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1.
基于空间模型的全球粮食安全评价   总被引:7,自引:1,他引:6  
在综合考虑自然、社会和经济等因子对粮食安全影响的基础上,选择了人均粮食占有量和人均GDP两个指标空间显性评价全球粮食安全状况。为此,本研究构建了3个模型,即空间EPIC模型、作物选择模型和IFPSIM模型,分别模拟作物单产、作物播种面积和作物价格。利用构建的评价框架和模型,以网格大小为6分弧度的地理单元为评价对象,选择水稻、玉米、小麦和大豆等4类全球主要作物类型,以2000年为初始年份,对未来2020年的全球粮食安全状况进行了评价。结果表明,到2020年,多数南亚国家和非洲国家,由于其人均粮食占有量和人均GDP两个指标值都显著降低,粮食供应不足和贫困一起将可能导致该区域存在粮食危机和饥饿风险。对于其他区域,日益增长的粮食需求可以通过本区域的粮食生产自给予以满足,或通过外部购买或粮食进口得到满足,总体上不存在粮食安全问题。为保障未来粮食安全,一方面要保护耕地数量和质量、防止土壤退化、增加资本投入、进行技术创新和升级,提高粮食综合生产能力,保障粮食的有效供给;另一方面加大农业补贴,切实提高农民收入,保障农民利益,增强农业购买力。同时,大力改善粮食流通和农产品贸易体制,通过外部市场来调节粮食供给;积极应对气候变化,提高农业生产对气候变化的适应能力,保证粮食生产的稳定。  相似文献   

2.
Soil erosion threatens long-term soil fertility and food production in Q’eqchi’ communities native to the Sierra Yalijux and Sierra Sacranix mountain ranges in the central highlands of Guatemala. Environmental factors such as steep topography, erodible soils, and intense precipitation events, combined with land subdivision and reduced fallow periods as a consequence of population growth, contribute to severe erosion and strain soil resources. The preservation of the region's cloud forests hinges on enhancing production of staple crops through agricultural intensification while maintaining soil fertility through implementation of soil conservation measures.  相似文献   

3.
农业工业化和“去地化”的生产模式、不透明的流通过程以及膨胀的消费欲望致使饮食系统危机不断,其可持续性成为全球尺度的挑战。当前饮食系统的可持续性研究面临尺度问题,涉及从全球地方的目标转化,以及从地方到全球的经验反馈两个方面。首先,全球尺度的可持续目标宏大包容,但是对地方尺度的差异性缺乏关照。其次,部分西方国家的可持续实践垄断了经验表达,过于重视社区等微观尺度而忽略了其他尺度的潜在作用,引发“尺度陷阱”。本文深入剖析中国、巴西、南非的饮食系统内部各类参与者的可持续性建构,提出全球和地方可持续饮食系统互动的尺度逻辑:① 从全球到地方的目标转化需要兼顾地方差异。中国、巴西、南非各自生成优先的可持续目标,分别针对食品安全、食物原真性和食物浪费、结构性的食物匮乏等问题。这些目标之间充满张力和博弈,不能等同替代。② 从地方到全球的经验反馈需要打破西方经验赋予的微观尺度的优越性,转向跨尺度的实践。发展中国家的可持续实践路径的要义在于发挥饮食系统各类参与者的能动性,调动资源形成有效的跨尺度行动网络。③ 发展中国家的经验表明尺度本身是方法,而不是目的,每个具体的可持续目标与适切的尺度方法匹配。有必要研究建议挖掘多元、差异的可持续模式,更加有针对性地促进当地乃至全球饮食系统的可持续发展。  相似文献   

4.
This article aims to make a contribution to current debates in the literature on food access by describing a mixed-methods approach to study the access to food in one rural community in Cuba. Each of the forty households in our study was asked to complete a detailed food diary in which they indicated what they ate and where they acquired each of the ingredients that they used for a full week. Although in Cuba the state plays a central role in organizing the distribution of food items, this method revealed a much more complex web of rural food access. By addressing alternative networks of food access and informal social relations, we aim to show how the use of food diaries, in combination with qualitative data from interviews and participant observation, can provide detailed insights in the complex processes and networks of food access.  相似文献   

