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991.
There is profound interest in knowing the degree to which China's institutions are capable of protecting its natural forests and biodiversity in the face of economic and political change. China's 2 most important forest‐protection policies are its National Forest Protection Program (NFPP) and its national‐level nature reserves (NNRs). The NFPP was implemented in 2000 in response to deforestation‐caused flooding. We undertook the first national, quantitative assessment of the NFPP and NNRs to examine whether the NFPP achieved its deforestation‐reduction target and whether the NNRs deter deforestation altogether. We used MODIS data to estimate forest cover and loss across mainland China (2000–2010). We also assembled the first‐ever polygon dataset for China's forested NNRs (n = 237, 74,030 km2 in 2000) and used both conventional and covariate‐matching approaches to compare deforestation rates inside and outside NNRs (2000–2010). In 2000, 1.765 million km2 or 18.7% of mainland China was forested (12.3% with canopy cover of ≥70%)) or woodland (6.4% with canopy cover <70% and tree plus shrub cover ≥40%). By 2010, 480,203 km2 of forest and woodland had been lost, an annual deforestation rate of 2.7%. Forest‐only loss was 127,473 km2 (1.05% annually). In the NFPP provinces, the forest‐only loss rate was 0.62%, which was 3.3 times lower than in the non‐NFPP provinces. Moreover, the Landsat data suggest that these loss rates are overestimates due to large MODIS pixel size. Thus, China appears to have achieved, and even exceeded, its target of reducing deforestation to 1.1% annually in the NFPP provinces. About two‐thirds of China's NNRs were effective in protecting forest cover (prevented loss 4073 km2 unmatched approach; 3148 km2 matched approach), and within‐NNR deforestation rates were higher in provinces with higher overall deforestation. Our results indicate that China's existing institutions can protect domestic forest cover.  相似文献   
992.
This paper describes a study of the trace element distribution in sediments, marine water and mussel Mytilus galloprovincialis of the Venetian Lagoon around the Island of Murano, an island with a long tradition of glassmaking. Trace elements analysed include Fe, Mn, Zn, Cu, Cr, Pb, Ni, Ag and As. Sediments are contaminated with Zn, Cu, Ag, As and Pb, with levels in the <2m fraction that are likely to cause adverse biological effects to marine organisms. The pelite (<63m) is the main carrier of heavy metals at most sites. However, the fine-grained and coarse sand on the southern coast of Murano accounts for a significant proportion of Fe, Mn, Zn, Cr, Ag, Ni and Pb. Most trace element concentrations found in soft tissue of mussels appear to be within recommended Italian and international guidelines for shellfish for human consumption, the only exception being relatively high As levels. The bioaccumulation of Ag and Cr is more pronounced in the shell of these organisms. In the marine water of the lagoon, trace elements are more enriched than in other areas of the Mediterranean, with particular reference to the dissolved labile species of Zn, Mn, As, Cu, Ni and Cr.  相似文献   
993.
An emergy evaluation was carried out to assess the carrying capacity of a small, uninhabited island (Woosedo) off the southwestern coast of Korea. The sea area within 1 km from the high tide level of the island was included in the evaluation. The total environmental emergy input to Woosedo was 1.66E19 sej/yr, with the most emergy contribution from the tidal energy. The land and marine ecosystems of Woosedo contributed 4.97 million Em$ (7600 Em$/ha/yr) to the Korean economy annually. If Woosedo was developed to the national average at the emergy investment ratio of 2.86, its carrying capacity was estimated at 1034 people at the current living standard of Korea. With this population, the island system would not be sustainable with a very low emergy sustainability index of 0.36. At the same living standard used in the developed scenario, the carrying capacity of the island would be 370 people for a sustainable development scenario and 270 people if the renewable emergy were the only source to support the population. The emergy contribution of the marine ecosystem of the island was the major source of support in determining the level of carrying capacity of the island.  相似文献   
994.
鉴于海洋沉积物是137Cs在海域内迁移的最终归宿.建立了沉积物中污染物纵向迁移分布的定量模型,在机理分析中充分考虑了海水表层沉积物界面上通过沉降、扩散、吸附解吸等作用完成的物质传输,并对大亚湾内4个监测点底质芯样中137Cs活度进行了模拟分析,对未来底质中137Cs的富集趋势进行了预测.  相似文献   
995.
Abstract:  The physical, economic, and sociocultural displacement of local peoples from protected areas generates intense discussion among scholars and policy makers. To foster greater precision and clarity in these discussions, we used a conceptual framework from the political economy literature to examine different forms of human displacement from protected areas. Using marine protected areas (MPAs) to ground our analysis, we characterized the 5 types of property rights that are reallocated (lost, secured, and gained) through the establishment of protected areas. All forms of MPA "displacement" involve reallocation of property rights, but the specific types and bundles of rights lost, secured, and gained dramatically shape the magnitude, extent, and equity of MPA impacts—positive and negative—on governance, economic well-being, health, education, social capital, and culture. The impacts of reallocating rights to MPA resources vary within and among social groups, inducing changes in society, in patterns of resource use, and in the environment. To create more environmentally sustainable and socially just conservation practice, a critical next step in conservation social science research is to document and explain variation in the social impacts of protected areas.  相似文献   
996.
    
