The dominance of Ligularia spp. related to significant changes in soil microenvironment

Abstract

Exploring how plants adapt to and change the surrounding environment has become essential to understanding their survival strategies and co-evolution mechanisms. Ligularia virgaurea and Ligularia sagitta are the two most common species in the alpine grazing ecosystems of the eastern Qinghai-Tibetan Plateau (QTP) and becoming increasingly dominant. Studies have suggested that overgrazing has allowed Ligularia to gain a competitive advantage by changing plant community structure, which is often closely related to the soil environment. However, we don’t fully understand the soil environment changes during this process, and the underlying mechanisms have not been explored. Therefore, we investigated plant community characteristics, soil fertility and soil microbial diversity in the L. virgaurea and L. sagitta communities on the eastern QTP. Ligularia spp. significantly changed the plant community by reducing biomass, vegetation coverage, abundance, and biodiversity, and the effect of L. sagitta on the plant community was stronger than that of L. virgaurea. In the plant communities dominated by L. virgaurea and L. sagitta, soil nutrients and soil microbial communities changed significantly. Aggregated boosted trees analysis revealed that soil Mg levels had the greatest relative influence on the structure and diversity of the soil microbial community. Our study provides data and a theoretical basis for revealing the survival strategies of L. sagitta and L. virgaurea and, provides a basis for weed management in grazed ecosystems.