| Physicochemical conditions and zooplankton of the lower Neches River system were surveyed from February, 1992, to January, 1993. The zooplankton community was made up of thirty-eight taxa of rotifers, six taxa of copepods, and nine taxa of cladocerans. Seven rotifer taxa, two copepod taxa, and one cladoceran comprised 5% or more of their respective taxonomic groups and were defined as being dominant. The population dynamics of all the dominant taxa followed typical seasonal patterns similar to those reported in other studies. Physicochemical parameters were within normal limits in most areas. Low dissolved oxygen and pH were noted at the bottom of Pine Island Bayou during the summer, and high conductivity occurred in the estuarine stations sampled. Both the zooplankton and physicochemical data were influenced by Steinhagen Reservoir and possibly Lake Sam Rayburn in the northern portion of the study area and Sabine Lake and the Gulf of Mexico in the southern portion. |
