1990-2016年湘江干流水质变化特征及影响因素分析

基于1990-2016年湘江干流主要断面的水质监测数据,采用综合污染指数法、Spearman秩相关检验和主成分分析法对流域水环境质量演变特征进行综合评价,并结合社会经济指标识别流域主要污染源。综合污染指数结果表明湘江水环境变化趋势明显分为两个阶段,1990-1996年间为水质变好阶段,除个别值外污染指数均小于0.2,1997-2016年间水质呈恶化趋势,水质维持在Ⅲ~IV类之间;Spearman秩相关检验结果表明污染物浓度总体呈增加趋势,其中TP、COD_Mn、Cd、Pb和石油类显著上升;主成分分析结果表明流域污染物主要为NH₄⁺-N、TP和Cd,污染源为生活点源和农业面源,从上游到下游污染程度明显增大,其中湘潭断面水质污染最严重,综合得分为0.9006,道县断面相对较轻,综合得分为-0.7014,城镇化因素是影响流域水环境的主要驱动因素。研究结果可为流域水环境保护和水生态修复提供科学依据。     

土地利用/景观格局对水环境质量的影响

土地利用/景观格局已成为影响中国水环境质量的重要因素,但目前仍然欠缺土地利用/景观格局和水环境质量之间复杂关系的深入研究。以湟水流域小峡桥断面上游为例,兼顾水环境承载力与人为活动所产生的压力,建立土地利用/景观格局对水环境质量影响的结构方程模型,计算不同土地利用/景观格局指标对水环境质量的贡献率。研究表明:点源污染是湟水流域水环境质量恶化的主要因素,其贡献率最大(37.3%);而土地利用/景观格局的4个指标(不透水面面积占比、建设用地中绿地面积占比、湿地连通性和湿地聚集度)对水环境质量的贡献率相对较大,分别为9.14%、 7.91%、 7.44%和6.96%。加大点源污染控制力度、增强湿地连通性与聚集度、增大建设用地中绿地面积并减少不透水面面积是改善湟水流域小峡桥断面上游水环境质量的有效措施。     

Characteristics of the main inorganic nitrogen accumulation in surface water and groundwater of wetland succession zones

Based on the observation of a complete hydrological year from June 2014 to May 2015, the temporal and spatial variations of the main inorganic nitrogen(MIN, referring to NO_3~--N, NO_2~--N, NH_4~+-N) in surface water and groundwater of the Li River and the Yuan River wetland succession zones are analyzed. The Li River and the Yuan River are located in agricultural and non-agricultural areas, and this study focus on the influence of surface water level and groundwater depth and precipitation on nitrogen pollution. The results show that NO_3~-N in surface water accounts for 70%-90% of MIN, but it does not exceed the limit of national drinking water surface water standard. Groundwater is seriously polluted by H_4~+-N. Based on the groundwater quality standard of H_4~+-N, the groundwater quality in the Li River exceeds Class III water standard throughout the year, and the exceeding months' proportion of Yuan River reaches 58.3%. Compared with the Yuan River, MIN in groundwater of the Li River shows significant temporal and spatial variations owing to the influence of agricultural fertilization. The correlation between the concentrations of MIN and surface water level is poor, while the fitting effect of quadratic correlation between H_4~+-N concentration and groundwater depth is the best(R~2=0.9384), NO_3~-N is the next(R~2=0.5128), NO_2~--N is the worst(R~2=0.2798). The equation of meteoric water line is δD =7.83δ~(18) O+12.21, indicating that both surface water and groundwater come from atmospheric precipitation. Surface infiltration is the main cause of groundwater H_4~+-N pollution. Rainfall infiltration in non-fertilization seasons reduces groundwater nitrogen pollution, while rainfall leaching farming and fertilization aggravate groundwater nitrogen pollution.     

