共查询到18条相似文献，搜索用时 140 毫秒
1.
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
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
2.
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
3.
基于小波分析的粮食产量对气候变化的响应研究——以西藏自治区为例 总被引：1，自引：0，他引：1
提取1960-2005年西藏自治区粮食单产数据,选取4个典型气象台站,以粮食耕作面积作为加权因子获取综合气象因子数据,采用小波分析方法分析粮食产量对气候变化的响应关系,并预测后期西藏自治区粮食产量的总体趋势。研究发现,西藏粮食单产、气温、光照、降水均具有明显的25 a特征时间尺度的周期性波动,粮食产量对气候变化响应密切,气温偏暖、光照偏长、降水偏多对粮食生产较为有利。趋势预测表明西藏自治区的粮食生产正由相对丰年向相对贫年转化,需引起重视。 相似文献
4.
云南省粮食供需安全状况及趋势研究 总被引：5，自引：0，他引：5
通过对云南省近18年来粮食生产与需求进行对比,定量分析了当前云南省粮食供需状况,并在此基础上通过灰色系统GM（1,1）模型预测2010～2030年粮食产量,同时参照云南省的权威人口预测数据,对未来云南省粮食供需趋势进行预测。研究表明：在未来20多年内,云南省土地提供的粮食能基本满足全省居民温饱型的粮食消费水平,距小康型粮食消费水平有一定差距,达到富裕型粮食消费水平的可能性很小。根据研究结论和目前云南省粮食供需状况,提出了相关解决云南省粮食产能安全的对策和建议。 相似文献
5.
西藏自治区居民食品消费结构与粮食对策 总被引：4，自引：0，他引：4
通过对西藏自治区700户居民抽样调查数据和有关统计资料的分析发现，西藏居民食品消费中肉类、奶类所占比重较大，高于全国平均水平。人均直接粮食消费仅269．02k，粮食消费以内地粮食为主，本地粮食在居民生活中的直接消费比重平均为42．54％；人均间接消费粮食46．02k，占粮食消费总量的13．35％，间接消费以饲料用粮为主。根据西藏人口自然增长率、居民消费结构变化和保证居民生活的基本营养，运用SEI模型分析了全区粮食供求关系，对西藏2005—2020年的粮食需求状况进行了预测。并建议西藏未来粮食政策应立足西藏实际，以发挥区域优势、促进区域经济总体发展为总目标，大力发展有西藏特色的优质青稞生产，促进全区与内地之间的互补，在本区内不宜大力强调区域粮食自给。基于此，并提出了相应的粮食发展对策。 相似文献
6.
海平面上升背景下黄浦江极端风暴洪水危险性分析 总被引：4，自引：0，他引：4
黄浦江流域是典型的风暴洪水脆弱区。随着气候变化和海平面上升,未来该区域可能遭受更为严重的灾害影响。从海平面绝对上升、构造沉降和压实沉降三个方面预测了2030 年和2050 年该区域海平面相对上升值为170 mm和390 mm。在此基础上,结合最大天文潮位值和最大风暴增水值,估算了2030 年和2050 年极端风暴洪水位将分别达到7.17 m和7.39 m。基于高精度洪水数值模型开展了2030 和2050 年两种极端风暴洪水情景模拟,结果显示黄浦江两岸地区均可能被淹没,上游地区较中下游地区受淹将更为严重。进而提出未来研究中需重点关注不确定性分析、防汛墙溃堤淹没情景分析和风暴频率—强度变化等领域。 相似文献
7.
粮食安全是国家战略安全的重要组成部分,在经济新常态下如何夯实农业基础地位、保障粮食安全成为政府与学界共同关注的命题。运用粮食产量变化系数、变异系数、空间分析方法研究了中国粮食产量时空演变格局与粮食安全问题。结果表明：2000-2003年受城镇化和工业化快速推进占用优质农田和大量青壮年劳动力进城务工的影响,粮食播种面积下降导致产量出现波动下滑;2004-2015年,粮食直补、农业税减免、基本农田保护、耕地红线等系列政策促进粮食产量实现“十二连增”。粮食作物类型时序变化表现为玉米产量大幅增长,由1990年的9 681.9×104 t增长为2015年的22 463.2×104 t,稻谷、小麦产量呈现小幅增长态势。2000-2015年中国粮食生产重心逐渐由西南向东北偏移。从各大区域对粮食总产的贡献率来看,1990-2015年南方沿海区对中国粮食总产的贡献率下降幅度最大,达-5.02%,东北地区对全国粮食总产的贡献率增幅最高,为7.75%。中国粮食产量安全区域范围在逐年增加,由2000年的11个省份增加至2015年的16个省,然而,未来粮食安全应关注粮食结构、粮食品质、食品安全、农田生态环境等方面的研究。 相似文献
8.
