山东南四湖上级湖水质变化评价(2008-2014年)及成因分析

基于南四湖上级湖6个监测点2008-2014年42个奇数月份的水质资料,选取溶解氧、化学需氧量(COD)、高锰酸盐指数(COD_Mn)、五日生化需氧量(BOD₅)、氨氮、总磷和氟化物作为水质评价的指标.对水质指标的归一化方法进行了改进,采用主成分分析法对6个监测点的水质综合状况进行评价,根据得出的各月综合得分序列分析水质变化趋势.与2000-2007年南四湖上级湖的水质综合状况进行比较,2008-2014年水质明显变好.评价结果表明,同一监测点的水质在不同时间点上有明显变化,同一时间序列不同监测点的水质状况也有不同变化.此外,分析得出南四湖上级湖的主要水质影响指标为COD、COD_Mn和BOD₅.结合评价结果,分析水质变化原因,入湖河流水质状况和湖区底泥是其重要影响因素.     

黄河流域多时空尺度土地利用与水质的关系

为探究不同时空尺度土地利用与水质的相互关系,以黄河流域为研究对象,基于2018年河流水质与土地利用数据,提取3种空间尺度(1000 m河段缓冲区、500 m河岸带缓冲区、子流域)的景观格局指数,结合4个季节河流水质指标,采用冗余分析方法定量探讨土地利用对河流水质的多时空尺度影响,获得水质资源管理最有效的时空尺度.结果表明:(1)在3种空间尺度下,耕地和草地占比最大.斑块密度(PD)在1000 m河段缓冲区尺度下更大,香农多样性指数(SHDI)在3种空间尺度下变化不大;(2)水质指标季节性和空间性存在显著差异,夏季水质优于冬季;(3)土地利用在夏季和1000 m河段缓冲区尺度下对水质影响最显著;(4)不同景观格局指数对河流水质产生的影响不同,耕地面积占比和林地面积占比、未利用地面积占比和SHDI对水质影响最为显著,除了耕地面积占比和PD值的增加会导致水质下降外,其余土地利用指数在大多数时空尺度下均可改善水质.该研究基于不同的时空尺度对土地利用与水质的关系进行定量研究,为合理规划土地资源提供参考,从而保护流域水质安全.     

城镇化下河流水质变化及其与景观格局关系分析——以太湖流域苏州市为例

以河流近域景观格局与水环境质量间的关系为研究对象,基于2001年及2010年两期土地利用类型以及7条典型河流的溶解氧、氨氮、高锰酸盐指数、总磷、总氮5项水质指标,分析城镇化下苏州市河流水质与景观格局之间的关系及其变化规律.结果表明:(1)苏州市河流水质状况总体较差,但呈现一定的好转趋势.(2)河流水质受到城镇用地、旱地及水田的综合影响,并表现出尺度效应.其中城镇用地与旱地对河流水质恶化具有明显的作用,水田则反之.2001-2010年城镇用地及水田对水质的影响程度有所减弱,旱地则增强.(3)蔓延度指数、最大面积斑块比例对河流水质呈现负相关,斑块数量、斑块密度、香农均匀度指数、香农多样性指数则与水质呈现正相关.景观格局对于水质的影响在大范围缓冲区更为显著.研究结果可为苏州水环境管理及太湖流域城市空间开发提供一定的参考依据.     

