Effect of freshwater inflow on macrobenthos productivity in minor bay and river-dominated estuaries, FY01 : final report

The current contract is the first of a planned five-year study with the goal to determine the importance of freshwater inflow in maintaining benthic productivity in minor bays and river dominated systems. Minor bays are defined as those small bays that do not have direct freshwater inflow via a major river, but do have inflow from runoff or other indirect sources. Only a few rivers in Texas flow directly into the Gulf of Mexico, and these are also part of the subject study. The current project follows successful completion of a long-term study of large, or major open bays in Texas. The focus of this final report is on East Matagorda Bay. Biological data is added to a previous sediment study on nitrogen losses to compile a complete view of that system. Sampling was also begun for a long-term study of two river-dominated systems, the Rio Grande and Brazos River. The current report goes into lesser detail for this data as it will be subject to a fuller treatment in future.

Benthos abundance, biomass, and diversity will be measured to assess inflow effects on ecosystem productivity. In addition, relevant water quality variables (i.e., salinity, temperature, dissolved oxygen, nutrients, and chlorophyll) will be measured during each sampling period to assess inflow effects on the overlying water, which affects benthos. The first year study was performed to initiate a long-term study of the two river estuaries (Brazos and Rio Grande) and complete a study of East Matagorda Bay, a minor bay.

From University of Texas at Austin Marine Science Institute ... to Texas Water Development Board

Interagency cooperative contract, TWDB contract no. 2001-483-362

October 2001

"December 2001"--Cover leaf