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1.
河流水质评价中模糊数学评价法的应用与比较   总被引:8,自引:0,他引:8  
陈奕  许有鹏 《四川环境》2009,28(1):94-98
选择2005年6个典型日(1月12日、3月10目、5月10日、7月13日、9月8日和11月10日)的水质,运用两种模糊数学评价法对浙江西苕溪流域港口断面的水质进行评价并作比较。第一种数学评价法采用较为简单的单因素模糊综合评价法,另一种采用多级模糊数学评价法。评价结果表明,1月12日、3月10日和11月10日的水质达到国家Ⅰ类水质标准;而5月10目的水质相对最差。比较两种评价方法,单因素模糊综合评价法对单个因素的影响敏感,特别是超标值对最后的相对隶属度贡献大;而多级模糊评价法综合各个因素来评价现状水质,因而反映出水质的综合情况。结合港口断面的特点分析水质变差的原因,结论是:流域农业劳作带来的面源污染物质进入港口断面使得该断面在农作高峰期水质较差;同时,断面的水资源短缺问题较为严重,导致水环境容量较小,污染物较难稀释扩散。  相似文献   

2.
为分析小流域水质评价方法的准确度和适应度,以小安溪流域2017年和2018年的监测数据为基础,利用单因子评价法、综合指数评价法、内梅罗污染指数法和加拿大水质指数法进行水质评价,利用等标水质分析的思想对比了四种方法的评价准确度。评价结果显示:单因子评价法更适合评价水质分布较均匀的流域,内梅罗污染指数法要更为客观一些,加拿大水质指数法更适合较大的、评价指标较多的流域。综合指数评价法是最适合小流域水质评价的。其结果为小流域水质评价方法选择提供了借鉴。  相似文献   

3.
四川升钟水库水质评价及污染负荷分析   总被引:2,自引:0,他引:2  
选取高锰酸盐指数(CODMn)、五日生化需氧量(BOD5)、总氮(TN)、总磷(TP)4项监测指标,采用单因干评价法、综合污染指数法、内梅罗污染指数法、模糊综合评价法及水质标识指数法对升钟水库2004~2010年水污染特征进行分析与评价,结果表明:水质标识指数法比较适合升钟水库水体富营养化评价;单因子水质标识指数显示,水库主要污染物为总氮(TN)、总磷(TP),基本呈现富营养状态;2008年水质最差,2010年水质达到Ⅱ类标准;7年Iwq的平均值Ave(Iwq)=3.393,Ave(Iwq)未达到国家Ⅱ类水质标准。近7年综合水质标识指数(Iwq)在不同时点上具有高-低演化规律,总体趋向好转。通过计算2006年N、P污染负荷,TN、TP入库主要源于水产养殖,其贡献率分别为:55%、82%,升钟水库TN、TP是合理容量的1.97~2.32倍。应严格控制水库网箱肥水养殖。研究结果对指导升钟水库水污染防治与水资源管理具有重要的意义。  相似文献   

4.
利用综合水质标识指数法,参照湖泊(水库)富营养化评价指标,选取总氮(TN)、总磷(TP)、高锰酸盐指数(CODMn)、叶绿素(a)、透明度(D)等5项指标,对升钟水库2006--2010年水体富营养化进行评价。结果表明:综合水质指数,埘排序为3.231_2010〈3.741_2009〈4.042_2007〈4.35_2006〈4.652_2008(指数越大,水质越差);升钟水库近5年综合水质标识指数在不同的时点上具有“高-低”演化规律,总体趋向好转;2008年的指数最大,富营养化最严重,2006-2008年水质指数呈波动变化,2009年、2010年水质有所改善;综合水质标识指数k随时间t变化的二次函数关系式为:I_wq=-0.1372t2+550.8t-552742;升钟水库水体氮、磷严重超标。  相似文献   

5.
邛海富营养化状态评价初探   总被引:2,自引:0,他引:2  
以邛海2006年四个水质监测点水质监测资料为基础,采用综合营养状态指数法对邛海营养状态进行综合评价,通过评价得出:邛海水质已呈中富营养化状态。同时根据邛海水质营养状况,提出了一定的措施建议:限期治理上游污染源;调整养殖结构;限制邛海周边低档次、小规模的度假村、农家乐的建设;采用生物修复等措施。  相似文献   

6.
为研究郪江流域遂宁段水环境质量,对郪江干流和8条支流开展了现场调查和定期监测。采用内梅罗综合污染指数、断面类别比例法和水环境质量指数对流域水质进行了综合分析。利用综合营养状态指数对水源地水体富营养化进行了评价。结果表明:郪江流域遂宁段水质不能够达到《地表水环境质量标准》(GB3838-2002)Ⅲ类标准要求,水质为轻度污染,枯、平水期水质优于丰水期。支流水质较差,加重了干流水体负荷。流域部分饮用水源地为Ⅳ类水质,同时表现为轻度富营养化。研究成果为水质改善提供理论依据和水生态环境质量稳定达标提供技术支撑。  相似文献   