2012—2018年洪泽湖水质时空变化与原因分析

洪泽湖是南水北调东线工程的重要枢纽.为评估水环境长期变化,于2012-2018年开展逐月水质监测.结合水文气象与淮河水质水量数据,分析洪泽湖水质长期变化趋势及空间分异的驱动因素,结果显示:2012-2018年,洪泽湖总氮、总磷多年平均浓度为1.74和0.081 mg/L,分别为Ⅴ类水和Ⅳ类水,透明度均值为0.48 m,下降趋势不显著,而高锰酸盐指数、叶绿素a多年平均浓度分别为4.13和0.008 mg/L,呈显著下降趋势.在空间分布上,过水区总氮、总磷浓度显著高于成子湖、溧河洼;高锰酸盐指数、叶绿素a浓度则相对较低,透明度则是成子湖较高,溧河洼和过水区相近.3个湖区的叶绿素a浓度下降明显,但过水区的高锰酸盐指数呈上升趋势.洪泽湖与淮河水质相关性分析结果显示,洪泽湖总氮、总磷浓度与淮河水质呈强相关性,特别是过水区各个水质指标与淮河水质均有显著的相关性,而成子湖、溧河洼水质与淮河水质相关性较弱.广义可加模型(GAM)显示,过水区的总氮、总磷浓度等参数与淮河营养盐、高锰酸盐指数及悬浮物浓度变化的关系显著,成子湖和溧河洼的水质指标影响因素差异较大,成子湖、过水区的叶绿素a浓度与高锰酸盐指数相关性较强,而溧河洼的叶绿素a浓度与降水、透明度关系显著.相关性和GAM模型表明淮河对于洪泽湖,尤其是对过水区的水质影响极为明显,是洪泽湖维持较高营养水平和水质空间分异的重要原因.尽管不同湖区叶绿素a浓度下降趋势表明洪泽湖营养状态有所降低,但其氮、磷浓度仍维持在较高水平,存在富营养化风险.应持续关注淮河入湖水质变化,削减污染物输入,压缩湖泊围网、圈圩养殖规模,通过加强水污染防治和水域空间管控保障洪泽湖水环境安全.     

梯级筑坝对黑河水质时空分布特征的影响

为探究梯级大坝建设对河流水质变化规律的影响,将黑河上中游划分为坝上河段、坝下河段及自然河段,于2017年12月-2018年8月选取了24个主要控制断面进行水质调查,并采用多元统计的方法对比分析了不同时空尺度上的水质分布特征.结果表明:黑河上中游水质时空变化的主要影响因子为水温(WT)、pH值、溶解氧(DO)、电导率(EC)、总氮(TN)、总磷(TP)和五日生化需氧量(BOD_5).空间尺度上,WT、EC、BOD_5、高锰酸盐指数(CODMn)、TN等指标具有显著性差异,其中坝上河段受BOD_5、CODMn影响较大,自然河段WT、EC和TN为关键指标,而各个因子对坝下河段水质影响较小.时间尺度上,WT、EC、BOD_5、氨氮与季节变化存在明显相关性,是不同河段水质时间变化的控制因子,且大多数水质因子在非汛期变化最明显.降水、温度、水文条件等季节性影响因素和梯级水库联合运用模式是该区域水质时间差异的主要原因;空间差异主要受祁连、张掖地区外源性污染物排放以及筑坝环境下水动力条件改变而产生的沉积滞留效应和沿程累积效应影响.研究表明,外源性污染源依然是导致水质变差的主要因素,梯级筑坝则是导致水质变差的间接因素.因此控制该区域人类活动所造成的外源性污染源,并针对不同种类污染物的季节变化特征实施合理的水库运行方式是改善水电梯级开发河段水质状况的关键.     

Trends in water quality variations in the Odra River the day before implementation of the Water Framework Directive

This paper contains an account of UN/EEC-sponsored research on water quality monitoring and assessments in the catchments areas of Europe's 10 transboundary rivers. In this context, water quality assessments established on the basis of monitoring data for Poland's rivers are discussed. Consideration is also given to the water quality assessment methods recommended by the EU Directives. The problem has been exemplified by the analysis of water quality variations in the transboundary river Odra in the time span of 1973–2003. For the years 1993–2003, the trends in water quality variations are calculated and the rates of variation are analysed. The points in time when the water quality will have attained the second class purity values are predicted, taking into account the requirements specified in Polish, Czech and German standards. Analysis of the trends in the variations of pollution parameters has revealed that the achievability of good water quality depends on the limit values adopted for the assessment.     

