the-world-by-income-and-region.html (2019).55.R Core Team. R: A Language and Environment for Statistical Computing (R Foundation for Statistical Computing, 2019).
    Google Scholar 
    56.RStudio Team. RStudio: Integrated Development for R (RStudio, Inc., 2018).
    Google Scholar 
    57.Cook, R. D. Detection of influential observation in linear regression. Technometrics 19(1), 15–18 (1977).MathSciNet 
    MATH 

    Google Scholar 
    58.Natural Earth. Admin 0—Countries. Version 4.0.0 (accessed 22 October 2017); https://www.naturalearthdata.com/ (2017). More

  • in

    Understanding anatomical plasticity of Argan wood features at local geographical scale in ecological and archaeobotanical perspectives

    Sampling, preparation and treatment of modern reference materialA total of 53 modern wood samples were analyzed. The modern reference samples were collected in 2014 during the annual archaeological field mission, from 36 individuals (Table S1). For some trees, two wood samples of different diameters were collected in order to take into account anatomical variability within individual.The collected individuals showed different conditions of growth described in the introduction section and detailed in the Table 1. With the agreement of the Tifigit inhabitants and local authorities, wood sampling was achieved but samples were not collected from trunks, to avoid injuring trees of major symbolic, ecological and economic importance. Only section samples with perfect axial symmetry were retained to avoid any impact of biomechanical constraints (formation of reaction wood) on wood characters.Once collected, the samples were air-dried during a month at the laboratory. The samples were separately wrapped in tin foil and buried in the sand and then charred without oxygen, at 450 °C for 15 to 20 min depending on the size of the sample. As a result, samples were enriched in carbon (content  > 90%)20,26, reached their maximal shrinkage27, and thus are considered to become morphologically comparable to charcoal produced in medieval fires27,28,29,30,31. The minimum and the maximum diameter of wood samples were measured (mm) using a digital measuring calliper before and after carbonization. The diameter used in the following analyses is the mean of the two measurements carried out before carbonization.Archaeological materialTwenty archaeological charcoal fragments of Argan tree identified during a previous analysis session13 were included in this study (Table S2). All the Argan charcoal fragments were collected in the medieval archaeological deposits of Îgîlîz13. They come from various contexts, for the most part from living units, and belong to the period of highest human activity at the site, between the late 11th and early thirteenth centuries.Quantitative eco-anatomical analysis of wood applied to the Argan treeThe approach consists in measuring constitutive elements of wood and aims to understand variations according to intrinsic (inferred by the branch diameter mainly age of tree18, linked to the existence of growth rings that are often difficult to distinguish) and environmental parameters affecting the cambial activity and thus, rate of growth and wood development20,28,29,30. This high resolution analysis of wood structure, particularly of conductive elements, allows addressing numerous questions that have been successfully solved in the case of the olive tree and the grapevine, such as phenology, ecology, climate, impact of human activities and agricultural practices20,24,25,31,32,33.Argania spinosa wood is diffuse-porous with a dendritic and diagonal arrangement of vessel elements in transversal section34. The axial parenchyma bands are in tangential alignment and composed of multicellular strands. In radial alignment, woody rays are 1–3 cells wide and of heterocellular composition (Fig. 6).Figure 6Wood anatomical features of the Argan tree (in blue) and measured anatomical characters (in red).Full size imageTo apply a quantitative eco-anatomy approach to the Argan tree, both modern charred samples and archaeological charcoal are broken manually in transverse anatomical section. The following wood constitutive elements and anatomical characters related to sap conduction and reserve storage are observed and measured under a reflected-light microscope connected with an image analysis system (DFC300 FX Leica camera and LAS Leica software) (Fig. 6): (1) vessel density (DVS—number of vessels / mm2), (2) vessel surface area (SVS, µm2), (3) ray density (DRA—number of rays / mm2), (4) axial parenchyma density (DPA, number of bands / mm2), (5) Density of wood fenestrated zones bordered on one side by the radial alignment of axial parenchyma cells and on the other side, tangentially, by rays (DWF—number of fenestrated zones / mm2).These anatomical features were measured several times (see ‘Statistical analyses’ section) following radial lines from the cambium inwards the sample and crossing a small number of growth rings (i.e. functional rings from a sap conduction point of view). Moreover, the hydraulic conductivity or vascular conductivity (CD) was assessed using the following formula: CD = (SVS/π)2/DVS (after32,35,36,37). Finally, the ratio ‘Conductive surface / total wood area’ (SC) was calculated.Statistical analysesIn order to determine the number of measurements required for an optimal assessment of anatomical features, a rarefaction method was carried out from the analysis of test wood samples. For each one, repeated measurements of anatomical characters (Surface vessel area (SVS), Density of vessels (DVS), Ray density (DRA), Axial parenchyma density (DPA) and Density of wood fenestrated zones (DWF)) were performed following the aforementioned method and the cumulative mean value was then calculated for each character20,29. For each test sample and anatomical character, the number of measurements of a character required for an optimal assessment was quantified as the minimum number of measurements required to stabilize the mean value (rarefaction curve or cumulative mean curve).Furthermore, different measurement sessions were carried out with the aim of testing possible errors and reproducibility of measurements taken by one or various observers, respectively. The data sets produced were tested using the PCA performed to evaluate the Argan anatomical variability. The ARG8-2 sample was used as test sample. In addition to the initial measurements. The ARG8-2 sample was analyzed 4 times: twice by one operator (ARG8-2 (1-OP1) and ARG8-2 (2-OP1)) and twice by another (ARG8-2 (3-OP2) and ARG8-2 (3-OP2)) at different times. The additional data were incorporated into the PCA as additional individuals for comparison with initial anatomical features of ARG8-2.After showing that measurement errors have no impact on the validity of results and the measurements are reproducible, quantitative eco-anatomical data were processed using a principal component analysis (PCA) in order to evaluate anatomical plasticity in the reference modern material, to appreciate relationships between characters and wood sample caliber and to confront archaeological data to the reference model. PCA was applied on 53 reference modern samples and 7 quantitative variables (anatomical characters) to: (1) validate the hypothesis that there is a significant relationship between the size of the branch and anatomy, as previously demonstrated by analyses of wood development and structure18,20,38 and dendrochronology39; (2) identify the anatomical characters most affected by the age of the branch and, in that case, model the ‘anatomical characters—caliber of the branch’ relationship; (3) develop predictive model that might estimate the minimum branch caliber from eco-anatomical data of archaeological charcoal.Finally, data from analysis of the 20 archaeological charcoal fragments were included in PCA as additional statistical samples. They do not contribute to the development of the reference model, but are compared to the modern reference samples in order to infer the ecological conditions under which Argan trees grew during the Middle Ages. More

