PEW01 Plant species composition and edaphic properties in wallow and non-wallow plots at Konza Prairie

Bison wallows—bare depressions formed by repeated trampling and dust-bathing—introduce fine-scale heterogeneity to tallgrass prairie soils and plant communities. We compared plant communities and edaphic properties of wallows to adjacent non-wallow plots and cattle-grazed plots. Wallows had reduced organic matter and nitrogen but elevated clay and sodium. Non-fenced wallows had lower plant species richness than fenced wallows and all non-wallows. However, wallows supported distinct plant communities, including wetland species in temporary pools. While bison-grazed areas generally had higher plant diversity, wallows added localized variation not found in cattle or fenced plots. Our results suggest wallows function as small-scale ecosystem engineering features, shaping soil conditions and plant composition.野牛踩踏泥洼（bison wallows）——经反复踩踏与沙尘浴形成的裸露洼地——为高草草原（tallgrass prairie）的土壤与植物群落带来了精细尺度的生境异质性。本研究对比了泥洼、邻近非泥洼样地与牛放牧样地的植物群落及土壤理化性质（edaphic properties）。泥洼的土壤有机质与氮含量显著降低，但黏土与钠含量有所升高。未围栏的泥洼的植物物种丰富度低于围栏保护的泥洼以及所有非泥洼样地。但泥洼孕育了独特的植物群落，其中包括临时积水池中的湿地物种。尽管野牛放牧区的植物多样性普遍更高，但泥洼带来了牛放牧样地与围栏保护样地中均不存在的局域生境变异。本研究结果表明，野牛泥洼作为小型生态系统工程特征（ecosystem engineering features），能够塑造土壤环境与植物群落组成。