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1.
The destruction of coral reef habitats has occurred at unprecedented levels during the last three decades. Coral disease and bleaching in the Caribbean and South Florida have caused extensive coral mortality with limited recovery, often coral reefs are being replaced with turf algae. Acroporids were once dominant corals and have diminished to the state where they are being considered as endangered species. Our survey assessed the condition of reef corals throughout South Florida. A probability-based design produced unbiased estimates of the spatial extent of ecological condition, measured as the absence or presence and frequency or prevalence of coral diseases and bleaching intensity over large geographic regions. This approach allowed us to calculate a quantifiable level of uncertainty. Coral condition was estimated for 4100 hectares (ha) (or 41.0 km2) of coral reefs in South Florida, including reefs in the Florida Keys National Marine Sanctuary (FKNMS), New Grounds, Dry Tortugas National Park (DTNP), and Biscayne National Park (BNP). The absence or presence of coral disease, causal coral bleaching, partial bleaching and coral paling were not good indicators of overall coral condition. It was more useful to report the prevalence of anomalies that indicated a compromised condition at both the population and community levels. For example, 79% of the area in South Florida had less than 6% of the coral colonies diseased, whereas only 2.2% (97.15 ha) of the sampled area had a maximum prevalence of 13% diseased coral colonies at any single location. The usefulness of causal bleaching might be more important when considering the prevalence of each of the three different states at a single location. For example, paling was observed over the entire area, whereas bleaching and partial bleaching occurred at 19 and 41% of the area, respectively. An index for coral reef condition might integrate the prevalence and species affected by each bleaching state at individual locations. By establishing these baselines, future surveys can examine changes and trends in the spatial distribution of coral conditions in South Florida and able to score the reefs as to their health status.  相似文献   

2.
生态监测指标选择一般过程探讨   总被引:8,自引:2,他引:8  
本文对生态监测指标体系设计的一般过程进行了详细的分析和论述。主要包括生态监测目标、生态系统所受的环境压力、生态系统模型的提出以及生态监测指标的分类。旨在为我国生态监测规划和设计进行初步的探索。  相似文献   

3.
The Landscape Development Intensity index (LDI), which is based on non-renewable energy use and integrates diverse land use activities, was compared to other measures of LU (e.g., %agriculture, %urban) to determine its ability for predicting benthic diatom composition in freshwater marshes of peninsular Florida. In this study, 70 small, isolated herbaceous marshes located along a human disturbance gradient (generally agricultural) throughout peninsular Florida were sampled for benthic diatoms and soil and water physical/chemical parameters (i.e., TP, TKN, pH, specific conductance, etc.). Landscape measures of percent agriculture, percent urban, percent natural, and LDI index values were calculated for a 100 m buffer around each site. The strongest relationships using Mantel's r statistic, which ranges from −1 to 1, were found between benthic diatom composition, the combined soil and water variables, and LDI scores (r=0.51, P<0.0001). Although similar, soil and water variables alone (r=0.45, P<0.0001) or with percent agriculture or percent natural were not as strongly correlated (both Mantel's r=0.46, P<0.0001). Little urban land use was found in the areas surrounding the study wetlands. Diatom data were clustered using flexible beta into 2 groups, and stepwise discriminant analysis identified specific conductance, followed by LDI score, soil pH, water total phosphorus, and ammonia, as cluster-separating variables. The LDI explained slightly more of the variation in species composition than either percent agriculture or percent natural, perhaps because the LDI can combine disparate land uses into a single quantitative value. However, the ecological significance of the difference between land use metrics and diatom composition is controvertible, and additional tests including more varied land uses appear warranted.  相似文献   

4.
We describe a study designed to evaluate the performance ofwetland condition indicators of the Prairie Pothole Region (PPR)of the north central United States. Basin and landscape scaleindicators were tested in 1992 and 1993 to determine theirability to discriminate between the influences of grasslanddominated and cropland dominated landscapes in the PPR. Pairedplots were selected from each of the major regions of the PPR.Among the landscape scale indicators tested, those most capableof distinguishing between the two landscapes were: 1) frequencyof drained wetland basins, 2) total length of drainage ditch perplot, 3) amount of exposed soil in the upland subject to erosion,4) indices of change in area of wetland covered by water, and5) number of breeding duck pairs. Basin scale indicators includingsoil phosphorus concentrations and invertebrate taxa richnessshowed some promise; however, plant species richness was the onlystatistically significant basin scale indicator distinguishinggrassland dominated from cropland dominated landscapes. Althoughour study found a number of promising candidate indicators, oneof our conclusions is that basin scale indicators present anumber of implementation problems, including: skill levelrequirements, site access denials, and recession of site accessby landowners. Alternatively, we suggest that the use oflandscape indicators based on remote sensing can be an effectivemeans of assessing wetland integrity.  相似文献   

