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101.
Ecological approaches to drawing boundaries for parks and reserves are developed, described as 15 guidelines. The five abiotic guidelines are designed with the principle objective of maintaining drainage basin integrity. The ten biotic guidelines are designed to reduce as little as possible the natural diversity of populations in both the total natural area and in the communities directly traversed by the boundary line. Three of the biotic guidelines apply to maintaining community diversity, the remainder to species diversity. These guidelines are applied to a 2500-km2 potential national park in a montane environment in the southwest Yukon Territory. They were successful in generating the conclusion that boundaries in the subalpine best satisfy the guidelines in this environment.  相似文献   
102.
李群绩  梅林  王灵恩 《资源开发与保护》2012,(11):1036-1039,F0004
吉林大布苏国家级自然保护区的主要生态风险源来自人类活动,该保护区目前以开展生态旅游为主。以吉林省大布苏国家级自然保护区为例,运用生态风险评估的一般方法系统分析影响其生态风险的因素,确定其主要生态风险源为干旱、盐碱化、水土流失和人类活动,其中人类活动造成的影响特别突出。将ArcGIS应用于生态风险的评价当中,结合2004--2011年土地利用类型变化,绘制综合生态风险等级分布图,提出针对性的旅游开发对策以降低该保护区面临的生态风险,实现吉林省大布苏国家级自然保护区的可持续发展。  相似文献   
103.
结合2011年阿尔金山保护区水文地质科学考察工作,在对保护区地表水水系、水体类型及特征进行调查分析的基础上,采集了主要地表水体类型的水化学样本,对各样本中的阴阳离子含量、矿化度、pH等水化学指标进行了测试,分析了保护区主要地表水类型的水化学现状特征及其空间变化规律,并与历史调查资料进行了对比分析,探讨了近30年保护区地表水水化学特征发生的变化及主要原因。  相似文献   
104.
岭南自然保护区药用蕨类植物资源十分丰富,共有32科48属79种,论述了药用蕨类植物的生境、药用部位、采收状况,并结合当地的实际情况,提出了保护和开发利用建议.  相似文献   
105.
The theoretical concept, “asset specificity,” is applied to real data in the context of Danish nature conservation network planning in order to produce illustrative examples of an economic measure of the network’s vulnerability to exogenous shocks to the species composition. Three different measures of asset specificity are quantified from the shadow value of eliminating a key species from the individual grid cells. This represents a novel approach and a different interpretation of the term, as it is conventionally used as a qualitative indicator in the transaction cost economics literature. Apart from supplementing existing cost measures with an indicator of risk associated with investments in protected areas, this study demonstrates how the estimation and interpretation of various asset specificity measures for geographical areas may qualify policy makers’ choice of policy instrument in conservation planning. This differs from the more intuitive approach of basing policy instrument choice solely on the rarity of the species in a given area.  相似文献   
106.
在分析陕西秦岭大熊猫自然保护区发展现状的基础上,对其建设管理与周边社区经济社会中存在的问题进行了分析,探讨了自然保护区与周边社区的相互影响关系,提出了大熊猫自然保护区与社区协调发展的对策建议.  相似文献   
107.
本文初步分析了卧龙自然保护区野生植物资源的特点和存在的问题,提出了野生植物资源利用和保护的生态经济对策。  相似文献   
108.
To date seagrass monitoring has involved the removal of seagrass from its environment. In fragile or highly disturbed systems, monitoring using destructive techniques may interfere with the environment or add to the burden of disturbance. Video photography is a form of non-destructive monitoring that does not require the removal of seagrass or interference with the environment and has the potential to be a valuable tool in monitoring seagrass systems. This study investigated the efficacy of video photography as a tool for detecting change in seagrass cover, using the temperate Australian species Amphibolis antarctica (Labill.) Sonder ex Aschers. Using visual and random point estimates of seagrass cover from video footage, it was possible to determine the minimum sample size (number of random video frames) needed to detect change in seagrass cover, the minimum detectable change in cover and the probability of the monitoring design committing a Type II error. Video footage was examined at three scales: transects (m apart), sites (km apart) and regions (tens of km apart). Using visual and random point estimation techniques, a minimum sample size of ten quadrats per transect was required to detect change in uniform and variable seagrass cover. With ten quadrats it was possible to identify a minimum detectable change in cover of 15% for uniform and 30% for variable seagrass cover. Power analysis was used to determine the probability of committing a Type II error from the data. Region level data had low power, corresponding to a high risk of committing a Type II error. Site and transect level data had high power corresponding to a low risk of committing a Type II error. Based on this study's data, managers using video to monitor for change in seagrass cover are advised to use data from the smaller scale, for example, site and transect level data. By using data from the smaller scale, managers will have a low risk of incorrectly concluding there has not been a disturbance when one has actually occurred.  相似文献   
109.
Ecological Compensation in Dutch Highway Planning   总被引:13,自引:0,他引:13  
The ecological compensation principle was introduced by the Dutch government in 1993. This principle is designed to enhance the input of nature conservation interests in decision-making on large-scale development projects and to counterbalance the ecological impacts of such developments when implemented. This article evaluates the application of the Dutch compensation principle in highway planning. Six current highway projects reveal consistent implementation of this principle, although provincial policies on compensation and a national method for identifying compensation measures are still under development. As the planning process has not yet been completed for all the projects, no general conclusions can be drawn on the impact of the compensation principle on highway decision-making. Nevertheless, several examples show that the principle stimulates project initiators to develop alternative routes or route sections in order to avoid or reduce ecological impacts and the need for coherent compensation measures. If the compensation principle is to be properly implemented in the context of highway planning, particular attention should be paid to the following aspects: (1) sequential assessment of overall project legitimacy and the necessity of intersecting protected areas and compensation measures, (2) the initiator's attempts to avoid and mitigate ecological impacts in developing alternative routes prior to compensation for impacts, and (3) the role of uncertain ecological impacts in identifying compensation measures, especially those concerning habitat isolation.  相似文献   
110.
通过论述八岔岛国家级自然保护区野生动物种类及组成,对保护区内鱼类、鸟类、兽类、两栖类、爬行类等物种种类进行了介绍。八岔岛国家级自然保护区在对动植物进行保护的同时,面临着大规模土地开发,非法狩猎及灭绝性捕捞,农药、除草剂、化肥的大量使用等环境问题。针对保护区的环境保护现状,通过开展宣传教育、协调发展与保护的关系、加强管理和执法并完善相关法律、建立珍稀濒危野生动物保护地、加强相关领域研究、开展广泛合作并加强资金投入等措施,可以更有效地改善八岔岛保护区野生动物生存环境。  相似文献   
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