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561.
In 2004–05, Niger suffered a food crisis during which global attention focused on high levels of acute malnutrition among children. In response, decentralised emergency nutrition programmes were introduced into much of southern Niger. Child malnutrition, however, is a chronic problem and its links with food production and household food security are complex. This qualitative, anthropological study investigates pathways by which children are rendered vulnerable in the context of a nutritional 'emergency'. It focuses on household-level decisions that determine resource allocation and childcare practices in order to explain why practices apparently detrimental to children's health persist. Risk aversion, the need to maintain self-identity and status, and constrained decision making result in a failure to invest extra necessary resources ingrowth-faltering children. Understanding and responding to the social context of child malnutrition will help humanitarian workers to integrate their efforts more effectively with longer-term development programmes aimed at improving livelihood security. 相似文献
562.
A dynamic dose and risk assessment model is developed to estimate radiological consequences of atmospheric emissions from nuclear power plants. Internal exposure via inhalation and ingestion, external exposure from clouds and radioactivity deposited on the ground are included in the model. The model allows to simulate interregional moves of people and multi-location food supply in the computational domain. Any long-range atmospheric dispersion model which yields radionuclide concentrations in air and on the ground at predetermined time intervals can easily be integrated into the model. The software developed is validated against radionuclide concentrations measured in different environmental media and dose values estimated after the Chernobyl accident. Results obtained using the model compare well with dose estimates and activities measured in foodstuffs and feedstuffs. 相似文献
563.
安徽省耕地资源数量变化及其对粮食安全的影响 总被引:3,自引:0,他引:3
利用1978年以来30年的耕地资源统计数据,分析了安徽省耕地资源数量变化总体特征,探讨了耕地资源数量变化对粮食安全的影响。其结果表明:(1)耕地资源总量和人均耕地占有量均有呈直线递减趋势,其中耕地资源总量年均减少率为024%,人均耕地面积年均减少率为115%。(2)粮食产量总体呈增加趋〖JP2〗势,但具有较明显波动性,粮食安全仍将面临着很大挑战。(3)粮食总产量与单产水平和复种指数密切相关;而粮食总产量年变化率,则主要受耕地面积和粮食播种面积变化影响。1978年以来,耕地资源数量逐渐成为影响该省粮食产量增加的主要限制因子. 相似文献
564.
在相同接种配比(接种污泥占餐厨垃圾的质量分数为30%)条件下,研究了4种不同来源污泥(压滤污泥、厌氧污泥、曝气污泥和河底淤泥)添加或不添加缓冲剂时对餐厨垃圾厌氧发酵产氢效果的影响.结果发现,在不添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>河底淤泥>压滤污泥>曝气污泥,接种厌氧污泥的餐厨垃圾平均产氢量最高,达10.11mL(以每克挥发性固体(VS)计,下同);而添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>曝气污泥>压滤污泥>河底淤泥,接种厌氧污泥的餐厨垃圾平均产氢量也最高,为33.72 mL,且体系pH得以缓冲. 相似文献
565.
高温高饵料密度对萼花臂尾轮虫实验种群休眠卵动态的影响 总被引:2,自引:0,他引:2
探讨了在较高温度和饵料密度下实验室小批量培养萼花臂尾轮虫(Brachionuscalyciflorus)休眠卵产生的时间及变动规律.结果表明,在本实验条件下,该轮虫高温较低温时休眠卵产生得早;未见饵料密度对休眼卵的产生时间有影响;前期培养于适宜温度和饵料密度条件下的轮虫种群,产生休眠卵的数时大. 相似文献
566.
Basic scenarios of sustainable development for the world community and approaches to the problem of ensuring food security
are discussed. The conservation of agricultural resources is the key element of food security. The structure and main objectives
of agroecology are characterized in brief. 相似文献
567.
The burrowing and trophic activities of four pika (Ochotona) species proved to be reflected in the horizontal structure of the biogeocenotic cover. Zoophytochores ofOchotona daurica andO. pallasi pricei burrows correspond to previously described ameboid zoophytochores. Burrows of pikas provide for the growth of pea shrubs
(Caragana bungei, C leucophloea), with the formation of specific plant groups under their crowns and on rubble dug out by pikas. In ecosystems of placers,
zoophytochores are formed owing to the presence of pika food stores and lavatories, which are the main substrate for vascular
plants first appearing among the stones. General ecological (and successional) series characterizing the overgrowing of placers
is as follows: (1) separate spots of vegetation with poor floristic composition at the sites of pika food stores (stacklets);
(2) groups of spots and simplest complexes; and (3) complex plant communities of pika colonies. Food stores of pikas in Tuva
were analyzed. 相似文献
568.
The Public Nutrition approach, like that of Public Health, is context specific. It places an emphasis on populations rather than individuals and is inter-disciplinary in nature. Both approaches seek to understand the complex aetiology of a clinical outcome such as malnutrition within the widest possible framework. Public Nutrition uses the UNICEF conceptual framework and adapts and expands it. The authors of this article argue – through the examination of a number of case studies taken from the work of Concern Worldwide (hereafter referred to as Concern) in southern Sudan, Rwanda, Angola, Tanzania and DRC – that there are two critical constituents of the Public Nutrition approach. These are: a contextual analysis (including the use of surveillance information for programme design and advocacy) and community involvement at all stages of the project cycle. Some of the key obstacles to the adoption of the Public Nutrition approach are identified by illustrating two practical programme settings. For the Public Nutrition approach to be more widely used, the authors recommend a number of key strategies including the further dissemination of case studies and the clarification of the scope and boundaries of the approach. These strategies will enable Public Nutrition to evolve both as a practical programme framework as well as an academic discipline. 相似文献
569.
农业结构调整对全国粮食安全的影响分析--以粮食主产区为例 总被引:9,自引:0,他引:9
基于粮食主产区农业发展及其结构调整中面临的问题分析,指出近5年来导致我国粮食产量持续下降的主要原因在于农业结构调整。大规模的“压粮扩经”趋势若不能有效控制,必将对国家粮食安全带来冲击。对2005-2010年我国粮食需求及粮食主产区占全国粮食产量比重进行测算.提出不同粮食自给率下国家粮食安全对粮食主产区粮食生产的目标要求。粮食主产区具有满足国家粮食安全产量需要的生产潜力。 相似文献
570.
全新型生态工业园区的工业共生链网结构研究--新疆石河子国家生态工业(造纸)园区的设计分析 总被引:11,自引:0,他引:11
本文以新疆石河子国家生态工业(造纸)园区的设计为例.运用产业生态学理论,深入系统地分析了生态工业园区的系统构成、工业共生关系以及生态工业链网结构.为全新型生态工业园区的设计及其运行提出了切实可行的建议。 相似文献