An Evaluation of Selenium Concentrations in Water, Sediment, Invertebrates, and Fish from the Republican River Basin: 1997–1999

The Republican River Basin of Colorado,Nebraska, and Kansas lies in a valley which contains PierreShale as part of its geological substrata. Selenium is anindigenous constituent in the shale and is readily leached intosurrounding groundwater. The Basin is heavily irrigated throughthe pumping of groundwater, some of which is selenium-contaminated, onto fields in agricultural production. Water,sediment, benthic invertebrates, and/or fish were collected from46 sites in the Basin and were analyzed for selenium to determinethe potential for food-chain bioaccumulation, dietary toxicity,and reproductive effects of selenium in biota. Resultingselenium concentrations were compared to published guidelines orbiological effects thresholds. Water from 38% of the sites (n = 18) contained selenium concentrations exceeding 5 g L^-1, which is reported to be a high hazard for selenium accumulation into the planktonic food chain. An additional 12 sites (26% of the sites) contained selenium in water between 3–5 g L^-1, constituting a moderate hazard. Selenium concentrations in sedimentindicated little to no hazard for selenium accumulation fromsediments into the benthic food chain. Ninety-five percent ofbenthic invertebrates collected exhibited selenium concentrationsexceeding 3 g g^-1, a level reported as potentially lethal to fish and birds that consume them. Seventy-five percent of fish collected in 1997, 90% in 1998, and 64% in 1999 exceeded 4 g g^-1selenium, indicating a high potential for toxicity andreproductive effects. However, examination of weight profilesof various species of collected individual fish suggestedsuccessful recruitment in spite of selenium concentrations thatexceeded published biological effects thresholds for health andreproductive success. This finding suggested that universalapplication of published guidelines for selenium may beinappropriate or at least may need refinement for systems similarto the Republican River Basin. Additional research is needed todetermine the true impact of selenium on fish and wildliferesources in the Basin.     

Cadmium and Lead Levels in Fish (Tilapia Nilotica) Tissues as Biological Indicator for Lake Water Pollution

Cadmium and lead were determined in different tissues (muscle,gill, stomach, intestine, liver, vertebral column and scales) of Tilapia nilotica from the High Dam Lake, Aswan (Egypt) to assess the lake water pollution with those toxic metals. Fish samples were chosen from different ages and weights to be analyzed along with samples of the aquatic plant(Najas armeta), sediment and lake water.The results showed that cadmium and lead concentrations were higher in fish scales and vertebral column than in the other parts of the fish. Cadmium and lead levels in High Dam lake water and fish (Tilapia nilotica) were a result of the pollution which uptakes from aquatic plants, sediments andgasoline containing lead that leaks from fishery boats. Tilapia nilotica fish was used as a good bio-assay indicator for the lake pollution with cadmium and lead. The fish musclesin this study were in the safety baseline levels for man consumption.     

博斯腾湖水质矿化度模型及预测研究

根据博斯腾湖１９８５～１９９５年水质监测数据和出入湖水量等水文数据观测值，采用水质扩散模型和盐量平衡关系推导出博斯腾湖大湖区（简称博湖）水质矿化度模型，并预测了几种情况下博湖水质矿化度及近几年变化趋势，分析了影响博湖水质矿化度的主要因素，为博湖的近期和远期环境保护规划、环境管理等提供科学依据．     

哈密地区环境中^220Rn子体α潜能浓度所致居民剂量估算

用ＳｔｒａｎｄｅｎＥ．推荐的测量方法对哈密地区环境空气中２２０Ｒｎ子体α潜能浓度测量结果表明，室内、外平均值分别为５６．１和１０．２（×１０－７Ｊ·ｍ－３）。室内外２２０Ｒｎ／２２２Ｒｎ子体α潜能浓度比值分别为０．８４和０３２。２２０Ｒｎ子体所致居民有效剂量当量为２２８μＳｖ·ａ－１（集体有效剂量当量为０．９×０２ｍａｎ·Ｓｖ）。     

