[Responses of plant functional traits to micro-topographical changes in hilly and gully region of the Loess Plateau, China].

Plant functional traits are closely tied to the performance of plants in specific microenvironments, and reflect their ability to adapt to those microenvironments. In areas with complex topography, analyzing the responses of plant functional traits to microtopographical changes is crucial to understanding the adaptive strategies of plants in diverse environments. This paper analyzed fluctuations in soil nutrients as well as correlations between plant functional traits and changes in topography at the family and community levels in selected natural vegetation communities in the foreststeppe zone of the loess hilly and gully region in Loess Plateau of China. Significant differences in plant functional traits were primarily driven by the phylogenetic background or species composition of the community. Slope aspect exerted less impact while slope positions had no significant effect on plant traits at the community level. No significant changes in plant functional traits were observed with changes in topography at the community level. However, leaf nitrogen and root nitrogen contents of Leguminous and Compositae species differed significantly With slope positions. The root tissue density of Graminaceous species differed significantly with slope positions. Root density exhibited significant positive correlations with soil nutrient and carbon contents at the community level. Both leaf nitrogen and root nitrogen contents of Leguminous species were positively correlated with soil phosphorus content, while leaf nitrogen and root nitrogen contents of both Graminaceous and Compositae species were significantly positively related to soil nitrogen content. The results demonstrate the different responses of species of different families to changes in micro-topography and their distinctive adaptive strategies to the environment.