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331.
Abstract Due to historic reasons, there are several human settlements in nature reserves and national parks, which may constitute a threat to biodiversity. Establishment of nature reserves may however generate constraints for development of local communities residing in these reserves. The village ecosystem of Zhuanjinglou Village in Wolong Nature Reserve includes population, farming and livestock (domestic and alpine) and forest ecosystem. An emergy analysis of agro-ecosystem (including the farming and livestock ecosystem) and energy consumption in Zhuanjinglou Village indicates that livestock ecosystem plays an important role in village ecosystem, which may be the source of great pressure on the state of the local environment. The increasing ratio of electricity in energy consumption may play a positive role for environmental conservation. Despite some successful experiences, there are some remaining issues that need to be addressed in the ecological rehabilitation of the village ecosystem. 相似文献
332.
钱云 《中国环境管理干部学院学报》2013,(5):16-19
以协商的方式确定水污染物间接排放标准的规定打破了人们对标准确定性、强制性的传统认识。协定标准的优势在于充分利用污水处理厂的污水处理能力,减轻企业的污水处理负担,使企业可以集中力量搞生产。协定标准具有灵活性和优越性,应充分利用。通过对协定标准概念和重要性的分析,指出协定标准存在效力不确定、缺少对协定范围的限制等问题,造成协定标准在实践中通常被忽视或者滥用。并从明确协定标准的范围、加强排污企业的管理和协定标准的监督等方面,进一步提出了限制和完善水污染物间接排放标准的建议。 相似文献
333.
Tendencies in plant cover synanthropization depending on the pattern and intensity of anthropogenic impacts on natural complexes have been revealed in specially protected areas of different classes (a nature reserve and a nature park). 相似文献
334.
SVEN E. KERWATH†† EVA B. THORSTAD† TOR F. NÆSJE†§ PAUL D. COWLEY§ FINN ØKLAND† CHRIS WILKE COLIN G. ATTWOOD‡ 《Conservation biology》2009,23(3):653-661
Abstract: The application of no-take areas in fisheries remains controversial. Critics argue that many targeted species are too mobile to benefit from area protection and that no-take areas are only appropriate for resident species. The degree of protection does not depend on the size of the no-take area but rather on the time fish reside inside its boundaries during key life-history events (i.e., spawning) and during periods of peak fishing activity. We evaluated the potential of a small no-take marine protected area (MPA) inside a coastal embayment as a harvest refuge for a mobile, possibly migratory, long-lived fish species. We used acoustic telemetry to track movements of 30 transmitter-tagged white stumpnose (Rhabdosargus globiceps) across and on both sides of the boundary of a small (34 km2 ) no-take area over a full year. Being landlocked on 3 sides, the location of the MPA inside the lagoon made it practical to detect all boundary crossings and to calculate the time individual fish used the MPA. We detected frequent movements across the boundary, with strong seasonal and individual variations. There were significant differences in MPA use patterns between fish from different release areas. The time spent in the MPA by individual fish during summer (mean 50%; max 98%) was out of proportion with the size of that area (4% of total habitat). Summer coincided with peak recreational fishing activity and with the spawning season of this species. The small MPA provided a refuge for a part of the spawning stock of white stumpnose. Our findings suggest that if strategically placed, a small no-take area can be effective in protecting mobile species and that models of spillover from no-take areas should account for seasonal and individual variation in area use and the spatiotemporal distribution of fish and fishers. 相似文献
335.
EDWARD T. GAME EVE McDONALD‐MADDEN MARJI L. PUOTINEN HUGH P. POSSINGHAM 《Conservation biology》2008,22(6):1619-1629
Abstract: It is thought that recovery of marine habitats from uncontrollable disturbance may be faster in marine reserves than in unprotected habitats. But which marine habitats should be protected, those areas at greatest risk or those at least risk? We first defined this problem mathematically for 2 alternate conservation objectives. We then analytically solved this problem for both objectives and determined under which conditions each of the different protection strategies was optimal. If the conservation objective was to maximize the chance of having at least 1 healthy site, then the best strategy was protection of the site at lowest risk. On the other hand, if the goal was to maximize the expected number of healthy sites, the optimal strategy was more complex. If protected sites were likely to spend a significant amount of time in a degraded state, then it was best to protect low‐risk sites. Alternatively, if most areas were generally healthy then, counterintuitively, it was best to protect sites at higher risk. We applied these strategies to a situation of cyclone disturbance of coral reefs on Australia's Great Barrier Reef. With regard to the risk of cyclone disturbance, the optimal reef to protect differed dramatically, depending on the expected speed of reef recovery of both protected and unprotected reefs. An adequate consideration of risk is fundamental to all conservation actions and can indicate surprising routes to conservation success. 相似文献
336.
JAMES R. HERKERT 《Conservation biology》2009,23(4):1036-1040
Abstract: The role of agricultural landscapes in biodiversity conservation has been largely ignored despite their potential role in conserving declining species. Within agricultural landscapes, set-aside programs may offer the most promising conservation opportunities due to the large area involved in these programs. I explored the relationship between set-aside effect size—on the basis of data from field studies of birds in cropland and set-aside fields—and population changes following establishment of these fields. Species whose abundance was most strongly influenced by the establishment of set-aside lands also tended to show positive changes in population trends following broad-scale implementation of the set-aside program. This relationship was strongest for grassland obligate birds, a group of birds experiencing broad-scale population declines throughout North America. There is now increasing evidence that set-aside lands within the United States are providing population-level benefits to grassland birds. Nevertheless, there are also increasing concerns about the stability of these set-aside lands in the face of increased demand for crops and rising commodity prices. If set-aside area within the United States is allowed to decline, additional declines of birds and perhaps other taxa within agricultural landscapes seem likely. 相似文献
338.
339.
关于架构可持续发展的观念体系的深层思考 总被引:3,自引:0,他引:3
王喜法 《中国人口.资源与环境》2002,12(2):10-15
本文着重从把握人与自然共生的辩证关系方面入手分析 ,认为体系的框架主要有五个层面 :即在人与自然的关系上 ,确立人与自然的和谐观 ;在发展经济与保护生态的关系上 ,确立经济与生态的兼容观 ;在处理各方利益关系上 ,确立经济、生态和社会三个效益的统一观 ;在生产增长的理念上确立集约化经营观 ;在生活方式选择上 ,确立适度消费观。在实践中 ,我们要把这种新的观念变成推动经济社会可持续发展的自觉力量 ,这就需要通过宣传教育、政策导向、责任考核、现代科技的“生态化”发展以及法制建设等途径 相似文献
340.