Species composition, distribution, and abundance of macrobenthic organisms in the intake and discharge areas of steam-electric generating station before and during initial start-up.

The species composition, distribution, abundance of macro-benthic organisms in the intake and discharge areas of Houston Lighting and Power Company's new Cedar Bayou Generating Station were investigated during the period of October 16, 1969 through December 17, 1970. A modified Birge-Ekman dredge was used at 17 stations with soft substrates. A frame sampler was used at five stations with hard substrates. Each gear was used every 4 weeks, but alternately; with a 2-week time interval between use of the dredge and frame. Data yielded by different gear were treated separately. Hydrological measurements and climatic parameters were also recorded. Stations were classified by general substrate type to test for preferences. The preferred substrate of most species was a mixture of sands, silts, and clays, with very silty and very sandy substrates usually being avoided. Frame stations were also classified by the amount of decaying plant debris present in the substrate. The abundance of many species was directly correlated with the amount of debris present, while abundance of only a few species was inversely related.