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41.
Environmental pollution and degradation of ecosystems considerably affect the natural resources. The Turkish Government is aware of the importance of the preservation of natural ecology and thereby the environmental conservation of many species in their natural habitat. This paper provides critical assessments of the problems and possible solutions in the identification, implementation and management of the Specially Protected Areas (SPAs) system by giving basic information about stakeholders and their responsibilities that currently offer nature conservation in Turkey. The goals of the article are to analyze how the SPAs interface with the local people, especially the villagers who have dwelt there before SPA designation and how people-SPA conflicts resolved; to show how effective the SPA conservation objectives have been; to outline the significance of informing and empowering people in nature conservation for the protected area management and to show the importance of planning at all levels during protection of the natural, archeological and cultural values of the SPAs.  相似文献   
42.
This paper explores some ways in which differing views about the human–nature relationship reflect and are reflected in people's experiences of the places and environments they encounter in their lives. I first describe how ideas of humans being “part of” versus “apart from” nature have appeared in discussions of environmental ethics and management, and suggest how these contrasting views might relate to people's actual experiences of the natural and human aspects of places. Using qualitative survey responses about outdoor places in the midwestern USA to illustrate ideas from phenomenological and gestalt psychology, I show how a sense of the human–nature relationship is conveyed in the gestalt qualities of places and how this may give rise to a feeling of moral responsibility toward nature. I conclude that the experience of human and natural aspects of real places points toward a dialectical view of the human–nature relationship, in which humans can be seen as simultaneously “part of” and “apart from” nature.  相似文献   
43.
通过对雾灵山国家级自然保护区的调查,研究保护区的生态沿革,分析保护区的生态功能、生态作用等生态效应,针对当前所存在的草甸严重退化、动物种群密度降低、水量减少等生态问题,提出对保护区的生态环境应尽快制定环境保护规范化,建立生物多样性保护权威机构,实行社区共管,开展科学生态旅游等措施。  相似文献   
44.
The Sands of Forvie, National Nature Reserve, Scotland is a complex coastal sand dune system which is associated with the dynamic estuary of the River Ythan. The dune system has developed over more than 5000 years. The south part is a peninsula of dunes, sand hills, sand arcs, erosion and deflation surfaces. The north part is superimposed on a rock plateau with a cliff coastline. This plateau is covered in glacial deposits and is essentially an upland heath landscape. Some of the best examples of large active parabolic dunes in Britain are found in North Forvie. The sequence of geomorphic development is described. As a nature reserve with a rich ecology it has been managed for conservational purposes since 1960s. As such it is an excellent case study of how conservational management has changed to become more flexible and more aware of the importance of dynamic processes.  相似文献   
45.
Abstract:  Conservation easements are one of the primary tools for conserving biodiversity on private land. Despite their increasing use, little quantitative data are available on what species and habitats conservation easements aim to protect, how much structural development they allow, or what types of land use they commonly permit. To address these knowledge gaps, we surveyed staff responsible for 119 conservation easements established by the largest nonprofit easement holder, The Nature Conservancy, between 1985 and 2004. Most easements (80%) aimed to provide core habitat to protect species or communities on-site, and nearly all were designed to reduce development. Conservation easements also allowed for a wide range of private uses, which may result in additional fragmentation and habitat disturbance. Some residential or commercial use, new structures, or subdivision of the property were permitted on 85% of sampled conservation easements. Over half (56%) allowed some additional buildings, of which 60% restricted structure size or building area. Working landscape easements with ranching, forestry, or farming made up nearly half (46%) of the easement properties sampled and were more likely than easements without these uses to be designated as buffers to enhance biodiversity in the surrounding area. Our results demonstrate the need for clear restrictions on building and subdivision in easements, research on the compatibility of private uses on easement land, and greater public understanding of the trade-offs implicit in the use of conservation easements for biodiversity conservation.  相似文献   
46.
定位研究了25a来缙云山银木荷林物种组成及多样性在自然演替过程中的动态变化。结果表明,银木荷林维管植物物种由57种(隶属于24科,46属)减少到38种(隶属于19科,26属)。林下草本和层间植物逐渐消失,胸径大于7.5cm的乔木层树总胸断面积有所减少。尽管群落物种组成以及多样性发生改变,但是银木荷依然是优势树种,处于林冠层,而林冠亚层的白毛新木姜子、四川山矾、长蕊杜鹃逐渐增多,短刺米槠逐渐减少。群落乔木层4个α多样性指数都呈下降趋势,丰富度指数由2.98下降为1.99,Shannon-Wiener指数25a间减小了0.34,Simpson指数和Pielou指数变化都很小;β多样性分析结果显示,银木荷群落的物种差异很大。研究表明,25a间群落物种差异显著。揭示缙云山银木荷林自然演替过程中的物种组成和多样性变化规律,可为缙云山保护区及长江流域中上游亚热带常绿阔叶林的银木荷群落的管理提供一定的参考价值。  相似文献   
47.
