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2.
Human Influences on Water Quality in Great Lakes Coastal Wetlands   总被引:2,自引:0,他引:2  
A better understanding of relationships between human activities and water chemistry is needed to identify and manage sources of anthropogenic stress in Great Lakes coastal wetlands. The objective of the study described in this article was to characterize relationships between water chemistry and multiple classes of human activity (agriculture, population and development, point source pollution, and atmospheric deposition). We also evaluated the influence of geomorphology and biogeographic factors on stressor-water quality relationships. We collected water chemistry data from 98 coastal wetlands distributed along the United States shoreline of the Laurentian Great Lakes and GIS-based stressor data from the associated drainage basin to examine stressor-water quality relationships. The sampling captured broad ranges (1.5–2 orders of magnitude) in total phosphorus (TP), total nitrogen (TN), dissolved inorganic nitrogen (DIN), total suspended solids (TSS), chlorophyll a (Chl a), and chloride; concentrations were strongly correlated with stressor metrics. Hierarchical partitioning and all-subsets regression analyses were used to evaluate the independent influence of different stressor classes on water quality and to identify best predictive models. Results showed that all categories of stress influenced water quality and that the relative influence of different classes of disturbance varied among water quality parameters. Chloride exhibited the strongest relationships with stressors followed in order by TN, Chl a, TP, TSS, and DIN. In general, coarse scale classification of wetlands by morphology (three wetland classes: riverine, protected, open coastal) and biogeography (two ecoprovinces: Eastern Broadleaf Forest [EBF] and Laurentian Mixed Forest [LMF]) did not improve predictive models. This study provides strong evidence of the link between water chemistry and human stress in Great Lakes coastal wetlands and can be used to inform management efforts to improve water quality in Great Lakes coastal ecosystems.  相似文献   

3.
Understanding the impacts that influence water quality is critical to the development of best management practices at the large watershed scale. This study describes the spatiotemporal variation in surface water quality and identifies their main impact in the Haihe River basin, China. Multivariate statistical techniques are applied to analyze the similarities among the sampling sites and to identify the main pollution sources in surface water. Results show that: (1) the basin can be clustered into two regions, water quality being better in the mountainous vs. plain regions; (2) water quality improves due to implementation of a strict state policy on environmental pollution control, prodded by the hosting of the Olympic games in the cities of Beijing and Tianjin; and (3) agricultural and residential land uses as well as livestock‐breeding are the main sources affecting water quality in the mountainous regions, whereas rural waste discharge — including domestic waste sewage, human and animal feces, and solid waste — significantly influences water quality in the plain regions. The waste discharge of industrial factories may be a significant source of water pollution in the plain regions. Results indicate that the environmental management from pollution sinks and sources, long‐lasting legal framework, and adequate economic incentives should be improved to optimize the large‐scale watershed management under the background of the rapid development of countries like China.  相似文献   

4.
Models that accurately predict fecal coliform bacteria (FCB) concentrations, one of the most widely used measures of estuarine water quality, are needed to improve land use decision-making. Rapidly occurring changes in coastal land uses and the influence on water quality increases the urgency of having improved decision tools. For this study, samples were collected monthly from six coastal ponds, two tidal creeks and four shallow water wells for up to 212 years. These data were used along with other measures of environmental conditions and land classes within each watershed to construct quantitative relationships between combinations of variables and both total and presumed wildlife sources of FCB. Linear regression, bootstrapping and generalized additive modeling that incorporates both linear and nonlinear terms were used. Results of repeated simultaneous sampling on the same tide stage of ponds and downstream estuarine creeks suggest that most FCB come from wildlife and that the ponds effectively remove these bacteria except immediately following heavy rainfall. Predictive models for concentrations of total and presumed wildlife bacteria are provided along with simple measures to estimate watershed boundaries. It is proposed that these tools can be used to minimize impacts on receiving water body quality. The models can be used to test alternative development approaches within coastal watersheds similar to that found in the southeastern USA coastal zone as well as to evaluate specific proposed landscape alterations.  相似文献   

