Data Package Summary    View Full Metadata

This data set is also available on the Dryad Digital repository (link : https://doi.org/10.5061/dryad.59kv753)

This dataset was created for investigating the biotic resistance hypothesis, that is, the idea that species‐rich communities are more successful at resisting invasion by exotic species than are species‐poor communities. It has been argued that native–exotic richness relationships (NERR) are negative at small spatial scales and positive at large scales, but evidence for the role of spatial scale on NERR has been contradictory. However, no formal quantitative synthesis had previously examined whether NERR is scale‐dependent across multiple studies, and previous studies on NERR have not distinguished spatial grain and extent, which may drive very different ecological processes Therefore, a global systematic review was carried out to create this dataset, which includes 204 individual cases of observational (non‐experimental) NERRs from 101 publications. Further, the above-mentioned hypotheses were investigated using a hierarchical mixed‐effects meta‐analysis, which showed that NERR was indeed highly scale dependent across studies and increased with the log of grain size. Also, no clear patterns of NERR across different spatial extents were found, suggesting that extent plays a less important role in determining NERR than does grain, although there was a complex interaction between extent and grain size. Almost all studies on NERR were found to have been conducted in North America, western Europe, and a few other regions, with little information on tropical or Arctic regions. NERR was also found to increase northward in temperate regions and vary with longitude. These results were published in the paper titled Correlation of native and exotic species richness: a global meta‐analysis finds no invasion paradox across scales (Peng et al. 2018), which represents the first global quantitative analysis of scale‐based NERR.