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1.
    
Eutrophication, or the enrichment of lakes and reservoirs with plant nutrients such as nitrogen and phosphorus, is an ongoing concern facing human societies around the world. Once thought to have been resolved using engineering approaches such as municipal wastewater treatment and storm water management, the problem of nutrient enrichment not only persists, but even continues to increase, being manifested in harmful algal blooms, limitations on access to safe drinking water supplies, and related concerns associated with fresh water in lakes and reservoirs. The continuing concern surrounding eutrophication fulfils the many attributes of a ‘wicked’ or complex problem facing society. This report reviews seriatim the ten attributes of a wicked problem, and the implications of these attributes for lake and reservoir management are discussed. Recognition of eutrophication as a wicked problem requires site‐specific approaches, based on specific knowledge of individual water bodies, as well as an ongoing commitment to lake and reservoir management to respond to new manifestations of the problems of nutrient enrichment as they continue to be revealed over time.  相似文献   

2.
基于文献计量学的中国地下水微生物研究现状分析   总被引:1,自引:0,他引:1  
为了揭示我国地下水微生物研究现状与重点,为后续污染修复提供参考,利用Excel、CNKI可视化分析模块和CiteSpace软件对国内该领域397篇期刊论文和199篇硕博论文进行文献计量学分析。结果显示:中国地下水微生物研究主要围绕地下水污染开展,一方面使用多种修复技术对地下水污染环境进行生物修复,为地下水污染修复提供技术支持,另一方面利用分子生物学技术对地下水污染环境进行监测,为地下水污染修复提供理论支撑。张胜研究员、林学钰院士、刘菲教授、王焰新教授和席北斗研究员是该领域不同研究阶段的重要学者,吉林大学、中国地质大学(北京)和中国地质科学院水文地质环境地质研究所在该领域具有较强学术影响力。在生态文明建设的迫切需求下,充分发挥微生物群落在地下水污染修复中的作用潜力仍是当下研究的重点。  相似文献   

3.
    
The physical and chemical variables of the water, and the composition and structure of the zooplankton communities, in Três Marias and Furnas Reservoirs in Minas Gerais, Brazil, were compared to characterize these environments in relation to their trophic state. Higher values of electrical conductivity and chlorophyll‐a, total solids, suspended organic matter and total nitrogen concentrations were recorded in Três Marias Reservoir. Higher water transparency and nitrite and nitrate concentrations were observed in Furnas (P < 0.000). Higher zooplankton densities were always obtained in Três Marias Reservoir and, during the rainy period (P < 0.000), with mean values in the dry and rainy periods of 23 721 and 90 872 org m?3, respectively, in Três Marias Reservoir and 9022 and 40 434 org m?3, respectively, in Furnas Reservoir. Copepoda was the dominant group in both reservoirs, mainly the younger stages (nauplii and copepodids). Based on the absolute and relative values, the contribution of rotifers was higher in Três Marias Reservoir than in Furnas Reservoir. Although the Trophic State Index, based on water transparency and chlorophyll‐a and total phosphorus concentrations, indicated an oligotrophic state for both reservoirs, the higher densities of the zooplankton community in Três Marias Reservoir, as well as the predominance of cyclopoids and smaller‐sized species such as bosminids, characterized this environment as mesotrophic. Larger‐sized species such as calanoids, daphniids and sidids in Furnas Reservoir characterized the better water quality of this reservoir.  相似文献   

4.
淀山湖富营养化现状及生态修复措施分析   总被引:1,自引:0,他引:1  
根据2008—2010年淀山湖水质监测数据,评价该湖富营养化趋势。结果显示,2008年后,淀山湖的富营养化程度呈改善趋势,但水体富营养化存在区域差异。主要表现在:①2008—2010年的整个湖区水体中主要的富营养化指标TN、TP、SS、Ch-la质量浓度均呈下降趋势;②淀山湖上游来水区水体中TN、TP质量浓度比下游出水区高,综合营养状态指数同样也高;③淀山湖每年夏季暴发蓝藻水华的水域面积在不断减小。结果表明,淀山湖东南区域富营养化程度最轻,水生植物对水体净化、生态系统恢复具有重要价值;淀山湖的生态系统在逐步恢复。为使生态系统能巩固并形成良性循环,一些影响因素亟待解决。  相似文献   

5.
  总被引:1,自引:0,他引:1  
This paper presents the phytoplankton succession during two successive years in Lake Bourget, a deep subalpine lake recovering from eutrophication. A drastic reduction of the watershed phosphorus loading in 1980 stopped lake eutrophication. At present, the lake has nearly reached constant winter (January–February) nutrient concentrations. However, during the 2 years of the study, the phytoplankton data set shows a great interannual variability, which is analysed on the basis of the meteorological forcing variables.  相似文献   

6.
    