5.
中国食物安全基础的定量评估   总被引:16,自引:1,他引:16  
食物安全水平受粮食生产和供给能力、食物结构的多样化以及居民的收入水平或获取维持生命所需食物的能力等因素共同作用和影响。本文从食物安全的内涵出发,依据评价指标选取原则,选定了与食物安全密切相关的评价指标,包括粮食自给率、食物消费水平及居民消费水平等,构建了食物安全可持续性综合指数模型,计算了1950~1998年我国食物安全可持续性综合指数,对我国食物安全可持续状况进行了单因子和多因子综合评价。结果表明:在50年代我国处于食物基本安全状态,60~70年代处于食物不安全状态,80年代初期及至90年代已进入食物安全阶段。从60年代开始食物安全水平逐年提高,80年代以来进入持续良性发展阶段。  相似文献   

6.
中国粮食安全脆弱区的识别及空间分异特征   总被引:8,自引:2,他引:6  
殷培红  方修琦 《地理学报》2008,63(10):1064-1072
从粮食获取能力和粮食安全保障阈值的角度, 综合考虑粮食供需平衡、粮食安全储备、 经济补偿能力等因素, 构造综合评价指标-粮食安全保障的财政压力水平, 以粮食安全保障 费用不超过地方财政收入水平的25%作为可接受水平, 共识别出6 个不同类型的粮食安全区。 在没有重大灾害事件发生和现有粮食播种面积不变的前提下, 全国有14.5%的县(市) (1 级和3 级粮食安全区) 能够通过粮食生产或者经济补偿能力保障小康水平的粮食安全。全国29.4% 的县(市) 属于2 级粮食安全区, 其中57%的地区是中国的主要余粮区, 约占全国主要余粮区 中的72%, 因财政收入低、人口密度大, 不能负担庞大的小康水平粮食安全储备费用。中国 粮食安全最脆弱的地区(6 级区) 占全国县(市) 总数的30%, 不具备温饱水平粮食生产能力和 经济补偿能力, 主要包括两类地区: ① 夏季季风区边缘地带的农牧交错带及秦岭地区, 以及 南方贫困的丘陵地区属于“资源型粮食短缺地区”; ② 广西、广东南部以及东部沿海地区等 富裕地区属于“结构性粮食短缺地区”, 过低的粮食自给率已影响到粮食安全应急保障能力。  相似文献   

7.
粮食作为自然生态系统与社会经济系统的关联点,能够有效地揭示极端干旱事件对自然-经济-社会复合生态系统影响的过程和机理。以粮价异动为切入点,通过粮价通胀指数和“无透雨”的持续时间,分析农业旱情及其对粮食生产的影响,对1637—1643年华北地区极端干旱事件中的粮食安全进行深入剖析。结果显示:华北地区无透雨天数超过150 d,年降水量与5—9月降水量的距平值均≤-30%,水分异常短缺,土壤严重失墒,危及粮食生产安全。因此,降水量距平值≤-30%是华北地区粮食生产安全的临界阈值。此次极端干旱事件是历史同类事件之最,连续无透雨日数最长,地表径流枯竭记录最多,水资源的短缺导致伴生灾害相继发生,超过生态系统的忍耐极限,粮食生长期缩短,减产歉收,绝产绝收,粮食供给链条断裂。粮价通胀指数最低9.50,最高26.70;货币发行与粮食供给失衡,通货膨胀严重,粮价飞涨,市场倒闭,粮食安全体系崩塌,自然-经济-社会复合生态系统发生质变成为历史必然。  相似文献   

8.
中国食物供给能力分析   总被引:9,自引:0,他引:9  
王情  岳天祥  卢毅敏  杜正平  辛晓平 《地理学报》2010,65(10):1229-1240
从中国各类型生态系统(农田、草地、水域) 的实际的食物生产能力出发,结合进出口产品中的食物部分,得出全国实际的食物供给能力,根据食物营养成分表中的转化率,将各类食物折算成人类生存所需的3 大营养成分(热量、蛋白质、脂肪) 的产量来表示,并利用ArcGIS 进行草地和农田食物供给的空间分析。以2004 年为例,中国实际食物供给能力为:热量1.601×1015 kcal,蛋白质6.163×107 t,脂肪2.717×107 t。其中,中国内陆生态系统实际可供给热量1.454×1015 kcal,蛋白质4.996×107 t,脂肪2.074×107 t,分别达到了陆地生态系统生产潜力的32.46%、38.33 %和41.12%,内陆生态系统食物供给还有较大的增长余地。在小康水平下,中国的食物热量、蛋白质、脂肪分别可以供养人口19.12 亿,20.84 亿和11.03 亿人,按照2010 年营养目标和2020 年全面小康目标,热量和蛋白质的供给已经较为充足,而脂肪的供给有所不足,今后需要注重油脂作物的种植和生产。结果还表明:中国的食物供给能力中,农田占据了绝大部分,不过比例有下降的趋势,从1998 年的84.66%,下降到2004 年的74.72%;草地和水域生态系统所提供的食物所占比例分别为4.83%~5.80%、6.02%~7.51%,波动较小;净进口食物所占比例逐年增长,1998 年仅为4.04%,2004 年增加到13.82%。通过平衡模型计算,在温饱、小康、富裕水平下,2004 年中国可以供养的人口分别为:15.34 亿,15.00 亿和14.11 亿,这表明,如果能够优化种植结构,合理配置植物性食物向动物性食物转化比例,均衡营养消费结构,中国实际食物供给较为充足。  相似文献   

