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381.
The government of Zimbabwe launched the Fast Track Land Reform Programme (FTLRP) in 2000 as part of its ongoing land reform and resettlement programme which aims to address a racially skewed land distribution. Its goal has been to accelerate both land acquisition and redistribution, targeting at least five million hectares of land for resettlement. This paper investigates the impact of the FTLRP on its beneficiaries' perceptions of land tenure security, and how these subsequently impacted soil conservation investments. Evidence suggests that the programme created some tenure insecurity, which adversely affected soil conservation investments among its beneficiaries. We find support for the contention that households make land‐related investments to enhance security of tenure. The results underscore the need for the government of Zimbabwe to clarify and formalize land tenure arrangements within the programme.  相似文献   
382.
通过建立大气湍流扩散模型,结合大气、地形条件等环境基本资料和危化品的性质,计算出危化品泄漏突发事件的应急防护范围,为人群撤离和监测布点监控,提供安全保障。  相似文献   
383.
Reducing the impact of drought and famine remains a challenge in sub‐Saharan Africa despite ongoing drought relief assistance in recent decades. This is because drought and famine are primarily addressed through a crisis management approach when a disaster occurs, rather than stressing preparedness and risk management. Moreover, drought planning and food security efforts have been hampered by a lack of integrated drought monitoring tools, inadequate early warning systems (EWS), and insufficient information flow within and between levels of government in many sub‐Saharan countries. The integration of existing drought monitoring tools for sub‐Saharan Africa is essential for improving food security systems to reduce the impacts of drought and famine on society in this region. A proactive approach emphasizing integration requires the collective use of multiple tools, which can be used to detect trends in food availability and provide early indicators at local, national, and regional scales on the likely occurrence of food crises. In addition, improving the ability to monitor and disseminate critical drought‐related information using available modern technologies (e.g., satellites, computers, and modern communication techniques) may help trigger timely and appropriate preventive responses and, ultimately, contribute to food security and sustainable development in sub‐Saharan Africa.  相似文献   
384.
The rural economic situation in China-with a living standard mostly at subsistence level-lags far behind the prosperous development in the cities and coastal areas. To balance this disequilibrium, comprehensive concepts and endeavors are necessary keeping in view all-not just economic-interests and needs that contribute to lively rural identities. In this context the role of agriculture, where still 50% of the Chinese population are working, will be newly defined, and sustainability concepts can help to find a readjusted position within the Chinese economy focusing on environmental health and food safety as main targets of political and other supporting measures. Within the SUCCESS project, a Concept of Sustainable Agriculture was developed and it drafts one conceivable relation between the exposure to natural resources and economy and tries to find new answers to the broad range of rural challenges in China. It is a qualitative model and, therefore, not always fully applicable, but in the concrete situation of villages, it shows possible directions of sustainability-oriented development by considering the typical local potentials. In the Chinese context that means identifying the different functions of agriculture-the well-known and the hidden-to make them explicit for the Chinese public and therewith to give them new significance. The article is based on a 3-years study within the EU-China Project SUCCESS with field research in four Chinese rural communities. It analyzes the agricultural sustainability potential of these selected villages against the background of massive structural changes within the next 20 years in rural China. Starting from the current agricultural reality, based on a qualitative analysis of the actual situation, local potentials and needs towards sustainable production and marketing are identified, and possible functions of the Chinese agriculture are formulated for the future.  相似文献   
385.
Inorganic arsenic is a chronic exposure carcinogen. Analysis of UK baby rice revealed a median inorganic arsenic content (n = 17) of 0.11 mg/kg. By plotting inorganic arsenic against total arsenic, it was found that inorganic concentrations increased linearly up to 0.25 mg/kg total arsenic, then plateaued at 0.16 mg/kg at higher total arsenic concentrations. Inorganic arsenic intake by babies (4-12 months) was considered with respect to current dietary ingestion regulations. It was found that 35% of the baby rice samples analysed would be illegal for sale in China which has regulatory limit of 0.15 mg/kg inorganic arsenic. EU and US food regulations on arsenic are non-existent. When baby inorganic arsenic intake from rice was considered, median consumption (expressed as μg/kg/d) was higher than drinking water maximum exposures predicted for adults in these regions when water intake was expressed on a bodyweight basis.  相似文献   
386.
