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我国人均粮食变化的地理研究 总被引：10，自引：1，他引：10
人均粮食占有量是反映粮食供给水平的重要指标，本文分析了我国人均粮食占有量变化的阶段和地理特征，并探讨了其与粮食增产的关系，对因地制宜调控人粮关系有一定参考价值。 相似文献
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中国人口分布的土地资源限制性和限制度研究 总被引：5，自引：0，他引：5
以人口分布的土地资源限制性评价为核心,建立土地资源限制性与限制度模型,从全国、分省、分县等三个不同尺度,全面评估近10年中国人口分布的土地资源限制度及其时空耦合规律,定量揭示中国人口分布的土地资源限制程度及其空间格局与变化规律。结果表明：① 1949年以来中国的土地资源承载力趋于增强; 2010年与2000年相比,人口分布的土地资源限制度由42.87下降到34.50,土地资源限制度在降低。② 分省的人粮关系趋于好转,大多省份人口分布的土地资源限制度处于较低水平; 2010年与2000年相比,分省人口分布的土地资源限制度整体呈降低趋势。③ 2000-2010年分县粮食盈余地区在增加,人口超载地区在减少,人粮关系趋于改善; 2010年和2000年相比,基本不受土地资源限制的分县单元由60.27%增至70.63%,基于人口分布的土地资源限制度整体较低,且近10年呈降低趋势;土地资源限制度整体上东部强于西部、南部强于北部、泛黄河流域强于长江流域。 相似文献
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甘肃省河西地区二十一世纪初水土资源开发战略 总被引：2，自引：2，他引：2
在分析河西近４０年水土资源开发利用和生产力发展过程的基础上，探讨了资源利用趋势与开发潜力。水土利用现已接近资源的极限，畜牧业的发展具有超载增长的特征，逐步缓解水土矛盾、畜草矛盾、人田矛盾将是本世纪末至下世纪初的艰巨任务，资源利用率的提高决定着未来的发展。 相似文献
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耕地与粮食安全战略：藏粮于土,提高中国土地资源的综合生产能力 总被引：54，自引：0，他引：54
耕地资源的数量和质量是粮食生产的基本保证,耕地资源安全是中国粮食安全的关键。我国耕地安全是基本态势是：人均耕地不足、后备资源有限、地域分析布失衡。世界粮食态势同亲不容乐观,中国粮食问题全球瞩目。要保证我国耕地与粮食安全,从根本上解决“藏粮于库”问题,有必要实施“藏粮于土”计划,全面提高中国土地资源的综合生产力。其主要战略内容是：切实保护耕地,建立国家级耕地保护区;实施土地整理,提高土地资源利用率, 相似文献
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民以食为天,应认真抓好粮食生产。湖南自然条件优越、粮食种植历史悠久、物质基础牢固,发展粮食生产潜力极大。因受生产规模大,产品质量低;发展速度快,年际波动大;水稻突出,旱粮较少;发展水平较高,地区差异明显;粮食积压较多,发展形势严峻等矛盾的制约,生产潜力未能充分发气掘。为此,建议作好粮食转化工作,扩大销售市场;重视智力投资,加强农业科技推广工作;提高单产,建设好商品粮基地;运用区划成果,调整粮食生产分布。 相似文献
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作为资源环境承载力的重要组成部分,土地资源承载力关注区域土地资源对其发展的限制作用,其已有两百多年的发展历史。本文对土地资源承载力的起源和发展进行了简单回顾,土地资源承载力的发展逐渐由土地资源的人口承载力向综合承载力发展,其关注重点也由最初的人—粮关系转向土地—社会经济活动关系。相应的,土地资源承载力的研究方法也逐渐由静态、单要素研究走向动态、多要素研究。具体而言,农业生态区位法(AEZ)、系统动力学(SD)、生态足迹(EF)以及土地资源综合评价法是近年来最具代表性的土地资源承载力研究方法。作为传统的土地资源承载力研究对象,人粮关系在现代土地资源承载力研究依然占据重要地位,因为粮食是土地资源最重要的限制性因素,同时也是区域人口与土地资源平衡的重要判据,特别是对于人口大国而言。传统土地资源承载力研究方面应该加强对耕地资源、食物消费水平估计的精确性以提升评价结果质量水平,同时科技的发展、生活方式对区域土地资源承载力的影响亦是一个值得关注的要点。近年来,土地资源综合承载力研究成为一个热点问题,其不仅扩充了土地资源承载力的研究领域,同时也试图在一个开放系统下讨论土地资源对区域可持续发展的限制性,但其在承载机制、理论与实际相结合等领域的研究仍需要进一步加强。 相似文献
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耕地与粮食安全战略:藏粮于土,提高中国土地资源的综合生产能力 总被引：9，自引：0，他引：9
耕地资源的数量和质量是粮食生产的基本保证 ,耕地资源安全是中国粮食安全的关键。我国耕地安全的基本态势是 :人均耕地不足、后备资源有限、地域分布失衡。世界粮食态势同样不容乐观 ,中国粮食问题全球瞩目。要保证我国耕地与粮食安全 ,从根本上解决“藏粮于库”问题 ,有必要实施“藏粮于土”计划 ,全面提高中国土地资源的综合生产力。其主要战略内容是 :切实保护耕地 ,建立国家级耕地保护区 ;实施土地整理 ,提高土地资源利用率 ;建设基本农田 ,提高土地资源生产效率 ;建立小区平衡机制 ,提高农业资源区域配置效率 ;立足全部国土 ,挖掘非耕地食物资源生产潜力。 相似文献
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吴嘉本 《云南地理环境研究》2000,12(1)
黄土高原包括陕、甘、宁、晋、内蒙5省(区)109个县市(区),土地面积27.68×104km2,人口3 000万人.是我国人口、资源、环境矛盾最集中、治理难度最大的区域之一,该区农业生产的核心问题是粮食供应不足,解决好粮食开发与生态环境改善的矛盾是该区社会经济可持续发展的关键.因此,黄土高原粮食生产发展前景以及提高粮食生产的关键技术受到社会各界的广泛关注. 相似文献