  • in

    Changes in taxonomic and functional diversity of plants in a chronosequence of Eucalyptus grandis plantations

    1.Sala, O. E. et al. Global biodiversity scenarios for the year 2100. Science (80- ) 287, 1770–1774 (2000).CAS 
    Article 

    Google Scholar 
    2.Wall, D. H. & Nielsen, U. N. Biodiversity and ecosystem services: is it the same below ground?. Nat. Educ. Knowl. 12, 3–8 (2012).
    Google Scholar 
    3.FAO. Global Forest Resources Assessment 2015: Desk Reference. http://www.fao.org/3/a-i4808e.pdf (2015).4.Filloy, J., Zurita, G. A., Corbelli, J. M. & Bellocq, M. I. On the similarity among bird communities: testing the influence of distance and land use. Acta Oecol. 36, 333–338 (2010).ADS 
    Article 

    Google Scholar 
    5.Santoandré, S., Filloy, J., Zurita, G. A. & Bellocq, M. I. Ant taxonomic and functional diversity show differential response to plantation age in two contrasting biomes. For. Ecol. Manag. 437, 304–313 (2019).Article 

    Google Scholar 
    6.Calviño-Cancela, M. Effectiveness of eucalypt plantations as a surrogate habitat for birds. For. Ecol. Manag. 310, 692–699 (2013).Article 

    Google Scholar 
    7.Santoandré, S., Filloy, J., Zurita, G. A. & Bellocq, M. I. Taxonomic and functional β-diversity of ants along tree plantation chronosequences differ between contrasting biomes. Basic Appl. Ecol. 41, 1–12 (2019).Article 

    Google Scholar 
    8.Corbelli, J. M. et al. Integrating taxonomic, functional and phylogenetic beta diversities: interactive effects with the biome and land use across taxa. PLoS ONE 10, 1–17 (2015).Article 
    CAS 

    Google Scholar 
    9.Phifer, C. C., Knowlton, J. L., Webster, C. R., Flaspohler, D. J. & Licata, J. A. Bird community responses to afforested eucalyptus plantations in the Argentine pampas. Biodivers. Conserv. https://doi.org/10.1007/s10531-016-1126-6 (2016).Article 

    Google Scholar 
    10.Tererai, F., Gaertner, M., Jacobs, S. M. & Richardson, D. M. Eucalyptus invasions in riparian forests: effects on native vegetation community diversity, stand structure and composition. For. Ecol. Manag. 297, 84–93 (2013).Article 

    Google Scholar 
    11.Brancalion, P. H. S. et al. Intensive silviculture enhances biomass accumulation and tree diversity recovery in tropical forest restoration. Ecol. Appl. 29, 1–12 (2019).Article 

    Google Scholar 
    12.Zhang, C., Liu, G., Xue, S. & Wang, G. Soil bacterial community dynamics reflect changes in plant community and soil properties during the secondary succession of abandoned farmland in the Loess Plateau. Soil Biol. Biochem. 97, 40–49 (2016).CAS 
    Article 

    Google Scholar 
    13.Zhu, Y., Wang, Y. & Chen, L. Effects of non-native tree plantations on the diversity of understory plants and soil macroinvertebrates in the Loess Plateau of China. Plant Soil 446, 357–368 (2019).Article 
    CAS 

    Google Scholar 
    14.Zhang, W. et al. Plant functional composition and species diversity affect soil C, N, and P during secondary succession of abandoned farmland on the Loess Plateau. Ecol. Eng. 122, 91–99 (2018).Article 

    Google Scholar 
    15.Munévar, A., Rubio, G. D. & Andrés, G. Changes in spider diversity through the growth cycle of pine plantations in the semi-deciduous Atlantic forest: the role of prey availability and abiotic conditions. For. Ecol. Manag. 424, 536–544 (2018).Article 

    Google Scholar 
    16.Vega, E., Baldi, G., Jobbágy, E. G. & Paruelo, J. Land use change patterns in the Río de la Plata grasslands: the influence of phytogeographic and political boundaries. Agric. Ecosyst. Environ. 134, 287–292 (2009).Article 

    Google Scholar 
    17.Ntshuxeko, V. E. & Ruwanza, S. Physical properties of soil in Pine elliottii and Eucalyptus cloeziana plantations in the Vhembe biosphere, Limpopo Province of South Africa. J. For. Res. https://doi.org/10.1007/s11676-018-0830-3 (2018).Article 

    Google Scholar 
    18.Kerr, T. F. & Ruwanza, S. Does Eucalyptus grandis invasion and removal affect soils and vegetation in the Eastern Cape Province, South Africa?. Austral. Ecol. 41, 328–338 (2016).Article 

    Google Scholar 
    19.Zhang, D. J., Zhang, J., Yang, W. Q. & Wu, F. Z. Potential allelopathic effect of Eucalyptus grandis across a range of plantation ages. Ecol. Res. 25, 13–23 (2010).Article 

