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71.
通过对生态系统健康评价体系的研究,以沙湖为例进行论证,最终得出沙湖生态系统健康度为0.32,属于不健康,制约沙湖不健康的疾病因子在于:湿地的补水水质差,导致湿地水质污染加重,富营养化现象严重,并且由于人为因素,导致物种多样性逐年下降,以上因素最终导致了沙湖湿地生态系统抗干扰能力下降,湖区湿地健康水平较低,根据对沙湖湿地功能的分析,最终设计出了沙湖湿地生态系统健康恢复技术方案。 相似文献
72.
江汉湖群典型湖泊生态系统健康评价——以梁子湖、洪湖、长湖、斧头湖、武湖为例 总被引:1,自引:0,他引:1
湖泊生态系统健康评价对湖泊生态健康状况评定、环境问题诊断和湖泊生态系统管理具有重要意义.根据江汉湖群实际情况和生态特点,选取江汉湖群五大湖泊—梁子湖、长湖、洪湖、斧头湖和武湖为研究对象,采用野外调查、资料收集并结合GIS技术的研究方法,从生物、水质、生境特征及生态压力4个方面选择15个代表性评价指标,构建江汉湖群典型湖泊生态系统健康评价指标体系,并利用基于模糊综合评价模型的评价方法,对江汉湖群五大湖泊生态系统健康进行评价.结果表明,江汉湖群五大湖泊生态健康综合评价得分值为5.47~7.46,梁子湖得分最高,其余依次为斧头湖、洪湖、长湖和武湖.从湖泊生态系统健康等级看,五大湖泊中梁子湖和斧头湖处于比较健康状态,而洪湖、长湖和武湖处于亚健康状态.通过实例分析表明,本研究建立的湖泊生态系统健康评价方法能够较客观系统地评价江汉湖群生态系统健康状况,具有较高的可行性和可靠性,可作为江汉湖群健康诊断的评价方法.本文研究结果可为江汉湖群的分类管理提供较为重要的参考依据. 相似文献
73.
74.
The use of quantitative data for constructing prognostic maps of the dynamics of ecosystem degradation and restoration by
nonlinear simulation methods is a topical field of landscape ecology. This method of dynamic cartography is based on fiberwise
comparison of data on the state of Chernye Zemli (the Kalmyk Republic, Russia) in different years and the detailed analysis
of the period on which the prognosis was based. For this purpose, materials of repeated aerial and satellite photography obtained
during a long period (1954–1993) were used. Comparison of maps characterizing the dynamics of Chernye Zemli between 1958 and
1993 allows prognostic electronic maps for the next 10–15 years (with a five-year interval) to be drawn and land prognosis
for the next 20–30 years (1998–2023) to be obtained.
Deceased 相似文献
75.
利用生物完整性指数评价河流健康状态,对于水环境管理决策具有重要的实践意义。基于大型底栖动物构建生物完整性指数(B-IBI),并评价松花江流域的水生态系统健康状况。在松花江主要干支流设定37个采样点,分别于2016年6、9月进行环境因子和大型底栖动物调查研究。最终从28个候选参数中确定了种类总数、摇蚊种类数、敏感种百分比、Hilsenhoff指数、Marglef指数作为核心参数构建B-IBI。通过0~10赋分法,计算得到了松花江流域全部采样点的生物完整性评价得分。结果显示,松花江流域内60%区域生物状态存在不同程度的损害。另外,B-IBI能够综合反映松花江大型底栖动物群落多样性、生境质量、理化水质等,具有一定的适用性。 相似文献
76.
The ecosystem services (ES) concept is being increasingly incorporated into environmental policy formulation and management approaches. The Corporate Ecosystem Services Review (ESR) is a framework used to assess the dependence and impact that a business has on ES. The success of the corporate experience of ES assessment provides an opportunity for adaption for local authority decision making. In this paper, the ESR tool was adapted to the South African setting at a local government level, and tested at two sites in the Msunduzi Municipality, KwaZulu-Natal. In testing the tool and gathering feedback from key stakeholders, it was found that there are both opportunities and challenges to this approach. Overall, however, it provides an opportunity for the systematic inclusion of ES assessment into existing regulatory frameworks for land-use planning and Integrated Environmental Management, whether in a strategic application, at a broader spatial (municipal) scale or in a specific locale within the municipality. 相似文献
77.
