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211.
Abstract:  Central America is exceptionally rich in biodiversity, but varies widely in the attention its countries devote to conservation. Protected areas, widely considered the cornerstone of conservation, were not always created with the intent of conserving that biodiversity. We assessed how well the protected-area system of Central America includes the region's mammal diversity. This first required a refinement of existing range maps to reduce their extensive errors of commission (i.e., predicted presences in places where species do not occur). For this refinement, we used the ecological limits of each species to identify and remove unsuitable areas from the range. We then compared these maps with the locations of protected areas to measure the habitat protected for each of the region's 250 endemic mammals. The species most vulnerable to extinction—those with small ranges—were largely outside protected areas. Nevertheless, the most strictly protected areas tended toward areas with many small-ranged species. To improve the protection coverage of mammal diversity in the region, we identified a set of priority sites that would best complement the existing protected areas. Protecting these new sites would require a relatively small increase in the total area protected, but could greatly enhance mammal conservation.  相似文献   
212.
资源核算及其纳入国民经济核算体系初步研究   总被引:16,自引:0,他引:16  
实施资源核算并将其纳入国民经济核算体系是保障和促进国民经济持续、稳定、协调发展的重要措施之一。本文论述了对这一问题初步研究的基本思路、框架、方法,并以1988年我国森林资源状况为研究范例,说明了核算方法的具体应用。  相似文献   
213.
白鱀豚是我国特有的珍稀淡水哺乳动物,仅分布于长江中下游,目前长江白鱀豚的种群数量仅约200头,濒临灭绝。造成白鱀豚濒危的主要威胁来自长江鱼类资源的减少、有害渔具的广泛使用、航运事业的发展、河道的大规模整治、水电工程的建设、水体污染以及白鱀豚自身的生理特征。通过我们多年的研究,提出了建立半自然白鱀豚保护区、人工饲养下白鱀豚的繁殖,和建立长江白鱀豚自然保护区等三大措施。在各级政府和科研部门的共同努力下,三项措施正在落实,为保护白鱀豚创造了良好的条件,但面临的困难还很多,任务十分艰巨,我们希望开展广泛的国际合作,为保护白鱀豚共同努力。  相似文献   
214.
In recent years, churches across the world have become involved in dialogue on the theory and practice of sustainable development. A number of Western churches have expressed their concern about climate change and destructive living patterns, stressing the need for human beings to exercise the care for all creation based on a life of sharing and sacrifice. Some Orthodox churches, however, quite recently included the environmental issues in their agendas. While the Bases of Social Concept, a major doctrine of the Russian Orthodox Church adopted in 2000, for the first time emphasises the Churchs position in overcoming environmental crisis and presents a solid basis on which to build the future environmental strategy of the Church, the Ethiopian Orthodox Church has not yet drawn up a programme document that might serve as a framework for the Churchs current extensive activities in the field of biodiversity conservation and sustainable forestry practices. Hence, despite certain closeness of both institutions, there is the potential for strengthening their roles in promoting sustainable development, based on the Biblical concept that the Earth belongs to the Lord and humans are responsible stewards assigned the duty to work for creation and care for it. This paper seeks to demonstrate by means of comparable analysis between the two Churches, Orthodox in nature but different in rites and religious practices, that traditional, highly conservative faiths may serve as powerful instruments of spreading out the ideas of sustainable development as the basis of spiritual revival in the situation of the two concurrent and interrelated crises – spiritual and ecological.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
215.
