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1.
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in surface sediment samples from Taihu Lake--an important water supply of the Yangtze River Delta, China--were investigated in the present study. Concentrations of PCDD/Fs ranged from 0.91 to 4.8 pg TEQ g(-1) dw (mean: 2.9 pg TEQ g(-1) dw, TEQ: Toxic Equivalent), which were all higher than the threshold effect level established by interim sediment quality guidelines in Canada (0.85 pg TEQ g(-1) dw). The levels of PBDD/Fs ranged from 0.16 to 1.6 pg TEQ g(-1) dw (mean: 0.52 pg TEQ g(-1) dw) and accounted for 5-33% (mean: 14%) of the total PCDD/Fs and PBDD/Fs TEQ. Comparatively, the abundance of sedimentary PCDD/Fs in the three regions (Meiliang Bay, Gonghu Bay, and Xukou Bay) showed a decreasing trend from the inflow region to the outflow region, while no significant difference was observed among their 2,3,7,8-PBDD/Fs levels, which suggested that the sources of PCDD/Fs and PBDD/Fs differed in this area. Principal component analysis suggested that the historical production/usage of pentachlorophenol and sodium pentachlorophenate was the dominant source of PCDD/Fs in the sediment of these regions. Although the specific sources of PBDD/Fs in the sediment of Taihu Lake were unclear, it was suspected to be due to atmospheric deposition; however, an additional study is needed to confirm this.  相似文献   

2.
Most of freshwater bodies all over the world are becoming polluted, thus decreasing the portability of the water. In India religious practices have deep relationship with water bodies. They also patronized religious practices and constructed numerous relatively small water bodies along with temples throughout the country. Today, with the rapid pace of urban development, most of these water bodies have become sinks for waste discharge, resulting in deterioration of their water quality. Upper Lake of Bhopal, constructed in the eleventh century, is typical example of urban water bodies and a major source of potable water for the people of Bhopal. Till the middle of the last century, the water of Upper Lake did not require any treatment before supply for drinking purposes. Idol worship is common in India. Idols are usually made up of wood, bamboo, straw, jute ropes, clay, and plaster of Paris and are painted with bright synthetic colors, which often contain heavy metals. Other materials, such as straw, jute ropes, flowers, leaves and germinated grains cause short-term deterioration of water quality on their decay, while heavy metals in the paints pose health hazards in the long-run. Religious issues are extremely sensitive and hence it was felt necessary to use the regard that the citizens had for the lake to build a consensus in support of change. The Bhoj Wetland Project was implemented with the aid of Japanese Bank of International Cooperation (JBIC) to take action for preserving the Upper Lake of Bhopal (called Bhoj Wetlands). Our study is highlighted to water quality parameters like turbidity, total hardness, DO (Dissolved oxygen), BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand) and heavy metals in the year 1999 and 2005 i.e. before implementation of project and completion of project.  相似文献   

3.
Composite Water Quality Identification Index (CWQII) and multivariate statistical techniques were used to investigate the temporal and spatial variations of water quality in Honghu Lake. The aims are to explore the characteristics of water quality trends in annual, monthly, and site spatial distribution and to identify the main pollution factors. The results showed that the values of CWQII increased from 2.0 to 4.0 from the years 2001 to 2005, then decreased from 2006 and kept a balance between 2.0 and 3.0 from 2006 to 2011, indicating that the water quality of Honghu Lake deteriorated from 2001 to 2005 and has gradually improved since 2006, which were likely achieved after water protection measurements taken since 2004. The monthly change rules of water quality were influenced by a superposition of natural processes and human activities. In samples numbered 1–9 from upstream to downstream, the maximum values of CWQII often occurred in sample site 9 while the minimum ones often occurred in sample site 2, indicating that the water quality near the upstream tributary was the poorest and that in the core zone was the best. Incoming water from the trunk canal of the Sihu area upstream was the largest pollution source. The sensitive pollution nutrients were mainly caused by the total nitrogen, followed by the total phosphorus.  相似文献   