9.
This paper presents a scenario-based assessment of global future food security. To do that, the socio-economic and climate change scenarios were defined for the future and were linked to an integrated modeling framework. The crop yields simulated by the GIS-based Environmental Policy Integrated Climate (EPIC) model and crop areas simulated by the crop choice decision model were combined to calculate the total food production and per capita food availability, which was used to represent the status of food availability and stability. The per capita Gross Domestic Product (GDP) simulated by IFPSIM model was used to reflect the situation of food accessibility and affordability. Based on these two indicators, the future food security status was assessed at a global scale over a period of approximately 20 years, starting from the year 2000. The results show that certain regions such as South Asia and most African countries will likely remain hotspots of food insecurity in the future as both the per capita food availability and the capacity of being able to import food will decrease between 2000 and 2020. Low food production associated with poverty is the determining factor to starvation in these regions, and more efforts are needed to combat hunger in terms of future actions. Other regions such as China, most Eastern European countries and most South American countries where there is an increase in per capita food availability or an increase in the capacity to import food between 2000 and 2020 might be able to improve their food security situation.  相似文献   

10.
基于空间模型的全球粮食安全评价   总被引:3,自引:1,他引:2  
This paper presents a scenario-based assessment of global future food security. To do that,the socio-economic and climate change scenarios were defined for the future and were linked to an integrated modeling framework. The crop yields simulated by the GIS-based Environmental Policy Integrated Climate (EPIC) model and crop areas simulated by the crop choice decision model were combined to calculate the total food production and per capita food availability,which was used to represent the status of food availability and stability. The per capita Gross Domestic Product (GDP) simulated by IFPSIM model was used to reflect the situation of food accessibility and affordability. Based on these two indicators,the future food security status was assessed at a global scale over a period of approximately 20 years,starting from the year 2000. The results show that certain regions such as South Asia and most African countries will likely remain hotspots of food insecurity in the future as both the per capita food availability and the capacity of being able to import food will decrease between 2000 and 2020. Low food production associated with poverty is the determining factor to starvation in these regions,and more efforts are needed to combat hunger in terms of future actions. Other regions such as China,most Eastern European countries and most South American countries where there is an increase in per capita food availability or an increase in the capacity to import food between 2000 and 2020 might be able to improve their food security situation.  相似文献   

11.
虚拟水战略背景下的中国粮食生产空间布局优化研究   总被引:1,自引:0,他引:1  
首先,用人均农村人口粮食产量指标定量表征我国粮食生产空间布局现状,发现我国粮食生产空间布局存在"北方多、南方少,中间多、两边少"的特点,主高值区位于东北和内蒙古一带,次高值区由河南、安徽、山东、江苏、湖南、江西和重庆等中西部省份组成;主低值区为东南沿海一带,次低值区是由西北和西南诸省组成的广大地域。然后,为探究虚拟水战略背景下我国粮食生产的理想布局模式,提出区域粮食生产优势度的概念,分析其影响因素,运用定量评价模型计算各省级区域的粮食生产优势度。发现区域粮食生产优势度有2个高优势度带和2个低优势度带,且高优势度和低优势度区呈带状相间分布。最后,构建粮食生产布局调整指数作为我国不同区域粮食生产优化调整的依据,分类给出了区域粮食生产调整的方向。  相似文献   

