Many wetland environmental gradients structure plant community composition, yet controls of plant community composition within rich fens, botanically diverse groundwater-fed wetlands, are still incompletely understood. Porewater chemistry and plant community composition were recorded for eight calcareous rich fens encompassing both calcium carbonate and calcium sulfate geological inputs in the Central New York State region. As expected, porewater sulfate and sulfide concentrations were, on average, higher for wetlands overlying calcium sulfate than for wetlands overlying calcium carbonate. However, within-wetland heterogeneity in porewater chemistry was high. Moss species density, moss cover, and total plant cover decreased with increased sulfide. Moss, dicot, and total cover also had a negative relationship with calcium. There were a number of species-level responses to calcium, sulfide, phosphorus, and ferrous iron. Plant height had a positive relationship with nitrogen. The strength and relative importance of some plant responses to sulfide and calcium in the current regional study differed from a previous sub-hectare scale study. The observed decrease in some metrics of site-level plant diversity with increased sulfide variability across fens highlighted the need to characterize species-environment relationships across spatial scales.

许多湿地环境梯度构成植物群落组成，但对植物区系，富植物的地下水喂养的湿地内植物群落组成的控制仍未完全了解。记录了纽约州中部地区八种富含钙的碳酸钙的孔隙水化学和植物群落组成，其中包括碳酸钙和硫酸钙的地质输入。如所期望的，覆盖硫酸钙的湿地的孔隙水硫酸盐和硫化物浓度平均高于覆盖碳酸钙的湿地。然而，湿地内部的孔隙水化学非均质性很高。随着硫化物含量的增加，苔藓物种密度，苔藓覆盖率和植物总覆盖率降低。苔藓，双子叶植物和总覆盖率也与钙呈负相关。钙，硫化物，磷和亚铁对物种有多种反应。株高与氮呈正相关。在当前的区域研究中，某些植物对硫化物和钙的反应的强度和相对重要性与先前的亚公顷规模研究不同。观察到的一些站点水平植物多样性的指标随着with中硫化物变异性的增加而减少，这凸显了在空间尺度上表征物种与环境关系的必要性。