4.
This article presents the geochemical characteristics and physicochemical properties of water and sediment from twelve semi-permanent, dryland pools in the upper Leichhardt River catchment, north-west Queensland, Australia. The pools were examined to better understand the quality of sediments and temporary waters in a dryland system with a well-established metal contamination problem. Water and sediment sampling was conducted at the beginning of the hydroperiod in May and September 2007. Water samples were analyzed for major solute compositions (Ca, Na, K, Mg, Cl, SO(4), HCO(3)) and water-soluble (operationally defined as the <0.45 μm fraction) metals (Cd, Cu, Pb, Zn). Sediment samples were analyzed for total extractable and bioaccessible metals (As, Cd, Cu, Pb, Zn), elemental composition and grain morphology. At the time of sampling a number of pools contained water and sediment with elevated concentrations, compared to Australian regulatory guidelines, of Cu (maximum: water 28 μg L(-1); sediment 770 mg kg(-1)), Pb (maximum: water 3.4 μg L(-1); sediment 630 mg kg(-1)) and Zn (maximum: water 150 μg L(-1); sediment 780 mg kg(-1)). Concentrations of Cd and As in pools were relatively low and generally within Australian regulatory guideline values. Localized factors, such as the interaction of waters with anthropogenic contaminants from modern and historic mine wastes (i.e. residual smelter and slag materials), exert influence on the quality of pool waters. Although the pools of the upper Leichhardt River catchment are contaminated, they do not appear to be the primary repository of water and sediment associated metals when compared to materials in the remainder channel and floodplain. Nevertheless, a precautionary approach should be adopted to mitigating human exposure to contaminated environments, which might include the installation of appropriate warning signs by local health and environmental authorities.  相似文献   

5.
The distribution of perfluorinated compounds (PFCs) in Baiyangdian Lake, China, was determined in this study. Perfluorooctanoic acid (PFOA) was the dominant PFC in lake water (1.70-73.5 ng L(-1), median 9.72 ng L(-1)), while perfluorooctane sulfonate (PFOS) was the dominant PFC in sediments (0.06-0.64 ng g(-1) dry wt, median 0.19 ng g(-1) dry wt) and in aquatic animals (0.57-13.7 ng g(-1) wet wt, median 2.56 ng g(-1) wet wt). Significant differences in PFC levels were observed among various aquatic animals. We also determined, for the first time, the PFC levels in floating plants, including Ceratophyllum demersum L., Hydrocharis dubia (Bl.) Backer and Salvinia natans (L.), and we found that PFOA and PFNA were the dominant PFCs in these plants. Furthermore, floating plants were observed to have different composition profiles compared to aquatic animals. Geographical differences in PFC levels were also observed, with higher PFC levels in samples from the north part of Baiyangdian Lake than those in the south. The differences in human and industrial activities in different parts of the lake and the discharged wastewater from the Fuhe River may be the major contributors for these geographical differences.  相似文献   

6.
Water quality assessment of Lake Pandu Bodhan, Andhra Pradesh State, India   总被引:1,自引:0,他引:1  
A systematic investigation of variations in some nutrient levels at Pandu Lake from August 2002 to July 2004 was carried out. The untreated domestic wastes from various parts of Bodhan town are directly discharged into Pandu Lake leading to gross pollution. Therefore present investigation was under taken to assess the magnitude of sewage pollution by monitoring key water quality parameters dissolved oxygen, biological oxygen demand, alkalinity, calcium, nitrates and phosphates etc. Monthly water samples were collected from three different sampling stations. Low Dissolved oxygen and high biological oxygen demand, elevated Nitrates and Phosphates levels were found, which gives the information about conversion of this water body from oligotrophic to eutrophic nature. Phosphates were found to be in the range of 0.9 to 4.0 mg/L. Nitrates were found to be higher in Pandu Lake and their number is more in summer, and suitable explanation was given. Nitrates were found to be in range between 24.8mg/L to 71.2mg/L. Data on various chemical characteristics vary at different sites in different months in Pandu Lake. Some of the characteristics like Dissolved Oxygen, Biological Oxygen Demand, Nitrates, Phosphates and nutrient loading are contributing to eutrophication process in this lake and the lake seems to be eutrophic through out the year.  相似文献   