This paper provides data on the changing character of river restoration within one country within a single policy and legislative framework. The information gathered was based on web searches, meetings and questionnaire responses with organizations and individuals working as environmental policy developers, stakeholders and practitioners of catchment management and river restoration. The paper utilizes this information to explore generic issues promoting and constraining a move to integrated catchment scale river restoration. Catchment scale river restoration was defined as ‘any river restoration activity that singly, or in combination, restores natural catchment processes and a naturally functioning ecosystem and brings benefit or environmental services to the whole catchment and not just to the site of restoration’. The river restoration project data compiled showed that the number of projects in Scotland is on a strong upward trajectory, but the number of catchment scale projects is still limited. The data also showed a trend towards a range of underpinning reasons for river restoration. Traditionally the reasons for river restoration in Scotland have been strongly fisheries focussed, with another key driver being biodiversity conservation. Sustainable flood management and climate change adaptation are seen as emerging drivers of river restoration. In terms of the individuals interviewed, most appreciated that river restoration can bring about multiple benefits and should be underpinned by a good understanding of catchment processes. Our overall assertion based on our study is that unless there is a fundamental paradigm shift, a change in the nature and level of funding for river restoration and a single organization is given overall authority to direct river restoration. ‘business as usual’ will continue and the benefits of catchment scale river restoration will be limited. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

7.
    
The Governments of the Provinces located in Patagonia, Argentina, promote the intensive breeding of salmonids in the Andean Patagonian region. Although annual production is low (450 ton ha–1 year–1), some effects are significant. Waste produced by salmonid breeding (feed losses, faeces and excretion) increases nutrient and organic matter concentrations, which cause modifications of water quality, sediments and biota. A consequent risk is the elevation of eutrophication levels. Possible changes in water composition, sediments, algae and wild fish populations were studied. Sites affected by fish farming showed increased nutrient concentration, and phytoplankton and periphyton biomass. Chlorophyll a was similar at both sites (affected and unaffected by fish farm sites). Sediments clearly reflect fish farm waste inputs: total phosphorus and organic matter increased 12‐fold and fourfold, respectively. The species present in the gill‐net catches were the autochthonous Percichthys trucha, Odontesthes hatcheri, Diplomystes viedmensis, and the introduced salmonids Oncorhynchus mykiss, Salmo trutta, Salmo salar sebago and Salvelinus fontinalis. About 50% of the total catch was salmonids. A major portion of the catch per unit weight was composed of rainbow trout, followed by perch. The catch per unit weight obtained for this reservoir agrees with the range of values previously determined ( Quiros 1990 ) for Patagonian reservoirs. Compared with previous studies by Freyre et al. (1991) , a variation in catch composition exists. This consists mainly of an increase in the numbers and condition of O. mykiss and a decrease in P. trucha. Presence of fish that escaped from hatcheries, recognizable by their eroded fins, was observed; particularly in a sampling station near the fish cage systems. Variations in catches could be caused by cyclical changes in fish populations ( Wooton 1991 ), by direct and indirect effects of intensive fish farming, or by a combination of both events, and can only be understood through long‐term studies of catch variation.  相似文献   

8.
The problem of managing water scarcity by resorting to complex interconnected multi-source water systems needs to utilize management optimization techniques analyzing aspects of water quantity and quality in a common strategy. In the southern regions of Mediterranean Europe, the greater part of water resources for supply systems are derived from artificial reservoirs and water systems can become quite complex since they interconnect several sources and demand centers, as indeed occurs in the Region of Sardinia (Italy). A simplified approach to the requirement to insert water quality aspects in the mathematical optimization model can be achieved by examining the trophic conditions of reservoirs. Trophic State Indexes (TSI) based on Carlson’s (1977) make it possible to insert quality constraints in the water management optimization model also considering complex multi-reservoir and multi-user systems. Model formalization and implementation by the optimization toolkit WARGI (Water Resource system optimization aided by Graphical Interface) (Sechi and Zuddas 2000; Manca et al. 2004; Salis et al. 2005) is illustrated in this paper. The usefulness of a mixed quantity–quality optimization approach has been confirmed by WARGI application to a real multi-reservoir water resources system in southern Sardinia. The optimization model remains computationally efficient dealing with this complex multi-reservoir system and the obtained results can be seen as a reference target in a subsequent simulation phase.  相似文献   

