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231.
Julia Ohl Alexander Wezel Glenn H. Shepard Jr. Douglas W. Yu 《Environment, Development and Sustainability》2008,10(6):827-843
In this study, we investigate whether traditional swidden agriculture on nutrient-poor tropical soils can sustainably support
a growing indigenous population within Manu National Park, Peru. Based on interviews with 50 Matsigenka farmers, as well as
GPS mapping and field visits, we established the location and size of all 124 swidden gardens cultivated in 2000 and 2001.
Using a GIS-based soil map of Manu Park, we identify the total extent of potential arable land (1) throughout the park zones
currently available for Matsigenka habitation, and (2) within the vicinity of the two study communities. Taking into account
current per capita garden size, cultivation and fallow practices, we calculate the maximum human carrying capacity of swidden
agriculture for (1) all available park zones and (2) the immediate vicinity of the two current communities. Even given the
second, highly limited scenario, the sustainable human carrying capacity is estimated to be 2,138 individuals, which is far
higher than the current population of about 420 people. Thus, arable land does not appear to be a limiting factor for the
growth of the indigenous population in Manu Park at the current time. Other possible limiting factors for population growth
are identified and discussed. We conclude that a conservation policy of population stabilization around the current settlements
is viable in that it will not result in reduced resource availability over the next few decades, and that the challenge is
to identify and mitigate the forces causing population fissioning and spread.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
232.
ERIK GÓMEZ‐BAGGETHUN SARA MINGORRÍA VICTORIA REYES‐GARCÍA LAURA CALVET CARLOS MONTES 《Conservation biology》2010,24(3):721-729
Abstract: Researchers and conservation managers largely agree on the relevance of traditional ecological knowledge for natural resource management in indigenous communities, but its prevalence and role as societies modernize are contested. We analyzed the transmission of traditional knowledge among rural local people in communities linked to protected areas in Doñana, southwestern Spain. We studied changes in knowledge related to local practices in agriculture and livestock farming among 198 informants from three generations that cover the period in which the area transited from an economy strongly dependent on local ecosystem services to a market economy with intensified production systems. Our results suggest an abrupt loss of traditional agricultural knowledge related to rapid transformations and intensification of agricultural systems, but maintenance of knowledge of traditional livestock farming, an activity allowed in the protected areas that maintains strong links with local cultural identity. Our results demonstrate the potential of protected areas in protecting remaining bodies of traditional ecological knowledge in developed country settings. Nevertheless, we note that strict protection in cultural‐landscape‐dominated areas can disrupt transmission of traditional knowledge if local resource users and related practices are excluded from ecosystem management. 相似文献
233.
Abstract: Quantifying the extent to which existing reserves meet conservation objectives and identifying gaps in coverage are vital to developing systematic protected‐area networks. Despite widespread recognition of the Philippines as a global priority for marine conservation, limited work has been undertaken to evaluate the conservation effectiveness of existing marine protected areas (MPAs). Targets for MPA coverage in the Philippines have been specified in the 1998 Fisheries Code legislation, which calls for 15% of coastal municipal waters (within 15 km of the coastline) to be protected within no‐take MPAs, and the Philippine Marine Sanctuary Strategy (2004), which aims to protect 10% of coral reef area in no‐take MPAs by 2020. We used a newly compiled database of nearly 1000 MPAs to measure progress toward these targets. We evaluated conservation effectiveness of MPAs in two ways. First, we determined the degree to which marine bioregions and conservation priority areas are represented within existing MPAs. Second, we assessed the size and spacing patterns of reserves in terms of best‐practice recommendations. We found that the current extent and distribution of MPAs does not adequately represent biodiversity. At present just 0.5% of municipal waters and 2.7–3.4% of coral reef area in the Philippines are protected in no‐take MPAs. Moreover, 85% of no‐take area is in just two sites; 90% of MPAs are <1 km2. Nevertheless, distances between existing MPAs should ensure larval connectivity between them, providing opportunities to develop regional‐scale MPA networks. Despite the considerable success of community‐based approaches to MPA implementation in the Philippines, this strategy will not be sufficient to meet conservation targets, even under a best‐case scenario for future MPA establishment. We recommend that implementation of community‐based MPAs be supplemented by designation of additional large no‐take areas specifically located to address conservation targets. 相似文献
234.