    Google Scholar 
    20.Díaz, S. & Cabido, M. Vive la difference: plant functional diversity matters to ecosystem processes: plant functional diversity matters to ecosystem processes. Trends Ecol. Evol. 16, 646–655 (2001).Article 

    Google Scholar 
    21.Petchey, O. L. & Gaston, K. J. Functional diversity: back to basics and looking forward. Ecol. Lett. 9, 741–758 (2006).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    22.Luck, G. W., Lavorel, S., Mcintyre, S. & Lumb, K. Improving the application of vertebrate trait-based frameworks to the study of ecosystem services. J. Anim. Ecol. 81, 1065–1076 (2012).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    23.Lindenmayer, D. et al. Richness is not all: how changes in avian functional diversity reflect major landscape modification caused by pine plantations. Divers. Distrib. 21, 836–847 (2015).Article 

    Google Scholar 
    24.Whittaker, R. H. Vegetation of the Siskiyou Mountains, Oregon and California. Ecol. Monogr. 30, 280–338 (1960).Article 

    Google Scholar 
    25.Swenson, N. G. Functional and Phylogenetic Ecology in R. Use R! (2014). https://doi.org/10.1007/978-1-4614-9542-0.26.Vaccaro, A. S., Filloy, J. & Bellocq, M. I. What land use better preserves taxonomic and functional diversity of birds in a grassland biome?. Avian Conserv. Ecol. 14, 1 (2019).Article 

    Google Scholar 
    27.Blair, J., Nippert, J. & Briggs, J. Grassland Ecology. Ecology and the Environment vol. 8 (Springer, 2014).28.Nic Lughadha, E. et al. Measuring the fate of plant diversity: towards a foundation for future monitoring and opportunities for urgent action. Philos. Trans. R. Soc. B Biol. Sci. 360, 359–372 (2005).CAS 
    Article 

    Google Scholar 
    29.Marteinsdóttir, B. & Eriksson, O. Trait-based filtering from the regional species pool into local grassland communities. J. Plant Ecol. 7, 347–355 (2014).Article 

    Google Scholar 
    30.Salgado Negret, B. La Ecología Funcional como aproximación al estudio, manejo y conservación de la biodiversidad: protocolos y aplicaciones. La ecología funcional como aproximación al estudio, manejo y conservación de la biodiversidad: protocolos y aplicaciones (2015).31.Barbier, S., Gosselin, F. & Balandier, P. Influence of tree species on understory vegetation diversity and mechanisms involved—a critical review for temperate and boreal forests. For. Ecol. Manag. 254, 1–15 (2008).Article 

    Google Scholar 
    32.Zhang, D., Zhang, J., Yang, W., Wu, F. & Huang, Y. Plant and soil seed bank diversity across a range of ages of Eucalyptus grandis plantations afforested on arable lands. Plant Soil 376, 307–325 (2014).CAS 
    Article 

    Google Scholar 
    33.Zhang, C. & Fu, S. Allelopathic effects of eucalyptus and the establishment of mixed stands of eucalyptus and native species. For. Ecol. Manag. 258, 1391–1396 (2009).Article 

    Google Scholar 
    34.Florentine, S. K. & Fox, J. E. D. Allelopathic effects of Eucalyptus victrix L. on Eucalyptus species and grasses. Allelopath. J. 11, 77–83 (2003).
    Google Scholar 
    35.Jobbágy, E. et al. Forestación en pastizales: hacia una visión integral de sus oportunidades y costos ecológicos. Agrociencia X, 109–124 (2006).36.Ruwanza, S., Gaertner, M., Esler, K. J. & Richardson, D. M. Allelopathic effects of invasive Eucalyptus camaldulensis on germination and early growth of four native species in the Western Cape South Africa. South. For. 77, 91–105 (2015).Article 

    Google Scholar 
    37.Suggitt, A. J. et al. Habitat microclimates drive fi ne-scale variation in extreme temperatures. Oikos https://doi.org/10.1111/j.1600-0706.2010.18270.x (2011).Article 

    Google Scholar 
    38.Zellweger, F., Roth, T., Bugmann, H. & Bollmann, K. Beta diversity of plants, birds and butterflies is closely associated with climate and habitat structure. Glob. Ecol. Biogeogr. 26, 898–906 (2017).Article 

    Google Scholar 
    39.Silveira, L. & Alonso, J. Runoff modifications due to the conversion of natural grasslands to forests in a large basin in Uruguay. Hidrol. Process. 329, 320–329 (2009).ADS 
    Article 

    Google Scholar 
    40.Mendoza, C. A., Gallardo, J. F., Turrión, M. B., Pando, V. & Aceñolaza, P. G. Dry weight loss in leaves of dominant species in a successional sequence of the Mesopotamian Espinal (Argentina). For. Syst. 26, 1–10 (2017).
    Google Scholar 
    41.Rodriguez, E. E., Aceñolaza, P. G., Perea, E. L. & Galán de Mera, A. A phytosociological analysis of Butia yatay (Arecaceae) palm groves and gallery forests in Entre Rios, Argentina. Aust. J. Bot. https://doi.org/10.1071/BT16140 (2017).Article 

    Google Scholar 
    42.Piwczyński, M., Puchałka, R. & Ulrich, W. Influence of tree plantations on the phylogenetic structure of understorey plant communities. For. Ecol. Manag. 376, 231–237 (2016).Article 

    Google Scholar 
    43.Csecserits, A. et al. Tree plantations are hot-spots of plant invasion in a landscape with heterogeneous land-use. Agric. Ecosyst. Environ. 226, 88–98 (2016).Article 

    Google Scholar 
    44.Amazonas, N. T. et al. High diversity mixed plantations of Eucalyptus and native trees: an interface between production and restoration for the tropics. For. Ecol. Manag. 417, 247–256 (2018).Article 

