Human Impacts to River Temperature and Their Effects on Biological Processes: A Quantitative Synthesis1

Hester, Erich T. and Martin W. Doyle, 2011. Human Impacts to River Temperature and Their Effects on Biological Processes: A Quantitative Synthesis. Journal of the American Water Resources Association (JAWRA) 47(3):571‐587. DOI: 10.1111/j.1752‐1688.2011.00525.x Abstract: Land‐use change and water resources management increasingly impact stream and river temperatures and therefore aquatic organisms. Efforts at thermal mitigation are expected to grow in future decades. Yet the biological consequences of both human thermal impacts and proposed mitigation options are poorly quantified. This study provides such context for river thermal management in two ways. First, we summarize the full spectrum of human thermal impacts to help thermal managers consider the relative magnitudes of all impacts and mitigation options. Second, we synthesize biological sensitivity to river temperature shifts using thermal performance curves, which relate organism‐level biological processes to temperature. This approach supplements the popular use of thermal thresholds by directly estimating the impact of temperature shifts on the rates of key biological processes (e.g., growth). Our results quantify a diverse array of human thermal impacts, revealing that human actions tend to increase more than decrease river temperatures. Our results also provide a practical framework in which to quantify the sensitivity of river organisms to such impacts and related mitigation options. Finally, among the data and studies we synthesized, river organisms appear to be more sensitive to temperature above than below their thermal maxima, and fish are more sensitive to temperature change than invertebrates.     

人工湿地净化河道水质的研究进展

人工湿地是近年来国内外应用较多、发展较快的一种污水处理技术,本文从国内外人工湿地净化河水的技术应用出发,列举了人工湿地处理河水污染的效果和优势,并对湿地净化河水效率影响较大的湿地植物、填料、气候条件以及湿地构造4个因素进行了比较、分析和总结,最后对人工湿地净化河道水质进行了展望。     

跨界流域环境管理与预警——欧洲经验与启示

工业革命以后,欧洲流域的污染事故进入高发期,欧洲各国以流域为单位,共同商讨对策,联合开展治理工作,使流域水环境得到了很大的改善.目前,欧洲对流域的管理已经形成了一套较为科学、成熟的模式.针对中国水环境污染事故频发的状况,总结了莱茵河流域管理模式和多瑙河流域预警系统的发展经验,对构建中国流域范围内环境预警系统提出了相关思...     

Nutrient Loadings to Streams of the Continental United States from Municipal and Industrial Effluent1

Maupin, Molly A. and Tamara Ivahnenko, 2011. Nutrient Loadings to Streams of the Continental United States From Municipal and Industrial Effluent. Journal of the American Water Resources Association (JAWRA) 47(5):950‐964. DOI: 10.1111/j.1752‐1688.2011.00576.x Abstract: Data from the United States Environmental Protection Agency Permit Compliance System national database were used to calculate annual total nitrogen (TN) and total phosphorus (TP) loads to surface waters from municipal and industrial facilities in six major regions of the United States for 1992, 1997, and 2002. Concentration and effluent flow data were examined for approximately 118,250 facilities in 45 states and the District of Columbia. Inconsistent and incomplete discharge locations, effluent flows, and effluent nutrient concentrations limited the use of these data for calculating nutrient loads. More concentrations were reported for major facilities, those discharging more than 1 million gallons per day, than for minor facilities, and more concentrations were reported for TP than for TN. Analytical methods to check and improve the quality of the Permit Compliance System data were used. Annual loads were calculated using “typical pollutant concentrations” to supplement missing concentrations based on the type and size of facilities. Annual nutrient loads for over 26,600 facilities were calculated for at least one of the three years. Sewage systems represented 74% of all TN loads and 58% of all TP loads. This work represents an initial set of data to develop a comprehensive and consistent national database of point‐source nutrient loads. These loads can be used to inform a wide range of water‐quality management, watershed modeling, and research efforts at multiple scales.     

变化环境下北江下游年径流量的加权马尔可夫链预测

在气候变化和人类活动的影响下,西北江的水文环境发生了重大变化,导致北江下游的来水条件发生变化。采用斯波曼检验（Spearman’s rho test）和Mann-kendall法系统地分析了北江下游的年径流量的变化趋势和变异情况,在此基础上建立了北江下游变化环境下年径流量的加权马尔可夫链预测模型。结果表明：西北江近50年来的大规模联围筑闸、大规模无序采掘河床泥沙等剧烈的人类活动,导致北江下游三水水文站年径流量在1990年左右发生了变异;所建立的加权马尔可夫链预测结果表明,从变异后的序列中统计出来的状态＂转移概率＂矩阵,能准确地反映出环境变化后年径流量之间的关系,所建立的加权马尔可夫链法预测变化环境下的年径流量是可行的,预测效果也比较好;按文章确定的分级标准,依现有的资料信息推断,环境发生变化后,在未来长期过程中,北江下游出现平水年的机会最大,但年际间的丰枯波动概率也不小。这一结果值得水资源管理部门注意。     

太湖西岸河网沉积物中重金属污染特征及风险评价

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.     