中国中部地区粮食安全水平及其对国家粮食安全的保障能力评价 总被引：2，自引：0，他引：2
《地域研究与开发》2015,(6)
中部地区是中国粮食安全保障基地,其产量约占全国的1/3。根据中部地区的实际,提出了中部地区粮食安全的概念,并定量确定了当中部地区粮食自给率达到112%时才能实现该地区的粮食安全。通过构建中部地区粮食安全综合指数和粮食安全保障系数,定量评价了1991—2011年期间中部地区的粮食安全水平和粮食安全保障能力。中部地区粮食安全综合指数平均值为1.016,表明研究期内中部地区整体处于粮食安全状态,但仍有7个年份该指标值低于1,表明在这些时期该区处于粮食不安全状态。除2003年中部地区粮食安全保障系数小于0外,其他年份均大于0,研究期内该系数的平均值为0.12,表明1991—2011年中部地区不但维护了自身的粮食安全,且每年至少能够提供1 763万t以上的粮食以保障中国其他区域的粮食安全。 相似文献
9.
基于最小人均耕地面积和耕地压力指数的普安县粮食安全研究 总被引：1，自引：0，他引：1
地方粮食安全是国家粮食安全的重要组成部分,耕地是粮食生产的物质基础,耕地变化必将对粮食安全产生深远的影响。文章以贵州省普安县为例,运用最小人均耕地面积耕地压力指数模型测度粮食安全状况,分析了普安县1997-2010年间粮食安全和变化特点,并运用回归分析法、指数平滑模型,对其未来10年最小人均耕地面积以及耕地压力指数进行了粮食安全预测,同时提出了保障粮食安全的建议。 相似文献
10.
以大量的数据分析了贵州省1989～2005年的耕地、人口和粮食变化情况;利用粮食平衡系数进行测算分析,分析了1989～2005年贵州省9个地市的粮食盈缺情况和粮食安全空间格局.在此基础上结合人口预测模型和时间序列平滑预测方法,预测贵州省各地市未来10 a的粮食安全状况. 相似文献
11.
Capacity for grain self-sufficiency on the Tibetan Plateau(TP) is an important basis for ensuring social stability and regional sustainability. Thus, based on county-level statistical data for population, grain production and consumption, we analyzed patterns and trends in grain supply and demand at regional, provincial, and county levels on the TP between 1985 and 2016. We applied two indices to evaluate capacity for grain self-sufficiency and found that the regional average self-sufficiency rate increased quickly by 1.97%/a since 1989, reaching 173.03% on the plateau over the period between 2010 and 2016. This indicates that grain supply in this region is able to fully meet demand. In addition, all provinces apart from Xinjiang exhibited similar increasing trends, attaining grain self-sufficiency during 2010–2016. Furthermore, 59% of counties attained grain self-sufficiency over this period, mainly distributed in southern Tibet, in the Sichuan-Tibet junction area, and in eastern Qinghai Province. A number of gaps in grain supply and demand occurred within the headwater regions of the Yangtze and Yellow rivers as well as on the Qiangtang Plateau. Grain self-sufficiency significantly increased over the study period in 36% of counties, mainly distributed in the agricultural areas of southeastern Tibet and in eastern Qinghai. Across the whole plateau, capacity for grain self-sufficiency substantially increased between 1985 and 2016, although serious spatial imbalances remain. 相似文献
12.
中国各省级行政区未来气候耗能变化可能情景 总被引：1，自引：1，他引：0
利用7个全球耦合气候模式的集成结果,得到我国2020~2029和2050~2059年气温和度日变化的可能情景。结合社会经济发展的影响,计算得到我国各省级行政区未来气候耗能变化的可能情景。结果表明:我国未来平均年总度日有显著的降低,总度日的变化有明显的地域性,西部和北方地区降低,南方地区有所增加;取暖度日普遍降低,降温度日有不同程度的增加;2020~2029年和2050~2059年度日变化空间格局相似, 2050~2059年的变化幅度大于2020~2029年;未来我国南方沿海大部分地区的气候耗能有所增加,气候耗能下降区主要分布在北方、中部和西部地区;气候耗能变化空间格局有度日变化的作用,也受社会经济发展水平的影响,同一地区的各省(区、市)具体气候耗能变化值也有较大差异。 相似文献
13.