化工厂排放SO2对周围植物的影响 总被引:6,自引:0,他引:6
对某厂区及常年盛行风下风向地区植物受SO2危害情况进行了调查,并测定了部分植物叶片中的硫含量。从植物叶片中的硫含量可间接地判断大气被SO2污染的程度及植物对SO2吸收与抵抗能力的强弱。 相似文献
235.
236.
Anthony Preen 《Environmental management》1998,22(2):173-181
/ The coastal zone of the Indian Ocean is coming under increasing pressure from human activities. Australia may be one of the few countries in this region that can afford to take adequate conservation measures in the near future. As it also has one of the longest Indian Ocean coastlines, Australia has the opportunity, and responsibility, to make a meaningful contribution to the conservation of Indian Ocean biodiversity. Threatened species, including marine turtles, inshore dolphins, and dugongs are an important component of that biodiversity. The dugong has been exterminated from several areas in the Indian Ocean, and it appears to be particularly threatened by mesh netting andhunting. Its long-term survival may depend on adequate protection in Australia, which contains the largest known Indian Ocean populations. This protection will require, in part, an appropriate system of marine protected areas (MPAs). This paper examines the adequacy of MPAs along Australia's Indian Ocean coast. Dugongs occur in two MPAs in Western Australia. The proposed expansion of the system of marine reserves is based primarily on representative samples of ecosystems from each biogeographic region. It is inadequate because it does not take into account the distribution and relative abundance of threatened species. If the conservation of biodiversity is to be maximized, the system of MPAs should incorporate both representativeness and the needs of threatened species. The level of protection provided by MPAs in Western Australia is low. Under current government policy potentially damaging activities, including commercial fishing, seismic surveys, and oil and gas drilling are permitted in protected areas.KEY WORDS: Marine protected areas; Dugongs; Western Australia; Indian Ocean; Conservation; Biodiversity 相似文献
237.
塔里木沙漠油田开发工程的环境影响评价 总被引:1,自引:0,他引:1
塔里木是一个内陆封闭盆地,是世界第二大流动沙漠,它具有丰富的油气资源,目前正在积极开发中。在油气田开发过程中必须做环境影响评价,文中介绍了沙漠环境及生态状况,在沙漠区域必须以水域和生态环境影响评价为重点,评价结果应提出固沙、防沙和保护自然生态等一系列防治措施和对策。 相似文献
238.
Mekong River Fish Conservation Zones in Southern Laos: Assessing Effectiveness Using Local Ecological Knowledge 总被引:2,自引:0,他引:2
Small-scale fisheries are important in Laos, where rural people heavily depend upon Mekong River and tributary fish stocks
for their livelihoods. Increasing pressures from human exploitation and habitat disturbance, however, have raised serious
concerns about the potential depletion of various species. This has led to the establishment of large numbers of Fish Conservation
Zones (FCZs) or “no-take” fish sanctuaries in southern Laos based on a “community-based fisheries co-management” framework.
This study uses the local ecological knowledge (LEK) of fishers to assess the effectiveness of village-managed FCZs in enhancing
fish stocks in the mainstream Mekong River in Khong District, Champasak Province. Focus group interviews about species that
are believed to have benefited from different FCZs are compared with parameters such as FCZ area, age, depth, localized gradient,
water velocity, and the presence of wetland forests nearby. The results suggest that no one aspect is likely to account for
variations in fish stocks; rather, it is the interaction between numerous factors that has the largest impact. Secondly, the
results indicate that microhabitat diversity and protection are critical for maintaining and enhancing Mekong fisheries. Deep-water
pools are particularly important as dry season refuges for many fish species, and FCZ depth may be the single most important
environmental factor affecting the success of FCZs in the Mekong River. FCZs have the most potential to benefit relatively
sedentary species, but may also benefit highly migratory species, given the right conditions. This study shows that integrated
approaches to stock assessment that employ LEK and scientific fisheries management have considerable potential for improving
Mekong capture-fisheries management. 相似文献
239.
240.
彭国生 《中国安全科学学报》2003,13(5):20-23
从油田企业生产的工艺特点、历史条件、社会背景以及跨国经营合作等方面出发 ,分析了油田企业安全生产特殊性。同时指出了目前油田企业安全管理存在着四方面的主要问题 ,并针对存在的主要问题 ,提出了更新管理观念、强化安全生产责任制、加大科技投入、完善HSE体系标准、加强隐患治理、加大培训力度等 6项安全管理对策 ,对油田企业安全生产具有一定的指导意义。 相似文献