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湖泊健康评价指标体系及评价方法初探   总被引:2,自引:0,他引:2  
李灿  李永  李嘉 《四川环境》2011,30(2):71-75
湖泊健康评价是进行湖泊监测和管理的基础。丰富了湖泊生态系统健康的概念,指出其应当考虑湖泊的各种服务功能。以湖泊生态系统健康概念为基础,构建了湖泊健康评价指标体系,给出16个综合评价指标及各指标评分方法。以四川大学明远湖为例,采用层次分析法(AHP)计算各指标权重,对其进行健康评价,得出健康综合指数为3.55,表明整个湖泊处于"较健康"状态,分析了影响湖泊健康状态的疾病因子及湖泊的生态修复方法。  相似文献   

3.
Habitat Assessment of Non-Wadeable Rivers in Michigan   总被引:1,自引:0,他引:1  
Habitat evaluation of wadeable streams based on accepted protocols provides a rapid and widely used adjunct to biological assessment. However, little effort has been devoted to habitat evaluation in non-wadeable rivers, where it is likely that protocols will differ and field logistics will be more challenging. We developed and tested a non-wadeable habitat index (NWHI) for rivers of Michigan, where non-wadeable rivers were defined as those of order ≥5, drainage area ≥1600 km2, mainstem lengths ≥100 km, and mean annual discharge ≥15 m3/s. This identified 22 candidate rivers that ranged in length from 103 to 825 km and in drainage area from 1620 to 16,860 km2. We measured 171 individual habitat variables over 2-km reaches at 35 locations on 14 rivers during 2000–2002, where mean wetted width was found to range from 32 to 185 m and mean thalweg depth from 0.8 to 8.3 m. We used correlation and principal components analysis to reduce the number of variables, and examined the spatial pattern of retained variables to exclude any that appeared to reflect spatial location rather than reach condition, resulting in 12 variables to be considered in the habitat index. The proposed NWHI included seven variables: riparian width, large woody debris, aquatic vegetation, bottom deposition, bank stability, thalweg substrate, and off-channel habitat. These variables were included because of their statistical association with independently derived measures of human disturbance in the riparian zone and the catchment, and because they are considered important in other habitat protocols or to the ecology of large rivers. Five variables were excluded because they were primarily related to river size rather than anthropogenic disturbance. This index correlated strongly with indices of disturbance based on the riparian (adjusted R2 = 0.62) and the catchment (adjusted R2 = 0.50), and distinguished the 35 river reaches into the categories of poor (2), fair (19), good (13), and excellent (1). Habitat variables retained in the NWHI differ from several used in wadeable streams, and place greater emphasis on known characteristic features of larger rivers.  相似文献   

4.
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   

5.
Continued resource degradation in various areas of the Great Lakes has led to doubts of the adequacy of conventional science and management approaches. The need for a more holistic approach, identified as an ecosystem approach, appears now to be more widely accepted although progress with implementation is slow. We argue here that ecosystem science is an integral part of an ecosystem approach and is a prerequisite to effective management planning.One of the problems of implementing an ecosystem approach is forging the link between ecosystem based research and management. For Green Bay, Wisconsin, USA, certain structural and functional qualities of the ecosystem have been used to define operational guides and to formulate management objectives. These objectives are being utilized in the development of a remedial action plan for Green Bay.Deceased 5 February 1986.  相似文献   

6.
Regionalization frameworks cluster geographic data to create contiguous regions of similar climate, geology and hydrology by delineating land into discrete regions, such as ecoregions or watersheds, often at several spatial scales. Although most regionalization schemes were not originally designed for aquatic ecosystem classification or management, they are often used for such purposes, with surprisingly few explicit tests of the relative ability of different regionalization frameworks to group lakes for water quality monitoring and assessment. We examined which of 11 different lake grouping schemes at two spatial scales best captures the maximum amount of variation in water quality among regions for total nutrients, water clarity, chlorophyll, overall trophic state, and alkalinity in 479 lakes in Michigan (USA). We conducted analyses on two data sets: one that included all lakes and one that included only minimally disturbed lakes. Using hierarchical linear models that partitioned total variance into within-region and among-region components, we found that ecological drainage units and 8-digit hydrologic units most consistently captured among-region heterogeneity at their respective spatial scales using all lakes (variation among lake groups = 3% to 50% and 12% to 52%, respectively). However, regionalization schemes capture less among-region variance for minimally disturbed lakes. Diagnostics of spatial autocorrelation provided insight into the relative performance of regionalization frameworks but also demonstrated that region size is only partly responsible for capturing variation among lakes. These results suggest that regionalization schemes can provide useful frameworks for lake water quality assessment and monitoring but that we must identify the appropriate spatial scale for the questions being asked, the type of management applied, and the metrics being assessed.  相似文献   