未来中国的农业资源综合生产能力与食物保障 总被引：39，自引：3，他引：39
首先预测了包括耕地资源和非耕地资源在内的农业资源的未来食物生产能力 ;然后以不同的营养供给量为标准 ,根据人口预测方案估算了未来三个时段的食物需求量 ;最后开展需求量与生产能力的平衡分析。在耕地资源生产的粮食数量与同期需求量的平衡分析中 ,2 0 10年以小康水平的食物结构作为需求标准 ,粮食生产能力略大于粮食需求量 ,2 0 30年和2 0 5 0年以较富裕和富裕水平的食物结构作为需求标准 ,粮食生产能力已小于粮食需求量。说明依靠有限的耕地资源难以满足中国从小康生活到富裕生活过程中的食物需求。以农业资源综合生产能力为基数的供需平衡分析表明 ,未来三个时段农业资源的综合生产能力所提供的食物数量均高于同期需求量。因此必须挖掘非耕地资源的食物生产潜力 ,依靠农业资源综合生产能力才能保障中国从小康生活到富裕生活过程中的食物需求。 相似文献
14.
中国粮食生产的区域格局变化及东北商品粮基地的响应 总被引：58，自引：7，他引：51
依据近10年的统计数据和实地调研资料,运用区域差异分析方法,对中国粮食生产的区域格局变化特征及其规律进行探讨,研究表明:中国粮食产量总体呈增长态势,年均增长率为3.43%;粮食生产重心进一步由南方向北方和由东部向中部推移,北方和中部地区成为新的增长中心;粮食生产地域变化的差异明显,南北绝对差异和相对差异变化较大,八大产区和省区间变化较小。农业生产条件、技术、宏观经济环境和土地利用方式变化是粮食生产地域格局变化的主要原因。东北作为国家粮食安全战略性基地,应对全国粮食生产的地域变化趋势,必须加强商品粮基地建设。通过农业生态环境建设、农业结构调整、商品粮基地空间布局优化等举措,促进粮食生产,保障国家粮食安全。 相似文献
15.
Grain production patterns are the basis of a nation’s food security. Since China’s reform and opening-up began in 1978, China’s urbanization process, driven by rapid social and economic development, has accelerated steadily. During this time, the dietary structure of urban and rural Chinese has also changed significantly. Accordingly, grain production patterns have undergone major changes. First, traditional grain production patterns in the north and the south have changed, and the food production center has shifted toward the north. In 1980, the grain yield of southern provinces accounted for 60% of China’s total, while that of northern provinces accounted for 40%. In 2015, the grain yield of southern provinces accounted for 56% of the total, while that of northern provinces accounted for 44%. Second, grain production by regions of the country is “shrinking in the east but expanding in the central regions,” meaning that grain production in eastern coastal provinces has decreased significantly, while that in the central region has expanded. The proportions of the nation’s total grain production from the eastern, central and western regions were 38%, 36% and 26%, respectively, in 1980. These had changed to 27%, 46%, and 27%, respectively, in 2015. Third, the spatial centralization of grain production has increased. The total grain yield of 13 major grain-producing provinces and regions in the country accounted for 69.27% of nation’s total in 1980, and it had reached 76.18% in 2015, showing that the impact of major grain-producing areas on national food security has increased. The influence of rapid urbanization on grain production areas shows remarkable regional differences. As the level of urbanization has increased, build-up land occupies a large number of high-quality farmland, especially in east coastal provinces and thus the grain planting area decreased obviously. The effect of dietary structure changes on grain production patterns was evident in two ways. On the one hand, as dietary diversity has increased, total grain consumption has decreased. The reduction in the proportion of planting area for grain crops to total crop planting area dropped from 82% in 1980 to 68% in 2015, making this change in total grain consumption evident. On the other hand, the ratio of grain for human consumption declined as the ratio of grain consumed by animals increased. The reduction in the proportion of rice and wheat grown and an increase in the proportion of feed grain production (mostly maize) from 20% in the 1980s to 36% in 2015 makes this change in grain production and consumption evident. In the future, with the establishment of national functional areas for grain production, the spatial pattern of grain production will return, while the demand for feed grains will continue to increase but with the space for expansion limited. 相似文献
16.