12.
我国食物安全研究进展及展望   总被引:5,自引:1,他引:4  
保障我国食物安全是我国一切建设发展的前提和基础。在我国农业基础资源日益紧缺以及加入WTO 的 国情下, 食物安全面临着新的机遇与挑战。本文回顾了食物安全概念的演变过程, 综述了我国在自然基础资源与食 物安全、食物安全现状及其评价、国际贸易和经济全球化对食物安全的影响以及食物安全预警和管理等方面的研 究进展, 并对未来我国食物安全研究进行了展望。研究表明: 今后我国食物安全研究应在以下方面需要加强: 在研 究内容上, 不仅重视食物数量保障, 更应注重食物质量安全、食物资源可持续利用和综合食物安全风险评价与预警 等方面; 在研究视角上, 不仅重视宏观食物安全研究, 更应重视微观食物安全; 在研究方法和手段上, 应当充分运用 现代科学技术, 如网络技术、空间模拟技术以及3S 技术等, 进一步加强综合食物安全的定量和动态研究。  相似文献   

13.
土地资源约束下的北京食物供给潜力与优化(英文)   总被引:1,自引:1,他引:0  
全球气候变化所带来的极端天气的频繁发生,水资源短缺情况下的农业用水的不断减少和伴随着人口增长与社会经济发展所引起的耕地面积下降,正在严重影响着世界范围内的食物安全。近年来由于食品价格的迅猛增长而导致的食品危机正在引起人们对增加地方食物供应的普遍关注。城市作为对食品安全更为敏感的地区,更是首当其冲受到食品危机的影响,城市一方面由于城市化快速发展,带来城市人口膨胀和消费多样性要求,从而形成需求的大幅增加,另一方面有由于城市周边耕地面积的不断减少,农业生产空间受到压缩,农业生产能力减弱,降低了城市的自我食品供给,引起自给率明显下降。如何保持供需之间的平衡,保障城市食品安全,成为亟需研究的问题。本文提出以食物足迹的概念,来衡量城市所间接消耗的土地资源,并以此为工具,以自给率为条件,来求得满足一定自给率条件下食物供给的空间对应格局。通过分析30年来北京食物足迹以及食物自给率的年际变化,得出结论:北京食物足迹从1981年的1.18万km2增加到2010年的2.94万km2,而自给率整体下降较多,蔬菜、水果、谷物及油脂类的自给率从1981年的59.3%、35.8%、37.3% 和 13.1% 下降到2010年的39.0%、27.0%、6.7% 和2.2%,可以看出蔬菜仍能保持相当的自给率,因此提高蔬菜自给率是增强城市自给能力的最佳选择。最后,以60%的蔬菜自给率为目标,提出了两种情景,包括完全以耕地为来源的空间应对格局,以及屋顶农业参与下的空间应对格局。  相似文献   

14.
Currently, the topic of food waste and its environmental impacts is attracting increasing attention among academic researchers. Based on an investigation of restaurants in Beijing, this study analyzes the quantities, structures, characteristics and costs of the agricultural resources related to food waste in the catering industry in Beijing. The results show that: (1) The average food waste per capita per meal is about 75.02 g (raw) for food away from home among Beijing urban residents, which means that about 10.52% of the food is wasted. (2) According to the quantitative ranking of different categories of food waste, vegetable is the most wasted, followed by meat, aquatic products, and grains. The foods in the other categories are wasted much less. (3) Food waste is affected by the restaurant type, as well as the number, gender, age, education level, and consumption motivation of the consumers. (4) Based on the estimated food waste per capita, about 417.92 thousand tons of food is wasted annually at the consumption stage in the catering industry in Beijing. This food waste amount is equivalent to approximately 765.53 tons of cereals which are wasted, and this represents 79.66% of cereals production and 13.15% of cereals consumption in Beijing. Estimated by the required land use, this amount of food waste means that the total production of approximately 166.12 thousand ha of arable land is being wasted in Beijing.  相似文献   

15.
This article explored the relationship between the local food environment and walkability in the socioeconomically diverse, inner-ring suburbs of metropolitan Detroit. The availability and cost differentials of food were surveyed using a modified version of the Nutrition Environment Measures Survey for Stores (NEMS–S), and a geographic information system–based method was designed to map walkability relative to licensed food retail establishments. Results showed that minority communities lack access to fresh produce and nutritionally adequate foods, which is compounded by limited mobility. By incorporating local-based economic incentives, low-income communities can better align neighborhood goals of obtaining nutritionally adequate food (and other services) with economic opportunity.  相似文献   