7.
Shorebird researchers and land managers recognize human disturbance as a serious threat facing shorebirds. Yet, a common understanding of what defines human disturbance is lacking. To address this issue, we employed the Delphi technique, an iterative consensus-building social science method, to bring scientists and managers together to develop a shared definition of human disturbance and a list of priority human activities that could affect migratory shorebirds. During four iterative rounds, participants with extensive knowledge on human disturbance to shorebirds from varying geographic locations within the Northeastern U.S. worked together to produce a shared understanding. Through analyzing participants’ open-ended responses, we identified important themes for the definition. The participants then refined and ranked these themes through surveys, and the top-ranked themes were used to draft a final definition also reviewed by the participants. Participants provided 94 human activities in response to our request to list and describe all potential human disturbances that affect shorebirds during fall migration. From there, we grouped the activities into 23 categories. Through rating and ranking tasks, participants reduced this list to 12 priority disturbance categories that represent the perceived most significant human disturbances in the Northeastern United States. We also compared responses among the different participant groups (i.e., managers, scientists, and manager/scientists), finding that groups’ responses generally did not significantly differ. While nearly all participants were satisfied with the process, we provide some suggestions to improve it. The outputs of the Delphi technique have informed a best practices guidance document for shorebird management.  相似文献   

8.
Ecological disturbances of forests by insects have a complex array of associated human dimensions presenting complications for natural resource decision making and relationships between stakeholders and managers. This article discusses the human context of forest disturbances by insects by reviewing four cases of bark beetle forest disturbance from British Columbia in Canada, Bavarian Forest National Park in Germany, the Kenai Peninsula in Alaska, and the north central region of Colorado. Findings and lessons learned from these studies are outlined along with their implications for managing forest disturbances by insects in general. Conclusions focus on the need to assess the broad array of impacts and risks perceived by local residents and the capacity for local action and involvement in managing forest disturbances. Communication and interaction between resource managers and local stakeholders can facilitate the identification of management priorities and potentially reduce some of the risks associated with forest disturbances by insects.  相似文献   

9.
An optical plankton counter (OPC) potentially provides an assessment tool for zooplankton condition in ecosystems that is rapid, economical, and spatially extensive. We collected zooplankton data with an OPC in 20 near-shore regions of 4 of the Laurentian Great Lakes. The zooplankton size information was used to compute mean size, biomass density, and size-spectra parameters for each location. The resulting metrics were analyzed for their ability to discriminate among the Great Lakes. Biomass density provided discrimination among lakes, as did several parameters describing spectra shape and distribution. A proposed zooplankton indicator, mean size (determined with OPC measurements in this study), was found to provide discrimination among lakes. Size-spectra-related parameters added increased ability to discriminate in conjunction with the biomass density (or mean size) metric. A discriminant function analysis of the multiple metrics (mean size, biomass density, and distribution parameters) suggests that a multi metric size-based approach might be used to classify communities among lakes improving a mean-size metric. The feasibility OPCs and size-based metrics for zooplankton assessment was found to have potential for further development as assessment tools for the biological condition of zooplankton communities in the Great Lakes.  相似文献   

10.
The Great Lakes watershed is home to over 40 million people (Canadian and U.S.) who depend on a healthy Great Lakes ecosystem for economic, societal, and personal vitality. The challenge to policymakers and the public is to balance economic benefits with the need to conserve and replenish regional natural resources in a manner that ensures long term prosperity. Nine critical broad-spectrum stressors of ecological services are identified, which include pollution and contamination, agricultural erosion, non-native species, degraded recreational resources, loss of wetlands habitat, climate change, risk of clean water shortage, vanishing sand dunes, and population overcrowding. Many of these stressors overlap. For example, mining activities alone can create stress in at least five of these categories. The focus groups were conducted to examine the public’s awareness of, concern with, and willingness to expend resources on these stressors. This helped generate a grouping of stressors that the public is especially concerned about, those they care little about, and everything else in between. Stressors that the respondents have direct contact with tend to be the most important to them. This approach of using focus groups is a critical first step in helping natural resource managers such as Trustees and NGOs understand what subsequent steps to take and develop policy measures that are of most interest and value to the public. Skipping or glossing over this key first task could lead to difficulties with respect to survey design and model development in a non-market valuation study. The focus group results show that concern related to pollution and contamination is much higher than for any of the others. It is thus clear that outreach programs may be necessary to educate the public about the severity of some low-ranked stressors including climate change.  相似文献   

