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911.
山东省水环境自动监测监控系统数据的应用设计和使用方法 总被引:1,自引:0,他引:1
山东省水环境自动监测监控子系统的主要功能是将全省水质自动站数据利用计算机网络、数据仓库等技术导入到环境监测数据仓库中,实现全省水环境自动监测的统一监控和监测信息的自动管理和发布。本文简单介绍了系统担制中心端监测数据统计应用部分的功能设计和实现方法。 相似文献
912.
四川三台鲁班水库属于大型湖库,多年来除具有特色景观作为旅游景点外,主要用于发展水产养殖业。随着时间的延续,养殖规模的不断扩大,湖库的自净能力越来越差,使有机物污染不断加重,水质越来越差,出现富营养化现象,对水环境造成了不利影响。近年来,为了改变湖库水环境质量,调整转化湖库功能,恢复水环境质量,加强了对其水质的监测,其中的营养状态指标是湖库水环境质量的主要评价指标。评价结果,除秋季和冬季个别月份外,其余各月均有测点达到轻度富营养化及中度富营养化。 相似文献
913.
Liu, Clark C.K. and John J. Dai, 2012. Seawater Intrusion and Sustainable Yield of Basal Aquifers. Journal of the American Water Resources Association (JAWRA) 48(5): 861‐870. DOI: 10.1111/j.1752‐1688.2012.00659.x Abstract: Basal aquifers, in which freshwater floats on top of saltwater, are the major freshwater supply for the Hawaiian Islands, as well as many other coastal regions around the world. Under unexploited or natural conditions, freshwater and the underlying seawater are separated by a relatively sharp interface located below mean sea level at a depth of about 40 times the hydraulic head. With forced draft, the hydraulic head of a basal aquifer would decline and the sharp interface would move up. It is a serious problem of seawater intrusion as huge amounts of freshwater storage is replaced by saltwater. Also, with forced draft, the sharp interface is replaced by a transition zone in which the salinity increases downward from freshwater to saltwater. As pumping continues, the transition zone expands. The desirable source‐water salinity in Hawaii is about 2% of the seawater salinity. Therefore, the transition zone expansion is another serious problem of seawater intrusion. In this study, a robust analytical groundwater flow and salinity transport model (RAM2) was developed. RAM2 has a simple mathematical structure and its model parameters can be determined satisfactorily with the available field monitoring data. The usefulness of RAM2 as a viable management tool for coastal ground water management is demonstrated by applying it to determine the sustainable yield of the Pearl Harbor aquifer, a principal water supply source in Hawaii. 相似文献
914.
Result-oriented approaches to the management of drinking water catchments in agricultural landscapes
Alexander Wezel Maria Zipfer Christine Aubry Fabienne Barataud Alois Heißenhuber 《Journal of Environmental Planning and Management》2016,59(2):183-202
Management of water quality in drinking water catchments is of ongoing, high importance as nitrate concentrations are often still very high. We analysed the Augsburg catchment in Germany, a unique example where a result-oriented approach has been implemented. We investigated the historical evolution of the water protection programme, the result-oriented payment contracts with farmers, and farmer satisfaction with the contracts, based on interviews with the water utility and farmers as well as an analysis of the literature. Today, the water protection programme has been successfully implemented, and a significant reduction of nitrate concentration was achieved due to the following factors: (1) investment of non-negligible amounts of money for high compensation and remuneration payments, (2) different contract options, (3) farmers’ participation in the negotiation process for result-oriented payment contracts, (4) involvement of “outside” people and institutions in negotiation processes, (5) anticipation of starting a programme when nitrate levels were still far below legislative thresholds, and (6) a political and legislative framework allowing direct decisions by a water supplier. 相似文献
915.
呼和浩特市十年地表水环境质量趋势分析 总被引:1,自引:0,他引:1
本文根据呼和浩特市十年来河流水质监测数据,选取高锰酸盐指数(CODMn)、生化需氧量(BOD5)、氨氮、挥发酚、汞、铅和石油类七项指标,运用水质综合指数法(P法),分析呼和浩特市地表水十年来的变化趋势及污染特点,提出了治理地表水污染的思路。 相似文献
916.
