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J.C. Fisher

Publications and source records attributed to J.C. Fisher.

9 recordsLinked to original sources

Arsenic(III) fuels anoxygenic photosynthesis in hot spring biofilms from Mono Lake, California

Phylogenetic analysis indicates that microbial arsenic metabolism is ancient and probably extends back to the primordial Earth. In microbial biofilms growing on the rock surfaces of anoxic brine pools fed by hot springs containing arsenite and sulfide at high concentrations, we discovered light-dependent oxidation of arsenite [As(III)] to arsenate [As(V)] occurring under anoxic conditions. The communities were composed primarily of Ectothiorhodospira-like purple bacteria or Oscillatoria-like cyanobacteria. A pure culture of a photosynthetic bacterium grew as a photoautotroph when As(III) was used as the sole photosynthetic electron donor. The strain contained genes encoding a putative As(V) reductase but no detectable homologs of the As(III) oxidase genes of aerobic chemolithotrophs, suggesting a reverse functionality for the reductase. Production of As(V) by anoxygenic photosynthesis probably opened niches for primordial Earth's first As(V)-respiring prokaryotes.

Science

Hydrologic data for the Salt Bayou estuary near Sabine Pass, Texas, October 1984 to March 1986

The Salt Bayou estuary, located in extreme southeast Texas near Sabine Pass, has been altered by construction of the Gulf Intracoastal Waterway. The waterway has interrupted the historical saltwater-freshwater exchange in this important estuary. This alteration may have had a detrimental effect on fish production because of increased salinity, and on waterfowl production because of lower water levels. There have been proposals to develop water control structures in the major channels that would enable some regulation of the saltwater in order to restore the estuary to its approximate historic state. A cooperative effort was initiated by the Louisiana Cooperative Fish and Wildlife Research Unit, the U.S. Fish and Wildlife Service, the Texas Parks and Wildlife Department, and the U.S. Geological Survey to identify the fish species and their transport mechanisms. The U.S. Geological Survey's part of this effort was to describe the present hydrology of Salt Bayou. The purpose of this report is to present the hydrologic data that were collected during October 1984 through March 1986. The initial data-collection network consisted of stage gages at Keith Lake Pass, the mouth of Salt Bayou, Ten Mile Cut, the Intracoastal Waterway, and Star Lake. A stage gage at the Alligator Bayou pumping plant became available later in the study. After 6 months of data were collected, the Ten Mile Cut gage was moved to Wildcow Bayou. The gages at Keith Lake Pass, the mouth of Salt Bayou, Ten Mile Cut, and Wildcow Bayou were equipped with water-velocity recording equipment. The Keith Lake Pass gage also had temperature and specific-conductance recording equipment. Six 24-hour flow investigations were performed to calibrate the velocity recording equipment and to determine the flow at ungaged sites. Before and after these investigations, specific conductance was measured at 43 sites within the estuary. Precipitation data were obtained from National Oceanic and Atmospheric Administration stations at Port Arthur, Anahuac, and Sea Rim State Park and were used to estimate the contribution of freshwater from rainfall. Evaporation data were obtained from Beaumont Research Station and were used to make estimates of water consumption from evapotranspiration. Wind speed and direction were obtained from the National Oceanic and Atmospheric Administration weather station at Sea Rim State Park.

Open-File Report

Chemical and physical characteristics of water in estuaries of Texas, October 1976-September 1978

The Texas Water Plan (1968) proposes development and utilization of water resources in Texas and includes provision for the use and preservation of water in the estuaries of the State. Management of estuarine waters requires knowledge of the hydrodynamics and of the continuing changes in the chemical and physical characteristics of water in the estuaries. In September 1967, the U.S. Geological Survey and the Texas Department of Water Resources began a cooperative water-resources investigation of the principal estuaries along the Texas coast (fig. 1) except the Rio Grande estuary, which is under the jurisdiction of the International Boundary and Water Commission, United States and Mexico. The objectives of the investigation are to define: (1) The occurrence, source, and distribution of nutrients; (2) the physical, organic, and inorganic water-quality constituents and their areal distribution and time variations; (3) the chemical and physical characteristics of Gulf water that enters the estuaries; (4) the occurrence, quality, quantity, and dispersion of drainage entering the estuarine systems; and (5) the current patterns, directions, and rates of water movement. The coastal waters of Texas are not classical estuaries, but are similar to them in ecosystems and mixing phenomena. A description of various types of estuaries is presented in "Estuaries" edited by Lauff (1967, p. 3-11). The term estuary as used in this report, refers to concomitant water bodies in which streamflow mixes with seawater.

Open-File Report