波流式生态滤床氨氮去除效果及其微生物群落结构分析

利用波流式生态滤床处理受污染的河水,考察了其对氨氮的去除效果和沿程污染物转化情况,并采用扫描电镜、高通量测序手段解析了波流式生态滤床不同时间和位置基质上生物膜的细菌群落组成,分析了波流式生态滤床小试反应器中硝化细菌和反硝化细菌的分布特点,以探讨其去除氨氮的机理.结果表明,反应器稳定运行以后,对氨氮平均去除率为74.83%,基质表面可以观察到大量微生物,不同时期优势细菌有较大不同.反应器前部主要发挥硝化作用,中部发挥反硝化作用,硝化菌的分布呈现上多下少、前多后少的特点,使得氨氮在前端被快速去除;中部以黄杆菌属(Flavobacterium)为代表的反硝化菌丰度较高,促进了反硝化作用的发挥,降低了出水中总氮浓度;不同部位样品中细菌多样性差别不大,微生物种群多样性随着水流方向呈现先增加,到后段减少的趋势.     

一种多介质层波形潜流人工湿地处理重污染河水试验

我国河流污染严重,城市黑臭水体的比率日益增加。人工湿地作为一种高效低耗能的绿色处理技术,已被广泛应用于污染河水的治理。通过对比分析分层装填复合填料的多介质层波形潜流人工湿地和单一砾石填料的普通人工湿地处理重污染河水的效果,研究了特种基质填料强化脱氮除磷作用以及不同水力负荷条件的影响。试验结果表明:在水力负荷为0.2 m~3/(m~2·d)时,普通湿地对COD、NH3-N、TN和TP的去除率分别达到55.95%、77.85%、39.80%和54.94%;多介质层湿地对COD、NH3-N、TN和TP的去除率分别达到58.52%、75.99%、67.08%和57.31%。在水力负荷为0.5 m~3/(m~2·d)时,普通湿地对COD、NH3-N、TN和TP的去除率分别达到68.46%、90.73%、42.13%和53.70%;多介质层湿地对COD、NH3-N、TN和TP的去除率分别达到69.61%、89.94%、77.58%和68.63%,其脱氮效果明显好于普通湿地。以复合填料包分层装填的波形潜流人工湿地系统具有良好的脱氮除磷效果,有很好的推广应用价值。     

基于WebGIS的水环境模拟关键技术研究

近年来随着水环境模拟领域的发展出现了较多水环境数学模型,目前日益成熟的WebGIS技术是使模型使用变得简单化和直观化的一大途径.是在通过Flex和ArcGIS Server搭建WebGIS系统平台的基础上,利用PHP进行WebGIS和水环境模拟模型的数据交互,实现系统平台和数值模型的松散耦合.用户在浏览器端进行模型输入条件的设置,模型在远程服务器端进行运行计算,反馈的模拟结果通过RIA在WebGIS中进行多元化动态展示.该方法对一般模型具有适用性,可降低模型使用门槛,提高模拟结果展示和分析能力.     

太湖流域上游平原河网污染物综合衰减系数的测定

改善太湖水质需要削减上游河流进入太湖的污染物总量.为了探求太湖流域上游平原河网的自净能力,开展原位实验测定了枯水期高锰酸盐指数、氨氮(NH_4~+-N)、总氮(TN)和总磷(TP)的综合衰减系数,根据河道的水力特征对综合衰减系数进行了修正,并利用一维稳态水质模型对修正前后综合衰减系数的可靠性进行了验证.结果表明,高锰酸盐指数、NH_4~+-N、TN和TP的综合衰减系数分别为:0.0296~0.4106、0.0224~0.3564、0.0137~0.3046和0.0555~0.5725 d~(-1).可靠性验证表明高锰酸盐指数、NH_4~+-N、TN和TP综合衰减系数修正前的平均相对误差分别为8.39%、14.40%、11.43%和19.22%,修正后的平均相对误差分别为10.65%、14.34%、11.37%和19.24%.修正前后高锰酸盐指数、NH_4~+-N、TN和TP的平均相对误差均小于20%且变化不显著,表明综合衰减系数的测定结果能够为太湖流域上游平原河网的污染物总量控制管理提供科学参数;也表明枯水期的水力条件对综合衰减系数的影响较小.