Characteristics of the main inorganic nitrogen accumulation in surface water and groundwater of wetland succession zones

Based on the observation of a complete hydrological year from June 2014 to May 2015, the temporal and spatial variations of the main inorganic nitrogen (MIN, referring to NO3--N, NO2--N, NH4+-N) in surface water and groundwater of the Li River and the Yuan River wetland succession zones are analyzed. The Li River and the Yuan River are located in agricultural and non-agricultural areas, and this study focus on the influence of surface water level and groundwater depth and precipitation on nitrogen pollution. The results show that NO3--N in surface water accounts for 70%-90% of MIN, but it does not exceed the limit of national drinking water surface water standard. Groundwater is seriously polluted by NH4+-N. Based on the groundwater quality standard of NH4+-N, the groundwater quality in the Li River exceeds Class III water standard throughout the year, and the exceeding months’ proportion of Yuan River reaches 58.3%. Compared with the Yuan River, MIN in groundwater of the Li River shows significant temporal and spatial variations owing to the influence of agricultural fertilization. The correlation between the concentrations of MIN and surface water level is poor, while the fitting effect of quadratic correlation between NH4+-N concentration and groundwater depth is the best (R2=0.9384), NO3--N is the next (R2=0.5128), NO2--N is the worst (R2=0.2798). The equation of meteoric water line is δD =7.83δ18O+12.21, indicating that both surface water and groundwater come from atmospheric precipitation. Surface infiltration is the main cause of groundwater NH4+-N pollution. Rainfall infiltration in non-fertilization seasons reduces groundwater nitrogen pollution, while rainfall leaching farming and fertilization aggravate groundwater nitrogen pollution.     

Water quality changes in the Elbe River basin,Czech Republic,in the context of the post-socialist economic transition

This paper analyses the temporal dynamics and spatial trends in water quality changes in the Elbe River basin in the context of the post-socialist economic transition of the Czech Republic (Czechia). During the 1990s, the Czech portion of the Elbe River Basin underwent significant changes in the quality of surface waters. After a long period of massive discharges of pollution, which reached a peak at the end of the 1980s, a reduction in effluent from industrial and municipal sources led to a substantial decrease in the pollution of the Elbe River and its principal tributaries. The scope and speed of such water quality changes was unprecedented in Czechia as well as throughout Europe. The classification of the spatial distribution of water quality trends revealed that the majority of streams in the Czech Elbe River basin displayed improvement of surface water quality. However, the decrease in pollution levels was spatially concentrated mainly in the Elbe River and its main tributaries. Many of the peripheral streams are, on the contrary, experiencing deteriorating water quality, even in regions where water quality improved in the early 1990s because of a decline in local economic activity associated with political changes in the former Eastern Block countries. Further improvements in water quality are thus dependent on measures adopted across the entire river basin, including the numerous minor streams. The current economic revival in a number of regions where decreases in water pollution were not based on systematic pollution reduction measures, but only on the decline of industrial or agricultural production, may result in a return to deteriorating water quality, primarily in the outer regions of the catchment.     

铜陵矿区主要河流水质分析与污染评价

铜陵矿区是长江下游重要的铜铁资源基地,也是典型的含硫多金属矿区,矿山酸性废水是矿业开发活动不可避免的环境问题,对地表水体有很大影响。本文以铜陵矿区主要河流为研究对象,通过野外调查采样和室内测试分析,从常规理化性质、矿山酸性废水和重金属元素三方面分析了的水质现状,采用单因子指数和内梅罗水质指数法进行了污染评价。结果表明:(1)矿区河流污染成分以有机污染和矿山酸性废水污染为主,其次是重金属污染。(2)在检测的46个河段中, 按综合污染指数大小分级,共计有93.48%的河段受到不同程度的污染,其中,水质严重污染的河段占 4.35%,水质重污染的河段占13.04%,水质污染的河段占 65.22%,水质轻污染的河段占10.87%;共计有6.52%的河段水质较好,均为清洁状态。(3)3条河流按污染程度大小依次为新桥河>顺安河>红星河,除顺安河外,其他均受到了矿山酸性废水污染。今后应重点关注矿山酸性废水的污染机理与风险评估,加强矿区水环境保护与恢复治理工作。     