7.
The pollution sources around the Dapeng bay and the current water quality of the bay are presented. Two-dimensional mathematical models for modelling the tidal flow and pollutant concentration fields have been developed and used to predict the water quality impact generated by coastal economic development of the area. Water quality planning for the bay is conducted and some managerial measures for environmental protection are put forward. The results show that at present there is minimal pollution, and the water quality is good. If the region around the bay is to be developed as proposed, it would have minor impact on the marine water quality. The aim is to have the water quality higher than that of Class II standard in National Marine Water Quality Standard of China (NMWQSC). In order to maintain the present condition of the bay, the ecological equilibrium around the bay must be preserved.  相似文献   

8.
9.
Environmental Monitoring and Assessment - A good quality drinking water is essential for human survival. However, a large percentage of the populations in most developing countries (Nigeria...  相似文献   

10.
Although satellite radar altimetry was developed and optimized for open oceans, it has been used to monitor variations in the level of inland water-bodies such as lakes and rivers. Here, for the first time, we have further used the altimetry-derived variation of water level for estimating the fluctuation of water storage as an addition to the present in situ water storage estimation systems to be used in remote areas and in emergency situation such as in the events flooding monitoring and for studying the effect of climate change. Lake Dongting, the second largest lake in China, influenced frequently by flooding, was, therefore, chosen to demonstrate the potential of the technique. By using the concept of an “assumed reference point”, we converted Topex/Poseidon satellite altimetry data on water level variations in Lake Dongting to “water level” data. The “water level” time-series data and in situ water storage were used to establish a rating curve. From the rating curve, we converted data on “water level” derived from seven years (1993–1999) of Topex/Poseidon data to actual water storage in Lake Dongting. The result reveals that the seasonal and annual fluctuations of water storage occurred during the 1990s with a more frequent flooding at the late 1990s' especially the flooding in whole catchment level in 1998 and 1999. The study supports the usefulness of satellite altimetry for dense and continuous monitoring of the temporal variations in water dynamic in moderate to large lakes.  相似文献   

11.
洪湖水质空间特异性及主导因子分析   总被引:8,自引:6,他引:2  
运用聚类分析和主成分分析方法对洪湖湿地12个采样点的理化特性进行分析。聚类分析表明,根据各采样点水质组分的相似性将洪湖大致分为3个空间区域,各空间区域正好分属于核心区、实验区、河口区,各区域间特征差异显著。对各区域水质的主成分分析表明,洪湖不同空间区域水质信息差异很大。第1组核心区主要体现富营养化信息;第2组实验区主要体现总氮、氧化还原电位、浊度信息;第3组河口区主要体现溶解氧及亚硝酸盐氮等污染物信息。揭示了洪湖水质现状及其成因,为洪湖水资源合理利用及生态保护提供基础数据。同时,运用地统计学方法为生态环境研究提供新的思路与方法。  相似文献   

12.
Coastal aquaculture is faced with extreme variation in water quality. The Deeba Triangle on Lake Manzala is the largest marine coastal aquaculture-producing area on the Egyptian Mediterranean. Samples from 16 ponds were taken during four seasons (2014–2015), to investigate the variation of 12 water quality parameters at that region. We tested the hypothesis that there is no spatial or temporal variation in water quality of the fish ponds. Fish ponds were statistically clustered into three groups (p?=?0.0005) coincident with their geographical location. Hypersaline and transparent waters characterized the western ponds; higher dissolved oxygen and higher nutrients characterized the central region. These spatial differences were principally due to variations in salinity and nutrients of the water sources used for irrigation of the ponds and to differences in the aeration management styles. Strong seasonality was seen in water temperature (following air temperature), nutrients, and turbidity (following the seasonal cycles of various water sources from the Lake Manzala and the seasonality of the petrochemical plants effluents close to these ponds). We conclude that municipal effluents significantly affected, spatially and temporally, the quality of the irrigation water used for coastal aquaculture purposes, which consequently might affect fish yield.  相似文献   

