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1.
The European Water Framework Directive (WFD) establishes a framework for the protection of water bodies. The aim of the Water Framework Directive (WFD) is to ensure sustainable management of groundwater, freshwater and marine water in the European Union, such that a minimum "good ecological status" will be obtained by 2015. We used background morphometric, hydrologic, physico-chemical and biological data, in order to highlight the ecological status of the natural Greek lakes using also the Driving-Pressure-State-Impact-Response (DPSIR) approach in order to link the driving forces and further the pressures with the present state of the lakes' ecosystems. In addition detailed biodiversity and habitat typology data are provided. The assessment of the DPSIR approach under the view of WFD provided a quite clear identification of pressures and the subsequent impacts of the qualitative status of the Greek lakes.  相似文献   

2.
Biological elements, including phytoplankton, phytobenthos, macrophytes, benthic invertebrates and fish, are employed by the EU Water Framework Directive (WFD) 2000/60/EC as ecological indicators for the assessment of surface waters. The use of primary producers (phytoplankton, phytobenthos and macrophytes) for water quality assessment has a long history, and several methods have been developed worldwide. In this study, we used these three communities to assess the ecological status of five natural lakes located in the Aquitaine region (southwest France). Several biological indices used in lakes from other European countries or in French rivers were employed and compared among the three communities. Each primary producer provided complementary information about the ecological status of the lakes, including the invasiveness of exotic taxa. Regardless of the producer community used, the response to the environment, as reflected by the indices (adequate for each community), was similar: Lakes Cazaux, Lacanau and Hourtin showed the best ecological status and Parentis and Soustons the worst. Phytoplankton diagnosis reflected and integrated unambiguously the water quality of the lakes, as demonstrated by the strong relationships between the phytoplankton index and the trophic status criteria. This community appeared as the best indicator, especially when macrophytes were absent. The methods applied here represent a potential tool for the assessment of the ecological status in the context of WFD, but they need to be refined. We propose modifications for phytobenthos index initially tailored for running waters for adequate use in lentic ecosystems. Indices for the three primary producers should be modified to incorporate exotic species which may provide information on potential biodiversity losses.  相似文献   

3.
Surface water acidification was identified as a major environmental problem in the 1960s. Consequently, a liming program was launched in Sweden in the 1970s. The primary purpose of liming is to restore conditions that existed prior to acidification. To reach this goal, as well as achieve 'good status' (i.e. low levels of distortion resulting from human activity) in European freshwaters until 2016 under the European Union Water Framework Directive, lake data are required to define reference conditions. Here, we compare data from chemical/biological monitoring of 12 limed lakes with results of paleolimnological investigations, to address questions of reference conditions, acidification, and restoration by liming. Using diatom-based lake-water pH inferences, we found clear evidence of acidification in only five of the 12 lakes, which had all originally been classified as acidified according to monitoring data. After liming, measured and diatom-inferred pH agree well in seven lakes. The sediment record of three of the five remaining lakes gave ambiguous results, presumably due to sediment mixing or low sediment accumulation rates. It is difficult to determine whether liming restored the lakes to a good status, especially as some of the lakes were not acidified during the twentieth century. In addition to acid deposition, other factors, such as natural lake and catchment ontogeny or human impact through agricultural activity, influence lake acidity. This study shows that monitoring series are usually too short to define reference conditions for lakes, and that paleolimnological studies are useful to set appropriate goals for restoration and for evaluation of counter measures.  相似文献   

4.
In this study, classification trees were combined with the Water Framework Directive (WFD)-Explorer, a modular toolbox that supports integrated water management in a river basin to evaluate the impact of different restoration measures on river ecology. First, the WFD-Explorer toolbox analysed the effect of different restoration options on the abiotic river characteristics based on the water and substance balance embedded in the simulation environment. Based on these abiotic characteristics, the biological index Biological Monitoring Working Party for Vietnam was then predicted by classification trees that were trained on biological and abiotic data collected in the Du river basin in northern Vietnam. The ecological status of streams in the basin ranged from nearly pristine headwaters to severely impacted river stretches. Elimination of point sources from ore extraction and decentralised domestic wastewater treatment proved to be the most effective measures to improve the ecological condition of the Du river basin. The combination of the WFD-Explorer results with data-driven models enabled model application in a situation where expert knowledge was lacking. Consequently, this approach appeared promising for decision support in the context of river restoration and conservation management.  相似文献   

5.
Denmark has a long tradition of monitoring the aquatic environment. Previous monitoring has mainly focused on loss of nutrients and subsequent impacts on the biological structure in lakes and coastal areas. However, as part of the third Action Plan for the Aquatic Environment more emphasis has been put on stream ecology. The present paper describes background, strategy and content of the new NOVANA stream programme, which will run for the period 2004–2009. The new programme will encompass more than 800 stations covering all stream types in Denmark and monitoring will include three biological quality elements (macrophytes, macroinvertebrates and fish) as well as physico-chemical features and hydromorphological elements. In addition, the new programme integrates monitoring of elements both in the stream itself and in the riparian zone. Compliance with important European Commission Directives such as the Water Framework Directive and the Habitat Directive is discussed.  相似文献   