漓江流域表层土壤水分物理性质空间异质性

为了解漓江流域土壤水分空间变化特征及其影响因素,基于2'经纬网格,采用地统计学方法对该流域表层（0~10 cm）土壤水分物理性质的空间变异进行分析。结果表明:从空间结构比上,漓江流域表层土壤含水量、容重、最大和最小持水量均具有高度的空间自相关性（各指标空间结构比均大于0.87）,且其空间分布趋势基本一致,由流域上游向中下游逐渐变化。土地利用对流域表层土壤水分物理性质及其空间变异具有显著影响。受时间尺度和土地利用类型等因素的影响,漓江流域表层土壤含水量相比其他土壤水分物理性质,其空间异质性由随机引起的空间变异增加,空间自相关减小,为0.87;而土壤容重最大,为0.92。相关结果对于漓江流域土壤水分动态模拟与预测研究具有一定参考价值。     

汉江流域硫铁矿区厚子河支流水质评价研究

为查明厚子河不同区域河水受硫铁矿污染的程度,在厚子河支流4个典型河流断面采集水样,开展水质全分析测试,并采用单因子评价法和综合水质标识指数法进行评价分析。研究结果表明: (1)运用单因子评价法对硫铁矿区厚子河水质评价的结果无差异,均为劣Ⅴ类水; 而运用综合水质标识指数法的评价结果显示,距离硫铁矿开采区由近及远的4个断面HZ001、HZ002、HZ003、HZ004的综合水质标识指数逐渐下降,水质类别分别为劣Ⅴ类且黑臭、劣Ⅴ类但不黑臭、Ⅳ类、Ⅲ类,符合现场调查的实际情况,能够反映距离污染源越远时河水水质趋好的总体态势; (2)综合水质标识指数法不仅可以客观反映同一河流各个断面所处的综合水质类别、同一水质类别中受污染的不同程度以及与水环境功能区类别的比较结果,而且能够实现对劣V类水质污染程度的精细划分,相较于单因子评价法更加客观、科学、全面,适用于矿山开采等重污染区域河流断面水质污染情况的研判。     

汉江流域硫铁矿区厚子河支流水质评价研究

为查明厚子河不同区域河水受硫铁矿污染的程度,在厚子河支流4个典型河流断面采集水样,开展水质全分析测试,并采用单因子评价法和综合水质标识指数法进行评价分析。研究结果表明: (1)运用单因子评价法对硫铁矿区厚子河水质评价的结果无差异,均为劣Ⅴ类水; 而运用综合水质标识指数法的评价结果显示,距离硫铁矿开采区由近及远的4个断面HZ001、HZ002、HZ003、HZ004的综合水质标识指数逐渐下降,水质类别分别为劣Ⅴ类且黑臭、劣Ⅴ类但不黑臭、Ⅳ类、Ⅲ类,符合现场调查的实际情况,能够反映距离污染源越远时河水水质趋好的总体态势; (2)综合水质标识指数法不仅可以客观反映同一河流各个断面所处的综合水质类别、同一水质类别中受污染的不同程度以及与水环境功能区类别的比较结果,而且能够实现对劣V类水质污染程度的精细划分,相较于单因子评价法更加客观、科学、全面,适用于矿山开采等重污染区域河流断面水质污染情况的研判。     

黑龙江流域水体和沉积物重金属的生态风险研究

中国东北黑龙江流域作为重工业基地和商品粮基地,水体、沉积物和土壤的重金属污染非常值得关注。作者采集了黑龙江流域从上游干旱区到下游三江平原的河水、湖水、地下水和河床沉积物样品,分析重金属元素含量,运用不同指标评估了流域的水资源安全和沉积物的污染风险程度。研究结果显示,在黑龙江流域上游干旱区,部分地表水和地下水的As含量超过了中国生活饮用水卫生标准,最多接近7倍,上游地区居民的用水安全需要引起有关部门的关注。通过内梅罗指数法（P 综合）和潜在生态危害指数（RI ）的综合评估表明,黑龙江流域沉积物的总体生态风险较低。单个重金属元素中,Cd在大部分流域存在中等生态风险,有3个沉积物样品展现出较高生态风险。Cd作为危害中国耕地土壤和人类健康的主要重金属元素,在黑龙江流域同样也需要予以重点关注。     

