DOI: 10.6084/m9.figshare.30231592.v2
title: Sequential thresholds shape drylands´ multitrophic response to aridification

description: <b>Dataset_Arid_Ecoregions</b><b>Title:</b> <i>Sequential thresholds shape drylands’ multitrophic response to aridification</i>Dataset DescriptionThe <i>Dataset_Arid_Ecoregions</i> contains spatial, multitrophic biodiversity and environmental data for 290 global dryland ecoregions used in the study <i>“Sequential thresholds shape drylands’ multitrophic response to aridification.”</i> It integrates taxonomic and functional group richness, aridity, human influence, productivity, and land use to evaluate biodiversity responses to increasing aridity. The main shapefile (<code>arid_ecoregions_anotated.shp</code>) includes richness metrics for plants (species, genuses, families, classes, phyla), bacteria, fungi, invertebrates, vertebrates, and parasites. Functional group richness (producers, consumers, scavengers, decomposers) and environmental covariates (human disturbance, NDVI productivity, land-use change, temperature anomaly) are provided per ecoregion. Data sources include Maestre et al. (2021) for dryland delimitation and Trabucco & Zomer (2019) for aridity. The RAR archive includes <i>data</i>, <i>scripts</i>, and <i>output</i> folders. Users should unzip it on their Desktop and run scripts 00–04 in R to reproduce all analyses and figures.Data Structure and SourcesEcoregion DelimitationDryland ecoregions follow the <b>global dryland map</b> by <i>Maestre et al. (2021)</i>, based on <i>Dinerstein et al. (2017)</i>. The shapefile includes polygon boundaries, coordinates, and biogeographical metadata.AridityMean aridity values (1 – Mean Aridity Index) are derived from <i>Trabucco and Zomer (2019)</i>.BiodiversityTaxonomic richness is provided across multiple trophic levels and biological groups:<b>Microorganisms:</b> bacteria (bact_vl), fungi (fung_vl), parasites (para_vl)<b>Plants (Producers):</b> represented by richness at species (<b>species</b>), genus (<b>genuses</b>), family (<b>familis</b>), class (<b>classes</b>), and phylum (<b>phyla</b>) levels<b>Invertebrates:</b> earthworms (worm_vl), ants (ant_val), termites (ter_val), bees (bee_val), dragonflies (odnt_vl)<b>Vertebrates:</b> fish (fish_vl), amphibians (amph_vl), mammals (mamm_vl), birds (bird_vl), reptiles (rep_vl1)Functional and Trophic GroupsTaxa are grouped into:<b>Producers:</b> plants (<i>species</i>)<b>Primary consumers</b> (pc_val, composite)<b>Secondary consumers</b> (sc_val, composite including amphibians and fish)<b>Tertiary consumers</b> (tc_val)<b>Scavengers</b> (scav_vl)<b>Decomposers</b> (composite of bact_vl + fung_vl)See Supplementary Information for detailed grouping criteria.Anthropogenic and Environmental Covariates<b>Human disturbance index:</b> integrates accessibility, roads, light pollution, livestock density, population, and urban footprint<b>Temperature anomaly:</b> climate trends during 1980–2022<b>Land-use change:</b> frequency of cropland and pasture (1960–2019)<b>Productivity:</b> mean NDVI (1999–2019)Shapefile AttributesMain shapefile: <b>arid_ecoregions_anotated.shp</b>Contains 35 fields including:Unique ecoregion ID (ecoregn)Biome and realm namesPlant richness at multiple taxonomic levels: species (<b>species</b>), genuses (<b>genuses</b>), families (<b>familis</b>), classes (<b>classes</b>), phyla (<b>phyla</b>)Richness of invertebrates and vertebrates (ant_val, worm_vl, ter_val, bee_val, odnt_vl, fish_vl, amph_vl, mamm_vl, bird_vl, rep_vl1)Functional consumer richness (pc_val, sc_val, tc_val)Scavenger (scav_vl), parasite (para_vl), bacteria (bact_vl), fungi (fung_vl) richnessHuman disturbance (hum_val), climate anomaly (cli_val), NDVI productivity (ndvi)Land-use frequencies (lu_crop, lu_past, lu_for, l_crp_g)<b>Spatial geometry:</b> multipolygons with CRS WGS 84 (EPSG:4326)Spatial Extentxmin: -180xmax: 180ymin: -54.08059ymax: 72.91535<br>Total polygons: <b>290 dryland ecoregions</b>File FormatsAnnotated ESRI shapefile (.shp) with biodiversity and environmental fieldsR scripts for data processing, modeling, and visualizationFolder StructureThe RAR archive contains three folders:<b>data/</b> — all spatial files including <code>arid_ecoregions_anotated.shp</code><b>scripts/</b> — all R scripts to reproduce analyses and figures<b>output/</b> — stores analysis results (figures, tables, CSVs)Scripts Overview<code>00_load_packages_and_setup.R</code> — package loading and setup<code>01_data_import_and_cleaning.R</code> — data import and cleaning<code>02_threshold_analysis.R</code> — model fitting and changepoint analysis<code>03_biodiversity_loss_mapping.R</code> — biodiversity loss mapping<code>04_multitrophic_loss_models.R</code> — multitrophic dependency modellingHow to Use<b>Unzip</b> the file <code>Dataset_Arid_Ecoregions.rar</code> into a folder on your <b>Desktop</b> (e.g., <code>~/Desktop/Dataset_Arid_Ecoregions/</code>).In R, with the <code>here</code> package installed, run the scripts sequentially (00 to 04). The scripts use relative paths via "here()" so no manual directory changes are needed.Scripts automatically load the data, process analyses, and reproduce all manuscript figures:Scripts 02–04 generate Figures 2–4.Figure 1 uses external data from Maestre et al. (2021): https://datadryad.org/stash/dataset/doi:10.5061/dryad.dfn2z351sOutputs are saved in the <code>output/</code> folder.SubjectsBiological Sciences - Ecology - Ecosystems - BiodiversityFundingGeneralitat Valenciana and European Fund (CIAPOS/199/2022)Generalitat Valenciana (CIACIF/2023/176)Ministerio de Ciencia, Innovación y Universidades – Biodiversa+ Project Integradiv (PCI2022-135020-2)ContactFor questions about data and/or analyses, contact:<br><b>Jon Morant Etxebarria</b><br>jmorantetxebarria@gmail.com<br><br>