Interactions between soil characteristics, environmental factors, and plant species abundance: A case study in the karst mountains of Longhushan Nature Reserve, southwest China

The ability to manage and restore plant communities in the face of human-induced landscape change may rely on our ability to predict how species respond to environmental variables. Understanding this response requires examining factors or their interactions that have influence on plant and resource availability. Our objective was to analyze the relationships between changes in plant abundance and the interaction among environmental habitat factors including soil, geological (rock type), and other environmental variables in the Longhushan karst mountains ecosystem. Species density and dominance were examined using ANOVA, ANCOVA, and Generalized Linear Models to establish the single or combined effects of these groups of factors. The results showed that trends in abundance were mainly affected by rock type (related to the percentage content of dolomite and calcite), soil characteristics in association with topography. Both plant indices were higher in dolomite dominated areas and varied positively with moisture, and elevation, but negatively with organic matter, while density also increased with slope degree. The results demonstrate that significant variations in species abundance was produced with the combination of variables from soil, geological, and environmental factors, suggesting their interaction influence on plants. We postulate that spatial variations in plant abundance in karst ecosystem depends on the carbonate rock type in addition to water and nutrient availability which are mainly controlled by topography and other factors such as soil texture and temperature. The study suggests that in karst areas carbonate rock type, in addition to local environmental variables, should be taken into account when analyzing the factors that have impact on plant communities.