Linkages between aboveground and belowground community compositions in grasslands along a historical land-use intensity gradient.

Background and aims: Improving our understanding of ecosystem responses to land-use intensification requires explicit consideration of linkages between aboveground and belowground communities. Here, we explore linkages between plant, soil microbial and nematode community compositions along a historical land-use intensity (hLUI) gradient.Methods: We used co-inertia analysis to investigate linkages between each paired community composition in 33 grasslands with similar hydrology and soil texture but contrasting hLUI and associated soil chemical properties (e.g. pH, phosphorus). We estimated the percentage cover of plant species, identified nematodes to genus level, and analysed the microbial community using phospholipid fatty acid (PLFA) profiling.Results: Plant and nematode communities were more strongly linked as compared to either community's links with microbes, although all pairwise comparisons were significant. Linkage strength did not depend on the degree of hLUI. We found significant variations in plant and nematode, but not in microbial, community compositions along the hLUI gradient.Conclusions: Large changes in soil fertility associated with hLUI have led to shifts in vegetation community composition matched by changes in the composition of different soil communities, or vice versa. The nematode community seems to be more responsive to vegetation composition than other trophic groups. Additional research in an experimental setting will elucidate the mechanisms underpinning the observed relationships. [ABSTRACT FROM AUTHOR]