11.
A Disturbance Index for Karst Environments   总被引:13,自引:0,他引:13  
Karst environments, unique from other environments, require their own disturbance index. Karst resources are increasingly disturbed by a variety of processes related to social, physical, and economic factors. Recent studies have begun to qualify and quantify these disturbances, yet their focus has been limited to one or two factors such as biotic, geomorphic, or economic impacts. A more holistic approach, addressing economic, scientific, and cultural factors, is needed, to effectively assess the threats to karst areas. Currently, there is no efficient method to measure, compare, and contrast the disturbance of karst environments. We propose a hierarchal and standardized environmental disturbance index as a tool to measure regional impacts and highlight the areas of the karst system that require more protection or study. Addressed categories of disturbance include cultural, biotic, atmospheric, hydrological, and geomorphologic impacts.  相似文献   

12.
Ecosystem‐based management of the Laurentian Great Lakes, which spans both the United States and Canada, is hampered by the lack of consistent binational watersheds for the entire Basin. Using comparable data sources and consistent methods, we developed spatially equivalent watershed boundaries for the binational extent of the Basin to create the Great Lakes Hydrography Dataset (GLHD). The GLHD consists of 5,589 watersheds for the entire Basin, covering a total area of approximately 547,967 km2, or about twice the 247,003 km2 surface water area of the Great Lakes. The GLHD improves upon existing watershed efforts by delineating watersheds for the entire Basin using consistent methods; enhancing the precision of watershed delineation using recently developed flow direction grids that have been hydrologically enforced and vetted by provincial and federal water resource agencies; and increasing the accuracy of watershed boundaries by enforcing embayments, delineating watersheds on islands, and delineating watersheds for all tributaries draining to connecting channels. In addition, the GLHD is packaged in a publically available geodatabase that includes synthetic stream networks, reach catchments, watershed boundaries, a broad set of attribute data for each tributary, and metadata documenting methodology. The GLHD provides a common set of watersheds and associated hydrography data for the Basin that will enhance binational efforts to protect and restore the Great Lakes.  相似文献   

13.
Visual‐based rapid assessment techniques provide an efficient method for characterizing the restoration potential of streams, with many focusing on channel stability and instream habitat features. Few studies, however, have compared these techniques to see if they result in differing restoration priorities. Three rapid assessment techniques were contrasted at three wild trout streams in western New York with different amounts of channel disturbance. Two methods focused only on geomorphic stability, whereas the third addressed physical habitat condition. Habitat assessment scores were not correlated with scores for either geomorphic assessment method and they varied more between channels with different degrees of disturbance. A model based on dynamic equilibrium concepts best explains the variation among the streams and techniques because it accounts for a stream's capacity to maintain ecological integrity despite some inherent instability. Geomorphic indices can serve as effective proxies for biological indices in highly disturbed systems. Yet, this may not be the case in less disturbed systems, where geomorphic indices cannot differentiate channel adjustments that impact biota from those that do not. Dynamically stable streams can include both stable and unstable reaches locally as characterized by geomorphic methods and translating these results into restoration priorities may not be appropriate if interpretations are limited to the reach scale.  相似文献   

14.
The Northern Michigan Environmental Research Program was conducted by the University of Michigan's Biological Station and Institute for Social Research to obtain information about the aquatic and human resources of water-rich, resort-oriented northern lower Michigan. Results of the study were directed toward long-term environmental management. Multiple methods were used to communicate study results, including self-contained information briefs, regular contacts and seminars with community leaders and public officials, and mass media. Selected illustrations of project data applied to environmental management problems are cited, e.g., curtailment of nutrient loadings, wetlands protection, improved effectiveness of riparian organizations, and highway planning. A series of shortLakeland Reports, designed to present factual information, general environmental principles, and action implications to a lay audience, proved to be effective. However, it became apparent that environmental decisions were not strongly affected by reports alone. Instead, several mutually reinforcing channels of communication must be employed to develop a climate of receptiveness and understanding to insure environmentally sound decisions.  相似文献   

