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311.
Protected areas (PAs) represent a key global strategy in biodiversity conservation. In tropical developing countries, the management of PAs is a great challenge as many contain resources on which local communities rely. Collection and trading of non-timber forest products (NTFPs) is a well-established forest-based livelihood strategy, which has been promoted as a potential means for enhanced conservation and improved rural livelihoods in recent years, even though the sustainability or ecological implications have rarely been tested. We conducted an exploratory survey to understand the role and stakeholder views on conservation prospects and perceived ecological feasibility of NTFPs and harvesting schemes in a northeastern PA of Bangladesh, namely the Satchari National Park. Households (n?=?101) were interviewed from three different forest dependency categories, adopting a stratified random sampling approach and using a semi-structured questionnaire. The study identified 13 locally important NTFPs, with five being critically important to supporting local livelihoods. Our study suggests that collection, processing and trading in NTFPs constitutes the primary occupation for about 18% of local inhabitants and account for an estimated 19% of their cash annual income. The household consensus on issues relating to NTFPs and their prospective role in conservation was surprisingly high, with 48% of respondents believing that promotion of NTFPs in the PA could have positive conservation value. The majority (71%) of households also had some understanding of the ecological implications of NTFP harvesting, sustainability (53%) and possible management and monitoring regimes (100%). With little known about their real application in the field, our study suggests further investigations are required to understand the ecological compatibility of traditional NTFP harvesting patterns and management.  相似文献   
312.
Developing indicators to more effectively evaluate poverty–environment dynamics and inform policy is an urgent research priority. It is critical that these indicators are used in ways that accurately represent the relationship they are meant to inform. This article evaluates the theory and use of poverty–environment indicators, a relatively new tool developed to aid in the design and evaluation of poverty reduction strategies in the context of environmental change. We argue that while they have great potential, in their current form and use, poverty–environment indicators may contribute to critical misunderstandings of processes on the ground. These issues stem from a problematic and largely unacknowledged process of simplifying particular poverty–environment relationships. This article lays out the problematic character of this simplification process, and suggests how we might address these problems to create more useful understandings of poverty–environment dynamics to inform policy.  相似文献   
313.
The increasing interest in environmental conservation is a global phenomenon. In many countries, natural reserves or protected areas (PAs) have been established to restrict human activities and to enhance natural ecosystems, which potentially benefit the planet as a whole. However, this often demands some sacrifices from local residents who may have to give up resources they rely on or suffer losses caused by wildlife. This issue potentially becomes aggravated in densely populated areas where many people and economic activities are impacted. This paper presents research findings on poverty issues in a newly established national natural reserve in China, Hengshui Lake Natural Reserve. The paper addresses the characteristics of poor households in the reserve and the interaction between these families and the reserve. In addition, poverty alleviation measures are analysed and additional measures to reduce poverty and conflicts between the reserve and local residents are recommended.  相似文献   
314.
It is well known that whilst wetlands deliver a wide range of services vital for human well-being, they are being rapidly degraded and lost. Losses tend to be higher where human populations are increasing most and demands for economic development are greatest. Multidisciplinary management approaches that integrate conservation and development objectives in wetlands are therefore urgently requested for by the Ramsar Convention on Wetlands. This paper describes the evaluation of 10 wetland management case studies from Asia, Africa and South America that adopted such an integrated approach. The evaluation assessed the outcomes of these integrated initiatives to identify conditions and processes for linking conservation and poverty reduction objectives in wetlands. The findings are also compared with other assessments of integrated approaches, particularly in terms of their effectiveness in optimizing conservation and poverty reduction outcomes. The results from our studies suggest an ongoing evolution of such integrated interventions, which also implies cycles of learning from past mistakes. Overall, our results highlight the significant variation between wetlands in types and quantities of services they provide and emphasize the need to view many ecological issues as social challenges for equitable solutions to both wetlands and people. The analysis further shows that the positive on-ground results owe much to the interdisciplinary problem analysis, whereby interventions can move from treating symptoms to addressing root causes. while no blueprint emerged on how to successfully integrate conservation and poverty reduction in wetlands, important lessons for future interventions were drawn.  相似文献   
315.
辽宁沿海地区用水效率与经济的耦合协调发展评价   总被引:4,自引:1,他引:3  
论文构建辽宁沿海经济带用水效率与经济耦合协调发展评价指标体系,首先运用改进的突变模型对2001—2010 年辽宁沿海经济带用水效率和经济发展各子系统进行状态评估,其次运用耦合协调模型对辽宁沿海经济带各市用水效率与经济发展的耦合协调度进行评价。研究结果表明:①辽宁沿海经济带整体用水效率与经济发展耦合度水平从0.437 提高到0.498,呈缓慢提高状态,但一直处于拮抗阶段。用水效率水平与经济发展水平差距不断减小,耦合协调度从0.254 增大到0.408,呈增大趋势但仍处于中低度协调水平;②辽宁沿海经济带各市用水效率与经济发展都处于上升趋势,其中用水效率最好的为大连市,用水效率评估值已达到0.887,其次为锦州、营口和葫芦岛,丹东和盘锦市用水效率处于最低水平,分别为0.604和0.535。经济发展水平最高的为大连市,其次为营口和盘锦市,丹东、锦州和葫芦岛较差; ③各市耦合度均处于拮抗阶段,并且处于上升趋势。大连市和营口市耦合协调度2010年已分别达到0.457 和0.401,已从低度协调进入中度协调且呈不断上升趋势,丹东、锦州、盘锦和葫芦岛均处于低度协调阶段,呈波动式上升。各市的经济发展滞后于水资源利用效率的提高,导致耦合协调度一直处于中低度协调水平;④辽宁沿海经济带耦合度和协调度的区域差距在不断减小,经济带协同发展趋势越加明显。  相似文献   
316.
