Environmental influences on plant species composition in ground-water seeps in the Catskill Mountains of New York

Ground-water seeps in the Catskill Mountains are important water sources fo r streams and often have different chemistry than nearby surface water. Man y studies have shown correlations between water chemistry and plant species composition in wetlands, but there are no such studies in the Catskill Mou ntain ground-water seeps. The objective of this study was to identify the c hemical and physical environmental variables that most strongly influence p lant species composition in seeps. Environmental variables and plant specie s abundance were measured at 33 seeps. TWo-way INdicator SPecies ANalysis w ith analysis of variance and Canonical Correspondence Analysis showed that plant species composition is determined primarily by water depth and alkali nity/acidity complex gradients. Growing season changes in water chemistry w ere not shown to influence the plant community.