15.
本文在对现有住区人居环境评估体系、现代住宅小区人居环境适宜性的含义和特点做出具体分析的前提下,将自然生态、人文生态分为三个层次共计二十六项指标建立了住宅小区人居环境适宜性综合评价指标体系,并运用权重计算方法对实例进行了分析说明,为住宅小区人居环境适宜性问题的进一步研究提供了基础。  相似文献   

16.
/ One attempt to quantify targets for rehabilitating degraded aquatic ecosystems has been through a United States-Canada program to develop and implement comprehensive remedial action plans (RAPs) to restore beneficial uses in 42 Great Lakes Areas of Concern. The International Joint Commission has facilitated agreement on listing/delisting guidelines for determining when use impairments exist in areas of concern and when uses have been restored, while federal/state/provincial governments and local stakeholders have provided leadership in establishing quantitative targets for restoring uses and in determining how to achieve them. The listing/delisting guidelines have been instrumental in helping reach agreement on problem definition (lack of agreement on problem definition has historically been used as a reason to delay action) and reaching agreement on quantitative targets for restoring uses. Quantitative, ecosystem-based targets are being used to drive the RAP process, help organizations pursue a common mission of restoring uses, and help achieve greater accountability. As a priority, the target-setting process must also recognize the importance of establishing both short- and long-term milestones in order to measure and celebrate incremental progress in restoring uses.KEY WORDS: Use impairments; Restoring uses; Quantitative targets  相似文献   

17.
论云南高原湖泊环境整治与湖泊旅游开发的互动机制   总被引:2,自引:0,他引:2  
湖泊以其独特的旅游资源成了具有很大吸引力的旅游目的地。高原湖泊成为云南省旅游开发的热点,但是日益严重的湖泊生态环境问题成为制约湖泊旅游开发的瓶颈。文章探讨了湖泊生态环境整治与旅游活动开发的互动机制,并提出了一系列促进二者良性互动的对策与措施,将有利于云南高原湖泊旅游的可持续发展。  相似文献   

18.
A Proposed Aquatic Plant Community Biotic Index for Wisconsin Lakes   总被引:2,自引:0,他引:2  
The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments, Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially have low nutrient levels.  相似文献   

19.
从人地关系的角度出发,构建自然-社会系统指标体系,对2000年、2005年、2007年和2010年长三角25座中心城市人居环境质量进行综合评价,并对人-地关系协调度进行分析,得出以下结论:①自然系统得分差异相对较小,社会系统得分差异相对较大;②自然系统的稳定态减轻了社会系统的差异特征,使综合得分差异相对缩小,但仍然较大;③大部分城市人居环境质量处于一般协调,人-地协调度呈“橄榄状”分布;④人居环境质量得分呈现等级性特征,上海、杭州、南京等城市的人居环境质量较高,而宿迁、淮安等城市的人居环境质量排名靠后.  相似文献   

20.
Regional Representativeness of Swedish Reference Lakes   总被引:1,自引:1,他引:0  
/ Recent focus has been placed on ecoregion delineations for providing an appropriate framework for monitoring and assessment of region-specific attainable water/habitat quality. Using an ecoregion approach to stratify variance, this study was conducted to determine whether earlier (subjectively) selected Swedish reference lakes may be considered as regionally representative reference sites when compared with a randomly selected lake population. Predictive modeling by discriminant function analysis with lakes classified by ecoregion and lake surface area and six physicochemical variables showed that the greater majority of reference lakes may be considered as regionally representative. The highest proportion of lake "misclassifications" occurred in the boreonemoral ecoregion, a relatively diverse ecoregion of southern Sweden. This apparent bias may be in part be due to the criteria used in selecting regional reference lakes. In the earlier selection of reference lakes emphasis was placed on lakes not being adversely affected by land usage or pollutant discharges, consequently forest lakes were often overrepresented and sites in agricultural areas underrepresented in the selected reference sites. As a complement to predictive modeling, PCA ordination showed the placement of reference lakes within the random lake population and indicated where reference sites might be missing along potentially important ecological gradients. KEY WORDS: Regionalization; Ecoregion; Representativeness; Reference; Ordination; Modeling; Temperate lakes  相似文献   

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