辽河干流消落区沉积物重金属污染特征研究   总被引:4,自引:0,他引:4       下载免费PDF全文
刘强  梁雷  王峰源  刘峰 《中国环境科学》2013,33(12):2220-2227
通过测定辽河干流消落区10个断面中0~5cm、5~15cm、15~30cm深沉积物中重金属Pb、Cu、Zn、Cd含量,揭示消落区干-湿交替下沉积物重金属的污染特征.采用原子吸收分光光度计测定重金属含量,并采用地质累积指数与潜在生态危害指数评估重金属污染状况.结果表明,除Cd外,Cu、Zn与Pb的含量均值分别为31.4mg/kg、28.14mg/kg、43.75mg/kg,均低于中国土壤环境质量标准I级土壤标准;Cd含量均值1.438mg/kg,是中国土壤环境质量标准I级土壤标准的7.19倍,是辽河水系沉积物平均值的1.29倍,辽宁省土壤背景值的13.31倍,表明研究区Cd污染严重.地质累积指数评价表明,Pb、Cu、Zn的污染程度低于1级,Cd达2级中度污染以上,在通江口达3.92,为5级强污染;据潜在生态危害评价,达牛渡口上游干流潜在生态危害指数为强以上,通江口生态危害指数最高,且生态危害主要来源于Cd.相关性分析表明,Pb、Cu与Zn间相关性极显著,可能有相同的污染源,Cd有单独的污染源.  相似文献   
317.
长期以来,学者对中国农村贫困的研究侧重于经济贫困方面,对能源贫困的研究相对不足,而能源贫困恰恰是制约农村地区发展和农户生计资产改善的主要因素。论文从农户的视角出发,借鉴巴西、印度等发展中国家的能源贫困线标准,根据农户调查和访谈,对中国农村能源贫困线进行了综合考量,并最终确定为户均每年消费400 kgce;为科学测度能源贫困状况,提出从能源贫困的广度、深度、差异度三个维度进行定量分析,并构建了各维度的测度方法;以云南省怒江州为案例,利用564 份农户调查问卷,分析了怒江州的能源贫困状况,研究发现,怒江州能源贫困的广度为0.66,能源贫困的深度为0.40,能源贫困的差异度为0.17,能源贫困的综合指数(Sen指数)为0.37,说明怒江州的能源贫困状况是比较严重的,并据此提出了具有针对性的政策建议。  相似文献   
318.
为研究城市道路两侧不同绿化带宽度及不同植物群落配置模式对消减大气中PM2.5浓度的作用,选择北京市四环主干道旁3种典型植物群落配置类型作为试验监测点,对0 m、6 m、16 m、26 m、36 m不同绿带宽度下PM2.5浓度分布与变化进行监测,并对其消减能力进行计算,分析PM2.5浓度变化与道路车流量、绿化带宽度及植物群落配置模式之间的关系。结果表明:(1)PM2.5浓度的日变化与车流量的日变化特征一致,道路绿地空气中PM2.5浓度的日变化呈现双峰单谷型特征,即早晚高、白天低,PM2.5浓度在8:00-10:00的交通早高峰期间增加,而后开始下降,到12:00-14:00左右达到最低值,之后呈持续上升状态,直至晚高峰19:00浓度达一天中的最大值。(2)不同植物群落配置模式对大气中PM2.5浓度的消减作用不同,群落内郁闭度高的多复层结构绿地对PM2.5消减作用优于郁闭度低的单层配置绿地模式;(3)分别对3类空气质量条件下,道路绿地对PM2.5消减作用进行评价。无污染或轻度污染(PM2.5〈100μg·m-3)环境下,绿地对PM2.5消减作用明显,26 m及36 m的绿带处消减作用最强,最高可达12.22%;中度污染(101μg·m-3201μg·m-3)天气条件下3种绿地对PM2.5的消减作用均不明显。  相似文献   
319.
阐述了生物防火林带在森林防火、经济建设和生态保护方面的作用和效益,分析了在防火树种选择、防火林带营造方面应遵循的原则和应注意的问题。  相似文献   
320.
对平果热电厂皮带上煤除尘系统失效进行了故障诊断 ,对故障产生的主要原因诱导风流进行了详细的分析 ,采取了可行的改进措施  相似文献   
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