13.
Suspended sediment and nutrient loadings from agricultural watersheds have lead to habitat degradation in Lake Takkobu. To examine their relationships with land-use activities, we monitored sediment, nutrient and water discharges into the lake for a 1-year sampling period. The Takkobu River contributed the largest portion of the annual water discharge into the lake, compared with the other tributaries. During dry conditions, lake water flowed into the Kushiro River, and conversely during flooding, Kushiro River water flowed into the lake. Inflows from the Kushiro River had a high proportion of inorganic matter, with high concentrations of total nitrogen and total phosphorus, attributed to agricultural land-use development and stream channelization practiced since the 1960s in the Kushiro Mire. Nutrient loadings from these two rivers were significantly higher during flooding than in dry conditions. However, there was no clear correlation between river discharge and nutrient concentrations. Since land-use activities in the Kushiro River and Takkobu River watersheds were concentrated near rivers, nutrients easily entered the drainage system under low flow conditions. In contrast, water discharged from small, forest-dominated watersheds contained a low proportion of inorganic matter, and low nutrient concentrations. The suspended sediment delivered to the lake during the sample period was estimated as approximately 607 tons, while the total nitrogen and total phosphorus inflows were about 10,466 and 1,433 kg, respectively. Suspended sediment input into the lake was 65%, and total nitrogen and total phosphorus were 40% and 48%, respectively, being delivered by the Kushiro River.  相似文献   

14.
Water quality information of Beijiang River, a tributary of Pearl River in Guangdong, China, was analyzed to provide an overview of the hydrochemical functioning of a major agricultural/rural area and an industrial/urban area. Eighteen water quality parameters were surveyed at 13 sites from 2005 to 2006 on a monthly basis. A bivariate correlation analysis was carried out to evaluate the regional correlations of the water quality parameters, while the principal component analysis (PCA) technique was used to extract the most influential variables for regional variations of river water quality. Six principal components were extracted in PCA which explained more than 78% and 84% of the total variance for agricultural/rural and industrial/urban areas, respectively. Physicochemical factor, organic pollution, sewage pollution, geogenic factor, agricultural nonpoint source pollution, and accumulated pesticide usage were identified as potential pollution sources for agricultural/rural area, whereas industrial wastewaters pollution, mineral pollution, geogenic factor, urban sewage pollution, chemical industrial pollution, and water traffic pollution were the latent pollution sources for industrial/urban area. A multivariate linear regression of absolute principal component scores (MLR-APCS) technique was used to estimate contributions of all identified pollution sources to each water quality parameter. High coefficients of determination of the regression equations suggested that the MLR-APCS model was applicable for estimation of sources of most water quality parameters in the Beijiang River Basin.  相似文献   

15.
水质判别是一个多参数多级别的模糊概念,基础的模糊综合评价法存在局限性,对基础模糊数学法中隶属度函数及最大隶属度原则进行改进,建立一种改进的模糊综合评价法。以太湖流域水质判别为实例验证了此方法比传统的方法更有效,且适合在太湖流域应用。  相似文献   

16.
基于调查监测数据和历史数据,分析兴凯湖中国区域水质及污染现状。结果表明,兴凯湖为Ⅳ类水质,水质状况为轻度污染,处于轻度富营养化状态。主要污染指标为总磷,浓度呈逐年升高的趋势。分析其原因,穆棱河分洪水是兴凯湖地面水的主要来源,这部分水质远较其他入湖河流水质差,因此穆棱河湖北闸在洪水期的泄洪水是兴凯湖的一个主要污染源。  相似文献   