    Google Scholar 
    45.Verstraeten, G. et al. Understorey vegetation shifts following the conversion of temperate deciduous forest to spruce plantation. For. Ecol. Manag. 289, 363–370 (2013).Article 

    Google Scholar 
    46.Grass, I., Brandl, R., Botzat, A., Neuschulz, E. L. & Farwig, N. Contrasting taxonomic and phylogenetic diversity responses to forest modifications: comparisons of taxa and successive plant life stages in south African scarp forest. PLoS ONE 10, 1–20 (2015).Article 
    CAS 

    Google Scholar 
    47.Wu, J. et al. Should exotic Eucalyptus be planted in subtropical China: insights from understory plant diversity in two contrasting Eucalyptus chronosequences. Environ. Manag. 56, 1244–1251 (2015).ADS 
    Article 

    Google Scholar 
    48.Jin, D. et al. High risk of plant invasion in the understory of eucalypt plantations in South China. Sci. Rep. 5, 18492 (2016).ADS 
    Article 
    CAS 

    Google Scholar 
    49.Haughian, S. R. & Frego, K. A. Short-term effects of three commercial thinning treatments on diversity of understory vascular plants in white spruce plantations of northern New Brunswick. For. Ecol. Manag. 370, 45–55 (2016).Article 

    Google Scholar 
    50.Smith, G. F., Iremonger, S., Kelly, D. L., O’Donoghue, S. & Mitchell, F. J. G. Enhancing vegetation diversity in glades, rides and roads in plantation forests. Biol. Conserv. 136, 283–294 (2007).Article 

    Google Scholar 
    51.Aceñolaza, P. G., Rodriguez, E. E. & Diaz, D. Efecto de prácticas de manejo silvícola sobre la diversidad vegetal bajo plantaciones de Eucalyptus grandis. In 4to Congreso Forestal Argentino y Latinoamericano (2013).52.Connell, J. H. & Slatyer, R. O. Mechanisms of succession in natural communities and their role in community stability and organization. Am. Nat. 111, 1119–1144 (1977).Article 

    Google Scholar 
    53.Pedley, S. M. & Dolman, P. M. Multi-taxa trait and functional responses to physical disturbance. J. Anim. Ecol. 83, 1542–1552 (2014).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    54.Birkhofer, K., Smith, H. G., Weisser, W. W., Wolters, V. & Gossner, M. M. Land-use effects on the functional distinctness of arthropod communities. Ecography (Cop.) https://doi.org/10.1111/ecog.01141 (2015).Article 

    Google Scholar 
    55.Mangels, J., Fiedler, K., Schneider, F. D. & Blu, N. Diversity and trait composition of moths respond to land-use intensification in grasslands : generalists replace specialists. Biodivers. Conserv. https://doi.org/10.1007/s10531-017-1411-z (2017).Article 

    Google Scholar 
    56.Morello, J., Matteucci, S. D., Rodriguez, A. F. & Silva, M. Ecorregiones y complejos ecosistemicos argentino. (2012).57.Cabrera, Á. Fitogeografía de la República Argentina. Bol. Soc. Argent. Bot. 14, 1–42 (1971).
    Google Scholar 
    58.Rodriguez, E. E., Aceñolaza, P. G., Picasso, G. & Gago, J. Plantas del bajo Rio Uruguay: árboles, arbustos, herbáceas, lianas y epifitas. (2018).59.Bilenca, D. & Miñarro, F. Identificación de Áreas Valiosas de Pastizal (AVPs) en las Pampas y Campos de Argentina Uruguay y sur de Brasil. Vasa https://doi.org/10.1007/s13398-014-0173-7.2 (2004).Article 

    Google Scholar 
    60.Inta. Plan de Tecnologia Regional 2009–2011. INTA Cent. Reg. Entre Rios (2011).61.Aguerre, M. et al. Manual para productores de Eucaliptos de la Mesopotamia Argentina. (1995).62.Aparicio, J. L., Larocca, F. & Dalla Tea, F. Silvicultura de establecimiento de Eucalyptus grandis. IDIA XXI, Revista de Información sobre Investigación y Desarrollo Agropecuario 66–69 (2005).63.Vilela, E., Leite, H. G. & Jaffe, K. Level of economic damage for leaf-cutting ants (Hymenoptera: Formicidae) in Eucalyptus plantations in Brazil. Sociobiology 42, 1–10 (2015).
    Google Scholar 
    64.Larroca, F., Dalla Tea, F. & Aparicio, J. L. Técnicas de implantación y manejo de eucaliptus para pequeños y medianos forestadores en Entre Ríos y Corrientes. in XIX Jornadas Forestales de Entre Ríos. (2004).65.Burkart, A. Flora ilustrada de la provincia de Entre Ríos. (INTA, 1969).66.Burkart, A. Flora ilustrada de Entre Ríos (Argentina). Parte 2 Gramíneas. Colección Científica del INTA (1969).67.Peyras, M., Vespa, N. I., Bellocq, M. I. & Zurita, G. A. Quantifying edge effects : the role of habitat contrast and species specialization. J. Insect Conserv. 17, 807–820 (2013).Article 

    Google Scholar 
    68.Werenkraut, V., Fergnani, P. N. & Ruggiero, A. Ants at the edge: a sharp forest-steppe boundary influences the taxonomic and functional organization of ant species assemblages along elevational gradients in northwestern Patagonia (Argentina). Biodivers. Conserv. 24, 287–308 (2015).Article 

    Google Scholar 
    69.Diaz, S., Cabido, M. & Casanoves, F. Plant functional traits and environmental filters at a regional scale. J. Veg. Sci. 9, 113–122 (1998).Article 

    Google Scholar 
    70.Grime, J. P. Benefits of plant diversity to ecosystems: immediate, filter and founder effects. J. Ecol. 86, 902–910 (1998).Article 

