DOI: 10.5061/dryad.ksn02v7hk
title: Data from: Assessing contributions of deterministic vs. stochastic processes to local species assembly: A field experiment with annual plant-dominated communities in gypsum systems

description: Here, we provide a dataset from a field experiment designed and performed
 to assess the contributions of both functional filtering and stochastic
 (i.e., lack of trait selection) events to assembly processes at a fine
 spatial scale in a dryland gypsum annual plant-dominated community by
 evaluating the effects of seed availability (natural soil seed banks vs.
 seed-free soil) and main biotic filters (biocrusts vs. perennial tussocks)
 on realised local assemblages.
description: # Data from: Assessing contributions of deterministic vs. stochastic
 processes to local species assembly: A field experiment with annual
 plant-dominated communities in gypsum systems Dataset DOI:
 [10.5061/dryad.ksn02v7hk](10.5061/dryad.ksn02v7hk) ## Description of the
 data and file structure The database shows cover values (in percentage) of
 plant species participating in experimental plots during four consecutive
 springs (collected in April) in a field experiment where abiotic (water
 availability) and biotic (tussock of the perennial plant Stipa
 tenacissima, biological soil crust dominated by crustose lichens, and bare
 soil) were manipulated, along with the availability of seeds in the soil
 (seed-free soil vs. homogenised natural soil containing the complete seed
 bank in the system). From the cover values recorded in the field, we also
 analysed other features of the community (i.e., species richness and
 diversity) and the functional properties of assemblages (using a database
 developed in previous studies on the same gypsophilous community). ###
 Files and variables #### File: Cover4y.xlsx **Description.** The dataset
 shows cover data (visually estimated, in percentage) of each species
 participating in assemblages during four consecutive springs. The first
 column indicates the identification of each plot (assemblage), the
 following five ones refer to independent variables (biotic factors,
 watering, seed availability in the soil, pair -the design was built on the
 basis of paired plots with different soil seed treatments-, and spring).
 The other columns show plant species cover. Note that some variables
 (watering) and levels (laid_down and dead stipa tenacissima tussocks) were
 not included in this study. **Variables** * **Biotic filters.** Levels:
 intact= intact stipa tenacissima tussocks; laid_down= alive laid down
 stipa tenacissima tussocks (not included in the study); dead= dead,
 standing up stipa tenacissima tussocks (not included in the study); BSC=
 biological soil crust (pieces of lichens); Bare= bare soil (free of
 perennial plants in the vicinity and bioctusts). * **Watering**. Levels:
 natural= plots not watered (they only received natural rainfall); and
 water= plots which received additional watering (50% of the average
 monthly rainfall; not included in this study). Thus, we worked only with
 plots which received natural rainfall. * **Soil**. Levels: sterile=
 seed-free soil collected in a gypsum quarry near the field experimental
 station; and seeds= homogenised natural soil containing the complete seed
 bank in the system. * **Pair**. Number of each plot forming paired
 samples. * **Year**. Year (April) of assemblage sampling: 2019, 2020,
 2021, 2022. * Next columns: **plant species cover** (dependent variable).
 These data were the source of all information analysed in the study,
 including functional trait analyses.