利用紫外-可见光谱与三维荧光-平行因子分析法(EEM-PARAFAC),研究了广州市2014年12月~2015年1月大气气溶胶中水溶性有机物(WSOC)和类腐殖质(HULIS)的吸光性和荧光光谱特征.结果表明,广州冬季气溶胶中HULIS的芳香性(SUVA254)、腐殖化程度(HIX)和光吸收效率(MAE365)均高于WSOC.利用EEM-PARAFAC从WSOC和HULIS解析出了类富里酸(C1)、类腐殖酸(C2)和类蛋白(C3)这3种荧光组分.其中类腐殖质组分(C1+C2)分别占WSOC和HULIS中总荧光组分的78%和85%,说明类腐殖荧光组分是WSOC和HULIS的最主要组成,且HULIS富集了更多的WSOC中主要的类腐殖组分.另外,灰霾期的WSOC和HULIS表现出更高的芳香性、腐殖化程度和C2组分,说明灰霾期有助于大分子量吸光性有机质的形成.相关性分析结果显示,WSOC和HULIS的C1组分相对含量与HIX、MAE365、OCsec、K+、SO_4~(2-)和NH_4~+呈现极显著的负相关关系,而C2与它们之间存在极显著的正相关关系.由此说明,WSOC和HULIS中C1的降低和C2的增加会引起它们的腐殖化程度和光吸收能力的增强;同时生物质燃烧排放和二次气溶胶过程可能有助于C2组分的增加. 相似文献
917.
Rosborg I Nihlgård B Gerhardsson L Sverdrup H 《Environmental geochemistry and health》2006,28(3):215-229
The water chemistry of 20 municipal water treatment plants in southern Sweden, representing various bedrock situations, and water qualities, were investigated. Four water samples, raw and treated, were collected from each plant and analyzed by predominantly ICP-OES and ICP-MS at four occasions from June to December, 2001. The concentrations of Ca, Mg, K, Na, HCO3 and a number of micronutrients, varied considerably in treated waters from the studied plants (ranges; Ca: 9.1–53.7 mg L−1, Mg: 1.4–10.9 mg L−1, K: 1.1–4.8 mg L−1, Na; 5.4–75.6 mg L−1, HCO3: 27–217 mg L−1). The elimination of Fe and Mn from raw water was efficient in all treatments investigated, giving concentrations in treated waters below the detection limits at some plants. Softening filters gave waters with Ca-concentrations comparable to the softest waters in this study. Adjustment of pH by use of chemicals like lye, soda or lime, modified the consumer water composition significantly, besides raising the pH. It was estimated that drinking water contributed to approximately 2.2–13% of the daily Ca uptake, if the gastrointestinal uptake efficiency from food and water was estimated to be around 50%. The corresponding figures for Mg was 1.0–7% and for F 0–59%. None of the studied elements showed any significant time trends in raw or treated waters during the follow-up period. The concentrations of potentially toxic metals such as Al, Pb and U were low and did not indicate risks for adverse health effects (ranges; Al: 0.5–2.3 μg L−1, Pb: 0–0.3 μg L−1, U: 0.2.5 μg L−1). 相似文献
918.
分别以l-辛基-3-甲基咪唑六氟磷酸离子液体([C8MIM][PF6])和三辛基氧化膦(TOPO)作为萃取剂与辅助萃取剂,建立了中空纤维膜辅助的两相液液微萃取-高效液相色谱测定环境水体中水杨酸(Salicylicacid,SA)的新方法.通过对中空纤维膜种类、萃取剂、供体相体积、供体相pH、离子强度和萃取时间相关参数进行优化,获得了较高的富集倍数(1653倍).方法的检出限为0.1μg.L-1,线性范围为0.5—1000μg.L-1.方法对实际样品的加标回收率为89.6%—102.4%,可应用于环境水体中痕量SA的测定. 相似文献
919.
三唑磷农药废水厌氧处理可行性研究 总被引:2,自引:0,他引:2
采用厌氧流化率工艺处理在唑磷农药废水,必须降低原水中NH3-N含量,调整营养比例,当COD:N:P=(180~200):5:1时,在中温厌氧消化条件下,COD含量可从4170mg/l,去除率约50%,沼气产率达到0.256m^3/m^3.d。因此,把厌氧处理作为好氧处理的预处理单元,能确保整个处理系统出水达标。 相似文献
920.
太湖西岸河网沉积物中重金属污染特征及风险评价 总被引:1,自引:5,他引:1
为研究太湖西岸河网沉积物中重金属污染特征及风险,调查了丰-平-枯3个水期19个点位8种重金属的含量,结果表明,沉积物中重金属浓度顺序为ZnCrCuPbNiAsCdHg,其中Cd、Cu、Zn、Pb、Ni明显高于其环境背景值,除As外,其余7种重金属平水期含量高于丰水和枯水期.地累积指数(I_(geo))和潜在生态指数(RI)评价表明,研究区沉积物中Cd属于中等污染程度和中等生态风险,Cd对RI贡献率为35%,重金属生物毒性不利影响评价值(mP EC-Q)范围为0.12~0.76,平均值0.30,表明研究区发生生物毒性不利影响的可能性为15%~29%,工业与生活混合区点位S2从污染程度、生态风险、生物毒性不利影响和主成分评价的污染及风险均最大,表现出多种重金属的协同污染,这与其周围污染排放特征一致,为该区域河流沉积物中重金属污染控制提供依据. 相似文献