    Google Scholar 
    71.Carreño-Rocabado, G. et al. Land-use intensification effects on functional properties in tropical plant communities. Ecol. Appl. https://doi.org/10.1007/s11548-012-0737-y (2015).Article 

    Google Scholar 
    72.Pérez-Harguindeguy, N. et al. New Handbook for standardized measurment of plant functional traits worldwide. Aust. J. Bot. 61, 167–234 (2013).Article 

    Google Scholar 
    73.Laliberté, E. & Legendre, P. A distance-based framework for measuring functional diversity from multiple traits. Ecology 91, 299–305 (2010).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    74.Legendre, P. & Legendre, L. F. J. Numerical Ecology. (Elsevier, 2012).75.Kembel, S. W. et al. Package ‘ picante ’: Integrating Phylogenies and Ecology. Cran-R 1–55 (2018). https://doi.org/10.1093/bioinformatics/btq166 >.License.76.Swenson, N. G., Anglada-Cordero, P. & Barone, J. A. Deterministic tropical tree community turnover: evidence from patterns of functional beta diversity along an elevational gradient. Proc. R. Soc. B Biol. Sci. 278, 877–884 (2011).Article 

    Google Scholar 
    77.Cribari-Neto, F. & Zeileis, A. Journal of Statistical Software. J. Stat. Softw. 34, 1–24 (2010).Article 

    Google Scholar 
    78.Burnham, K. P. & Anderson, D. R. Model Selection and Multimodel Inference: A Practical Information-Theoretic Approach (Springer, 2002).MATH 

    Google Scholar 
    79.Zuur, A. F., Ieno, E. N. & Elphick, C. S. A protocol for data exploration to avoid common statistical problems. Methods Ecol. Evol. 1, 3–14 (2010).Article 

    Google Scholar 
    80.Grace, J. B. Structural Equation Modeling and Natural Systems. (Cambridge University Press, 2006).81.Fan, Y. et al. Applications of structural equation modeling (SEM) in ecological studies: an updated review. Ecol. Process. 5, 19 (2016).ADS 
    Article 

    Google Scholar 
    82.Lefcheck, J. S. piecewiseSEM: piecewise structural equation modelling in r for ecology, evolution, and systematics. Methods Ecol. Evol. 7, 573–579 (2016).Article 

    Google Scholar 
    83.Lefcheck, J., Byrnes, J. & Grace, J. Package ‘ piecewiseSEM ’. R (2019).84.Brown, A. M. et al. The fourth-corner solution – using predictive models to understand how species traits interact with the environment. Methods Ecol. Evol. 5, 344–352 (2014).Article 

    Google Scholar 
    85.Hastie, T., Tibshirani, R. & Friedman, J. The Elements of Statistical Learning: Data Mining, Inference and Prediction. (2009).86.Barton, K. Package ‘MuMIn’.Multi-Model Inference. (2018).87.Dawson, S. K. et al. Plant traits of propagule banks and standing vegetation reveal flooding alleviates impacts of agriculture on wetland restoration. J. Appl. Ecol. 54, 1907–1918 (2017).Article 

    Google Scholar 
    88.QGIS Development Team. QGIS Geographic Information System. Open Source Geospatial Foundation Project. (2019). http://qgis.osgeo.org More

  • in

    Impacts of sheep versus cattle livestock systems on birds of Mediterranean grasslands