5.
Places of natural beauty and/or cultural value in the Mediterranean Sea are presenting adverse effects due to pollution. These environmental threats caused by point and nonpoint sources are mainly the reason why these areas represent “pollution-sensitive areas,” where the risk of deterioration is immediate. However, the risk will decrease and eventually disappear if protective measures are applied. In the present article, a multicriteria decision-making method is proposed for the prioritization of the Mediterranean sensitive coastal areas, taking into consideration criteria of pollution risk such as impact on human health, aquatic ecosystems, and socioeconomic value of the area. Weighting factors were then attributed to the different criteria according to their regional priorities, and a total pollution risk score was calculated for every sensitive area. However, some sensitive areas are more vulnerable than others because of their natural characteristics. Therefore, the total pollution risk score was then multiplied by a vulnerability weighting factor and a Total Sensitivity Score was calculated for every sensitive area. With this method, Mediterranean sensitive areas in coastal zones can be ranked on a priority list and then categorized according to their “sensitivity,” in a way that decision-makers can select the most urgent cases to direct their attention for the effective protection of the Mediterranean marine environment. The method is rapid and practicable and has already been used with existing data and information in several Mediterranean countries.  相似文献   

6.
This paper presents a process for estimating pollutant loads from water quality data, to improve catchment-scale modelling in the region for resource management purposes. It describes a program to estimate suspended sediment, total and dissolved nitrogen and phosphorus loads to the Tuross estuary from the Tuross River catchment (1810 km(2)) of coastal southeast Australia. Event-based water quality sampling results obtained during storm events in 2005 are presented. Event 1, during July 2005 was the largest storm event in terms of peak flow for 3.5 years. Other events monitored were also in July, November and December 2005. The early July 2005 event had a flow-weighted mean suspended sediment (SS) concentration during the first 4 days of 63 mg L(-1). Of the events monitored, this was unusual as it was preceded by drought and had the largest SS concentrations (peaking at 180 mg L(-1)) during the rising-stage. In contrast, the November event had a much lower flow-weighted SS mean (28 mg L(-1)), even though peak flow magnitudes were similar. The July and November 2005 events had peak flows of 12,360 and 11,330 ML day(-1). Low-cost rising-stage siphon samplers were used to collect samples during the rapidly rising phase of these events. The use of such samplers and consideration of time-lead/lag flow adjustments, quantified using cross-correlation analysis to account for hysteresis effects, were incorporated into the load estimation techniques. The technique is a potentially useful approach for understanding relationships between water quality concentrations and flow for modelling catchment source strengths and transport processes.  相似文献   

7.
Increasing salinity is one of the most significant and widespread forms of groundwater pollution in coastal areas. This paper presents the causes and impacts of saline water intrusion in coastal areas. Various causes of salt water intrusion, and approaches for the determination of its extent and various measures to control the salt water intrusion are described. An aquifer performance test (APT) approach is presented to identify the extent of existing salt water intrusion in the study area located in the southwest coastal region of Gujarat State (India). A resistivity based experimental technique is used to identify the quality of the groundwater available at different depths. A methodology is presented to assess the extent of available fresh and saline groundwater and to find out the limit up to which lower saline groundwater can be withdrawn for industrial purposes without affecting the upper fresh water layer which can be made available for domestic purposes.  相似文献   

8.
采用大气污染物超标指数、水污染物浓度超标指数、污染物浓度综合超标指数等3个指标,针对汶川地震极重灾区10个县市,评价了区域环境系统对社会经济系统的支撑能力。结果表明:10个县市中,环境承载力超载的县市有7个,接近超载的县市有3个。其中,9个县市的大气存在环境质量问题,4个县市的水环境质量存在问题,整个区域大气环境质量改善形式更为严峻。10县市的大气污染物中,O3、PM2.5、PM10普遍超标或接近超标,是影响区域大气质量的主要因素。在3指标中,又以PM10和PM2.5超标情况最为严重。大气污染在10个县市中具有明显的区域特征。都江堰市、彭州市、安县、绵竹市、什邡市等环成都城市圈的5县市大气污染物浓度超标指数普遍高于远离成都经济中心的5县市。根据影响水质的水污染物性质,及水环境影响因子排序分析,彭州市、什邡市在CODCr、P、N-NH3上有较高载荷,平武县在CODMn、DO两因子上载荷较大;汶川县的主要水环境影响因子是BOD5。根据在水污染因子上的载荷,10县市水污染特征归为集中污染型和面源污染型,以及混合污染三种类型。  相似文献   

