Relationship between Water Quality and the Community Structure of Epiphytic Diatoms in a Mississippi Bayou

摘要

Epiphytic diatoms were collected from the leaves of submerged angiosperms belonging to the genera Potamogeton, Zannichellia, and Najas in Grand Plains Bayou, Hancock County, Mississippi from March through September 1980. Extremely heavy rainfall caused this bayou to be an essentially freshwater system for the first five months of the study. Salinity finally rose to 6 parts per 1000 by weight in August and to 13 parts per 1000 by weight in September. The bayou waters were acidic to neutral for most of the study and concentrations of dissolved nitrogen and phosphorus were low, indicating that the system was relatively unproductive. During the freshwater period species diversity (H') and the number of taxa in a sample (S) were very low. After saltwater intrusion H' increased beyond 2.0 and S exceeded 20.