车载巡测在区域射频电磁环境质量监测与表征中的应用分析

对北京中央电视塔周围25 km²区域电磁环境质量分别进行了射频的网格法手工监测和车载巡测自动监测，通过SPSS软件等对两种监测方法获取的数据进行了统计对比分析，发现两组数据在总体水平及数值分布特征上较为接近，因此车载巡测监测可以替代网格法监测。以车载巡测数据为基础，绘制了实测数据的道路电磁地图，利用插值法绘制了区域电磁地图，对区域电磁环境质量进行了直观表征。从回应公众关注和城市电磁规划出发，建议今后可利用车载巡测监测加强时域和频域的监测。     

潜水含水层水位观测孔水位伪变化的观测与分析

结合CIRP试验场包气带的介质结构及渗透性特征，在S9孔进行了短期的孔中水位、孔口气压和温度测量，测量结果表明，观测孔水位波动与大气压变化有关，水位波动具有伪变化。水位伪变化对于试验场潜水位的监测有一定影响，因此，应对带有伪变化的水位观测结果进行必要的修正，以反映潜水位的真实动态。     

Monitoring of diazinon concentrations and loadings,and identification of geographic origins consequent to stormwater runoff from orchards in the Sacramento River watershed,U.S.A

Diazinon contamination of California's rivers has resulted in placing several rivers on the federal Clean Water Act § 303d list of impaired waterways. Impaired water body listing requiresthe development of Total Maximum Daily Loads (TMDL). Previous studies identified stormwater related diazinon pulses in California rivers. This study was conducted to monitor diazinonconcentrations in the Sacramento River watershed after rainfallevents, to ascertain whether pulses could be identified and, ifconcentrations of concern were observed, to estimate loadings anddetermine geographic origins of the insecticide. TMDL developmentrequires knowledge of contaminant sources, loadings, and geographic origins. Flow and diazinon concentrations peaked in the Sacramento River at Sacramento after the three largest stormsduring January and February 1994. Diazinon concentrations peakedconsequent to each of three storms. Diazinon concentrationsmeasured in the Sacramento River at Sacramento exceeded theCalifornia Department of Fish and Game acute and chroniccriteria for protection of aquatic life during January andFebruary for nine and nineteen days, respectively. Multipleexceedances were observed throughout the watershed. Diazinon loading and geographic origin differed with each of the three storms. The design of this study provides a useful template for others attempting to identify loadings and sources of contaminants in surface waters and to rectify aquatic ecosystemcontamination from various land use practices.     

Temperature and Concentration Effects in Biomonitoring of Organic Air Pollutants

Up to now only very few studies in biomonitoring of organic air pollutants have been published taking into account the strong influence mean temperatures have on the accumulation process into plants during the course of the exposition. Temperature governed sorption as well as the plants vitality pose a major source of uncertainty making inter-study comparisons difficult. Different surface-to-volume ratios of plant foliage lead to strongly varying concentration effects in different plant species. Moreover a plants content of waxes and lipids must be considered in order to relate xenobiotic concentrations to the compounds being most efficient in the bioaccumulation process. Some of these factors are evaluated in regard to the use of plants as biomonitors for organic air pollutants. Another aim is to deduce the mean ambient gas phase concentrations from PAH concentrations determined in the biomonitor plants using vegetation-air partitioning coefficients which have been corrected for temperature dependent sorption as well as the plants lipid content. Restrictions of such approaches and methods of biomonitoring in general are discussed.     

Obligations to animals are based on rights

Some feminist philosophers criticize the idea of human rights because, they allege, it encapsulates male bias; it is therefore misguided, in their view, to extend moral rights to non-human animals. I argue that the feminist criticism is misguided. Ideas are not biased in favour of men simply because they originate with men, nor are ideas themselves biased in favour of men because men have used them prejudicially. As for the position that women should abandon theories of rights and embrace an ethic that emphasizes care: women who made this choice would not so much liberate themselves from the patriarchy as they would conform to its representation of women as emotional, subjective and irrational. There is, then, no good reason to withhold ascribing rights to non-human animals, based on the criticisms of rights made by some feminists.Some of the material in the discussion of the feminist critique of rights originally appeared in my The Case for Animal Rights: A Decade's Passing inA Quarter Century of Value Inquiry: Presidential Addresses of the American Society of Value Inquiry, edited by Richard T. Hull, pp. 451–455. Amsterdam and Atlanta, GA: Rodopi, 1994. These passages are reprinted with the permission of the editor and publisher, whose thoughtful co-operation is gratefully acknowledged.