    Study area and parcel selectionThe study was conducted in Castro Verde Special Protection Area (SPA), located in southern Portugal (Fig. 1). The climate is Mediterranean, with hot summers (30–35 °C on average in July) and mild winters (averaging 5–8 °C in January), and over 75% of annual rainfall (500–600 mm) concentrated in October–March. The landscape is flat or gently undulating (100–300 m), mainly dominated by open areas used for rainfed pastures (ca. 60%) and annual crops (ca. 25%), and to a less extent by open woodlands (ca. 7%)15.Figure 1(a) Location of the study area within the Castro Verde Special Protected Area (SPA), southern Portugal. (b) Distribution of the 27 sheep (dark grey polygons) and 23 cattle (light grey polygons) grazing parcels and (c) Sampling scheme applied to each parcel surveyed. Bird counts were done at the centroid of the parcel (white dot) whereas vegetation sampling was performed at the indicated 10 points (black dots). The area covered with pastures and annual crops (derived from CORINE land cover 2018—https://land.copernicus.eu/pan-european/corine-land-cover/clc2018) is shown in yellow. The map was done using the version 3.10.0 of QGIS—https://qgis.org/en/site/index.html.Full size imageSince 1995, part of the study area has benefited from a CAP agri-environment aiming to protect the traditional farming system16. This scheme provides financial support to farmers for agricultural practices considered favourable to conservation, including the traditional rotation of cereals and fallows, the maintenance of low stocking rates (usually related with sheep grazing systems), and sowing of crops benefiting grassland birds16. However, in recent years the traditional farming system has been declining, with many farmers converting to specialized livestock systems, mainly, cattle grazing systems, with an increase of stocking rates7,15.Parcel selection started by identifying grasslands grazed by either sheep or cattle, based on parcel-level statistical information from 2010 provided by the Portuguese Ministry of Agriculture7. To minimize potentially confounding effects of adjacent land uses (edge effects) and other non-crop elements within parcels on bird assemblages, we excluded parcels less than 100 m from shrubland or forested areas, with shrub and tree cover  > 5% and with a minimum size of 10 ha. In January 2019 we visited 100 pre-selected parcels which were grazed by either sheep or cattle in 2010 in order to confirm the parcel land use in the agricultural year of 2018/2019, aiming to sample a balanced proportion of 50 sheep and cattle grazed parcels. Additional livestock information for the agricultural year of 2018/2019 was obtained during systematic visits to targeted parcels (see “Grazing Regime” section from Methods). We ended up with 23 cattle parcels and 27 sheep parcels (Fig. 1).Bird and vegetation dataBreeding birds were sampled twice in each parcel during 7–16 April and 1–15 May 2019 respectively, always by the same observer (R.F.R). This was done to take into account species-specific breeding phenology in the area (early and late breeders)17 and minimize bias due to other factors (like weather or disturbance). Sampling was conducted using standardized 10 min point counts18 carried out at the central point of the parcel (Fig. 1). As the open terrain allowed for high visibility, a large detection radius was used, and all birds detected within 100 m of the central point were identified and counted. This radius is roughly similar to the one previously used for characterizing bird populations in the region19. All counts were carried out in the first four hours after sunrise and in the last two hours before sunset, with none in heavy or persistent rain, or in strong wind conditions. To estimate bird species richness and occurrences in each parcel, we pooled the data from the two counts. Species-level analyses focused on the six most common species, which occurred in  > 30% of the parcels (see Supplementary Table S1). In addition to presence/absence, we also estimated population densities, using the count which yielded the highest estimate of density for each species (assuming this is the best indicator of population density, given the potential phenology and detectability biases above mentioned). Bird densities were based on the number of males simultaneously detected and expressed as breeding pairs/10 ha or males/10 ha (in the case of Little Bustard Tetrax tetrax and Common Quail Coturnix coturnix). Categorization to the genus level was made for the Crested and Thekla larks (Galerida cristata and G. theklae) due to difficulties in correctly identifying all individuals of these two very similar species in the field.Vegetation height and cover were measured once in each parcel, between April 22 and May 6. Vegetation height was estimated in a set of ten 3 m radius plots defined inside the 100 m buffer (Fig. 1). In each plot, ten measurements of vegetation height were taken at random locations, for a total of 100 measurements per parcel. Vegetation height was measured using a 50 cm ruler and was defined as the highest point of vegetation projection within 3 cm of the ruler20. All values were estimated to the nearest half centimeter. When no vegetation was present (bare soil, soil litter, rocks or animal dung) the height was set to zero (0) but these measurements were not considered to estimate the mean height of the sward. Vegetation cover was measured inside a 50 × 50 cm quadrat placed at each of the ten grid points, by visual estimation to the nearest 5% of the percentage of the quadrat area covered by vegetation21 (Fig. 1). Vegetation height and cover measurements were averaged within each parcel.Grazing regimeThe number and type of livestock in each parcel as well as the extent of the grazing period since the start of the year (2019) were gathered from interviews (Supplementary Information S1) to land managers during 1–15 May 2019. This information was further validated, and corrected in a few cases, through field checks during regular visits (made at two-week intervals) to the parcels (see “Bird and vegetation data” section from Methods). Three grazing regime indicators were estimated for the whole period (January–May 2019): livestock type (either sheep or cattle), animal density, and grazing pressure. The animal density in each parcel was calculated as the average density (animals per hectare) of any species (regardless of being sheep or cattle) that grazed the parcel during the 5-months period. Stocking Rate translated animal density into livestock unit (LU) per hectare (LU/ha), between January and May, according to the following criteria: one adult bovine = 1 LU; bovine aged  More

  • in

    Hydrologic variation influences stream fish assemblage dynamics through flow regime and drought

    1.Poff, N. L. et al. The natural flow regime. Bioscience 47, 769–784. https://doi.org/10.2307/1313099 (1997).Article 

    Google Scholar 
    2.Naiman, R. J., Latterell, J. J., Pettit, N. E. & Olden, J. D. Flow variability and the biophysical vitality of river systems. CR Geosci. 340, 629–643. https://doi.org/10.1016/j.crte.2008.01.002 (2008).Article 

    Google Scholar 
    3.Larson, E. R., Magoulick, D. D., Turner, C. & Laycock, K. H. Disturbance and species displacement: Different tolerances to stream drying and desiccation in a native and an invasive crayfish. Freshw. Biol. 54, 1899–1908. https://doi.org/10.1111/j.1365-2427.2009.02243.x (2009).Article 

    Google Scholar 
    4.Magoulick, D. D. & Kobza, R. M. The role of refugia for fishes during drought: A review and synthesis. Freshw. Biol. 48, 1186–1198 (2003).Article 

    Google Scholar 
    5.Poff, N. L. & Allan, J. D. Functional organization of stream fish assemblages in relation to hydrological variability. Ecology 76, 606–627 (1995).Article 

    Google Scholar 
    6.Bruckerhoff, L. A., Leasure, D. R. & Magoulick, D. D. Flow-ecology relationships are spatially structured and differ among flow regimes. J. Appl. Ecol. 56, 398–412. https://doi.org/10.1111/1365-2664.13297 (2019).Article 

    Google Scholar 
    7.Poff, N. L. et al. The ecological limits of hydrologic alteration (ELOHA): A new framework for developing regional environmental flow standards. Freshw. Biol. 55, 147–170. https://doi.org/10.1111/j.1365-2427.2009.02204.x (2010).Article 

    Google Scholar 
    8.Warfe, D. M., Hardie, S. A., Uytendaal, A. R., Bobbi, C. J. & Barmuta, L. A. The ecology of rivers with contrasting flow regimes: Identifying indicators for setting environmental flows. Freshw. Biol. 59, 2064–2080. https://doi.org/10.1111/fwb.12407 (2014).Article 

    Google Scholar 
    9.Kennard, M. J. et al. Classification of natural flow regimes in Australia to support environmental flow management. Freshw. Biol. 55, 171–193. https://doi.org/10.1111/j.1365-2427.2009.02307.x (2010).Article 

    Google Scholar 
    10.Belmar, O., Velasco, J. & Martinez-Capel, F. Hydrological classification of natural flow regimes to support environmental flow assessments in intensively regulated Mediterranean Rivers, Segura River Basin (Spain). Environ. Manag. 47, 992–1004. https://doi.org/10.1007/s00267-011-9661-0 (2011).ADS 
    Article 