典型网状河网区域土地利用和景观格局对地表季节水质的影响——以江苏省溧阳市为例

地表水质受区域景观组成及其空间配置的影响较大,了解景观特征与水质之间的关系可以极大地提高潜在污染的可预测性和污染物输出的评估能力. 以典型网状河网区域(江苏省溧阳市)为例,研究了土地利用和景观格局特征对地表季节水质的影响. 本研究基于2017年每单月从12个监测断面收集的21个水质指标,首先分析了多尺度缓冲区(500、1000、1500、2000、2500和3000 m)内土地利用和景观格局特征,然后通过主成分分析选取12个指标作为主要水质因子,采用冗余分析确定景观因子对水质指标的最佳影响尺度,最后采用偏最小二乘回归(PLSR)探究了最佳影响尺度下景观因子对季节水质的影响. 结果表明,2500 m缓冲区是该区域景观因子对水质指标的最佳影响尺度,旱季大多数水质指标PLSR模型的显著性和预测能力比雨季强. 雨季大多数水质指标都受园地、林草地、散布与并列指数(IJI)和香农均匀度指数(SHEI)的重要影响,并且这些景观因子与除pH和溶解氧浓度之外的其他水质指标均呈负相关. 在旱季,溶解氧、石油类、化学需氧量、总氮和总磷浓度受土地利用的影响最大; 另外,IJI是电导率、硫酸盐和亚硝酸盐氮浓度的最重要影响因子,而SHEI对硫化物和总悬浮物浓度的影响最大. 此外,景观指数对雨季水质的影响更大. 本研究结果揭示了网状河网区域土地利用/景观格局与季节性水质的关系,为区域水环境管理和景观格局优化提供了科学依据.     

土地利用结构与景观格局对鄱阳湖流域赣江水质的影响

于2015年1月和7月采集赣江干流及支流34个采样点水样,测定电导率、水化学离子、无机氮等水质指标.利用赣江流域2014年30 m分辨率的土地利用数据,以流域景观类型占比表征土地利用结构,景观指数表征景观格局;采用Pearson相关分析、Bioenv分析、Mantle检验与方差分解等方法分析流域土地利用结构与景观格局对赣江水质的影响.结果表明:上游Cl~-、Na~+浓度最高,中游电导率、Cl~-、Na~+、K~+、Ca~(2+)等水质指标最低,下游电导率、HCO_3~-、SO_4~(2-)、Mg~(2+)、Ca~(2+)、NO_3~--N等水质指标最高.居民建设用地是对水质影响最显著的单一土地利用类型.林地、水田与居民建设用地是对水质影响最显著的土地利用类型组合.平均最近邻体指数是对水质影响最显著的单一景观指数,斑块个数、斑块聚集度指数、平均最近邻体指数是对水质影响最显著的景观指数组合.枯水期土地利用结构和景观格局对水质的贡献率分别为41.1%和17.2%,景观格局对水质的贡献率(17.2%)均为和土地利用结构的交互作用,无独立贡献部分;丰水期二者对水质贡献率分别为51%、53%,交互作用部分为37%.以上结果表明,土地利用结构与景观格局都对赣江水质有较大影响,二者的交互作用在该影响中占有重要地位,且枯水期景观格局对水质的影响涵盖在与土地利用结构的交互作用中.     

Comparative evaluation of water quality zonation within Dwarka River Basin,India

This study evaluates the thematic representation of drinking water quality of 211 habitations along the Dwarka River Basin (DRB), West Bengal, India. The dominant water type is Ca–Mg–HCO₃. Statistical analysis of the spatial dataset indicates a clustering pattern (with a nearest-neighbour ratio of 0.368 and Z score of 29.774). Two different techniques, spatial interpolation of water quality index (WQI) and composite water quality index (WQI_C) of physico-chemical constituents, were implemented to compare their performance. The WQI_C indicates approximately 11.68% of the total study area is at non-permissible levels, whereas the normal WQI technique predicts about 1.64% of the area is in non-permissible zones. Spatial water quality zonation by means of the overlay technique was superior to the conventional WQI technique in precisely distinguishing the characteristics of the permissible area with respect to even a single WHO recommended water quality parameter.     