Study on the gravity center evolution of air pollution in Yangtze River Delta of China

With the rapid development of China’s economy, air pollution is becoming extremely serious. The spatial–temporal evolution of air pollution is conducive to the management of air pollution. The paper is proceeded into three steps. Firstly, based on the generalization principal component analysis method, the comprehensive air pollution evaluation index is established. Then, the gravity center model is utilized to explore the spatial–temporal evolution of air pollution in Yangtze River Delta from January 2014 to December 2016. Finally, the contribution decomposition method is utilized to explore the contribution to gravity center evolution. The main results are as follows: (1) The air pollution have obvious seasonal and regional differences in Yangtze River Delta. (2) The gravity center of air pollution continues to westward after 2014 with the characteristic of the north–south circular movement. (3) Hefei City and Yangzhou City have huge impact on the gravity center evolution of air pollution. The conclusions could be helpful for Chinese government to control the air pollution in Yangtze River Delta.     

Integrated assessment of nonpoint source pollution of a drinking water reservoir in a typical acid rain region

Nonpoint source pollution generated by agricultural production and city construction has been studied for decades, but very few researches have been conducted on the regional assessment of nonpoint source pollution in the acid rain regions, particularly relating to the control of pollutant in the drinking water source areas. In this study, an integrated framework was applied to estimate nitrogen and phosphorous load in a typical acid rain influenced reservoir, China. The method comprised three separate steps: (1) a watershed model—soil and water assessment tools—was used to estimate nitrogen and phosphorous load from the upper stream watershed; (2) collection of acid rain samples, together with a GIS-based calculation to estimate the atmospheric deposition flux; (3) introduction of a simple export coefficient method. The case study indicated atmospheric deposition accounted for 56.75 % of total nitrogen load during the year, with the highest level of deposition load taking place during the wet season. Maximum phosphorous (93.37 %) was linked to the upstream runoff, originating from the upper watershed. Further analysis by watershed model and export coefficient method indicated forest exported most total nitrogen (27.72 %) and total phosphorous (58.78 %) in the upstream watershed. Results indicated that in the region influenced by acid rain, the nitrogen management should encompass the management of land use practices and the control of acid rain in catchments feeding into drinking water storage areas. It could be inferred that NOX emissions might cause both globe warming and eutrophication in the drinking water sources. This paper could provide a basis for water quality management in such regions.     

Distribution of trace elements in waters and sediments of the Seversky Donets transboundary watershed (Kharkiv region,Eastern Ukraine)

This paper reports on the aquatic chemistry of trace elements in terms of spatial and temporal distribution, but also pollution sources in the transboundary watershed of the Seversky Donets River (Ukraine/Russia). Bed sediments and filtered water were collected from the Udy and Lopan Rivers at sites from the river source in the Belgorod region (Russia) to rural and urban areas in the Kharkiv region (Ukraine) in May and August 2009. Priority trace elements (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn), an urban tracer (Ag) and additional metals (Co, Mo, V) and Th were measured in stream water and sediments. The low levels and variability of Th-normalized concentrations indicated the absence of geochemical anomalies in the upstream part of the rivers and suggested that these data represent a regional baseline for trace elements in bed sediments. In contrast, water and sediments within the city of Kharkiv were contaminated by Ag, Pb, Cd, Cu, Cr and Zn, which are mainly attributed to municipal wastewater inputs and urban run-off. Results of the environmental quality assessment showed that element concentrations in the sediments can be considered as potentially toxic to aquatic organisms in sites downstream of the wastewater discharges.     