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吴嘉本 《云南地理环境研究》2000,12(1):93-95
黄土高原包括陕、甘、宁、晋、内蒙 5省 (区 ) 1 0 9个县市 (区 ) ,土地面积 2 7.6 8× 1 0 4km2 ,人口 30 0 0万人。是我国人口、资源、环境矛盾最集中、治理难度最大的区域之一 ,该区农业生产的核心问题是粮食供应不足 ,解决好粮食开发与生态环境改善的矛盾是该区社会经济可持续发展的关键。因此 ,黄土高原粮食生产发展前景以及提高粮食生产的关键技术受到社会各界的广泛关注。上官周平、彭珂珊等研究者在承担国家科技攻关项目的基础上 ,撰写的《黄土高原粮食生产与持续发展研究》一书 ,对黄土高原地区作了大量的细致研究和调查工作 ,积累… 相似文献
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Research on ecosystem service consumption not only helps to reveal the utilization intensity and management level of the ecosystem in Guilin, but it also provides a scientific basis for ecosystem investment, trade, subsidies and taxation by the Guilin government departments. Based on household survey data of urban and rural ecological consumption, the physical quantity accounting method is adopted for multivariate statistical analyses, such as analysis of variance and multiple comparison. This analysis reveals the differences and changes in the consumption level, consumption structure and consumption pattern of the main ecological products in Guilin among the various counties. The results fit into four main themes. (1) The annual per capita consumption of the main ecological products in Guilin varies either extremely significantly or significantly among the counties, but the consumption level of ecological products varies according to the type of products. There are significant or extremely significant differences in the annual per capita consumption of cereals, melons and fruits, pork, poultry, beef and mutton, fresh eggs and milk between urban and rural residents. (2) There are extremely significant differences in the annual per capita consumption of fruits, pork, poultry, beef and mutton, fish, fresh milk and vegetable oil among urban residents in different counties. There are also extremely significant differences in the annual per capita consumption of cereals, pork, poultry and alcohol among rural residents in different counties, and significant differences in the annual per capita consumption of fresh eggs and milk. The consumption level of ecological products by urban and rural resident varies with the type of products. (3) The ecological consumption patterns of all counties in Guilin mainly follow the “cereal + vegetable + fruit + meat” pattern for urban residents and the “cereal + vegetable + meat” pattern for rural residents (except for the rural residents in Pingle, which show the “cereal + vegetable” pattern). The consumption structure of urban residents is better than that of