Nitrogen and nitrification in the Houston Ship Channel

The objective of this study was to investigate in detail the transport and interconversion of nitrogen forms in the Houston Ship Channel. Particular attention was given the process of nitrification, the bacterial oxidation of ammonia to nitrate thence to nitrate, whether nitrification occurs in the Channel and, if it does, the reaction rates at which it proceeds. Two sources of data were employed, the historical data of the Texas Water Quality Board, consisting of routine sampling runs of the Galveston Bay Project and the later TWQB monitoring program, and data collected as a part this study, consisting of three sampling runs executed in the Channel in 1976. Supplementary information was also compiled, including antecedent streamflows corrected by drainage area to the confluence with the Channel, and nitrogen loads to the Channel due to municipal and industrial point sources. The data runs of this study included analyses for the population densities of ammonia - oxidizing and nitrite - oxidizing bacteria, determined by an MPN technique. Thus a direct appraisal of the magnitude of the nitrifying populaces could be made and judgements made as to the probability of significant nitrification occurring.