7.
对宝鸡市东沙河流域7个断面进行采样,分析污染因子特征,采用单因子评价法、综合污染指数法和改进的内梅罗指数法相结合,对东沙河水质进行综合评价。结果表明:七个断面流域主要污染物为COD,氨氮次之。东沙河流域磷、化学需氧量、氨氮浓度呈下降趋势,pH含量缓慢上升。河流域上游水质为Ⅲ类,中下游水质为Ⅴ类。河流上游污染因子为COD、主要污染物为工农业废水。中下游主要污染物为COD、氨氮。工业废水排放量是影响流域水质的主要原因。生活污水、固体废弃物以及农业废水溢流量对河流水质的变化也有重要作用。  相似文献   

8.
黑龙滩水库生态环境及水体富营养化研究   总被引:1,自引:1,他引:1  
邓仕高 《四川环境》1993,12(2):63-69
本文以黑龙滩水库1989-1991年水质实测资料为依据,采用综合污染指数法对水库水质进行了定量分析,同时用卡森指数对水库富营养化程度进行产评价。针对库区特点及周围污染源排放现状,分析了水库水质受到的潜在威胁,提出了水源保护的措施及对策。  相似文献   

9.
丁雪卿 《四川环境》2010,29(2):47-51
以《地表水环境质量标准》(GB3838-2002)为基础,选取溶解氧、高锰酸盐指数、CODC r等20项指标作为评价指标,采用内梅罗污染指数法的改进方法对内江市5处饮用水源地进行综合评价,并将评价结果与单因子评价法进行比较。结果表明,内江市5处饮用水源地水质状况较好;内梅罗污染指数法的评价结论比单因子评价法的评价结论更科学、合理和全面的反映综合水质状况。  相似文献   

10.
黄山市新安江流域水环境质量评价与管理措施   总被引:1,自引:0,他引:1  
新安江是我国江南跨省级行政区的一条重要河流,其水质和水量对下游浙江省的生态安全和资源支持具有重要作用。针对安徽省黄山市境内新安江流域内存在的主要水环境问题,采用尼梅罗水质指数和超标加权法对新安江流域水环境质量进行了评价和分析。结果表明,新安江流域水环境质量整体较好,达到Ⅱ、Ⅲ类标准,大部分河段均能满足地表水环境功能要求;下游河段水质略差,但符合地表水Ⅲ类标准。在此基础上,提出了新安江流域水环境管理措施。  相似文献   

11.
Lohit is a major tributary of the river Brahmaputra in India and is famous for its rich and diverse fish fauna. The river has a difficult terrain, but has high hydropower potential. A large number of storage-based hydropower plants are envisaged on this river in the near-future. This study aims at presenting the existing diverse fish fauna in Lohit river basin. A total of 74 fish species are identified in this river basin and can be classified into seven orders, 20 families, and 52 genera. Further, it has been highlighted that there are seven species which have been categorized as endangered, 12 species are categorized to be vulnerable, three species have been categorized as data-deficient, and the remaining species are in the least concern category. It is expected that the construction of proposed storage-based power plants in this basin will affect the flow and storage characteristics, as well as the temperature of the water, which, in turn, will affect the rich fish fauna. This study emphasizes the need for preparing a comprehensive plan for the adoption of appropriate in situ conservation measures, as well as an awareness program, so as to save the rich and diverse fish fauna of Lohit river basin.  相似文献   

12.
随着一系列梯级水电站的建成运行,因上游电站泄水引起下游河道型水库水体中总溶解气体(TDG)过饱和,导致库区鱼类患气泡病甚至死亡的风险增加。针对河道型水库过饱和TDG释放预测问题,建立河道型水库的纵向一维过饱和TDG释放预测模型,研究不同洪水条件下河道型水库在变水位运行条件下的水动力学和过饱和TDG释放特性,分析了过饱和TDG沿程释放和代表性断面的TDG过程,探讨了横断面滩地区域的水深变化和鱼类补偿水深的满足性。结果表明降低来流的TDG水平是减小其不利影响的重要手段,在来流TDG饱和度一定时,河道型水库适当以高水位运行能够为滩地区域鱼类提供足够的躲避水深。本文结果对梯级电站优化调度以减缓TDG影响的研究和方案实施提供了技术支撑,在梯级水电开发河流的水生态保护方面具有重要意义。  相似文献   