9.
基于分形理论的水体富营养状况评价及其验证   总被引:1,自引:0,他引:1  
在简要介绍分形维数算法的基础上,以乌梁素海2006年5月实测资料为例,初步分析分形理论在水体营养状况评价中的适用性;将基于分形理论的评价结果与国家环境保护部推荐使用的综合营养状态指数法评价结果进行比较分析。结果表明:在对22个采样点的评价中,二者评价的一致性达到91%。两种方法的评价结果仅有两个采样点不同。从全湖的评价结果看,乌梁素海已经达到富营养重富营养水平,与已有的研究成果相一致。评价结果充分说明分形维数法可以应用于乌梁素海的富营养化评价研究,但其在其他水体的普适性尚待进一步验证。另外,分析了分形理论在水体营养状况评价研究中存在的问题和不足,并对未来的发展趋势进行展望。  相似文献   

10.
依据我国湖库富营养化评价标准和支持向量机(SVM)原理及方法,构建基于交叉验证(CV)的CV-SVM湖库营养状态识别模型,采用随机内插的方法在各分级标准阈值间生成训练样本和测试样本,在达到预期识别精度后将模型运用于全国24个湖库营养状态的识别,并与投影寻踪法、评价指标法和神经网络评价法的识别结果进行比较。结果表明:基于线性核函数的CV-SVM模型对于随机生成的训练样本和测试样本的正确识别率分别达到97.8%和97.3%(5次平均),对全国24个湖库营养状态的识别结果与采用投影寻踪法、评价指标法和神经网络评价法的识别结果基本相同,模型具有泛化能力强、识别精度高、收敛速度快、不易陷入局部极值等特点。  相似文献   

11.
    
Many reservoirs provide multiple benefits to people around the world, in addition to primary uses such as irrigation. Thus, reservoir management should address their multiple uses. The water quality of ten irrigation reservoirs in Sri Lanka was examined in the present study with the objective of better understanding the effects of hydrological regimes on reservoir water quality and trophic state. Basic limnological parameters pertinent to the nutrient loads to, and trophic state of, the reservoirs were collected from June 2013 to February 2016. The sampling period was arbitrarily divided into two periods of approximately similar duration (period 1 = June 2013–September 2014; period 2 = October 2014–February 2016) to investigate whether or not there was a seasonal variation in the water quality parameters. Although temporal and spatial variations were observed, most water quality parameters were within the levels acceptable for drinking water standards. The 10 reservoirs were also ordinated by principal component analysis (PCA) on the basis of the water quality parameters of the two sampling periods in a two‐dimensional score plot. Reservoirs in the first principal component (PC1) axis were represented by negative scores attributable to the dissolved oxygen concentration and pH and, to a lesser extent, by electrical conductivity and chlorophyll‐a concentration. Positive scores in PC1 were represented by reservoirs with a score loading attributable to alkalinity, nitrate concentration, Secchi depth, temperature and seston weight and, to a lesser extent, from the total phosphorus concentration. There was a significant negative correlation of PC1 scores with relative reservoir water‐level fluctuation (RRLF; the ratio of mean reservoir water‐level amplitude to mean reservoir depth). Furthermore, Carlson's trophic index also were influenced by RRLF, although not by hydraulic retention time (HRT), indicating allochthonous nutrient inputs into the irrigation reservoirs were mainly governed by RRLF, but not by HRT. Thus, the results of the present study provide useful insights into achieving desirable reservoir water quality through the manipulation of the hydrological regime.  相似文献   

12.
湖、库富营养化机理研究综述   总被引:3,自引:0,他引:3  
综述了湖、库富营养化机理研究现状,内容包括水体富营养化过程各主要因素间的相互关系及其表现:藻类增长限制因子,叶绿素a与总氮、总磷浓度的关系,\"水华\"发生的水文气象条件;富营养化过程的藻类表现:典型污染指示种、群落多样性及藻类生长潜力;湖泊生态系统健康概念与湖泊生态系统的物质循环理论。指出富营养化实质是生态失衡。  相似文献   

13.
    
The external loading of 14 lakes in the Wielkopolska National Park was calculated, including nitrogen and phosphorus loads from point, diffuse and dispersed sources, precipitation and recreation. The basic source of nitrogen and phosphorus for most lakes in the Park is the export of diffuse pollution from the catchment area. Only four lakes are contaminated by sewage, which accounts for 0.1–61.2% of total nutrient loading. Annual unit area loads of phosphorus and nitrogen estimated for each lake were 2–51 times higher than Vollenweider’s critical loading levels. Estimated mass loading and annual unit area loads of nutrients for each lake were compared with lake water quality, expressed as the trophic state index. Analysis of the physico‐geographical structure of the catchment area and natural resistance of lakes to external input of nutrients allowed us to assess the role of the catchment in the deterioration of water quality and to indicate the protective measures required.  相似文献   