6.
Mediterranean wetlands represent unique repositories of biodiversity, but these ecosystems are increasingly threatened by human-induced habitat loss. Seventy percent of Greek wetlands (ponds, mires, marshes, etc.) have been lost in the past 80 years due to human intervention. In Greece habitat types of mires, listed in Directive 92/43/EEC, have been recorded in a few locations, one of the most important is Kalodiki wetland. Eutrophication key elements were determined at four sampling stations throughout 1 year in order to monitor the trophic conditions. Moreover, the zooplankton community was described as biological element relevant in the assessment of the ecological status of Kalodiki wetland. Kalodiki wetland exhibits nutrient concentrations corresponding to eutrophic conditions while according to chlorophyll-a values it is classified between mesotrophic and eutrophic status depending mostly on the sampling period. As concerning zooplankton community, it appears poor in species and dominated by small-sized organisms, which is generally typical of eutrophic, disturbed systems. Differences among zooplankton assemblages over seasons as well as among sampling sites highlight the role of both abiotic and biotic factors.  相似文献   

7.
The European Water Framework Directive (WFD) requires the definition of near-natural reference conditions to determine the extent of water bodies' deviation from "good ecological status" caused by stress gradients. However, the classification of ecological quality depends on the assessment method applied and the stressor concerned. While assessment methods that are generally applicable would be favourable, many European countries employ the locally developed water quality metrics that assess the impact of organic pollution (including eutrophication) and the associated decrease in dissolved oxygen. These indices do not specifically address stress from organic toxicants, such as pesticides. The aim of this study was to examine the performance of presently used assessment methods to identify reference conditions of non-contaminated streams in five selected European river basins, covering the geographical region from Spain to Finland, as a crucial prerequisite to indicate toxic gradients. The analysis comprised the Belgium biotic index (BBI), the biological monitoring working party (BMWP) scoring system and the revised German saprobic index. For comparison, we included an adaptation of the recently developed SPEAR index. In two previous field studies, this metric highly correlated with measured pesticide gradients. In this study, SPEAR was the only indicator that was generally applicable to all monitoring data and capable of determining "high ecological status" of reference conditions in all basins. Thus, based upon previous and own results, the authors suggest the species at risk (SPEAR) index to be potentially useful as a European-wide index to address deviations from "good ecological status" due to organic toxicants and recommend it for consideration in integrated water-resource evaluations under the WFD.  相似文献   

8.
The priority substances of List I, 76/464/EEC Directive, some of which belong to the new Water Framework Directive 2000/60/EC, have been monitored in the surface waters of Greece through the developed network of 53 sampling stations. The analytical methods used for the determination of these substances included Purge and Trap-Gas chromatography-Mass spectrometry for volatile and semivolatile organic compounds, Gas Chromatography-Electron Capture Detection for organochlorine insecticides, High Performance Liquid Chromatography for pentachlorophenol and Atomic Absorption Spectrometry for metals. The results have shown the presence of several priority substances in Greek surface waters, in most cases at concentrations well below the regulatory limits. However, non-compliance was observed for a limited number of compounds. The monitoring network and the analytical determinations have to be expanded to more water bodies and more priority substances, in order to safeguard the quality of Greek surface waters.  相似文献   

9.
Water management is becoming increasingly important as the demand for water grows, diversifies, and includes more complex environmental concerns. The Water Framework Directive (WFD) seeks to achieve a good ecological status for all European Community water bodies by 2015. To achieve this objective, economic consideration of water management must be given to all decision-making processes. Exemption (time or level of stringency) from the objectives of the EU Directive can be justified by proving that the cost of implementing measures is disproportionate to the benefits. This paper addresses the issue of disproportionate costs through a cost-benefit analysis (CBA). To predict the costs, the function costs method is used. The quantification of environmental benefits is more complex, because they are not determined by the market. As an alternative to stated preference methods, we use the distance function approach to estimate the environmental benefits of improving water quality. We then apply this methodological approach to a Mediterranean River Basin in Spain. The results show that the achievement of good status could not be rejected based on the criterion of disproportionate costs in this river basin. This paper illustrates that CBA is a useful tool to inform policy and decision making. Furthermore, it is shown that economics, particularly the valuation of environmental benefits, plays a crucial role in fulfilling the environmental objectives of the WFD.  相似文献   