The International Union for Conservation of Nature's Red List of Threatened Species (IUCN Red List) is the world's most comprehensive information source on the global conservation status of species. Governmental agencies and conservation organizations increasingly rely on IUCN Red List assessments to develop conservation policies and priorities. Funding agencies use the assessments as evaluation criteria, and researchers use meta-analysis of red-list data to address fundamental and applied conservation science questions. However, the circa 143,000 IUCN assessments represent a fraction of the world's biodiversity and are biased in regional and organismal coverage. These biases may affect conservation priorities, funding, and uses of these data to understand global patterns. Isolated oceanic islands are characterized by high endemicity, but the unique biodiversity of many islands is experiencing high extinction rates. The archipelago of Hawaii has one of the highest levels of endemism of any floristic region; 90% of its 1367 native vascular plant taxa are classified as endemic. We used the IUCN's assessment of the complete single-island endemic (SIE) vascular plant flora of Kauai, Hawaii, to assess the proportion and drivers of decline of threatened plants in an oceanic island setting. We compared the IUCN assessments with federal, state, and other local assessments of Kauai species or taxa of conservation concern. Finally, we conducted a preliminary assessment for all 1044 native vascular plants of Hawaii based on IUCN criterion B by estimating area of occupancy, extent of occurrence, and number of locations to determine whether the pattern found for the SIE vascular flora of Kauai is comparable to the native vascular flora of the Hawaiian Islands. We compared our results with patterns observed for assessments of other floras. According to IUCN, 256 SIE vascular plant taxa are threatened with extinction and 5% are already extinct. This is the highest extinction risk reported for any flora to date. The preliminary assessment of the native vascular flora of Hawaii showed that 72% (753 taxa) is threatened. The flora of Hawaii may be one of the world's most threatened; thus, increased and novel conservation measures in the state and on other remote oceanic islands are urgently needed.  相似文献   
216.
三峡植物物种多样性保护,重点在珍稀濒危植物,但对建群种和有实用价值的种也进行收集保存。7年来试验站保存三峡库区植物200余种,迁移成活率93%,有8种未成功。(1)到2002年已有30余种植物正常开花结实(其中木本植物24种),可以选择繁殖试验,以达到保存的目的;(2)选择了8种植物,进行生长观测,在人为控制下,生长速度满意;(3)进行了部份种类的扦插繁殖和孢子繁殖,获得了相关结果;(4)少数种类收集遇到极大困难,需要继续努力。三峡库区生物多样性研究与保护,存在一些问题与困难,如漏项问题、库区物种问题、外来种问题、隔离对生物多样性的影响问题、生物多样性的功能问题等需要进一步研讨,从而使库区物种得以保存,环境得以优化,生物资源得到持续利用。  相似文献   
217.
Implicit psychological constructs are effective predictors of behavioral outcomes but are rarely used in organizational settings because of real or imagined problems with measurement validity and administration. To address these concerns, we present a means of assessing implicit constructs quickly and easily by using psychological capital as an example. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
218.
根据隧道施工地质灾害成因与特性,对隧道施工地质灾害进行分类,并对其特点进行分析,提出隧道施工地质灾害防治原则。在建立隧道施工地质灾害监测与预警系统的基础上,对常见灾害中的塌方、涌水、突泥、瓦斯爆炸、岩爆等现象提出防治措施,旨在为隧道安全施工提供参考。  相似文献   
219.
指出制定化工园区周边控制距离过程中需要考虑的重要因素,确定了化工园区外围控制距离中的严禁建设区域和缓冲区域的范围,为城市规划中化工园区外围地域的合理规划提出了依据。同时提出减缓化工园区对园区外影响的措施。  相似文献   
220.
This study was conducted in Gwayi Valley Conservation Area in Zimbabwe. The objective was to evaluate the level of environmental awareness raising among rural communities resettled by government in a wildlife conservation area and their behavior and actions towards biodiversity conservation. We selected three communities based on the degree of exposure to environmental awareness campaigns by various government departments and non-governmental organizations. This formed a gradient of exposure to environmental awareness campaigns, ranging from the most accessible and exposed community (Hangano), moderately exposed (Gwayi) through to the least accessible and exposed community (Karna). We used focus group discussions, key informant interviews and structured interviews with 95 respondents in the selected communities from November 2016 to April 2017. Through public awareness raising, a number of conservation groups were established including fire and hunting committees, anti-poaching teams and environmental resource monitors. While these groups were found to be either inactive or less effective in Gwayi and Karna, all were found to be very active and effective in Hangano. Similarly, community behavior and actions that caused biodiversity loss such as indiscriminate cutting of live trees, poaching, streambank cultivation, fishing in rivers with nets and use of sledges were much reduced in Hangano than in Gwayi and Karna. Frequent environmental awareness campaigns played a critical role in promoting biodiversity in Hangano. We conclude that substantial gains can be made in environmental conservation by investing more in public awareness campaigns, particularly in developing countries such as Zimbabwe where financial resources for conservation are scarce.  相似文献   
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