    Google Scholar 
    11.Mcmanamay, R. A. & Frimpong, E. A. Hydrologic filtering of fish life history strategies across the United States: Implications for stream flow alteration. Ecol. Appl. 25, 243–263. https://doi.org/10.1890/14-0247.1 (2015).Article 
    PubMed 

    Google Scholar 
    12.Winemiller, K. O. & Rose, K. A. Patterns of life-history diversification in North-American Fishes—Implications for population regulation. Can. J. Fish. Aquat. Sci. 49, 2196–2218 (1992).Article 

    Google Scholar 
    13.Olden, J. D. & Kennard, M. J. Intercontinental comparison of fish life history strategies along a gradient of hydrologic variability. Am. Fish. Soc. Symp. 73, 83–107 (2010).
    Google Scholar 
    14.Grossman, G. D., Ratajczak, R. E. Jr., Crawford, M. & Freeman, M. C. Assemblage organization in stream fishes: Effects of environmental variation and interspecific interactions. Ecol. Monogr. 68, 395–420 (1998).Article 

    Google Scholar 
    15.Fitzgerald, D. B., Winemiller, K. O., Perez, M. H. S. & Sousa, L. M. Seasonal changes in the assembly mechanisms structuring tropical fish communities. Ecology 98, 21–31. https://doi.org/10.1002/ecy.1616 (2017).Article 
    PubMed 

    Google Scholar 
    16.Lynch, D. T., Leasure, D. R. & Magoulick, D. D. Flow alteration-ecology relationships in Ozark Highland streams: Consequences for fish, crayfish and macroinvertebrate assemblages. Sci. Total Environ. 672, 680–697. https://doi.org/10.1016/j.scitotenv.2019.03.383 (2019).ADS 
    CAS 
    Article 
    PubMed 

    Google Scholar 
    17.Lynch, D. T., Leasure, D. R. & Magoulick, D. D. The influence of drought on flow-ecology relationships in Ozark Highland streams. Freshw. Biol. 63, 946–968. https://doi.org/10.1111/fwb.13089 (2018).Article 

    Google Scholar 
    18.Matthews, W. J., Marsh-Matthews, E., Cashner, R. C. & Gelwick, F. Disturbance and trajectory of change in a stream fish community over four decades. Oecologia 173, 955–969. https://doi.org/10.1007/s00442-013-2646-3 (2013).ADS 
    Article 
    PubMed 

    Google Scholar 
    19.Taylor, C. M. & Warren, M. L. Dynamics in species composition of stream fish assemblages: Environmental variability and nested subsets. Ecology 82, 2320–2330. https://doi.org/10.1890/0012-9658(2001)082[2320:Discos]2.0.Co;2 (2001).Article 

    Google Scholar 
    20.Matthews, W. J. & Marsh-Matthews, E. Dynamics of an upland stream fish community over 40 years: Trajectories and support for the loose equilibrium concept. Ecology 97, 706–719. https://doi.org/10.1890/14-2179.1 (2016).Article 
    PubMed 

    Google Scholar 
    21.Cook, R., Angermeier, R., Finn, D., Poff, N. & Krueger, K. Geographic variation in patterns of nestedness among local stream fish assemblages in Virginia. Oecologia 140, 639–649 (2004).ADS 
    Article 

    Google Scholar 
    22.Leasure, D. R., Magoulick, D. D. & Longing, S. D. Natural flow regimes of the Ozark-Ouachita interior highlands region. River Res. Appl. 32, 18–35. https://doi.org/10.1002/rra.2838 (2016).Article 

    Google Scholar 
    23.Adamski, J., Petersen, J., Freiwald, D. & Davis, J. Environmental and Hydrologic Setting of the Ozark Plateaus Study Unit, Arkansas, Kansas, Missouri, and Oklahoma 69 (National Water-Quality Assessment Program, 1995).
    Google Scholar 
    24.Fenneman, N. M. Physiography of Eastern United States (McGraw-Hill, 1938).
    Google Scholar 
    25.Hunrichs, R. Identification and classification of perennial streams of Arkansas (U.S. Geological Survey Water Resources Investigations Report 83-4063, 1983).
    Google Scholar 
    26.Hedman, E., Skelton, J. & Freiwald, D. Flow characteristics for selected springs and streams in the Ozark subregion, Arkansas, Kansas, Missouri, and Oklahoma (U.S. Geological Survey Hydrologic Investigations Atlas HA-688, 1987).
    Google Scholar 
    27.Qiao, L., Zou, C. B., Gaitan, C. F., Hong, Y. & McPherson, R. A. Analysis of precipitation projections over the climate gradient of the Arkansas Red River Basin. J. Appl. Meteorol. Clim. 56, 1325–1336. https://doi.org/10.1175/Jamc-D-16-0201.1 (2017).ADS 
    Article 

    Google Scholar 
    28.Kilkenny, C., Browne, W. J., Cuthill, I. C., Emerson, M. & Altman, D. G. Improving bioscience research reporting: The ARRIVE guidelines for reporting animal research. PLoS Biol. 8, e1000412. https://doi.org/10.1371/journal.pbio.1000412 (2010).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    29.Zippin, C. An evaluation of the removal method of estimating animal populations. Biometrics 12, 163–189. https://doi.org/10.2307/3001759 (1956).Article 

    Google Scholar 
    30.Van Deventer, J. S. & Platts, W. S. A Computer Software System for Entering, Managing, and Analyzing Fish Capture Data from Streams (U.S. Dept. of Agriculture, Forest Service, 1985).Book 