Physico‐chemical Assessment of the Reference Status in German Surface Waters: A Contribution to the Establishment of the EC Water Framework Directive 2000/60/EG in Germany

For the establishment of the EC Water Framework Directive in Germany the physico‐chemical reference conditions of surface waters in Germany had to be determined. The results of the statistical analysis of 3500 data sets of 31 surface water catchment types show that water body types can be aggregated to bogs and bog riverside meadows, saliniferous type, carbonatic‐dolomitic type, sandy‐clayey type, silicatic type, and metallogenic type. The data base allows an assessment of the plausibility of the surface water quality classification and quality targets of the LAWA (Länderarbeitsgemeinschaft Wasser). The investigated reference status of the natural surface waters for the considered elements in the suspended particulate matter, except in metallogenic landscapes, corresponds to the water quality class I of the LAWA. The reference conditions of cadmium and mercury in the total water phase are significantly higher than the quality targets of the LAWA. The evaluated reference data of the other physico‐chemical parameters in the total water phase show, that assessable physico‐chemical parameters refer to a quality class of I, mainly and quality class II, locally. Mainly, the data reached the quality targets of the LAWA. In spite of the hard evaluation criteria to separate reference sites a special enrichment of nitrate and cadmium was found in many German surface water reference catchment types.     

加拿大内陆水的保护

Contrary to general international perception, Canada does not have an unlimited supply of freshwater. However, because Canada has a small population, it does have a generous water allocation on a per capita basis. Nor is Canada immune from water quality problems:its cold continental climate, urbanization and industrial activities all contribute to water quality concerns and deterioration. Generally, the authority to manage water in Canada is held by the country''s provincial governments. The Great Lakes basin is the world''s largest freshwater ecosystem and is located in Canada''s industrial heartland. Water issues, starting with phosphorus in the 1960''s, created international headlines. In the 1970''s toxics became the predominant issue and this led to the Great Lakes Water Quality Agreement which established the ecosystem approach to water quality management. This approach is now the standard approach to water quality management and has been successfully applied to a number of other lake and river ecosystems in Canada. While there have been improvements in the water quality of the Great Lakes much remains to be done on toxic elimination and the large contaminant stores in the sediments. Atmospheric deposition has become a significant source of chemicals from outside the basin The Canadian prairies, the agricultural heartland of Canada, is one major ecozone that has not been selected to have current and potential water quality problems examined by a federal government program. Both the quantity and quality of water in this region are potentially significant factors limiting economic diversification and sustainable development in this vast and ecologically disturbed region.     

Spatial and temporal patterns of the water quality in the Danjiangkou Reservoir,China

Abstract

The three-route South-to-North Water Diversion Project (SNWDP), transferring water from the water-rich Yangtze River and its tributaries to the much drier area of North China for irrigation, industrial and domestic use, has been implemented in China since 2002. Thus, water quality in the Danjiangkou Reservoir, the water source area of the SNWDP's Middle Route, is of great concern. We investigate its water quality from 2004 to 2006 by monitoring some important physical (T, turbidity and SPM) and chemical (DO, pH, alkalinity, TDS, SpCond, ORP, COD_Mn and BOD) parameters and nutrient (nitrogen and phosphorus) contents. Consequently, their spatial and temporal patterns in the reservoir were examined. The results indicate that the water of the reservoir is of a Ca and HCO₃ type, and the major pollutants are nitrogen and COD_Mn. Comparisons among the sampling sites show that water quality increases downstream, implying the self-purification capacity of the reservoir. The reservoir in general has better water quality in the dry season than in the wet season. Integrated basin management would be critical of the water quality in the Danjingkou Reservoir for the interbasin water transfer project.     

