Biodiversity is a keystone of multi-functionalities of terrestrial ecosystems, including productivity, element and energy cycling. As one of key drivers of soil-vegetation feedbacks, how plant litter effects on seedling establishment and plant composition are well-known. However, it is unclear how litter manipulate on plant diversity in native grasslands. Thus, we tested the litter mass gradients (0, 100, 200, 400 or 600 g m-2) of E. nutans, K. setchwanensis and L. virgaurea which was the dominant species of three community succession stages, respectively, effects on plant species diversity in alpine meadow on the Qinghai-Tibet Plateau (QTP).
Results/Conclusions
Depending on the species and mass, litter addition had significantly negative effects on the species richness of community and positive effects on Shannon-winner index, evenness index, effective number of species and functional diversity (P<0.05), but no impact on species dominance (P>0.05). Moreover, species richness of forbs was significantly reduced by litter addition (P<0.05), while graminoids species richness was relatively constant across all the mass gradients of three kinds of litter (P>0.05). The Shannon-winner index, evenness index, effective number of species and functional diversity was significantly (P<0.05) higher at 400 g m-2 of litter than other levels. Litter of L. virgaurea effect on functional diversity was stronger (P<0.05).
Our study highlighted that species composition and mass of litter played an important role in maintaining grassland plant diversity and thereby ecosystem functions, and litter mass contributed more to plant diversity than litter species composition. Livestock grazing regulating litter species composition and mass should not be ignored at sustainable grassland management in the world.