    Google Scholar 
    31.ter Braak, C. J. F. & Smilauer, P. CANOCO Reference Manual and User’s Guide to Canoco for Windows: Software for Canonical Community Ordination (Version 4) (Microcomputer power, 2002).32.Lepš, J. & Šmilauer, P. Multivariate Analysis of Ecological Data Using CANOCO (Cambridge University Press, 2003).Book 

    Google Scholar 
    33.Burnham, K. & Anderson, D. Model Selection and Multimodel Inference: A Practical Information-Theoretic Approach 2nd edn. (Springer, 2002).MATH 

    Google Scholar 
    34.R_Core_Team. R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing. http://www.R-project.org/ (Vienna, Austria, 2016).35.Hallett, L. M. et al. CODYN: AnR package of community dynamics metrics. Methods Ecol. Evol. 7, 1146–1151. https://doi.org/10.1111/2041-210x.12569 (2016).Article 

    Google Scholar 
    36.Robison, H. W. & Buchanan, T. M. Fishes of Arkansas (University of Arkansas Press, 1988).
    Google Scholar 
    37.Pflieger, W. L. The Fishes of Missouri (Missouri Department of Conservation, 1975).
    Google Scholar 
    38.Winemiller, K. O. Life-history strategies and the effectiveness of sexual selection. Oikos 63, 318–327. https://doi.org/10.2307/3545395 (1992).Article 

    Google Scholar 
    39.Hoeinghaus, D. J., Winemiller, K. O. & Birnbaum, J. S. Local and regional determinants of stream fish assemblage structure: Inferences based on taxonomic vs. functional groups. J. Biogeogr. 34, 324–338. https://doi.org/10.1111/j.1365-2699.2006.01587.x (2007).Article 

    Google Scholar 
    40.Whiterod, N. S., Hammer, M. P. & Vilizzi, L. Spatial and temporal variability in fish community structure in Mediterranean climate temporary streams. Fundam. Appl. Limnol. 187, 135–150. https://doi.org/10.1127/fal/2015/0771 (2015).Article 

    Google Scholar 
    41.Driver, L. J. & Hoeinghaus, D. J. Spatiotemporal dynamics of intermittent stream fish metacommunities in response to prolonged drought and reconnectivity. Mar. Freshw. Res. 67, 1667–1679. https://doi.org/10.1071/Mf15072 (2016).Article 

    Google Scholar 
    42.Labbe, T. R. & Fausch, K. D. Dynamics of intermittent stream habitat regulate persistence of a threatened fish at multiple scales. Ecol. Appl. 10, 1774–1791 (2000).Article 

    Google Scholar 
    43.Colvin, R., Giannico, G. R., Li, J., Boyer, K. L. & Gerth, W. J. Fish use of intermittent watercourses draining agricultural lands in the upper Willamette River Valley, Oregon. Trans. Am. Fish. Soc. 138, 1302–1313. https://doi.org/10.1577/t08-150.1 (2009).Article 

    Google Scholar 
    44.Kerezsy, A. G., Keith, M., Maria, F., & Skelton, P. in Intermittent Rivers and Ephemeral Streams: Ecology and Management (eds. Thibault, B. D., & Nuria, B. A.) (Academic Press, 2017).45.Franssen, N. R., Tobler, M. & Gido, K. B. Annual variation of community biomass is lower in more diverse stream fish communities. Oikos 120, 582–590. https://doi.org/10.1111/j.1600-0706.2010.18810.x (2011).Article 

    Google Scholar 
    46.Falke, J. A. et al. The role of groundwater pumping and drought in shaping ecological futures for stream fishes in a dryland river basin of the western Great Plains, USA. Ecohydrology 4, 682–697. https://doi.org/10.1002/eco.158 (2011).Article 

    Google Scholar 
    47.Perkin, J. S. et al. Groundwater declines are linked to changes in Great Plains stream fish assemblages. Proc. Natl. Acad. Sci. USA 114, 7373–7378. https://doi.org/10.1073/pnas.1618936114 (2017).CAS 
    Article 
    PubMed 

    Google Scholar 
    48.Lake, P. S. Ecological effects of perturbation by drought in flowing waters. Freshw. Biol. 48, 1161–1172. https://doi.org/10.1046/j.1365-2427.2003.01086.x (2003).Article 

    Google Scholar 
    49.Ludlam, J. P. & Magoulick, D. D. Spatial and temporal variation in the effects of fish and crayfish on benthic communities during stream drying. J. N. Am. Benthol. Soc. 28, 371–382. https://doi.org/10.1899/08-149.1 (2009).Article 

    Google Scholar 
    50.McManamay, R. A., Bevelhimer, M. S. & Frimpong, E. A. Associations among hydrologic classifications and fish traits to support environmental flow standards. Ecohydrology 8, 460–479. https://doi.org/10.1002/eco.1517 (2015).Article 

    Google Scholar 
    51.Hodges, S. W. & Magoulick, D. D. Refuge habitats for fishes during seasonal drying in an intermittent stream: Movement, survival and abundance of three minnow species. Aquat. Sci. 73, 513–522. https://doi.org/10.1007/s00027-011-0206-7 (2011).Article 

    Google Scholar 
    52.Magalhaes, M., Beja, P., Schlosser, I. & Collares-Pereira, M. Effects of multi-year droughts on fish assemblages of seasonally drying Mediterranean streams. Freshw. Biol. 52, 1494–1510 (2007).Article 

    Google Scholar 
    53.Matthews, W. & Marsh-Matthews, E. Effects of drought on fish across axes of space, time and ecological complexity. Freshw. Biol. 48, 1232–1253 (2003).
    Article 

    Google Scholar 
    54.Driver, L. J. & Hoeinghaus, D. J. Fish metacommunity responses to experimental drought are determined by habitat heterogeneity and connectivity. Freshw. Biol. 61, 533–548. https://doi.org/10.1111/fwb.12726 (2016).Article 

    Google Scholar  More