江油市青莲镇规划应急水源地分析与评价

涪江作为江油市重要饮用水来源,在遭受上游水污染发生后,需要及时更换应急水源地供水,结合流域特点,选址青莲镇作为江油市应急水源地。通过调查研究青莲镇地下水资源量,全面研究了该地区地下水补给量、储存量和消耗量,并采集水源地水样进行实验分析,获取水源地水化学特征,研究结果显示青莲镇地下水水量、水质满足江油市应急水源地要求,最后利用层次分析法对江油市应急水源地进行了适宜性评价。     

邕江南宁段水质现状及防治对策探讨

根据影响南宁地区最大的河流——邕江近年污染物排放状况和3个水质控制断面的氨氮、生化需氧量、高锰酸盐指数和石油类等监测资料进行初步分析,本文主要从水质现状、主要污染因子和污染原因考察了邕江的水环境状况。结果显示,邕江水质总体上属于II~III类水质,但部分断面有恶化趋势,主要是溶解氧和氨氮超标;主要污染物为石油类、氨氮、高锰酸盐指数和五日生化需氧量,这表明邕江的污染类型属于典型的有机型污染。同时,也指出了邕江水质污染特征和主要存在的问题,并根据南宁市水污染的成因和水污染因素的分析,提出了保护和改善邕江水质的建议。     

长江上游沱江流域地表水环境质量时空变化特征

沱江是长江流域上游最重要的支流之一,为了明晰沱江流域水质时空变化特征和防治重点,根据2010—2017年沱江流域36个监测断面水质监测数据,采用单因子评价法和秩相关系数法,从年份、月份、季度和水期4个时间段进行了分析.结果表明:沱江流域水质状况总体上污染较重,但有向好趋势,总磷(TP)为首要污染物,流域断面达标率呈先上升后下降复上升的趋势;水质指标浓度年内变化显著,水质指标浓度丰水期达到最小值,枯水期达到最大值;沱江干流监测断面水质类别好于支流;TP和氨氮(NH₃-N)浓度空间变异性较弱,化学需氧量(COD)和生化需氧量(BOD₅)浓度则存在较强空间变异性.虽然沱江流域水质有变好趋势,但沱江流域面临的污染问题依然严峻,今后要高度重视污染源治理,尤其是TP的防治工作.      

基于分布式水文模型的长江上游水资源时空变异性分析

本文首先分析了长江流域内154个气象站降水量和26个干支流水文站流量在1950～2000年期间的变化趋势。为定量分析长江上游地区降水量时空变化对水资源量的影响,构建了基于物理机理的分布式水文模型,模拟再现了天然河道条件下的水文过程。有别于传统的河道径流性水资源评价方法,本文尝试用径流深的空间变化来探讨水资源分布及演变态势。并以渠江罗渡溪水文站为个案,剖析了90年代秋季流量大幅减少的主要缘由。结果表明:受降水在时空分布上存在变异的影响,长江上游局部地区夏季径流深比率呈增加趋势,而秋季则相反;导致嘉陵江渠江水系秋季流量减少的主要原因是降雨,其次才是人为因素。     

Simulation of spatial and temporal distribution on dissolved non-point source nitrogen and phosphorus load in Jialing River Watershed,China

