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<br />00lG <br /> <br />Methods of Analyses <br /> <br />Water. - The procedures used for the chemical <br />examination of water are described in "Standard <br />Methods" of the American Public Health Associ- <br />ation. (1975) 12]. The following is a summary <br />of these methods: <br /> <br />Total dissolved solids - Filter through a <br />0.45-l'm filter and evaporate at 105 0 C <br /> <br />Calcium. magnesium. and hardness - EDT A <br />(ethylenediaminetetraacetic acidl titri- <br />metric methods <br /> <br />Sodium and potassium - Flame photometric <br />method <br /> <br />Hydrogen ion concentration - pH meter <br /> <br />Sulfate - Gravimetric method <br /> <br />Chloride - Argentometric method <br /> <br />Heavy Metals. - Flame and flameless atomic ab- <br />sorption spectroscopy were used to analyze for <br />the selected heavy metals. <br /> <br />Phosphorus and Nitrogen. - Automated spec- <br />trophotometric techniques were used in the <br />analyses for phosphorus and nitrogen com- <br />pounds. <br /> <br />Preparation of Fish Livers for Heavy Metals <br />Analyses. - All fish liver samples were dried to a <br />constant weight in a vacuum oven at 60 0 C. <br />They were digested in 2 mL of concentrated <br />H,SO. and 2 mL of HNO, for 4 hours on a steam <br />bath or until the solutions were clear. All solu- <br />tions were diluted to 200 mL with distilled water <br />and analyzed as described under heavy metals <br />analyses. <br /> <br />Invertebrates. - Preserved macroinvertebrate <br />samples were analyzed in the Bureau's Engineer- <br />ing and Research Center laboratory. The <br />organisms were identified to the family or genus <br />levels, and the number of individuals per group <br />was determined. Two indices were calculated <br />for each sample: diversity (d) and equitability lei. <br />Equations and methods basic to the calculations <br />are discussed below: <br /> <br />Diversity was calculated from the equation <br />(Wilhm and Dorris, 1968 [1671): <br /> <br />d= <br /> <br />S n. n. <br />~ -.!... log, -1.. <br />i= 1 N N <br /> <br />[1] <br /> <br />where s = <br /> <br />total number of genera in the <br />sample <br />number of organisms in the ,th <br />genus <br />total number of organisms in the <br />sample <br /> <br />n. = <br />, <br /> <br />N= <br /> <br />The resultant d is a dimensionless number, theo- <br />retically in the range from zero to any positive <br />number. but in practice seldom greater than 10 <br />(Dills and Rogers. 1974 [3911. Usually the <br />higher numbers indicate better water quality. It <br />is best to compare relative d within a system <br />rather than attempting to identify the degree of <br />pollution or habitat quality using only the calcu- <br />lated d value. In this study, changes in d indicate <br />undesirable effects on water quality of some in- <br />flows and improvements of water quality by <br />other inflows. <br /> <br />Equitability (e) was determined from the follow- <br />ing relationship ILloyd and Ghelardl, 1964 <br />[98J ): <br /> <br />s' <br /> <br />e <br /> <br />s <br /> <br />where s = total number of genera in the <br />sample <br />s' = number of genera expected from <br />a community that conforms to <br />the MacArthur "broken- <br />stick" model of species distri- <br />bution Itabulated values) <br /> <br />The calculated e is a dimensionless number, <br />commonly ranging from 0 to 1. In samples con. <br />taining only a few individuals with several <br />genera represented, however. the value of e will <br />be greater than one IWeber. 19731161] ). <br /> <br />Fish. - Fish were collected by electrofishing. <br />then identified. counted. and released. They <br />were identified to the species level and popula- <br />tion estimates were calculated using the follow- <br />ing formula: <br /> <br />19 <br />