A recent discussion debates the extent of human in‐migration around protected areas (PAs) in the tropics. One proposed argument is that rural migrants move to bordering areas to access conservation outreach benefits. A counter proposal maintains that PAs have largely negative effects on local populations and that outreach initiatives even if successful present insufficient benefits to drive in‐migration. Using data from Tanzania, we examined merits of statistical tests and spatial methods used previously to evaluate migration near PAs and applied hierarchical modeling with appropriate controls for demographic and geographic factors to advance the debate. Areas bordering national parks in Tanzania did not have elevated rates of in‐migration. Low baseline population density and high vegetation productivity with low interannual variation rather than conservation outreach explained observed migration patterns. More generally we argue that to produce results of conservation policy significance, analyses must be conducted at appropriate scales, and we caution against use of demographic data without appropriate controls when drawing conclusions about migration dynamics. La Migración Humana, Áreas Protegidas y el Alcance de la Conservación en Tanzania  相似文献   
997.

为更好地分析规划环评的有效性,以26个产业园区规划环评为例,基于4个维度构建指标体系,分析产业园区规划环评执行取得的实质性成效和不足。结果显示,产业园区规划环评在落实总量控制和绩效要求、落实产业准入限制、保护和避让环境敏感区域等方面实质性成效显著,但在推动配套污水处理设施完备、协调人居环境安全风险、清洁生产和循环经济水平提升等方面仍有提升空间。不同园区级别上,国家级产业园区规划环评执行成效优于省级及以下园区;不同规划环评审查时期上,随着国家进一步加强产业园区规划环评工作指导和推动改革取得成效,“十三五”以来通过生态环境主管部门审查的产业园区规划环评取得实质性成效优于“十三五”之前。不同地区上,东部地区更加重视规划环评源头预防对高质量发展的引领作用,落实规划环评意见执行力较中西部地区强。基于问题导向,提出加强产业园区环境管理、加强规划环评跟踪监管以及推动多部门共同参与规划环评编制和落实等方面建议。

  相似文献   
998.
借鉴产品生命周期评价 、行业生命周期评价的基本方法,将"生命周期评价"作为方法论,运用于多行业聚集的高科技园区环境管理.以北京中关村电子城科技园发展模式为例,从景观、建筑、交通、通讯、能源和资源等6个方面,分别从原材料、设计、生产建设、运营使用和回收再利用等生命周期的5个阶段进行了分析,探讨高科技园区企业组织环境管理及资源设施环境管理问题,以解决都市日趋严峻的生态环境保护和资源节约问题,提出建设绿色、创新的高科技园区的举措.  相似文献   
999.
分区管控是实现国家公园严格保护与合理利用双重目的的基础制度,也是保障原住居民发展权益的有效途径。梳理总结各试点公园的分区管控制度,本文发现存在实体规范各行其是、程序规范先天不足、责任规范流于形式的问题,难以实现保护优先、兼顾利用之间的关系。国家公园法应统一分区标准,采取二阶结构的分区管控制度,首先以世界自然保护联盟提出的\"三圈层\"模式划分严格保护区、缓冲区、一般控制区,进而将一般控制区划分为游憩展示区和传统利用区,并将生态保育修复区作为特别的\"动态分区\"。同时,提高国家公园规划及变更的审批权限并完善分区管控的法律责任,以实现实质的差别化管控和严格规范的管理。  相似文献   
1000.
The feasibility of using U.K. coal-fired power station waste materials for artificial reef production is being examined. in June, 1989, an experimental artificial reef was constructed in Poole Bay, off the central south coast of the U.K., using three different mixtures of pulverised fuel ash (PFA), flue gas desulphurisation (FGD) gypsum and slurry, stabilized with cement and formed into blocks. Fifty tonnes of 40 × 20 × 20 cm blocks were formed into eight conical reef units replicating three different PFA/gypsum mixtures and one concrete control. the reef structure is 10m below chart datum on a flat sandy sea-bed.

Combustion of coal concentrates the heavy metal content in the resultant ash. the purpose of stabilization of the ash as blocks is twofold: to immobilize heavy metals (or other components) and to provide hard substratum for the attachment of organisms. to examine the effectiveness of this stabilization and hence the environmental compatibility of the block materials, heavy metal (Cd, Cr, Cu, Pb, Mn, Ni, Zn) content of the blocks has been monitored routinely over two years, to determine leaching rates. Sectional profiles indicate partial replacement of calcium content by magnesium. Associated with this there has also been some redistribution of heavy metals. Only in the case of cadmium has there been a detectable loss from the surface of blocks. Chromium and manganese concentrations appear to have increased. the metal content of the reef epibiota (including ascidians, Ascidia mentula; hydroids, Halecium spp.; bryozoans, Bugula spp. and red algae) growing on the ash blocks has been compared to that of epibiota attached to the concrete controls and surrounding sea-bed. to date no evidence of excess bioaccumulation of metals has been detected.

The physical integrity of the ash reef blocks has been maintained. There is evidence that the blocks are increasing in compressive strength.

An indication of the fishery enhancement potential of the experimental structure is given by the presence of eight commercially fished species (crustaceans and molluscs) including lobsters (Homarus gammarus).  相似文献   
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