Jialing River, which covers a basin area of 160,000 km² and a length of 1,280 km, is the largest tributary of the catchment area in Three Gorges Reservoir Area, China. In recent years, water quality in the reservoir area section of Jialing River has been degraded due to land use and the rural residential area induced by non-point source pollution. Therefore, the semi-distributed land-use runoff process (SLURP) hydrological model has been introduced and used to simulate the integrated hydrological cycle of the Jialing River Watershed (JRW). A coupling watershed model between the SLURP hydrological model and dissolved non-point source pollution model has been proposed in an attempt to evaluate the potential dissolved non-point source pollution load; it enhances the simulation precision of runoff and pollution load which are both based on the same division of land use types in the watershed. The proposed model has been applied in JRW to simulate the temporal and spatial distribution of the dissolved total nitrogen (DTN) and dissolved total phosphorus (DTP) pollution load for the period 1990–2007. It is shown that both the temporal and spatial distribution of DTN and DTP load are positively correlated to annual rainfall height. Land use is the key factor controlling the distribution of DTN and DTP load. The source compositions of DTN and DTP are different, where average DTN pollution load in descending order is land use 67.2%, livestock and poultry breeding 30.5%, and rural settlements 2.2%; and for DTP, livestock and poultry breeding is 50%, land use 48.8%, and rural settlements 1.2%. The contribution rates of DTN and DTP load in each sub-basin indicate the sensitivity of the results to the temporal and spatial distribution of different pollution sources. These data were of great significance for the prediction and estimation of the future changing trends of dissolved non-point source pollution load carried by rainfall runoff in the JRW and for studies of their transport and influence in the Three Gorges Reservoir.     

Relationship between the variation of water quality in rivers and the characteristics of watershed at Miyun,Beijing, China

Based on the characteristics of land use and drainage network of the upper watershed of the Miyun Res-ervoir, Beijing, 26 monitoring and sampling sites were selected in different sub-catchments. Temporal and spatial variations in nutrient loss were dealt with in this paper in terms of the monitoring data on the water quality of the main tributaries flowing into the Miyun Reservoir. In combination with the monitoring data on water quality, the impacts of watershed characteristics including land-use type, landscape pattern, and drainage density were assessed, The concentrations of nutrients in the rainy season are higher than those in other seasons, and the concentrations of NO3--N are linearly related to those of total N which is the main form of nitrogen present in the fiver water. The concentrations of nitrogen become higher toward the reservoir along the main rivers. The seasonal variation of ni-trogen in the watershed affected by intensive human activities is very obvious; in the watershed with steady or low water flow, the seasonal variation of nitrogen is less obvious. Forest land and grassland can trap and filter nitrogen effectively. Land-use pattern also has important impacts on the loss of nitrogen. The concentrations of nitrogen and phosphorus in the water bodies show great temporal and spatial variations. On a temporal scale, the concentrations of TN and TP in the rainy reason are higher than those in other seasons. On a spatial scale, the concentrations of TN and NO3--N in the Qingshui River and Chaohe River are highest all the time. The spatial variation of TP is distinct, being obvious at sampling sites near villages. The form of nitrogen and phosphorus loss varies in different hydrological seasons. Dissolved nitrogen and phosphorus are the main forms in streams in non-rainy seasons, the dissolved nitro-gen and total nitrogen decrease in percentage in the rainy season. Particulate nitrogen and phosphorus are the main forms in some rivers. The concentrations of TN and NO3--N from orchards and villages are high whereas those from forest land are lowest. Land-use pattern has impacts on TN and NO3--N losses, at the sampling sites near the source landscape, the concentrations are higher than those at the sampling sites near the sink landscape. Water quality of the rivers which flow into the Miyuan Reservior is influenced by the composition of adjacent soils.     

数字黑河的思考与实践4:流域观测系统

数字化的流域观测系统是数字流域的重要组成部分.①首先介绍了水循环卫星遥感和地面观测的最新进展,以及航空遥感在流域观测中的重要作用.②介绍了对于流域观测系统的构想.认为流域观测系统应兼顾陆面过程、水文、生态观测的不同空间尺度和时间尺度,监测与控制试验并重,地面与遥感配合,重视采样设计,重视新兴观测手段,与信息系统扣模型高度集成,科学目标导向,模型需求驱动.③黑河流域观测系统由位于流域上中下游不同景观带的野外研究站、综合观测试验以及气象水文业务化观测网络组成,在流域内先后开展了HEIFE实验、金塔试验和黑河综合遥感联合试验.④介绍了对于流域观测系统的进一步构想:增强遥感观测能力是关键,集成遥感、地面观测和模型模拟才能更好地定量估计水循环,流域观测系统应和信息系统、综合模型等共同构成流域科学研究的信息基础设施,更好地为流域科学服务.