9.
新乡市环境质量变化原因及应对措施   总被引:1,自引:0,他引:1  
通过对比分析新乡市2011年与2010年的监测数据,发现:环境空气质量、地表水河流控制断面有污染加重的趋势;气象条件、经济形势低迷、机动车尾气排放、交通干道堵塞是引起空气质量变化的原因;引起地表水质量变化的原因包括没有新鲜水源补给、结构性污染严重、其他城市来水污染、污水处理厂没有脱氮除磷设施。由此,提出了严格实行总量预算管理、转变经济增长方式、加强政府干预、加大环境监管、加强基础设施建设、河渠综合整治的改善环境质量的对策建议。  相似文献   

10.
In this paper we employ a stated preference environmental valuation technique, namely the choice experiment method, to estimate local public’s willingness to pay (WTP) for improvements in the capacity and technology of a sewage treatment plant (STP) in Chandernagore municipality, located on the banks of the River Ganga in India. A pilot choice experiment study is administered to 150 randomly selected Chandernagore residents and the data are analysed using the conditional logit model with interactions. The results reveal that residents of this municipality are willing to pay significant amounts in terms of higher monthly municipality taxes to ensure the full capacity of the STP is used for primary treatment and the technology is upgraded to enable secondary treatment. Overall, the results reported in this paper support increased investments to improve the capacity and technology of STPs to reduce water pollution, and hence environmental and health risks that are currently threatening the sustainability of the economic, cultural and religious values this sacred river generates.  相似文献   

11.
为调研设区的市立法权放开后各地立法进展,通过全国各省市政府网站(除港澳台外)等公开渠道收集整理的各设区的市"首次立法"(第一部实体法,简称"首法")立法情况,发现截至2017年7月,全国89%新获立法权设区的市已完成"首法"立项,超一半新获立法权设区的市已顺利出台"首法"。从"首法"立项类型来看,约40%设区的市"首法"关注环境保护,仅次于城乡建设与管理类立法,表明环境保护是各地"首法"立法关注的重点领域之一。从地方环境"首法"立项类型来看,水环境保护领域条例立项数最多,其次是生态保护领域和大气污染防治领域;从地方环境"首法"立项分布来看,水环境保护类条例多分布于位于水系末端的沿海各省,大气污染防治条例则主要集中于京津冀及其周边空气质量较差的区域。当前国家高度重视生态文明建设,各地有必要抓住地方立法这一机遇,研究出台地方环境条例,助力地方环境管理水平的提升。  相似文献   

12.
探究沿海城市化推进与海洋污染间的关系对沿海城市绿色发展具有重要意义。本文基于2006—2013年中国沿海46个地级市的海洋污染物浓度数据和遥感所得的夜间灯光亮度数据,运用面板空间计量技术从深度推进和广度推进两方面系统考察了沿海城市化对海洋污染的影响及作用机制,结果表明:以紧凑集约为特征的城市化深度推进与海洋污染之间存在着非线性的“U形”关系,而以规模扩张为特征的城市化广度推进只会单纯地加剧海洋污染。城市化深度推进会通过集聚效应和技术进步效应对海洋污染产生积极影响,而城市化广度推进过程中所带来的人口规模的扩大会加剧海洋污染,此外产业结构和绿色技术未能转型升级也是城市扩张加剧海洋污染的关键因素所在。本研究提出在海洋环境管理过程中,一是要加强区域合作,实现海洋污染的区域联防联控;二是应注重城市的紧凑集约化发展,发挥沿海城市化推进对海洋污染防治的正外部性影响;三是需推进海洋经济的绿色可持续发展,实现海洋经济发展与海洋环境污染的脱钩。  相似文献   

13.
Impervious surface is often used as an indicator of non-point source pollution in urban areas due to the strong relationship between percent impervious surface cover and water-quality impacts. In many cases, a threshold effect exists where water quality rapidly degrades above a given percent cover, but the exact threshold level appears to vary across regions. This study explores the relationship between pH, specific conductance, and percent impervious surface cover in the urbanizing coastal zone of New Jersey (USA) to determine the nature of the relationship in the region. The results of the analysis suggest the system is very sensitive to impervious surface, with a threshold potentially existing between 2.4% and 5.1% impervious surface cover. An examination of future conditions suggests that by 2020 water quality in more than 50% of the catchments in the study area will be negatively impacted by non-point source pollution associated with impervious surface.  相似文献   

