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Show such as salinity and temperature on these rates need to be identified. Society can influence the system by supplying nutrients and toxicants. The nutrients supply energy to the system which in abundance can produce dominance by a specific organism or species and disrupt the entire ecosystem. Toxicants may repress growth, cause death, or interfere with reproduction at any level of the ecosystem. The effects of proposed alterations of the present system cannot be assessed until a knowledge of the effects on the ecosystem of changing the salinity of the lake, or adding nutrients, toxicants and other pollutants is available. The brine shrimp and brine fly are two main organisms of concern to other users of the lake. The cause of the reduced brine shrimp winter eggs hatch needs to be studied. The reduction may be related to a shift in the reproductive process of the brine shrimp or may indicate a possibly more severe problem of a decline in the brine shrimp population. Related to this, research needs to be performed on the tolerance ( survival) of brine shrimp at various salinity levels and the conditions which cause the shrimp to produce viable winter eggs. Eliminating the brine shrimp could create serious water quality problems because they filter algae from the lake. The brine fly is very important as waterfowl feed but must be controlled in certain recreational areas. A research need is to identify the dominant species and population of flies produced at various salinity levels. Collins of the University of Ontario and the University of Utah is involved in a three year study of the most important species of brine fly in the lake. If the interactions between the brine fly, the ecosystem, and the lake enviroment can be defined methods of control which do not severely disrupt the ecosystem can be identified. Presently the major social uses of the lake affected by its ecosystem are the brine shrimp industry, recreation, and wildlife. Possible impacts between the ecosystem and the mineral extraction industry and recreation, besides the noxious insect problem, need to be identified so that the effect of disrupting the present ecosystem on these uses can be understood. For example, dominance of the ecosystem by algae could create a situation where their concentration would discourage swimming in the lake. A complete list of research needs identified for the biotic system is given in Table 10. Water Quality Aspects The hydrologic characteristics of Great Salt Lake amplify the water quality considerations. Being a terminal lake there are few outflows for pollutants carried into the lake and the continual buildup of pollutants must be addressed. The ultimate level of various pollutants which the ecosystem and lake users can tolerate is thus important. Because of the diversified uses and the unique hypersaline conditions, it has been difficult for the state to determine a set of water quality standards for the lake. The water quality of the lake inflows is monitored by the USGS, the Environmental Protection Agency, and the State Division of Health. Thus, the quality of the inflow to the lake is fairly well documented. Currently there is not systematic gathering of water quality data within the lake except for total dissolved solids and its ionic components. A few short term data collection projects are reported in the literature which were concerned mainly with obtaining information on other water quality parameters of the lake. Lin et al. ( 1972) reported on detailed vertical profiles of temperature, dissovled oxygen, conductivity, and pH values measured at 17 south arm stations during the summer of 1972. This was the first detailed study of the vertical variation of these parameters. The authors reported typical values of dissolved oxygen for the upper brine layer as 3.5 ppm to 1.5 ppm and " invariably" zero for the lower brine layer. The Kennecott Copper Corporation in cooperation with the UGMS has taken an initial look at heavy metals pollution of the south arm and their findings will be available as a forthcoming report. This study charted the present inflow of heavy metals from all the streams, established the concentration of heavy metals in the brine and sediments at 12 locations in the lake, and looked at the chemical fate of heavy metals in the lake. The results of this study should provide direction for future research and data needs on heavy metals. As part of the Weber River 208 Water Quality Study, data are being gathered on the water quality of streams in the study area, the changes of water quality which occur in the marsh lands, and the distribution of water quality parameters in the lake. Water quality data are being gathered in Farmington Bay and near the Antelope Island and south shore recreational beaches. Researchers involved with this study realize they are only touching the surface of the entire lake pollution problem but hope the study will indicate the extent of the water quality problem and help in identifying what is most important to study in the future. This type of data gathering needs to be expanded to the entire lake so that present and potential water quality problems can be identified and research in the water quality area given direction. Due to the present lack of information regarding biological and chemical processes in the system, it is difficult to |