10.
11.
The European Water Framework Directive 2000/60/EC aims to achieve a good ecological status of all surface water bodies in Europe. The definition of the ecological status is based on the hydromorphological, hydrochemical, and hydrobiological features of water bodies. Numerous methods are applied for the purpose of hydromorphological status assessment. This study attempts to compare four different methods (EcoRivHab, LAWA Field and Overview Survey, and Rapid Bioassessment Protocol) that were applied at two study areas in the Czech part of the Elbe River Basin. The selected catchments represent areas with different sizes and physical geographic as well as socioeconomic characteristics. All the methods applied showed the capacity to identify the natural and even the completely changed reaches and provided good information on the river physical habitat state. However, they are varied from the viewpoint of the number of parameters, number of monitored zones, time and knowledge demands of the performed assessment.  相似文献   

12.
The European Water Framework Directive (WFD) establishes a framework for the protection of estuarine and coastal waters, with the most important objective being to achieve 'good ecological status' for all waters, by 2015. Hence, Member States are establishing programmes for the monitoring of water quality status, through the assessment of ecological and chemical elements. These monitoring programmes can be of three types: surveillance monitoring; operational monitoring (both undertaken on a routine basis); and investigative monitoring (carried out where the reason of any exceedance for ecological and chemical status is unknown). Until now, nothing has been developed in relation to investigative monitoring and no clear guidance exists for this type of monitoring, as it must be tackled on a 'case-by-case' basis. Consequently, the present study uses slag disposal from a blast furnace, into a coastal area, as a case-study in the implementation of investigative monitoring, according to the WFD.In order to investigate the potential threat of such slags, this contribution includes: a geophysical study, to determine the extent of the disposal area; sediment analysis; a chemical metal analysis; and an ecotoxicological study (including a Microtox test and an amphipod bioassay). The results show that metal concentrations are several times above the background concentration. However, only one of the stations showed toxicity after acute toxicological tests, with the benthic communities being in a good status. The approaches used here show that contaminants are not bioavailable and that no management actions are required with the slags.  相似文献   

13.
We use data from a survey of several hundred lakes in the northeastern United States by the U.S. Environmental Protection Agency to illustrate an approach to identifying promising indicators of lake condition. We construct a hypothetical gold standard of water quality from the first principal component of 16 chemical variables measured in the lakes, and examine its associations with 71 candidate indicators based on measurements of human activity, birds, fish and zooplankton in the lakes or their watersheds. Nonparametric summaries of these associations – based on rank correlations and receiver-operating-characteristic curves – suggest that variables summarizing the extent of human disturbance are generally the strongest indicators. To the extent that our water-quality variable is a useful proxy for ecological condition, our results suggest that easily-obtained measures of human activity are at least as predictive as many of the harder-to-measure biological indicators that have been proposed.  相似文献   

14.
The Mann–Kendall test has been proposed as a nonparametric method to evaluate trends in long-term water quality datasets with missing values, serial correlation, and non-normality. However, this test has rarely been used to evaluate long-term trends in biological data. In this study, we used the Mann–Kendall test to evaluate trends in 15?years of data on benthic macroinvertebrate communities from 17 Precambrian Shield lakes. We also used the van Belle and Hughes test of trend homogeneity to assess whether common among-lake temporal trends existed. We assumed that evidence of a common regional trend among lakes would support the hypothesis of long-term biological recovery from past acidification. We found decreasing proportions of Chironomidae and increasing proportions of Ephemeroptera, Plecoptera, and Trichoptera (EPT) in both single-lake and multi-lake trend analysis. Moreover, six of the nine lakes with significant trends in more than one benthos metric displayed a significant decrease in Chironomidae and increase in EPT concurrently, indicating a shift towards more acid-sensitive taxa. Weak trends in several of the biological metrics indicated that recovery in these lakes has been impeded. Results of this study indicate that the Mann–Kendall and van Belle and Hughes trend tests are useful statistical tools to evaluate long-term patterns in biological data.  相似文献   

15.
Remote sensing has been used from the 1980s to study inland water quality. However, it was not until the beginning of the twenty-first century that CHRIS (an experimental multi-angle sensor with good spectral and spatial resolutions) and MERIS (with good temporal and spectral resolutions) started to acquire imagery with very good resolutions, which allowed to develop a reliable imagery acquisition system so as to consider remote sensing as an inland water management tool. This paper presents the methodology developed, from the field data acquisition with which to build a freshwater spectral library and the study of different atmospheric correction systems for CHRIS mode 2 and MERIS images, to the development of algorithms to determine chlorophyll-a and phycocyanin concentrations and bloom sites. All these algorithms allow determining water eutrophic and ecological states, apart from generating surveillance maps of toxic cyanobacteria with the main objective of Assessment of the Water Quality as it was used for Monitoring Ecological Water Quality in smallest Mediterranean Reservoirs integrated in the Intercalibration Exercise of European Union Water Framework Directive (WFD). We keep on using it to monitor the Ecological Quality Ratio (EQR) in Spain inland water.  相似文献   