5.
水生态完整性评价通过对水生态系统中不同生态组分(非生物和生物)的监测,整合物理栖息地、环境水质和生物特征形成综合评价指数来反映水生态系统健康状况,是流域水环境管理的重要手段。笔者尝试从水生态完整性评价中基准与参照状态的核心要素出发,探讨基准与参照状态的概念框架与具体定义,综述评价参照状态的四大类确定方法(基于分类学的参照位点法、历史数据法,针对特定位点的模型预测法以及提供经验解释与描述的专家判断法),并对参照状态研究的挑战与应用予以展望。  相似文献   

6.
Monitoring of indicators of the ecological condition of bays, tidal rivers, and estuaries within the Virginian Biogeographic Province (Cape Cod, Massachusetts to Cape Henry, Virginia) was conducted annually by the U.S. EPA's Environmental Monitoring and Assessment Program (EMAP) during the summer months of 1990 to 1993. Data were collected at 425 probability-based stations within the Province. Indicators monitored included water quality (temperature, salinity, water clarity, and dissolved oxygen concentration), sediment contamination, sediment toxicity, benthic community structure, fish community structure, and fish gross external pathology. Data were used to estimate the current status of the ecological condition of Virginian Province estuarine resources, and provide a baseline for identifying possible future changes. Estimates, with 95% confidence limits, of the areal extent of impacted resources within the Province are provided. Data are also presented by estuarine class (large estuaries, small estuarine systems, and large tidal rivers). Results show that, overall, approximately half of the estuarine waters of the Virginian Province can be classified as impacted based on multiple indicators, with hypoxia being the major stressor.  相似文献   

7.
周刚 《干旱环境监测》2003,17(2):93-95,116
主要从生态恢复方面对甘家湖荒漠林区的恢复措施及其所产生的环境效益、社会效益及综合效应进行论证,分析甘家湖荒漠林区目前的状况及采取恢复措施后所能达到的效果。  相似文献   

8.
This paper presents the results of research which evaluated the performance of strategic environmental assessment (SEA) practice in South Africa in order to develop understanding of how SEA functions within a developing country with a voluntary SEA system. The research applied a combination of methods in a mixed research strategy, including a macro level survey of the SEA system together with case study reviews exploring micro level application. Three main ‘system features’ emerged, namely expansion of voluntary practice, diversity in practice and general ineffectiveness. The results also highlight a number of ‘application features’ such as a lack of focus due to an inability to deal with the concepts of ‘sustainability’ and ‘significance’, as well as poor understanding and integration with decision-making processes. Moreover, it emerged that none of the case studies seem to have conducted an ‘assessment’ per se, but rather provided a framework for strategic decision-making. The paper puts forward a number of interrelated explanations for these system and application features. In a parallel to the fable of the ‘emperor's new clothes’, SEA in South Africa appears to be regarded as the answer to all environmental problems, whilst being ineffective in practice.  相似文献   

9.
In 1999, the United States Environmental Protection Agency Gulf Ecology Division initiated a pilot study to assess the condition of nearshore coastal resources. Near-shelf areas associated with coastal beaches are susceptible to land based activities, but are not consistently monitored. Additionally, few or no marine water quality criteria exist for evaluating these waters. The goal of this pilot study was to assess the ecological condition of Gulf of Mexico near-shelf resources using a probability-based survey design. Data are used to generate a baseline assessment of condition in coastal nearshore areas and provide a comparative tool for evaluating future trends in condition. Water quality, sediment quality and benthic diversity data can provide a baseline assessment for managers to evaluate the potential for future problems such as nutrient over-enrichment, sediment contamination and degraded biological condition. We present results from a probability-based survey demonstration assessing near-shelf resources along the Florida panhandle.  相似文献   

10.
对泰山区目前水环境监测网络系统进行了综合分析评价 ,采用专家权重评估、物元分析方法对原监测断面进行了优化研究 ,在此基础上建立起新型监测网络的地理信息系统  相似文献   

11.
Environmental benchmarks are widely used in Canadian environmental assessment as a standard against which to monitor air or water quality in response to human activities in the environment. Recent work in Canada has developed the concept of ecological benchmarks as a complement to environmental benchmarks. However, implementation of ecological benchmarks may be challenging. This paper presents an analogy between ecological benchmarks and the more commonly used environmental benchmarks, as an attempt to increase understanding and use of ecological benchmarks in resource management, assessment, and monitoring. Ecological benchmarks, and their corresponding indicators, will be challenging to identify and use. However, through the use of the principles of adaptive management, effective ecological indicators and benchmarks can be established. Although it is essential that ecological benchmarks are site-specific, the analogy and general principles outlined here are applicable to assessment and monitoring in any part of the world.  相似文献   

