Data underlying the publication: Drivers of the geographical distribution of nematode-based indices across Europe

Abstract

This dataset contains values for nematode-based indices (NBIs) of soil food-web functioning across Europe. Specifically, it includes values for the structure index and enrichment index, which reflect food-web connectivity and nutrient enrichment, respectively. These values were derived from the NemEu database*, which holds raw nematode abundance data at genus and family level. The dataset represents a subset of locations selected for analysis, spanning arable, managed grassland, non-managed grassland, and shrubland or forest systems. Alongside the NBI values, the dataset provides estimates of environmental properties representing the classical soil-forming factors (climate, organisms, relief, and parent material), as well as indicators of disturbance, all sourced from openly available spatial products.<br>The data was used to compare NBI values across European environmental zones within different land-use types. This analysis revealed that NBIs varied significantly across environmental zones, though the patterns differed considerably among land-use types. Most notably, environmental zone had a significant effect on the structure index in non-managed systems, whereas in intensively managed arable systems, the influence of land use overrode naturally occurring variability.<br>The environmental properties were used to construct a multigroup structural equation model, quantifying how different factors drive NBI values across environmental zones. Results showed that the relationships between NBIs and environmental properties varied considerably by zone, with some properties even showing opposing directional effects depending on the environmental context. Disturbance indicators had a significant impact on NBIs across a wide range of environmental zones.<br>*The full NemEu database will be made publicly available upon publication of an accompanying data paper, currently under review.