Removal of Dominant Species Impairs Nitrogen Utilization in Co-Existing Ledum palustre and Vaccinium uliginosum Communities Subjected to Five-Year Continuous Interruptions

Abstract

Unguided exploitation has impaired the sustainability of natural resources of agronomic non-wood forest plants from understory boglands in boreal forests. The extreme consequences of plant–soil interplay on medicinal plant communities under continuous interruptions need to be understood to implement strategies which can cope with possible ecological degradation. In this study, co-existing Ledum palustre and Vaccinium uliginosum communities were investigated after a four-year interruption of continuous removal of dominant species in stands at Xing’an Mountain. Nitrogen (N) availability was assessed by above-ground biomass and N content in nondominant plants and the biophysiological properties of rhizosphere soil. The removal treatment promoted soil mineral and organic N contents, but also reduced abundances of the soil communities of Rozellomycota phylum (by 82.76%), ericoid mycorrhiza of Meliniomyces varia (by 81.60%) and Phialocephala fort (by 69.54%). Vaccinium uliginosum overcame L. palustre through higher N utilization (biomass/%N) although the latter had higher abundances of soil Odiodendron maius and P. fort. The microbial community attributes accounted for a large proportion of N availability following the removal of dominance. In conclusion, our study demonstrates that understory agronomic plants in northern boglands should no longer be under continuous exploitation. Strategies should be considered to improve the promotion of N uptake by managing local soil microbial communities.