12.
基于环境一号卫星CCD传感器性能,从生态景观角度入手,针对江苏省地形地貌特征,开展了环境一号卫星CCD数据在生态环境监测和评价工作中的应用可行性研究,结果表明环境一号卫星CCD数据可以满足江苏省生态环境监测和评价工作需要,其时间分辨率和幅宽是开展生态监控和预警的重要优势。  相似文献   

13.
Sustainable development or sustainability has been highlighted as an essential principle in urban master planning, with increasing recognition that uncontrollable urbanization may well give rise to various issues such as overexploitation of natural resources, ecosystem destruction, environmental pollution and large-scale climate change. Thus, it is deemed necessary to modify the existing urban and regional administrative system so as to cope with the challenges urban planning is being confronted with and realize the purpose of urban sustainability. This paper contributed to proposing a mechanism which helps to make urban planning with full consideration of issues with respect to sustainable development. We suggested that the integration of urban planning, SEA and ecological planning be a multi-win strategy to offset deficiency of each mentioned political tool being individually applied. We also proposed a framework where SEA and ecological planning are fully incorporated into urban planning, which forms a two-way constraint mechanism to ascertain environmental quality of urban planning, although in practice, planning and SEA processes may conditionally be unified. Moreover, as shown in the case study, the integration of the three political tools may be constrained due to slow changes in the contextual factors, in particular the political and cultural dimensions. Currently within the context of China, there may be three major elements which facilitate integration of the three political tools, which are (1) regulatory requirement of PEIA on urban planning, (2) the promotion or strong administrative support from government on eco-district building, and (3) the willingness of urban planners to collaborate with SEA experts or ecologists.  相似文献   

14.
我国城市声环境质量状况与分析   总被引:8,自引:2,他引:8  
介绍了我国城市声环境质量状况,并就相关问题进行了分析.我国城市道路交通声环境质量大部分处于好和较好水平;城市区域声环境质量主要处于较好和轻度污染状态;约有1%的人口处在噪声重度污染区域;交通噪声影响强度最大;社会生活噪声影响范围最广;环境噪声污染仍存在污染投诉率高、交通噪声污染严重等问题,改善声环境质量仍是今后一项主要工作.  相似文献   

15.
The paper draws results from a review of literature to examine the strengths and weaknesses of the integrated environmental assessment framework in Canada with respect to the inclusion of health impact assessment. Insights include the legislative nature, rigid structure and priority for the natural environment that may restrict progress and the pool of government agencies that need to be convinced of the benefits of health impact assessment that may provide a strong structure for compliance in the long term.  相似文献   

16.
生物多样性是环境监测环境保护的重要内容之一,在众多的生物多样性指数中,包含分类学信息的指数具有明显的特点和优势。近20年来,在海洋、淡水、陆地等生境中开展了许多分类学多样性指数相关的应用研究。一些分类学多样性指数能够在一定程度上灵敏地反映出环境退化和污染,在环境监测能力和历史资料对比等方面优于传统多样性指数。在使用分类学差异性指数区分人类干扰和自然变化时结论不一,分类学多样性指数的应用受到一些因素的影响,例如生物类群选择、生境、水深、纬度等是产生分歧的因素。扩大研究范围,明确应用范围可有效发挥分类学差异性指数在环境保护和评价中的作用。  相似文献   

17.
乌鲁木齐市郊安宁渠区土壤重金属的污染调查   总被引:5,自引:0,他引:5  
胡慧玲 《干旱环境监测》2003,17(2):117-119,122
对乌鲁木齐产莱区安宁渠区的表层土壤及地表下40cm土壤中重金屑Cd、Hg、As、Pb、Cr进行了分析和测定,并对土壤中的重金属污染进行了环境质量评价。结果表明,安宁渠区土壤大部分为轻污染,但个别点已达重度污染,地表的污染较地表下40cm土壤为重。污染为外源性污染,与垃圾肥料的使用有关。  相似文献   

18.
环评报告是建设项目开展环保验收工作的重要依据。环保验收工作中必须对照环评报告的内容及要求进行调查和监测。由于环评报告中工程内容、环保措施、评价因子等内容不够完善,使得工程建设中措施无法完全落实,造成环保验收工作不能顺利进行。本文通过对环保验收监测中遇到的实例进行分析,为更好的开展环评及验收监测工作提供建议。  相似文献   

19.
扎龙湿地的生态环境评价及防治对策   总被引:9,自引:0,他引:9  
介绍了扎龙湿地的生态状况 ,并运用模糊数学对其生态状况给予评价 ,为做好扎龙湿地的生态保护工作 ,提出了相应的对策  相似文献   

20.
简述了环境影响评价中公众参与的定义、目的、意义,简要回顾了国内外环境管理及环境影响评价中公众参与的发生发展过程及其现状,浅析了公众参与在环境影响评价中的应用以及存在的问题,并提出了改进的建议。  相似文献   

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