民用机场空防安全的风险管理研究   总被引:4,自引:1,他引:3  
主要通过对民用机场空防安全存在的风险从作业人员、设备和设施、环境、管理等4方面进行识别;以系统的观点为基础,结合相关法规,建立空防安全风险评价指标体系;运用AHP方法对民用机场的空防安全进行风险研究,并通过研究、分析计算数据,查找、预测民用机场空防系统中存在的一些不足和缺陷;针对机场保安、管理、规章制度等方面的不足,结合中国民航和民用机场的现状及实际情况提出相应的建议性措施,以期达到最低事故率、最少损失和最优的安全投资效益。  相似文献   
387.
大型社会活动安全风险评估指标研究   总被引:3,自引:1,他引:2  
在对大型社会活动特点及其活动增长趋势分析的基础上,通过对大型社会活动典型伤亡事故的统计,将事故发生直接原因归纳为突发自然灾害、设备设施故障、管控措施失误、疏散设施不符合要求、人为事件和其他因素6类;根据风险管理理论,针对大型社会活动安全风险,从人-机-环-管安全系统工程的观点出发,以准确反映大型社会活动的本质特征和事故预防与控制为目标、尽可能量化为原则,提出具有4个一级指标、9个二级指标和24个三级指标的大型社会活动安全风险评估指标体系和评估依据,并对周边环境、人群密度、疏散速度及人群状况指标进行量化分级。  相似文献   
388.
辽东湾入海污染物调查及海域水质安全分析   总被引:2,自引:0,他引:2  
对辽东湾入海污染源、污染物总量及近海海域水质调查、监测,并对其水质安全进行了分析、评估。其污染物主要来自沿海各城市排入近海的工业污水、生活污水、入海河流携带污染物,海水养殖过程中产生的废水、残留饵料、排泄物等以及沿海港口码头的作业船舶和海上航行作业的机动船等泄漏、倾废;氮、磷营养盐过度排放导致赤潮频繁发生,危及海洋生物的生存;水质有机污染严重致使海产养殖病害,生物物种减少;重金属、人工合成的难降解的有机物等有害有毒的污染物沉积近岸海底,对近海水质安全形成威胁。  相似文献   
389.
我国危险化学品企业搬迁方案研究   总被引:1,自引:0,他引:1  
概要地对我国现有危险化学品企业安全防护距离不足的现状进行分析,提出危险化学品企业搬迁工作实施的基本原则,探讨危险化学品企业搬迁范围的确定、厂址的解决、资金的分配、政策的制定和长效机制的建立等问题。建议搬迁企业在政府的统一规划下,坚持以人为本,坚持安全生产和可持续发展的原则,在搬迁中提高技术含量和社会形象,增强市场竞争力。针对我国危险化学品企业的特点提出了一套搬迁方案和步骤。论文的研究成果将为各地政府指导当地危险化学品企业进行科学规划,对待搬迁的危险化学品企业实现安全有效搬迁及健康发展提供了有益参考。  相似文献   
390.
社会安全事件空间分布研究   总被引:4,自引:2,他引:2  
在讨论社会安全事件空间分布特点的基础上,简要介绍用于空间自相关性分析的主要算法。重点对基于密度聚类(DENCLUE,density-based clustering)的算法的基本原理、过程及利用积分均方误差MISE进行精度检验等方面进行阐述。将该算法用于社会安全事件空间分布研究领域中的犯罪热点区域探测。分析结果表明,与以往分析方法相比DENCLUE算法具有抗噪声能力强、能生成任意形状的聚类等特点,可有效地用于社会安全事件空间分布区域的研究,但也发现算法在格网边长的确定及窗宽长度选择方面的不足,有待进一步研究。  相似文献   
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