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41.
济南市水资源承载力及可持续利用对策   总被引:2,自引:0,他引:2  
水是人类生存和发展的物质基础,但随着社会经济的发展,水的供需矛盾日益尖锐,水资源承载力成为水资源安全战略研究的一个基础;通过对济南水资源承载力分析和预测,为可持续发展提供对策.  相似文献   
42.
根据生态足迹的概念和计算方法,对黑龙江省2005年生态足迹进行了计算和分析。结果表明,黑龙江省2005年人均生态足迹为2.525 hm2,而实际生态承载力为1.395 hm2,人均生态足迹赤字为1.297 hm2,表明黑龙江的发展处在一种不可持续的状态。  相似文献   
43.
Farmers in the Vietnamese Mekong Delta face a wide range of climate-related and hydrological factors which threaten rice production. Smallholder farmers must adapt to climate change to sustain rice production as their central and most important livelihood activity. A sample was stratified across agro-ecological areas in the Delta affected by flooding, alluvial soils, acid sulphate soils, and saline water intrusion and by derived farmer typologies. A rural livelihoods approach was used in focus group discussions and in-depth interviews to identify and enumerate enabling and constraining adaptation factors. Smallholders experienced diverse natural hazards such as floods, abnormal rains, high temperatures, water scarcity, and salinity intrusion specific to the agro-ecological areas. Adaptation was constrained by labour shortages, water quality, topography, access to combine harvesters, transportation infrastructure, dryers and household savings. Adaptation was enabled by farming techniques and experience, cooperative groups, water quantity, access to information, and ability to purchase agro-chemicals through credit. Small farmers (< 1?ha) were more constrained than large farmers (> 1?ha) who had an expanded livelihood asset base. A range of policy implications are discussed, but adaptation is not just about technological fixes but requires overall improvements in a range of human, social and financial components.  相似文献   
44.
Can radical political‐economic transformation be achieved by electoral regimes that have not thoroughly reconstructed the state? Contemporary Venezuela offers an optimal venue for examining this question. The Chavista movement did not replace the previous state: instead, its leaders attempted to reform existing state entities and establish new ones in pursuit of its transformation agenda. It has also used its oil wealth to support cooperatively‐oriented economic activity, without necessarily fundamentally altering the property structure. Thus, the social change‐oriented political economy exists alongside the traditional one. Focusing on agrarian transformation, we examine ethnographically how these factors have impacted the state's capacity to attain its goal of national food sovereignty. We find that the state's ability to accomplish this objective has been compromised by lack of agency‐level capacity, inter‐agency conflict and the persistence of the previously‐extant agrarian property structure. These dynamics have influenced the state to shift from its initial objective of food sovereignty to a policy of nationalist food security.  相似文献   
45.
To achieve sustainability in heritage tourism, tourists should be placed at the heart of the management and planning processes. Indicators and standards-based frameworks were developed in the field of outdoor recreation management to manage and measure crowding and other problematic issues in parks and related areas. Using normative theory and visual research methods, this article aims to examine crowding standards of tourists at Petra Archaeological Park, and compare these standards between the types of heritage tourists suggested by a model developed by Bob McKercher. Results showed that tourists’ acceptability levels go down with an increasing number of tourists, and tourists who are highly motivated to visit heritage sites (i.e. purposeful and sightseeing heritage tourists) had the most restrictive acceptable number of tourists at the park. The normative standards formulated in this article provided a guidance to manage crowding at Petra.  相似文献   
46.
Recreation carrying capacity (RCC) is one of the most important indictors used in measuring the usage limits for the forest park resources. However, the consensus has not been reached with respect to the RCC’s content and its measuring metrics. In this paper, we attempt to establish a new RCC theoretical framework based on the demand theory of the tourism product characteristics. In the process, the choice experiment and orthogonal design methods are used in questionnaire designs and the conditional Logit model is used for parameter estimates. More than 700 park visitors are surveyed for data collection at the Shenyang National Forest park of Liaoning province in China. The primary park attributes being considered encompass vegetation, coverage, water quality, number of rubbish on the park trail path, admission fees, and congestion. The carrying capacity threshold for each specific attribute is identified.  相似文献   
47.
公路突发事件应急能力评估是公路应急管理工作的基础。以公路为研究对象,采用静态与动态相结合的方法,从基础制度建设能力和应急应对能力两个维度构建公路突发事件应急能力评价指标体系。运用层次分析法和DELPHI法对系统各指标因素进行量化解析,确定各因子对公路应急系统的作用大小,并分析其灵敏度和权重因子。结果表明,应急应对能力在公路突发事件的处理中占重要地位,在基础制度建设能力中信息保障占据首要地位,其次是经费资金和应急抢通;在应急应对能力方面,事故发生前的检测预警对于事故灾害的减缓显得尤为重要,通信与信息设备状况的重要性紧随其后。  相似文献   
48.
人们对资源的忧虑,经历了一个转变过程。由可耗竭资源的有限储量所带来的紧迫感趋淡。由生态承载力的衰减所引发的负面后果日益明显。从二氧化碳排放所引出的气候变化问题,是自然生态系统容纳和消除污染排放物的能力已然不足的一个反映。通过对贯穿上述认识转变过程的经济学研究文献的梳理可知,国外在此方向上的主要分析工具是气候变化综合评估模型。该类模型的优点是把经济系统与自然生态系统集成在一起,使得对碳排放的预测具有微观基础,但也因模型复杂而处理难度较高。它的一个应用是:碳减排力度是应立即强力推进。还是可渐进强化,研究文献中围绕这一问题的争论就是以气候变化综合评估模型为基础而展开的。  相似文献   
49.
The choice between specialisation and diversification of income is driven by multiple, interacting factors, such as economies of scale and scope, risk considerations, context, and household characteristics. Using panel data from Ethiopia, we investigate the role of social capital and the covariate risk of climate change and their interaction. We find that households with greater social capital tend to be more specialised, implying that diversification and informal insurance are substitutes in the mitigation of risk. We also find that this effect is significantly weaker in regions more prone to climate change, which is consistent with the average farmer being aware that informal insurance is not an effective protection against risks that affect the entire social network. We use instrumental variable random effects estimation to account for the plausible endogeneity of social capital and we also establish that our results do not depend on the poorest and most constrained individuals in our sample.  相似文献   
50.
粮食主产区耕地健康产能评价 ——以河南省温县为例   总被引:6,自引:0,他引:6  
研究目的:探寻适合中国新时代耕地产能评价的新理论与方法,界定耕地健康产能内涵,构建评价指标体系,并应用河南省温县验证。研究方法:基于"需求—功能—维度—要素—指标"理论框架,构建耕地健康产能评价指标体系,运用综合算法、"1+X"累加模型法、图层叠加法定量评价耕地健康产能。研究结果:(1)温县耕地产能和耕地健康诊断结果地域分异特征明显,以青峰岭为界,北部耕地产能和健康状况较南部好;(2)耕地健康产能整体状况良好,乡镇间差异明显;(3)耕地健康产能结果更多取决于耕地健康诊断,主要受耕地生产环境和耕地系统弹性影响。研究结论:耕地健康产能评价指标体系和评价方法有应用性。  相似文献   
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