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81.
In areas of war and armed conflict it is difficult to get trustworthy and coherent information. Civil society and human rights groups often face problems of dealing with fragmented witness reports, disinformation of war propaganda, and difficult direct access to these areas. Turkish Kurdistan was used as a case study of armed conflict to evaluate the potential use of satellite images for verification of witness reports collected by human rights groups. The Turkish army was reported to be burning forests, fields and villages as a strategy in the conflict against guerrilla uprising. This paper concludes that satellite images are useful to validate witness reports of forest fires. Even though the use of this technology for human rights groups will depend on some feasibility factors such as prices, access and expertise, the images proved to be key for analysis of spatial aspects of conflict and valuable for reconstructing a more trustworthy picture.  相似文献   
82.
从微观农户角度分析了干旱、农业旱灾和农户旱灾脆弱性的成因。文章认为,自然降水不足或与作物需求匹配不均是造成农业干旱的动力,农户对干旱的应付能力不足是导致干旱成灾的原因。这种应付能力既受区域水资源可利用量的限制,也与农户的作物种植结构、灌溉支付能力、风险认识和对农业的依赖程度有关。农户旱灾脆弱性既与农业干旱有关,又受到人均资源和收入、种植和消费结构、生态环境质量、政策、市场价格等多重因素的作用。最脆  相似文献   
83.
In the Kranzberg forest near Freising (Germany) a novel “Free-Air Canopy O3 Exposure” system has been employed for analysing O3-induced responses from sub-cellular to ecosystem levels that are relevant for carbon balance and CO2 demand of 60-year-old beech trees. The below-ground ectomycorrhizal community was studied in two-fold ambient O3 concentrations (five cores per sampling) and in a control plot with an ambient O3 concentration (four cores per sampling). Five samplings were taken throughout two vegetation seasons (2003 and 2004). Types of ectomycorrhiza were determined by their morphological, anatomical and molecular characteristics and quantified by counting. The total number of mycorrhizal fine roots was higher at the fumigated plot as compared with the control site. The numbers of ectomycorrhizal types at the fumigated and control plots were 28 and 26, respectively. Cenococcum geophilum was present in all soil cores at all sampling times with a significant increase in abundance under ozone-fumigated trees. Other mycorrhizal types present at higher abundance at the fumigated than at the control plot were identified as Russula densiflora, R. fellea, R. illota, Tuber puberulum, Lactarius sp. 2 and Russula sp. 2. Some mycorrhizal types were present exclusively at the fumigated plot (Fagirhiza fusca, F. setifera, Lactarius acris, Piceirhiza nigra and Russula sp. 1). A possible ecological role for the abundant types of ectomycorrhiza and their putative application in bio-indication is discussed.  相似文献   
84.
Helen Young 《Disasters》2000,23(4):277-291
This paper introduces and discusses the main themes and issues arising from the workshop 'International Public Nutrition in Emergencies: The Potential for Improving Practice'.
Good co-ordination within the nutrition sector of the international humanitarian response system has led to a range of achievements in recent years. Major constraints to improving programme impact remain, however, including misconceptions about the scope of nutrition among the wider humanitarian system, which tends to give it a narrow focus on malnutrition and feeding people. In contrast to this limited view, the Public Nutrition approach brings a more broad-based emphasis to assessing and responding to nutritional problems in emergencies, and takes into account the wider social, economic and political causes of malnutrition.
Six case study presentations illustrated the various components of a Public Nutrition approach, including in-depth assessment, analysis and tailoring programmes accordingly. Additional presentations considered the nature of vulnerability, the concept of Public Nutrition, the responsibilities for addressing nutritional problems and some of the operational tools and frameworks in current use.
Participants agreed on the necessity of raising levels of awareness and understanding among all actors in the humanitarian sphere about the impact of their actions on nutrition. Strategies for achieving this included developing better multi-sectoral working relationships and also strengthening relationships with donors and key decision-makers in the humanitarian system. Other related strategies included institutional learning, training and capacity building, particularly in relation to institutions based in developing countries and building upon initiatives such as the Sphere Project, which has successfully brought together the various actors within the humanitarian system in order to improve quality of response.  相似文献   
85.
Karen Peachey 《Disasters》2000,23(4):350-358
Unlike other population groups, the rights, needs and contributions of older people in developing countries are not well understood. With the absence of information about how to assess the nutritional status and vulnerability of older people, HelpAge International joined forces with the London School of Hygiene and Tropical Medicine in the early 1990s to launch a research programme. Seven years later some of the basic questions can now be answered but there remains much more to do.
Although older people are increasingly acknowledged as a vulnerable group in emergencies, NGO responses often fail to meet their needs. The question is whether there are real difficulties in service adaptation or whether ageism is one of the greatest barriers to the provision of appropriate services for older people.  相似文献   
86.
We propose a method for the appropriate assessment of adverse effects of roads in compliance with the European Union Habitats Directive. The method incorporates an analysis of ecological risk of edge effects by the proposed roads with the related increase in accessibility. The method was tested on 30 km of planned forest roads inside an 8,000-ha reserve included in two Natura 2000 sites. As a result, the cumulative effect of 19 road segments was judged as not significantly affecting the integrity of the sites, although they made accessible an extra 314 ha. On the basis of the accessibility calculation, 20 ha of land were set aside from forest exploitation as a mandatory mitigation measure. The method objectively determined the cumulative adverse effects, enabled comparison of plan revisions and alternatives and proved to measure direct and indirect significant effects with a realistic effort in terms of field survey and geographic information system processing.  相似文献   
87.
