Effect of Soil Factors on Shrub Communities in the Central Subtropical Climate

Abstract

Background Shrub communities play a crucial role in forest restoration, soil and water conservation, and maintaining ecological balance in terrestrial ecosystems. However, the influence of environmental factors on the distribution characteristics of shrub plants, particularly in the subtropical region of China, remains poorly understood. Materials and methods Two subtropical areas with similar dimensions in southern Jiangxi and northeastern Guangxi, China were examined. We compared species composition, diversity and life forms in two subtropical regions, and quantified the niche width of the same species using Levins index (Bi). Principal Coordinates Analysis (PCoA) and Redundancy Analysis (RDA) were employed to comprehensively explore the relationship between shrub community composition and environmental factors. Results Southern Jiangxi (with 100 recorded shrub species) and northeastern Guangxi (with 108 recorded shrub species) exhibit comparable species richness in their respective shrub communities. Southern Jiangxi had higher species diversity and a more pronounced dominance of certain species compared to northeastern Guangxi. Additionally, northeastern Guangxi had a higher proportion of aboveground-shoot plants and underground-shoot plants compared to southern Jiangxi. The niche width and niche overlap of the same species exhibit significant differences between the two regions. Low similarity in species composition between their respective shrub communities while RDA analysis highlighted significant correlations between soil physicochemical factors (C, N, P, pH), slope aspect with species composition emphasizing variations in explanatory power across different environmental factors. Conclusion Soil factors exert a significant influence on the structure and species composition of shrub communities in subtropical climates, underscoring the intricate interplay between soil properties and vegetation dynamics within ecosystems.