中国南方调整水稻种植格局——一种水稻生产预先适应气候变化的选择(英文) 总被引：1，自引：0，他引：1
Rice planted in southern China accounts for 94% of the total in sown acreage and 88% of the total in production, which matters a lot to Chinese food security. However, due to the prolonged conflict between water availability and rice growth in spatial/temporal distribu-tion, rice production suffers from seasonal drought at acreage of 16%-22%, which compro-mises food production capacity and food security. Focusing on the spatial distribution of seasonal drought with rice and the practices to adapt to it, and based on an analysis of bal-anced water supply for and demand by rice at a growing season scale during 1981-2030, this paper assesses the changing seasonal drought in the process of rice production under the changing climate in the future, and identifies general rice re-cultivation options for climate change adaptation. Some conclusions can be drawn as follows. (1) Rice suggests a decline in seasonal drought, with early season rice (early rice hereafter) by 12,500 km2, middle season rice (middle rice) by 80,000 km2, and in particular late season rice (late rice) by 25,000 km2, which accounts for almost 20% of its cultivated acreage. It is indicated that due to climate change, seasonal drought in major rice producing areas tends to alleviate in general, late season rice in particular. (2) Future climate change brings about a significant impact on the spatial/temporal distribution of water resources in rice producing areas in China. Based on ’pre-designed’ adaptation actions for rice-re-cultivation, the rice cultivation pattern undergoes a significant alteration between 1981-2000 and 2001-2030. In eastern Guizhou and western Hunan, the pattern of single early plus single dry farming is changed into double cropping. In eastern Hunan, the pattern of dry cropping is changed into single early plus single dry farming. In northern Anhui, the pattern of dry farming cropping is changed into middle rice. All this is aimed at a potential adequate availability of water for rice production in the future. (3) Rice re-cultivation patterns developed in this paper help re-balance water demand and supply for rice growth using the spatial analysis tool to adapt rice growth to the changing water avail-ability from spatial perspective, and come up with rice producer-friendly re-cultivation options in response to climate change. 相似文献
17.
全球气候变化影响下中国农业产量的可持续性 总被引：11，自引：2，他引：9
气候变化的区域影响愈益成为具有挑战性的问题,尤其是气候变化对农业产量可持续性的影响已引起广泛的关注。基于全示气候变化对中国的影响和区域气候变率分析,提出了粮食气候产量形成模型,半将其应用于黄淮海地区冬小麦小分条件和产量研究,同时对全球气候变化情形下冬小麦产量的变化做出评价。 相似文献
18.
In view of food affordability and the threshold for food security, this paper has established an integrated index for assessing the vulnerability of food security in China, which is composed mainly of the balance between food supply and demand, the reserve for food security and the economic capacity for offset food demand. Six types of food security regions are identified based on the data from county-level statistics. At regional scale, China’s food security is not optimistic. Under normal conditions without the emergence of extreme disasters and decline of grain-sown areas, China’s most vulnerable areas (Type VI) account for 30.3% of the total number of counties (cities), which are unable to meet the ends by food productivity or market based measures at subsistence levels. In China, there are only 14.5% of the counties (cities) that could guarantee well-off food security through grain production (Type I) or economic measures to meet the demand by themselves (Type III). According to the different vulnerable levels of food security and its dominant forming factors, vulnerable regions of food security in China could be classified into three categories: (1) Vulnerable regions of food security dominated by natural factors (including Type IV and Type VIa), which account for 39.4% of the total number of counties (cities), mainly located in fragile ecologic zones, i.e., farming-grazing transitional zones in the marginal areas of summer monsoon, the poor hilly areas in southern China and so on; (2) Vulnerable regions of food security dominated by low ratio of grain-sown areas (including Type VIb and Type V), which account for 16.7% of the total number of counties (cities), mostly located in the developed areas in the eastern coast of China; (3) Potential vulnerable regions of food security with underdeveloped local economies (Type II), of which 57% are the main grain-surplus regions in China, mainly located in the areas of plains and basins with favorable climate. 相似文献