14.
Seasonal and spatial variations in major ion chemistry and isotope composition in the rural-urban catchment of the Shigenobu River were monitored to determine the influences of agricultural and urban sewage systems on water quality. Temporal patterns of biochemical oxygen demand (BOD), total nitrogen (TN), total phosphorus (TP), and suspended sediment (SS) were examined at four sites in the rural-urban catchment. Urban land cover, incorporating the effects of increased population, domestic water use, and industrial wastewater, was positively associated with increases in water pollution and was included as an important explanatory variable for the variations in all water quality parameters. Significant trends were found in each parameter. BOD concentrations ranged widely, and were high in urban regions, due to the presence of a waste water treatment plant. TN and SS showed various trends, but did not vary widely, unlike TP. TP concentrations varied greatly, with high concentrations in cultivated areas, due to fertilizer use. Local water quality management or geology could further explain some of the variations in water quality. Non-point-source pollution exhibited strong positive spatial autocorrelation, indicating that incorporating spatial dimensions into water quality assessment enhances our understanding of spatial patterns of water quality. Data from the Ministry of Land Infrastructure and Transport (MLIT) and Environment Ministry (EM) were used to investigate trends in land management. Stepwise regression analysis was used to test the correlation between specific management practises and substance concentrations in surface water and sediment. MLIT and EM data for 1981-2003 showed an increase in TN, TP, and SS concentrations in surface water. High levels of fertilizer in dormant sprays and domestic water use were associated with high pesticide concentrations in water and sediment. This paper presents a novel method of studying the environmental impact of various agricultural management practises and recommends a management strategy that combines the use of reduced-risk pesticides with irrigation and non-irrigation periods in paddy fields.  相似文献   

15.
This work investigated water samples collected from Tapeng Lagoon and three neighbouring rivers (the Kaoping River, Tungkang River and Lingbeng River) in Taiwan, Republic of China. Canonical discriminant analysis was applied to identify the source of pollution in neighbouring rivers outside Tapeng Lagoon. The two constructed discriminant functions showed a marked contribution to all discriminant variables, and the total nitrogen, algae, dissolved oxygen and total phosphate were combined as the nutrient effect factor. The recognition capacities of the two discriminant functions were 95.6% and 4.4%, respectively. The water quality in the Kaoping River most strongly controlled the water quality in Tapeng Lagoon. Disassembling the oyster frames and fishery boxes had improved the water quality markedly. The methodology and results provide useful information concerning watershed management and may be applicable to other basins with similar properties that are experiencing similar coastal environmental issues.  相似文献   

16.
The coastal waters at many beaches in California and the United States are afflicted with fecal pollution, which poses a health risk for people exposed to the water through recreational activities such as swimming, surfing, and diving. Identifying sources of pollution is complicated by oceanographic transport/mixing processes and the nonconservative behavior of microorganisms exposed to sunlight and hostile marine conditions. This article investigates the variation of fecal indicator bacteria (FIB) concentrations in the surf zone and the adjacent coastal marsh by applying autocorrelation and cross-correlation analyses that illustrate solar and tidal modulations. A steady state bioreactor model was developed to explain solar inactivation in the surf zone, whereas a dynamic model was applied to explain tidally influenced disturbances in the coastal marsh. These models applied to intensive monitoring datasets on FIB and environmental variables have provided insights into the biologic and physical processes controlling coastal water quality, specifically the influence of sunlight and tides on bacterial levels.  相似文献   