14.
根据水利部《开展2011年西部地区典型湖库生态调研》技术要求,首次由甘肃省水环境监测中心与黄河流域水环境监测中心技术人员组成联合调查组,确定调研技术路线和方法;选定甘肃省境内的大苏干湖、刘家峡水库、尕海、天池等4个湖库作为西北内陆代表典型湖库;现场采取代表水样14个,并获取其相关基本信息资料;依据国家标准和规范进行水质检测、评价与特征分析;得出了西北内陆典型湖库现状水质为Ⅲ类至劣Ⅴ类,水体营养状态为中营养至富营养等现状特征.  相似文献   

15.
16.
加强太湖流域综合管理维护河湖健康生态   总被引:2,自引:0,他引:2  
以太湖流域为例,分析了流域水生态环境问题和河湖生态健康的评价指标,阐明了流域综合管理对维护河湖生态健康的重要性,提出了有效的流域管理目标在于建立人类活动与生态环境之间平衡的观点.维护流域生态健康所必需的综合管理措施,首先是要形成流域综合管理机制,建立高效、权威的流域管理机构,通过有效的流域综合管理来协调人类活动与水生态环境的兼容性,对于已经受损的流域河湖生态系统需要采取有效措施加以修复或恢复.另外,提出应把河湖生态健康作为衡量可持续发展和流域管理成效的尺度之一.  相似文献   

17.
    
The aim of this paper is twofold: to present and discuss practically useful management criteria from different perspectives of lake management (fishery, recreation, conservation, monitoring of water quality and use of water for irrigation and drinking), and to put these criteria into the context of a holistic lake ecosystem model, LakeWeb, which accounts for production, biomasses, predation and abiotic/biotic feedbacks related to nine key functional groups of organisms constituting the lake ecosystem. These are phytoplankton, benthic algae, macrophytes, bacterioplankton, herbivorous zooplankton, predatory zooplankton, zoobenthos, prey fish and predatory fish. The LakeWeb model also includes a mass‐balance model for phosphorus and calculates bio‐uptake and retention of phosphorus in these groups of organisms. It also includes submodels for the depth of the photic zone and lake temperature. The LakeWeb model is driven by few and readily accessible driving variables and it has been extensively tested and shown to capture fundamental lake foodweb interactions very well, which should lend credibility to the scenarios discussed in this paper regarding the conditions in Lake Batorino, Belarus. The LakeWeb model offers a tool to address important, often very complex, scientific problems in a realistic manner. The first scenario describes the changes after 1990 when there was a drastic reduction in the use of fertilizers in agriculture because of political changes and the corresponding changes in lake characteristics and foodweb structures utilizing the given management criteria. The second scenario describes, for comparative purposes, the probable alterations in the lake foodweb related to global climatic changes; in this case, warming and increased temperature variations. This study indicates that there are several similarities between eutrophication and increases in temperatures, which are discussed in this paper along with the mechanistic reasons related to such changes by using a set of general management criteria.  相似文献   

18.
19.
    
Bütgenbach Reservoir is situated in the High Ardennes plateau in eastern Belgium (50°25′N; 6°13′E). It is used principally for flood control and for production of hydroelectric energy. It has been subjected to a previous series of studies because of its eutrophication problems and their impacts on the local economy. Bütgenbach Reservoir was emptied during spring 2004 for dam restoration, being refilled in mid‐September of the same year. Selected physicochemical and biological parameters (temperature, dissolved oxygen, pH, inorganic and organic nutrients, chlorophyll‐a) were measured fortnightly during the lake's productive season (mid‐April to mid‐October 2005) at three sampling sites throughout the water column. The water quality conditions after refilling of the lake were compared to previous studies accomplished at the same sampling sites (prior to emptying the lake). The actual trophic status was mesotrophic to eutrophic, based on the combination of total phosphorous and chlorophyll‐a concentrations, as well as water transparency. Bütgenbach Reservoir generally exhibits good water quality, based on the French water quality system SEQ‐eau. A longitudinal decrease in water quality was observed from upstream to downstream, because mainly of the differences in lake bottom morphology and water residence time, and their impacts on nutrient distribution in the lake.  相似文献   

20.
国外流域综合管理模式对我国河湖管理模式的借鉴   总被引:2,自引:0,他引:2  
针对我国现阶段河湖管理采用流域管理和行政管理相结合的模式,管理实践中存在着流域管理机构与主导政府机构权责不清、公众有效参与不足的问题,以美国五大湖流域、英国东南流域、澳大利亚墨累-达令流域、法国卢瓦尔-布列塔尼流域等为例,对美国、英国、澳大利亚、法国、德国5个主要西方发达国家的各自最有特色的河湖管理模式中流域管理机构、主导政府机构、公众参与、流域管理特点进行了分析及归纳总结,以期对我国最近提出的流域综合管理提供参考。  相似文献   

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