17.
In the past 30?years, the Lis river basin has been subjected to constant ecological disasters mainly due to piggery untreated wastewater discharges. The aim of this study was to evaluate the effect of existing domestic, agricultural, and industrial activities on the water quality, and to propose a watershed plan to protect and manage surface water resources within the Lis river basin. For this purpose, 16 monitoring stations have been strategically selected along the Lis river stretch and its main tributaries to evaluate the water quality in six different sampling periods (2003–2006). All samples were characterized in terms of organic material, nutrients, chlorophyll, and pathogenic bacteria. Generally, the Lis river presents poor water quality, according to environmental quality standards for surface water, principally in terms of dissolved oxygen, biochemical oxygen demand, total nitrogen, and fecal coliform, which can be associated mainly with the contamination source from pig-breeding farms.  相似文献   

18.
Water Quality Changes in Chini Lake, Pahang, West Malaysia   总被引:1,自引:0,他引:1  
A study of the water quality changes of Chini Lake was conducted for 12 months, which began in May 2004 and ended in April 2005. Fifteen sampling stations were selected representing the open water body in the lake. A total of 14 water quality parameters were measured and Malaysian Department of Environment Water Quality Index (DOE-WQI) was calculated and classified according to the Interim National Water Quality Standard, Malaysia (INWQS). The physical and chemical variables were temperature, dissolved oxygen (DO), conductivity, pH, total dissolved solid (TDS), turbidity, chlorophyll-a, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS), ammonia-N, nitrate, phosphate and sulphate. Results show that base on Malaysian WQI, the water in Chini Lake is classified as class II, which is suitable for recreational activities and allows body contact. With respect to the Interim National Water Quality Standard (INWQS), temperature was within the normal range, conductivity, TSS, nitrate, sulphate and TDS are categorized under class I. Parameters for DO, pH, turbidity, BOD, COD and ammonia-N are categorized under class II. Comparison with eutrophic status indicates that chlorophyll-a concentration in the lake was in mesotrophic condition. In general water quality in Chini Lake varied temporally and spatially, and the most affected water quality parameters were TSS, turbidity, chlorophyll-a, sulphate, DO, ammonia-N, pH and conductivity.  相似文献   

19.
The study was carried out to assess the levels of pesticide residues in the water of Meiliangwan Bay, Taihu Lake of China. The most commonly employed organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs) and herbicide atrazine were analyzed. The water samples were collected seasonally from Meiliangwan Bay within a period of one year. The pesticides were analyzed by gas chromatography (GC) with μECD or NPD after solid-phase extraction (SPE), which was confirmed by GC with an ion trap mass spectrometry (MS). The mean concentrations were 1.98 ng/l for lindane, 0.378 ng/l for heptachlor epoxide, 0.367 ng/l for p,p′-DDE, 0.496 ng/l for p,p′-DDD, 1.06 ng/l for p,p′-DDT and 51.6 ng/l for dichlorvos, 39.0 ng/l for demeton, 346 ng/l for dimethoate, 4.12 ng/l for methyl parathion, 11.6 ng/l for malathion, 2.17 ng/l for parathion and 217 ng/l for atrazine. Generally, low concentrations of OCP were found, whereas the concentrations of the OPPs and atrazine in the water of Taihu Lake were relatively high. Heptachlor epoxide and lindane were the two most commonly encountered OCPs while dichlorvos, demeton and dimethoate were found to have much higher concentrations and occurrences than other OPPs.  相似文献   

20.
对疏浚后的南京南湖底泥的TP、TN和COD释放规律、补水后的水质状况以及藻类演替规律进行了调查。结果表明,上覆水中TP平均质量浓度基本不随自来水补入量的增加而发生变化,TN和COD质量浓度随自来水补入量的增加而增大;水体中的TP、TN和COD含量总体呈上升趋势;从2005年3月中旬起,出现藻类的大量繁殖,在2005年7月发生水华,藻类优势种由裸藻、隐藻和小环藻演替为裸藻、栅藻和韦斯藻,藻类总量由2005年3月的3.7×106L-1上升到2006年4月的1.5×107L-1。  相似文献   

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