13.
Several models have been developed to assess the biological integrity of aquatic systems using fish community data. One of these, the target fish community (TFC) model, has been used primarily to assess the biological integrity of larger, mainstem rivers in southern New England with basins characterized by dispersed human activities. We tested the efficacy of the TFC approach to specify the fish community in the highly urbanized Charles River watershed in eastern Massachusetts. To create a TFC for the Charles River we assembled a list of fish species that historically inhabited the Charles River watershed, identified geomorphically and zoogeographically similar reference rivers regarded as being in high quality condition, amassed fish survey data for the reference rivers, and extracted from the collections the information needed to define a TFC. We used a similarity measurement method to assess the extent to which the study river community complies with the TFC and an inference approach to summarize the manner in which the existing fish community differed from target conditions. The five most abundant species in the TFC were common shiners (34%), fallfish (17%) redbreast sunfish (11%), white suckers (8%), and American eel (7%). Three of the five species predicted to be most abundant in the TFC were scarce or absent in the existing river community. Further, the river was dominated by macrohabitat generalists (99%) while the TFC was predicted to contain 19% fluvial specialist species, 43% fluvial dependent species, and 38% macrohabitat generalist species. In addition, while the target community was dominated by fish intolerant (37%) and moderately tolerant (39%) of water quality degradation, the existing community was dominated by tolerant individuals (59%) and lacked intolerant species expected in the TFC. Similarity scores for species, habitat use specialization, and water quality degradation tolerance categories were 28%, 35% and 66%, respectively. The clear pattern of deviations from target conditions when observing fish habitat requirements strongly suggests that physical habitat change should be a priority for river enhancement in the Charles River. Comparison of our target and existing fish communities to those from a comprehensive study of Northeastern fish assemblage responses to urban intensity gradients revealed very similar results. Likewise, comparison of our TFC community and affinity scores to those of other TFCs from similar regions also yielded similar results and encouraging findings. Based on the positive results of these comparisons, the utility of the findings from the inference approach, and the widespread adoption of the TFC in the Northeast US, it appears that the TFC approach can be used effectively to identify the composition of a healthy fish community and guide river enhancements in both highly urbanized and non-urbanized streams and rivers in the Northeast US.  相似文献   

14.
本文详细介绍县级环境监测实验室设计原则和理念,并结合作者自己站环境监测实验室建设的实际,对实验室新大楼建设平面布局、实验室排风、实验室供电、实验室纯水系统、实验室特殊气体系统等部分的设计进行了简单介绍,并提出了相关优选方案,为县级同规模环境监测实验室的建设提供借鉴作用。  相似文献   

15.
Effects of changing environments of riverside mangroves, coastal land uses, and water quality on fish communities were studied in Bangphra and Thaprik creeks, Trat Bay, Thailand. Regression analysis revealed that fish species richness in the wet season had a negative relationship with water transparency, nitrate, and phosphate and a positive relationship with zooplankton. In the dry season, species richness had a negative relationship with nitrate and phosphate and a positive relationship with salinity, pH, and zooplankton. Abundances and species richness of fish declined over distance from downstream to upstream in both creeks. Riparian mangroves and water quality also declined with distance upstream in both creeks. Results from one-way analysis of variance and Tukey’s HSD test revealed that the highest zooplankton volume with the lowest amounts of nitrate and phosphate were observed at the downstream station in both creeks in each season. Low zooplankton volume with high amounts of nitrate and phosphate were found at the midstream and upstream stations of the creeks. The midstream and upstream stations of Bangphra Creek had low to moderate abundance of mangroves along the riversides, whereas shrimp farms were mainly found along the riversides at the midstream and upstream stations of Thaprik Creek. Correlation analysis results of land-use types and the significant habitat factors were discussed. This study found that mangrove degradation, shrimp farming, and residential and agricultural areas altered water quality and the health of fish habitats, causing the decreases in fish abundance and species richness.  相似文献   

16.
Summary The extent of surface water acidification in Northern Europe and in Britain is reviewed and information is given on the degree to which changes in water quality appear to have influenced fish populations. The relationship between water quality and fish has been clarified by laboratory exposures, demonstrating that levels of calcium and aluminium, as well as acidity, are important for fish. It is not easy, however, to transpose laboratory findings to the field. Other determinants of a fishery should not be ignored — they include morphological and physical characteristics of lakes and streams, and biological characteristics such as food supply and species interactions.The recovery or restoration of fisheries in acid waters is crucially dependent on replacement of calcium and reduction of aluminium to bring the water quality into a range suitable for fish. While reduction of sulphur emissions, or of the atmospheric deposition of all acid generating materials, may be expected to have some effect on lake sulphate concentrations, the degree to which acidity might be realistically reduced is quite uncertain.Dr. G. D. Howells was, until recently, Head of Biology at the Central Electricity Research Laboratories of the United Kingdom's Central Electricity Generating Board (CEGB). Her previous experience includes her first degree, obtained in New Zealand, a subsequent research degree from the University of Cambridge, and three years at the University of New York studying the effects of power station siting on the Hudson River. She has a wide experience of studying pollution problems. This paper was presented at the Institution of Environmental Sciences Conference,An Update on Acid Rain, November 1984, and is published by permission of the Central Electricity Generating Board.  相似文献   

