Linkages between Plant Community Composition and Soil Microbial Diversity in Masson Pine Forests

Abstract

Plant species identity influences soil microbial communities directly by host specificity and root exudates, and indirectly by changing soil properties. As a native pioneer species common in early successional communities, Masson pine (Pinus massoniana) forests are widely distributed in subtropical China, and play a key role in improving ecosystem productivity. However, how pine forest composition, especially the dominance of plant functional groups, affects soil microbial diversity remains unclear. Here, we investigated linkages among woody plant composition, soil physicochemical properties, and microbial diversity in forests along a dominance gradient of Masson pine. Soil bacterial and fungal communities were mainly explained by woody plant community composition rather than by woody species alpha diversity, with the dominance of tree (without including shrub) species and ectomycorrhizal woody plant species accounting for more of the variation among microbial communities than pine dominance alone. Structural equation modeling revealed that bacterial diversity was associated with woody plant compositional variation via altered soil physicochemical properties, whereas fungal diversity was directly driven by woody plant composition. Bacterial functional groups involved in carbohydrate and amino acid metabolism were negatively correlated with the availability of soil nitrogen and phosphorus, whereas saprotrophic and pathogenic fungal groups showed negative correlations with the dominance of tree species. These findings indicate strong linkages between woody plant composition than soil microbial diversity; meanwhile, the high proportion of unexplained variability indicates great necessity of further definitive demonstration for better understanding of forest–microbe interactions and associated ecosystem processes.

Forest Ecosystem Service Trade-Offs/Synergies and System Function Optimization in Karst Desertification Control

“…Forests are the main body of terrestrial ecosystems, providing different types of ecosystem services for the maintenance of life on Earth such as water holding, species diversity, and soil conservation [ 22 ]. In this study, the litter water holding capacity of the H1 community in the karst desertification area is higher than that of other communities, while the soil and canopy water holding capacities are lower than those of other communities; however, the water conservation capacity is the strongest.…”