17.
This paper investigates index models as a tool to estimate the risk of N and P source strengths and loss at the catchment scale. The index models assist managers in improving the focus of remediation actions that reduce nutrient delivery to waterbodies. N and P source risk factors (e.g. soil nutrient concentrations) and transport risk factors (e.g. distance-to-streams) are used to determine the overall risk of nutrient loss for a case study in the Tuross River catchment of coastal southeast Australia. In the development of the N index model for Tuross, particulate N was considered important based on the observed event water quality data. In contrast to previous N index models, erosion and contributing distance were therefore included in the Tuross River catchment N index. Event-based water quality monitoring, and soil information, or in data-poor catchments conceptual understanding, are essential to represent catchment-scale processes. The techniques have high applicability in other catchments, and are complementary to other modelling techniques such as process-based semi-distributed modelling. Index models generally provide much more detailed spatial resolution than fully- or semi-distributed conceptual modelling approaches. Semi-distributed models can be used to quantify nutrient loads and provide overall direction to set the broad focus of management. Index models can then be used to refine on-the-ground investigations and investment priorities. In this way semi-distributed models can be combined with index models to provide a set of powerful tools to influence management decisions and outcomes.  相似文献   

18.
The Pearl River (Zhujiang) is the largest river system in southern China. The river, which is approximately 2200 km long, discharges into the South China Sea through an extensive deltaic area to the west of Hong Kong. Water quality in the river is under threat from a variety of sources associated with industrializationand urbanization in the Pearl River Delta Region (PRDR). Hong Kong's location on the eastern bank of the Pearl River estuary means that the quality of its western marine waters is likely to be increasingly influenced by the Pearl's pollution burden. Little published material exists on pollution in the Pearl River, or the potential impacts of transboundary pollution on marine water quality in Hong Kong. This paper focuses on this issue of transboundary water pollution between the Delta Region and Hong Kong. Specifically, we present the results of a preliminary analysis of water quality data for the Pearl River. The paper demonstrates that the major potential problem affecting the Pearl River is organic pollution, and that the principal sources of pollution affecting the Pearl River estuary, and consequently Hong Kong's western waters, are the Shenzhen River, the upstream Guangzhou section of the Pearl River, and the Dongguan Canal. We estimate that less than 5% of untreated domestic sewage discharges affecting the estuary derive from Hong Kong itself. The paper also discusses the implications of transboundary pollution in the context of environmentalpolicy making in Hong Kong and argues that more extensive and effective co-operation and collaboration between Hong Kong and mainland agencies should be developed to address these concerns.  相似文献   

19.
"十一五"期间,秦皇岛市环境质量总体趋于好转。环境空气质量Ⅱ级以上天数始终保持在350天以上,综合污染指数明显下降;城市集中式饮用水源地水质达标率100%;地表水河流Ⅲ类断面比例提高了43.8%;劣Ⅴ类断面比例降低了35.7%。近岸海域海水水质达标率100%,海水浴场水质良好。但存在局部空气污染严重、部分河段水质恶化等主要环境问题,针对上述问题提出了总量减排、污染物联控等对策建议。  相似文献   

20.
/ The coastal environment of Kuwait has been under considerable stress since the onset of the oil era in the late 1950s and early 1960s. Oil, sewage, and industrial pollution were believed to be the main environmental problems in the coastal zone. The huge oil spill and destruction caused by the Gulf War further complicated those problems. In this article, the temperature, pH, salinity, and total dissolved sulfide (TDS) of the interstitial water in the intertidal zone and the water content and total organic carbon (TOC) of the intertidal sediment were investigated. The purpose of the study was to understand the effect of the physicochemical characteristics on the intertidal benthic ecology and to identify the level and sources of organic pollution in the intertidal zone. The study results indicated that the prevailing harsh environmental conditions, especially high temperature and salinity, restricted benthic fauna diversity and led to the development of a fragile intertidal ecosystem. The fauna inhabiting the intertidal zone was dominated by a few species probably living at their limit of tolerance. Organic pollution was evident mainly in Sulaibikhat Bay and to a lesser extent in Kuwait City waterfront and Shuaiba coast in the south. The pollution was attributed mainly to land-based sources such as the occasional discharge of raw sewage through stormwater outlets, the direct oil spillage, and industrial effluents from refineries, oil terminals, and petrochemical plants. Quantitative analysis was inconclusive in establishing a significant correlation between the chemistry and composition of the benthic fauna. However, close examination of sites with high TOC and TDS concentrations indicated that the benthic fauna in those sites was showing evidence of degradation. A number of strategies were recommended to ensure protection and sustainable management of the coastal environment.KEY WORDS: Intertidal environment; Pollution; Total organic carbon; Dissolved sulfide; Interstitial water; Benthic fauna  相似文献   

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