17.
It has been frequently demonstrated that mercury (Hg) concentrations in fish rise in newly constructed hydroelectric reservoirs in the Northern Hemisphere. In the present work, we studied whether similar effects take place also in a tropical upland reservoir during impoundment and discuss possible causes and implications. Total Hg concentrations in fish and several soil and water parameters were determined before and after flooding at Rio Manso hydroelectric power plant in western Brazil. The Hg concentrations in soil and sediment were within the background levels in the region (22-35 ng g(-1) dry weight). There was a strong positive correlation between Hg and carbon and sulphur in sediment. Predatory fish had total Hg concentrations ranging between 70 and 210 ng g(-1) f.w. 7 years before flooding and between 72 and 755 ng g(-1) f.w. during flooding, but increased to between 216 and 938 ng g(-1) f.w. in the piscivorous and carnivorous species Pseudoplatystoma fasciatum, cachara, and Salminus brasiliensis, dourado, 3 years after flooding. At the same time, concentrations of organic carbon in the water increased and oxygen concentrations decreased, indicating increased decomposition and anoxia as contributing to the increased Hg concentrations in fish. The present fish Hg concentrations in commonly consumed piscivorous species are a threat to the health of the population dependent on fishing in the dam and downstream river for sustenance. Mercury exposure can be reduced by following fish consumption recommendations until fish Hg concentrations decrease to a safe level.  相似文献   

18.
/ Fishes and their habitats were sampled in Harland Creek, Mississippi, for 3 years to compare the relative value of three types of bank treatment in an incised, warmwater stream. Semiannual samples were collected from 10 reaches: 3 reaches protected by each of the three types of protection (longitudinal stone toe, stone spurs, and dormant willow posts) and an unprotected, slowly eroding bend. Protection of concave banks of bends had no measurable effect on the habitat quality of downstream riffles. Although bends and adjacent downstream riffles were faunistically similar at the species level, catostomids and centrarchids were more dominant in pools and smaller cyprinids more dominant in riffles. Reaches with willow posts were slightly deeper than the others, most likely because of geomorphic factors rather than bank treatment. Mean water surface widths in reaches stabilized with stone spurs were 40% to 90% greater than for other treatments, and current velocities were greatest in reaches with stone toe. Patterns of fish abundance and species diversity did not differ significantly among treatments. However, principal components analysis indicated that the fish species distribution associated with the untreated reference site was distinct. Reaches stabilized with stone spurs supported significantly higher densities of large fish and higher levels of fish biomass per unit channel length than reaches with other bank treatments, generally confirming previous research in the region. Initial costs for spurs were comparable to those for stone toe and about three times greater than for willow posts.  相似文献   

19.
水电站建设对水环境容量的影响研究   总被引:3,自引:0,他引:3  
曹玲玲  邓云 《四川环境》2010,29(1):51-55
水电站建设影响河道水环境容量。为研究水电站建设对水环境容量的影响,本文以汉阳水电站为例,采用一维水环境容量计算方法,计算相应河段建库前后水环境容量,并分析了降解系数的取值对水环境容量的影响。结果表明建库后水流流速减缓,污染物降解时间增加,从而增大水环境容量;而水流流速减缓,降解系数减小,从而减小水环境容量。在二者共同作用下,汉阳水电站建库前后水环境容量变化不大。  相似文献   

20.
ABSTRACT Two lakes having similar soil types were studied to determine the effects of age and water fluctuations on plankton, benthos and fish populations. Bluff Lake is an older man-made lake which is drawn down in the mid-summer. Oktibbeha County Lake is a young lake and the water levels are maintained. Chemistry data from the two lakes indicate that their chemical properties are very similar. Neither lake would be considered very fertile. Net plankton populations in Bluff Lake and Oktibbeha County Lake were comparable when analyzed on a number of organisms per liter basis. Fluctuations of water levels did not seem to have an effect on the net plankton populations. The benthic population in Bluff Lake is slightly higher than that found in Oktibbeha County Lake. This is true for both numbers and weight per square meter. The species composition of benthic organisms in the two lakes were similar. Based on one-acre samples from each lake, Bluff Lake has a more balanced fish population than does Oktibbeha County Lake. Neither, however, seems to support populations of game fish in which a high percentage of these are in the available or harvestable range. Both lakes contain high populations of gizzard shad.  相似文献   

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