16.
A procedure to select the most relevant metrics for assessing the ecological condition of the Douro basin (north Portugal) was developed based upon a set of 184 benthic community metrics. They were grouped into 16 biological categories selected from literature using data collected over 2 years from 54 sites along 31 rivers covering the whole perceived range of human disturbance. Multivariate analyses were carried out to identify the main trends in the macroinvertebrate data, to select reference versus impaired sites, to avoid multicolinearity between metrics, and to identify those that were clearly independent from natural stream typology. Structural metrics, adaptation metrics, and tolerance measures most effectively responded across a range of human influence. We find these attributes to be ecologically sound for monitoring Portugal’s lotic ecosystems and providing information relevant to the Water Framework Directive, which asserts that the definition of water quality depends on its “ecological status”, independent of the actual or potential uses of those waters.  相似文献   

17.
Bioassays as well as biochemical responses (biomarkers) in ecosystems due to environmental stress provide us with signals (environmentally signalling) of potential damage in the environment. If these responses are perceived in this early stage in ecosystems, the eventual damage can be prevented. Once ecosystem damage has occurred, the remedial action processes for recovery could be expensive and pose certain logistical problems. Ideally, “early warning signals” in ecosystems using sensing systems of biochemical responses (biomarkers) would not only tell us the initial levels of damage, but these signals will also provide us with answers by the development of control strategies and precautionary measures in respect to the European Water Framework Directive (WFD). Clear technical guidelines or technical specifications on monitoring are necessary to establish and characterise reference conditions for use in an ecological status classification system for surface water bodies. For the Ecotoxicological Risk Assessment (ERA) of endocrine effects we used an approach of the exposure – dose – response concept. Based on the “Ecototoxicological Classification System of Sediments” that uses pT-values to classify effects in different river systems, we transferred the bio-monitoring data to the five-level ecological system of the WFD. To understand the complexity of the structure of populations and processes behind the health of populations, communities and ecosystems an ERA should establish links between natural factors, chemicals, and biological responses so as to assess causality. So, our ecological monitoring assessment has incorporated exposure & effects data.  相似文献   

18.
After more than a decade from the publication of the European Directive 2001/42/CE (Directive) on Strategic Environmental Assessment (SEA), the design and construction of the interested spatial planning instruments has gone through a variety of changes and integrations in European and in world states. This inhomogeneous panorama can be explained with a pattern of institutional structures that have so far affected the implementation of the Directive. The aim of this paper is to investigate the level of implementation of the Directive in Italy by developing a comparative analysis of the quality of integration of SEA within the design of the spatial coordination plan of a set of Italian provinces. Italian practice is analyzed in the framework of a comparative study of worldwide SEA implementation within spatial and land use planning. The results reveal strengths and weaknesses in SEA implementation at the provincial level and, in particular, the emergence of critical areas of research concerning institutional context, public participation, monitoring, and observatory of the spatial transformations.  相似文献   

19.
20.
This paper concentrates on determining the areas for afforestation and the development of conservation strategies and actions in the case where there is high demand for the conservation of a particular land area. The analysis of hydrological landscape structure and of erodibility was prerequisite in the methodological design considering the site-specific natural landscape characteristics of the study area. The Gölba?? Specially Protected Area (SPA) being the case area has many local environmental disturbances, especially with respect to its hydrological system, and the area is beset by increasing demands for its use by the burgeoning human population. It is obviously clear that the present intensive demand for recreational use will be forecasted further increase in the future. The count of rural residences is estimated to increase by 50% over the next decade. This intensive demand shall further strain the carrying capacity of the ecological milieu, which has already suffered to a significant degree because of the present urban and rural activities. The Gölba?? district is located only 20 km from the city center of Ankara, and its surroundings were legally designated to be a Specially Protected Area primarily for the existence of lacustral and fluvial systems where two interconnected lakes exist: Mogan and E?mir Lakes. Essentially, the continuity of the lacustral and fluvial system of Lakes Mogan and E?mir depends on the preservation and improvement of the water sources. However, interconnected surface water bodies of these lakes are actually quite contaminated, and a decline in the water flow from Mogan to E?mir has been observed. For the elaboration of the present method, required conventional maps (at 1/25,000 scale) of topography (for slope analysis) and geology (for erodibility and permeability analysis) were transferred to computer media using AutoCAD® R.14 software. The rectification of the transferred data was done using ERDAS® Imagine 8.3. All data were then transferred into a GIS engine (Arcview® 3.2). This software provided the ability to create, manipulate, analyze and display topologically correct geographic data in digital form. The method proceeded according to the following phases: 1. Analysis of the hydrologic landscape structure; 2. Permeability of the soil structure; 3. Permeability of the geological structure; 4. Conservation zones.  相似文献   

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