温室气体上升导致的全球气候变暖问题不容忽视,增加森林碳汇和木质林产品碳储是缓解温室效应的有效途径。根据森林碳汇功能与林产品碳储功能的关联理论与模型,推导和改进包括森林子碳库、土壤子碳库及木质林产品子碳库在内的林业碳库核算模型及方法,以实现目标碳从森林碳库向木质林产品碳库的过渡与转移。基于气候变化背景下森林-林产品产业链的发展现状,构建包括森林子碳库和林产品子碳库的复合一体化林业碳库模型,使之为中国林业碳库的计量与评价提供判据。首先,对包含森林子碳库和木质林产品子碳库在内的世界林业碳库的发展现状进行探讨,归纳和比较国内外主流的关联林业碳库评估方法模型,从而对中国林业碳库模型的构建提供理论背景支持和逻辑方法支撑。其次,分析现有中国林业碳库评估存在的优势和弊端,找出适合中国林业特点的国家碳库创新评估路径,运用政府间气候变化专门委员会指定的生产法的思路,通过分析目标碳在林产品产业链生产、加工等过程中的流入和支出,提出创新中国林业碳库的模型构想并对其系统内涵进行分析。最后,赋予中国林业碳库系统模型数学表达,分析其数理结构并进行逻辑演绎,在森林子碳库和木质林产品子碳库两个复合链式体系下构建中国林业碳库系统测度模型(ForestProducts Carbon Model/FPCM)。  相似文献   
88.
庐山不同森林植被类型土壤特性及其健康评价   总被引:2,自引:0,他引:2  
土壤作为森林生态系统的一个重要因子,评价森林土壤健康状况对森林健康的维护经营以及森林系统功能的发挥具有重要意义。在系统调查和分析庐山8种森林植被类型土壤特性的基础上,评价指标分别从物种多样性以及不同的森林土壤特性中进行筛选,包括物种多样性系数、枯落物层厚度、腐殖质层厚度、土层厚度、容重、粘粒含量、有机质、p H值、阳离子交换量、全氮、水解氮、有效磷、速效钾、磷酸酶活性等指标,基于SPSS19.0软件对所获得数据进行差异性检验和相关分析,确定各项指标的权重,应用合适的土壤健康评分函数,将测得的指标值转换为对应指标的分值,最后通过加权综合法,计算其土壤健康指数,并对不同森林植被类型土壤健康状况进行评价。结果表明,8种森林植被类型下最终的土壤健康指数大小排序为:针阔混交林(0.78)常-落混交林(0.72)灌丛(0.69)常绿阔叶林(0.67)落叶阔叶林(0.64)竹林(0.59)马尾松林(0.53)黄山松林(0.46)。  相似文献   
89.
Resilience as a frame is increasingly appearing in grant funding, news stories, academic journals, and organization missions. Across these sites, resilience is positioned as an ability to cope, characterized by bouncing back, regaining control, and reducing vulnerability to change. How did resilience come to be understood in these terms? What are the problems with resilience's frames and the practices that produce them? How might we become resilient differently? Using a Foucaultian archaeology, I examine sites and practices that produce resilience as discourse. I analyze resilience's origins in biophysical sciences, systems perspectives that define ways of knowing, visual models that constrain the emergence of new ideas, and persistent dialectics that narrowly order relationships within the world. I propose changes in the discourse for more affective and ecological modes of becoming resilient.  相似文献   
90.
The assessment of aquifer vulnerability is a very important task, especially in agricultural areas because the quality and availability of groundwater affects both the sustainability of agriculture and the quality of life. In this study, an integrated approach is considered, with the use of the generic and agricultural DRASTIC models as well as a geographic information system (GIS), to assess groundwater vulnerability in the agricultural area of Barrax, in the province of Albacete, in Spain. Seven parameters—depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone media, and hydraulic conductivity of the aquifer (DRASTIC)—have been considered as weighted layers to enable an accurate groundwater risk mapping. The results of the generic DRASTIC model indicated very low vulnerability to contamination for Barrax groundwater due to limited urban and industrial development in the wider area. However, agricultural activities impose pressure to groundwater resources and the results of the agricultural DRASTIC model show that 6.86% of the study area is characterized by very high, 2.29% by high, 47.28% by medium, 38.28% by low, and the remaining 5.29% by no vulnerability to groundwater contamination. The distribution of nitrate concentration in groundwater in the area under study is quite well correlated with the agricultural DRASTIC vulnerability index. Sensitivity analysis was also performed to acknowledge statistical uncertainty in the estimation of each parameter used, to assess its impact, and thus to identify the most critical parameters that require further investigation. Depth to water and impact of vadose zone are the parameters that had the most noticeable impact on the generic DRASTIC vulnerability index followed by the soil media and topography. In contrast, the agricultural DRASTIC method is more sensitive to the removal of the depth to water parameter followed by the topography and the soil media parameters.  相似文献   
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