Spatial and temporal characterizations of water quality in Kuwait Bay

The spatial and temporal patterns of water quality in Kuwait Bay have been investigated using data from six stations between 2009 and 2011. The results showed that most of water quality parameters such as phosphorus (PO₄), nitrate (NO₃), dissolved oxygen (DO), and Total Suspended Solids (TSS) fluctuated over time and space. Based on Water Quality Index (WQI) data, six stations were significantly clustered into two main classes using cluster analysis, one group located in western side of the Bay, and other in eastern side. Three principal components are responsible for water quality variations in the Bay. The first component included DO and pH. The second included PO₄, TSS and NO₃, and the last component contained seawater temperature and turbidity. The spatial and temporal patterns of water quality in Kuwait Bay are mainly controlled by seasonal variations and discharges from point sources of pollution along Kuwait Bay’s coast as well as from Shatt Al-Arab River.     

Impacts of droughts on low flows and water quality near power stations

ABSTRACT

Power plants often use river waters for cooling purposes and can be sensitive to droughts and low flows. Water quality is also a concern, due to algal blooms and sediment loads that might clog filters. We assessed the impacts of droughts on river flow and water quality from the point of view of power plant operation. The INCA (INtegrated CAtchment) water quality model was coupled with a climate model to create a dataset of flow and water quality time series, using the River Trent (UK) as a case study. The result hints to a significant decrease in flows and an increase in phosphorus concentrations, potentially enhancing algal production. Power plants should expect more stress in the future based on the results of this study, due to reduced cooling water availability and decreasing upstream water quality. This issue might have serious consequences also on the whole national power network.     

Remotely sensed assessment of water quality levels in the Pearl River Estuary, China

In this paper, a method of assessing water quality from satellite data is introduced. The composite pollution index (CPI) was calculated from measured chemical oxygen demand (COD) and nutrient concentration. The relationships between CPI and 240 band combinations of SeaWiFS water-leaving radiance were analyzed and the optimal band combination for estimating CPI was chosen from the 240 band combinations. An algorithm for retrieval of CPI was developed using the optimal band combination, (L₄₄₃ × L₅₁₀)/(L₄₁₂ + L₄₉₀). The CPI was estimated from atmospherically corrected SeaWiFS data by employing the algorithm. Furthermore, the CPI value range for each water quality level was determined based on data obtained from 850 samples taken in the Pearl River Estuary. The remotely sensed CPIs were then transferred to water quality levels and appropriate maps were derived. The remotely sensed water quality level maps displayed a similar distribution of levels based on in situ investigation issued by the State Ocean Administration, China. This study demonstrates that remote sensing can play an important role in water quality assessment.     

Assessing the quality of water of the Araks basin rivers in Armenia

This article deals with the quality of water of tributaries of transboundary River Araks. The performed river water research was underpinned by monthly monitoring data for 2004–2007. As a result of the research, a general characteristic of water quality by basic quality indices and the contents of common ions were given. The impact sources and water quality formation-determining factors were indicated. Geochemical series of heavy metals streams were made up and studied, and dominating elements indicated. As a result of statistical data analysis, correlation dependence between concentrations of a different parameters was indicated.     

梁子湖水质时空格局分析

基于大样本监测数据,从点位、湖区、全局3个层次,对梁子湖水质的季节变化和空间差异进行综合分析,发现梁子湖水质存在显著的季节差异和较大的空间差异:(1)季节上,夏、秋、冬季污染相对较重,春季污染相对较轻;夏、秋季主要污染指标为高锰酸盐指数(COD_(Mn)),冬季为总氮(TN);(2)空间上,东梁子湖和牛山湖污染相对较重,西梁子湖污染相对较轻;东梁子湖主要污染指标为COD_(Mn)、总磷(TP)和TN,牛山湖为COD_(Mn)、TN和氨氮,西梁子湖为COD_(Mn)和TN.研究结果有助于更好地了解梁子湖水质的时空变化特点,进而制定有针对性的保护措施和管理对策.     