16.
张鹏岩  庞博  何坚坚  郭依  朱连奇 《地理科学》2017,37(9):1392-1402
粮食是社会经济发展的重要保障。运用耕地、粮食安全测度模型对2005~2014年河南省粮食安全状况进行评估。结果表明:2005~2014年,农民种粮积极性上升10%,耕地压力指数下降71%,农民经济收益上升 13%,耕地重心向西南移动。 不同指标对耕地生产力的贡献率具有差异性。2005~2009年粮种比对耕地生产力的贡献率最大,2010~2014年贡献率发生转移,粮食播种面积单位产量对耕地生产力的贡献率最大;10 a间,粮种比的贡献(69.77%)相对粮食单产的贡献(39.28%)更能促进河南省耕地生产力的提高。 耕地压力受到自然、社会等多方面因素影响。各指标间相关关系较强,种粮积极性与农民耕地保护能力的二者呈现负相关关系。  相似文献   

17.
马铃薯“主粮化”战略要求在不挤占三大主粮的前提下提升国家马铃薯种植面积和产量。已有关于马铃薯种植空间布局的研究缺少定量支撑的相关优化证据。本文结合统计数据分析中国马铃薯的消费结构及其消费量的变化趋势,应用ARMA模型预测中国2022—2040年马铃薯年均需求量。结合耕地空间分布数据和马铃薯县域种植面积数据,应用GAEZ模型以适宜性等级作为优先级对未来中国马铃薯种植布局进行县域尺度空间推演,提出未来中国马铃薯县域尺度的种植空间布局优化方案。结果表明:① 1961—2019年,中国马铃薯的总消费量由1290万t增加到了9152.5万t,其中食用消费结构变化最为显著。② 2022—2040年,中国马铃薯年均需求量为1.10亿t,基本适宜及以上程度马铃薯种植区域共计5423万hm2,种植其中532万hm2可满足相应消费需求。③ 基于适宜度指数的未来中国马铃薯最优生产布局为东北一季作区、华北一季作区、西北一季作区和西南一二季混作区(包含55个县级区域)。建议坚持整体推进与重点突破相统一的原则,推动马铃薯种植布局优化升级。研究结果能够为中国粮食安全政策制定和马铃薯种植空间布局提供理论参考。  相似文献   

18.
The purpose of this article is to identify food deserts using a geographic information system (GIS)-based multicriteria decision-making (MCDM) approach in the city of Tehran. We have found that, compared to technocratic methods, GIS-based MCDM and taking into account people or their agents' opinions in the food deserts analysis leads to different results. Whereas measuring food deserts based on the distance to large retail food stores indicated that a large part of the northern neighborhoods of Tehran do not have access to large food stores, identifying the food desert through the GIS-based MCDM approach revealed that northern neighborhoods of Tehran have relatively good access to healthy, affordable food. In addition, results indicated that individual factors have a more effective role than environmental factors in food accessibility. Food accessibility analysis revealed that more than 26.6 percent of Tehran's people (2,049,796) are living in very low and low food accessibility areas. Accordingly, to achieve a relatively healthy and inclusive food environment, establishment of a food council, development of mobile food markets and farmers' markets, extension of public transport, enhancement of food literacy, and community-based development of small full-service grocery stores, especially in southern and western sections of Tehran, should be pursued. In addition, addressing Tehran's food desert issues would be incomplete without due attention to the wider political and economic environment.  相似文献   

19.
江西省食物供给时空格局   总被引:1,自引:0,他引:1  
江西省是我国的粮食大省,对未来国家粮食安全具有重要意义.本文分析了江西省1980-2005年的各类食物产量变化趋势,并结合食物营养转化式和不同生活水平的食物营养需求标准,对江西省食物营养供给总量和供需平衡进行时空格局分析,得出:①稻谷产量约占江西粮食总产量的95%,并一直保持增长趋势,而油料、大豆、薯类和甘蔗产量199...  相似文献   

20.
综述广东省绿色食品发展存在的问题 :(1)绿色食品生产的地区分布不平衡 ,规模小 ,品种结构不合理 ;(2 )绿色食品“产前、产中、产后”的生产与管理技术落后或缺乏 ;(3)资金投入与科技投入不足 ;(4 )宣传力度不够 ,人们的绿色食品意识淡薄 ;(5)绿色食品生产的“比较优势”未能充分体现。同时 ,提出了一系列的发展对策。  相似文献   

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