A global database for metacommunity ecology, integrating species, traits, environment and space

Abstract

The use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. Although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across ecosystems, taxa and spatial scales. To address this gap, we collated 80 datasets from trait-based studies into a global database for metaCommunity Ecology: Species, Traits, Environment and Space; "CESTES". Each dataset includes four matrices: species community abundances or presences/absences across multiple sites, species trait information, environmental variables and spatial coordinates of the sampling sites. The CESTES database is a live database: it will be maintained and expanded in the future as new datasets become available. By its harmonized structure, and the diversity of ecosystem types, taxonomic groups, and spatial scales it covers, the CESTES database provides an important opportunity for synthetic trait-based research in community ecology.

Fig. 1

Structure of the CESTES database. The database includes 80 Excel files for 80 datasets. Each dataset is composed of four matrices of data stored in spreadsheets: comm (species abundances [n = 68] or presences/absences [n = 12]), traits (species traits), envir (environmental variables), and coord (spatial coordinates). Each dataset also includes a DataKey (description of the entries of the Data tables), a Notes sheet (contact information for the dataset, and, when relevant, processing information), a Species list, and a Site list. The grey components can be the original data matrices, and additional information and do not appear in all the datasets, depending on specific needs (see Methods - Data processing section).

Fig. 2

Overview of the CESTES database. Upper panel: Map of the 80 dataset locations over the globe (blue spots) (the orange smaller spots represent the 10 ancillary datasets from ceste, the non-spatial supplement of CESTES - see the Methods section); the four coloured polygons represent four datasets that are covering continental extents. The background world map is from OpenStreetMap contributors. Bottom panel: Bar plots and histogram describing the content of the database in terms of: study group, ecological realm, level of human disturbance, and spatial extent of the study.

Fig. 3

Success rates of the data search and request. Barplot showing the percentage of the different outputs from the data collection process. Percentages are calculated from a total of 139 datasets identified as eligible for the CESTES database (based on literature search and networking). Incomplete data mainly refer to the datasets that had no spatial coordinates (ceste), included unsolved issues, or provided insufficient metadata information. (“Agreed but did not share” refers to authors who replied positively to the first request but then never sent their data despite reminders because e.g., they did not find time to prepare the data).

Fig. 4

“DataKey” structure and example of metadata information in CESTES datasets. A description is given when the variable full name is not self-explanatory or when potentially relevant information was available. Possible empty cells are due to lack of information that could not be recovered from the original publication nor from the data owners.

Fig. 5

Data content of the CESTES database. Distribution of the number of environmental, site, species and trait variables across the datasets.

Fig. 6

Power check of the CESTES datasets with respect to fourth-corner analysis’ requirements. After the Fig. 4a from Dray & Legendre. Plot of the CESTES datasets (blue dots) according to their number of sites and number of species compared to three power thresholds observed in the fourth-corner simulation study from Dray & Legendre. The dashed rectangle represents the range of values tested in the simulations of Dray & Legendre. The curves represent their observed thresholds of Type II error rates - red = 30%, orange = 10%, yellow = 5%, grey = 0%. The datasets that fall below these thresholds are theoretically exposed to respectively 30%, 10%, 5% or 0% chance to fail to detect significant TERs with fourth-corner analysis although these exist. The figure shows that the majority of the CESTES datasets fall in a medium (70%) to very good (>95%) power zone (Power = 100% − Type II error).