We documented valley and channel characteristics and wood loads in 19 reaches of forested headwater mountain streams in the Bighorn National Forest of northern Wyoming. Ten of these reaches were in the Upper Tongue River watershed, which has a history of management including timber harvest, tie floating, and road construction. Nine reaches were in the North Rock Creek watershed, which has little history of management activities. We used these data to test hypotheses that (i) valley geometry correlates with wood load, (ii) stream gradient correlates with wood load, and (iii) wood loads are significantly lower in managed watersheds than in otherwise similar unmanaged watersheds. Statistical analyses of the data support the first and third hypotheses. Stream reaches with steeper valley side slopes tend to have higher wood loads, and reaches in managed watersheds tend to have lower wood loads than reaches in unmanaged watersheds. Results do not support the second hypothesis. Shear stress correlated more strongly with wood load than did stream gradient, but statistical models with valley-scale variables had greater explanatory power than statistical models with channel-scale variables. Wood loads in stream reaches within managed watersheds in the Bighorn National Forest tend to be two to three times lower than wood loads in unmanaged watersheds.  相似文献   
48.
以遥感影像数据、专题数据、DEM数据、气象站实测数据和统计数据为数据源,采用极差法、层次分析法、综合指数法、RS&GIS等方法对长白山地区的生态安全进行了评价.结果表明:长白山地区生态安全水平呈现出明显的空间差异性,整体由中部向东西两端逐渐降低.各生态安全等级面积从大到小为临界安全等级、较安全等级、不安全等级、较不安全等级、安全等级.统计了各行政单元的平均生态安全指数和等级构成,各县市生态安全水平从高到低为长白县、抚松县、安图县、和龙市、临江市,各县市的生态安全等级构成也有所差异.长白山地区生态安全水平以临界安全等级为主,整体上生态环境质量一般,系统服务功能受到了一定程度的破坏.  相似文献   
49.
于2014年10月至2015年1月采用样线调查法对黄河三角洲自然保护区秋季迁徙期和越冬期水鸟群落结构进行调查研究,调查共包括8条样线40个观测点.结果表明:(1)秋季迁徙期共记录水鸟6目14科54种,国家Ⅰ级保护鸟类5种,国家Ⅱ级保护鸟类8种;越冬期共记录水鸟5目7科31种,国家Ⅰ级保护鸟类1种,国家Ⅱ级保护鸟类4种.(2)2个时期雁形目水鸟种类和数量均占优势,豆雁(Anser fabalis)、斑嘴鸭(Anas poecilorhycha)、赤膀鸭(Anas strepera)和绿头鸭(Anas platyrhynchos)为优势物种,丹顶鹤(Grus japonensis)、东方白鹳(Ciconia boyciana)和大大鹅(Cygnus cygnus)等珍稀水鸟也有一定的种群数量.(3)秋季迁徙期水鸟种数、数量和ShannonWiener多样性指数多于或高于越冬期.(4)5种典型生境之间水鸟种类和数量存在差异,天然水域是水鸟群落的主要分布区.(5)自然生境内的水鸟种数、数量和Shannon-Wiener多样性指数一般多于或高于人工生境.相似性分析结果表明,自然生境之间水鸟群落结构相似程度高于人工生境.  相似文献   
50.
Landscapes fulfil a multitude of ecological and social functions. Due to the fact that both traditional and everyday landscapes today face many different threats, regulatory measures have been undertaken in many countries to protect and further sustainable landscape development. They include legislation as well as economic incentives. In recent years, however, it has become clear that just to have a few laws and to spend money on subsidies is not enough. Factors other than legislation are also essential to further the sustainable development of landscapes. One of the basic factors affecting the success or failure of landscape conservation measures is public acceptance of these measures. Our project took this as its starting point. The objective was to determine which conditions and factors influence acceptance positively or negatively. To this end 22 Swiss who are directly affected by nature conservation measures, in particular by mire landscape and dry meadow conservation measures, were interviewed using qualitative interview techniques. It is shown that perception, communication, and possibilities to participate are the most decisive driving factors influencing the formation of a long-lasting acceptance. Furthermore, acceptance may be based mainly on economic criteria, on usefulness, on ecological or even aesthetic aspects. It can be shown that not all of these motivations lead to a long-lasting acceptance. Ecologically based acceptance seems the most promising because it is founded on general convictions. Economic incentives--though important--seem to generate only superficial acceptance and do not seem to be as important as is usually assumed.  相似文献   
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