Risk minimization in water quality control problems of a river system

Methodologies are presented for minimization of risk in a river water quality management problem. A risk minimization model is developed to minimize the risk of low water quality along a river in the face of conflict among various stake holders. The model consists of three parts: a water quality simulation model, a risk evaluation model with uncertainty analysis and an optimization model. Sensitivity analysis, First Order Reliability Analysis (FORA) and Monte–Carlo simulations are performed to evaluate the fuzzy risk of low water quality. Fuzzy multiobjective programming is used to formulate the multiobjective model. Probabilistic Global Search Laussane (PGSL), a global search algorithm developed recently, is used for solving the resulting non-linear optimization problem. The algorithm is based on the assumption that better sets of points are more likely to be found in the neighborhood of good sets of points, therefore intensifying the search in the regions that contain good solutions. Another model is developed for risk minimization, which deals with only the moments of the generated probability density functions of the water quality indicators. Suitable skewness values of water quality indicators, which lead to low fuzzy risk are identified. Results of the models are compared with the results of a deterministic fuzzy waste load allocation model (FWLAM), when methodologies are applied to the case study of Tunga–Bhadra river system in southern India, with a steady state BOD–DO model. The fractional removal levels resulting from the risk minimization model are slightly higher, but result in a significant reduction in risk of low water quality.     

Water quality monitoring in the Paul do Boquilobo Biosphere Reserve

The Paul do Boquilobo is an important wetland ecosystem classified by Unesco as a MAB Biosphere reserve also awarded Ramsar site status, representing one of the most important habitats for the resident nesting colony of Cattle Egret (Bulbucus ibis). Yet owing to its location, it suffers from human induced impacts which include industrial and domestic effluent discharges as well as agricultural land use which have negatively impacted water quality. The current study reports the results obtained from the introductory monitoring programme of surface water quality in the Nature Reserve to emphasize the detrimental impact of the anthropogenic activities in the water quality of such an important ecosystem. The study involved physicochemical and biotic variables, microbial parameters and biological indicators. Results after 3 years of monitoring bring to evidence a poor water quality further impaired by seasonal patterns. Statistical analysis of data attributed water quality variation to 3 main parameters – pH, dissolved oxygen and nitrates, indicating heavy contamination loads from both organic and agricultural sources. Seasonality plays a role in water flow and climatic conditions, where sampling sites presented variable water quality data, suggesting a depurative function of the wetland.     

改性粘土辅助沉水植物修复技术维持清水稳态的原位研究

在富营养湖泊治理实践中,修复沉水植被被认为是改善水质的长效措施,而壳聚糖改性粘土是短期快速改善水质的有效手段.本研究利用改性粘土辅助沉水植被修复,旨在探索改善水质的长效方案.2011年5-11月在太湖梅梁湾开展了四组不同处理(对照、水草、水草+粘土、粘土)围隔实验,在水草(盖度13.0%)和水草+粘土(盖度52.3%)围隔中不同程度重建了苦草群落.实验期内每3 d一次的水质监测表明,粘土处理可显著改善水质,水体总氮(TN)、总磷(TP)、正磷酸盐(PO34--P)和叶绿素a(Chl.a)含量分别比对照下降了20.7%、74.6%、31.0%和80.4%,透明度(SD)升高了90.4%;粘土辅助植被修复改善水质效果最长稳,水体TN、TP、PO34--P和Chl.a含量分别比对照下降了36.2%、64.0%、28.6%和71.1%,SD升高了76.4%;低盖度苦草群落单独处理对水质改善效果不显著.在三种处理中,粘土辅助植被修复改善底质效果最好,使间隙水的TN、TP、PO34--P、NH4+-N分别比实验前下降了15.6%、61.7%、55.8%和82.8%.本研究表明改性粘土辅助沉水植被修复可作为重富营养水体中水质改善的整合技术,但其长期生态效应仍需谨慎评估.