Effects of plant functional group loss on soil biota and net ecosystem exchange: a plant removal experiment in the Mongolian grassland

1. The rapid loss of global biodiversity can greatly affect the functioning of above-ground components of ecosystems. However, how such biodiversity losses affect below-ground communities and linkages to soil carbon (C) sequestration is unclear. Here we describe how losses in plant functional groups (PFGs) affect soil microbial and nematode communities and net ecosystem exchange (NEE) in a 4-year removal experiment conducted on the Mongolian plateau, the world's largest remaining natural grassland. 2. Our results demonstrated that the biomasses or abundances of most components of the two below-ground communities (microbes and nematodes) were negatively affected by PFG loss and were positively related to above-ground plant biomass. The removal of dominant PFGs (perennial bunchgrasses and perennial rhizomatous grasses) reduced the biomass or abundance of below-ground community components while removal of less dominant PFGs (perennial forbs and annuals/biennials) did not change or increase...