土地利用生态服务价值指标体系评估结果比较研究 总被引:5,自引:0,他引:5
赵小汎 《长江流域资源与环境》2016,25(1):98-105
生态系统服务价值评估越来越受到学术界关注。针对当前生态服务价值评估方法、指标体系和评估效果较多的实践,通过文献归纳,对国内外土地利用生态服务价值评价方法、指标体系及其系数进行了梳理、分类和评价,将指标体系分为Costanza和谢高地两大类,并将谢高地指标体系分为价值当量、价值系数和区域修正。以辽宁省2005、2010年土地利用数据为案例,运用Costanza价值系数、谢高地两个版本价值当量、两个版本价值系数的区域修正,分别核算了案例区生态系统服务价值及变化,并比较评价结果。研究得出Costanza价值系数应用于中国实践时评估结果显得偏低,谢高地2002版的价值当量和2002版的价值系数区域修正结果最接近平均值,相对较为可取,2007版的价值系数区域修正评估结果也较为接近均值但略低,2007版的价值当量评估结果总体偏高。研究结果有利于指导土地利用生态服务价值评估指标体系选取。 相似文献
78.
Elena N. Bukvareva Karsten Grunewald Sergey N. Bobylev Dimitry G. Zamolodchikov Alexey V. Zimenko Olaf Bastian 《Ambio》2015,44(6):491-507
This paper focusses on a conceptual overview of ways to address a comprehensive analysis of ecosystem services (ES) in a country as large and heterogeneous as Russia. As a first step, a methodology for assessing the services for the federal subjects of Russia was chosen, i.e., its constituent provinces and similar entities, in physical terms. Russia harbors a great diversity of natural conditions and ecosystems which are suppliers of ES, and likewise a variety of the socio-economic conditions that shape the demand for these services and their consumption. The methodological approach described permits several important tasks to be addressed: the evaluation of the degree of satisfaction of people’s needs for ES, the identification of ecological donor and acceptor regions, and zoning of the country’s territory for ES assessment. The next step is to prepare a prototype of a National Report on ES in Russia, for which we are presenting the planned structure. 相似文献
79.
Measurement and Management of Human-Induced Patterns of Forest Fragmentation: A Case Study 总被引:1,自引:0,他引:1
Tole L 《Environmental management》2006,37(6):788-801
In many tropical developing countries, the twin pressures of population and poverty are resulting in substantial fragmentation
of forests, increasing the probability of extinction for many species, Forest fragmentation occurs when large contiguous forests
are perforated by small holes or broken up into edges and smaller patches to form a nonforested matrix of open spaces. Thus,
forest fragmentation refers not only to the area of forest cleared, but also to the pattern of this clearance, the resulting
forest’s spatial properties. Both characteristics are important for species survivability. Apart from opening up forests to
many abiotic and biotic influences, fragmentation can affect species dispersal and migration through its effects on forest
connectivity. Landscape ecology conceptualizes connectivity as a gradient of critical thresholds, ranging from the large intact
forest to the small unconnected forest patch. This article reports results from a multiple-scale analysis of forest fragmentation
in Jamaica’s Cockpit Country, an area of once contiguous forest now under threat from human encroachment. Spatial forest data
derived from classification of ETM+ satellite imagery are used to measure fragmentation patterns representing various degrees
of forest connectivity and density. The results suggest that, overall, 81% of the region is in forest. However, fragmentation
patterns also suggest that this forest is riven with extensive perforations indicative of an early stage in the decline of
contiguity. The results provided by the spatial fragmentation model are a first step in the design of effective conservation
and rehabilitation plans for the area. The article concludes with a discussion of possible multiscale management options for
the region. 相似文献
80.
Tarsitano E 《Environmental management》2006,38(5):799-809
In urban ecosystems, the ecological system has become completely unbalanced; this, in turn, has led to an increase in well-known
problems such as air pollution, ground pollution, and water pollution. This imbalance has also led to the growth and spread
of pathogens harmful to man, animals, and plants. Urban sustainability indicators, both global and local, also “indicate”
the percentage of population, but these refer only to the human population, not the animal population. Cities need good waste,
water, and air management, effective traffic planning, and good zoning of businesses, crafts, and services; over and above
these activities, cities also need for planning to take into account the existence of pets (dogs, cats, and etc.) and nonpet
animals (insects, birds, mice, etc.). Cities tend to be designed around humans and “on a human scale,” without taking into
account the fact that a huge animal population is living side by side with people. That explains why overcrowding tends to
go hand in hand with urbanization; all these populations, including humans, need to adapt to new spaces and often need to
drastically change their behavior. This is a fact that must be included when drafting sustainable city plans. The supposed
strategy is that of “integrated-participatory” control of the interactions between the environment and animals in the cities.
Strategy will focus on the development of integrated approaches and tools for environment and animal management in the context
of urban settings. This will require such specific methods as ecological balance sheets and ecoplans for the planning, management,
and control of the interrelation among environment, animal, and public health. The objective is to develop a better understanding
of urban biodiversity and of urban ecosystem functioning, in order to understand and minimize the negative impacts of human
activities on them. The research will focus on assessing and forecasting changes in urban biodiversity, structure, function,
and dynamics of urban ecosystems, with relationships among society, economy, biodiversity, and habitats. 相似文献