rural residents. (4) There is a large gap between the ecological consumption of urban and rural residents in Guilin and China's recommended standards, except for cereals and meat. The main problems are excessive meat intake, and insufficient intake of dark vegetables, fruits, eggs, milk and fish. Therefore, we should make full use of forestland, grassland, water and other resources in the area, and vigorously develop fishery, fruit and vegetable production and herbivorous animal husbandry to meet people's ecological needs for dark fruits and vegetables, eggs, milk and fish in Guilin City. 相似文献
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本文从长江产业带持续发展建设的要求出发,针对能源生产、消费和供需平衡存在的主要矛盾与问题,提出并论证了产业带未来能源资源的合理开发方向及规模、缓解能源运输矛盾的途径和上中下游能源开发方向与重点。 相似文献
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基于组合预测法、生产函数和笔者前期关于气候变化对西藏粮食产量定量影响的工作,对考虑气候变化影响的未来西藏县（区）级尺度粮食供需平衡状况进行预测。结果表明：① 西藏粮食产量较高的区域集中在一江两河等河谷地带,西藏粮食需求量较大的地区主要在人口较多的县市,未来肉类消费增加将会消耗更多的饲料用粮。② 西藏粮食供需平衡状况南北分异明显,南部河谷地区相对较好,北部羌塘高原较差。③ 当前西藏不能实现考虑口粮、饲料粮、工业用粮、种子用粮和损耗5种需求总和的粮食供需平衡,全区自给率为70.58%,2030年和2050年分别下降至62.59%和53.55%。虽然西藏总需求不能完全自给,但仍能保障口粮自给。④ 气候变化整体上对自给率为正面影响。到2030年和2050年,气候变化将使自治区粮食自给状况提升2.45%和2.09%。研究有助于掌握未来西藏粮食安全状况,规划农业布局,以期保障边疆粮食安全、促进高原农业可持续发展。 相似文献
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城乡交错带人地系统的特征及其演变机制分析 总被引：28，自引：2，他引：26
城乡交错带位于城市与乡村交互作用的地带,是我国２１世纪人地关系最为紧张的地区。从区域的角度,揭示城乡交错带人地关系地域关系的特征,分析其动态演变机制,对该地区合理开发利用资源,协调人地矛盾,实现社会经济的可持续发展具有指导意义。 相似文献
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西北地区的退耕规模、粮食响应及政策建议 总被引：19，自引：0，他引：19
退耕还林(草)是西北地区生态环境建设的重大举措,但退耕必然会对的粮食生产带来直接影响。基于全国土地利用详查的分县数据,研究认为:(1)按照法律规定,大于25度的陡坡耕地必须无条件地退耕。仅此一项,西北地区就必须退耕153.6×104hm2,占现有耕地的9.2%,粮食减产为71.2×104t,占1996年粮食产量的2.2%,对全区人均粮食占有量的影响很小;(2)在保证人均耕地0.1hm2前提下对大于15度的坡耕地退耕,则退耕面积可达347.8×104hm2,超过现有耕地的1/5;对应的粮食减产为234.5×104t,是1996年粮食产量的7.3%,甘肃、陕西和青海的粮食减产比例都在1/10左右,退耕带来的直接粮食减产效应是显而易见的。最后针对西北地区的退耕规模及其粮食响应,提出了两条政策建议 相似文献
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城市拓展对资源消耗的影响程度分析——以长春市为例 总被引：2，自引：1，他引：1
构建脱钩状态模型和响应程度模型,通过定量研究1995~2010年长春市城市拓展对资源消耗的影响程度,得到以下结论:①长春市城市拓展与资源消耗总体呈现"双增长"特征,城市快速拓展导致的资源消耗及资源环境压力不断增大;②长春市城市拓展与资源消耗始终处于"相对脱钩"状态,且资源消耗增长速度随着城市拓展呈先相对下降、后又相对提升的趋势。在城市拓展规模保持总体稳定增长的情况下,资源消耗变化是影响二者脱钩状态与脱钩程度演化的关键因素;③随着长春市城市拓展规模的不断扩大,其对资源消耗增长的影响程度持续增大,进一步说明城市拓展作为资源消耗的驱动力,其变化是导致长春市城市拓展对资源消耗影响程度增大的重要推动因素。 相似文献
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河北南部地区资源、环境、发展初析 总被引：3，自引：0，他引：3
河北南部地区山前平原区农业气候条件适于夏玉米的生长 ,黑龙港地区适于棉花的生长。本区水资源匮乏 ,地下水超采严重。浅层地下水超采模数为 8.0 1× 1 0 4 m3/( km2 ·a) ,深层地下水为 2 .5 8× 1 0 4 m3/( km2·a)。全区水资源利用的综合边际效益以廊坊市最高 ( 2 6.68元 /t) ,保定市最低 ( 1 4.85元 /t) ,两者之比为 1 .80。区内地下水降落漏斗与地面沉降等环境地质灾害频繁 ,1 998年浅层地下水漏斗区面积为 0 .5 4× 1 0 4 km2 ,深层地下水为 1 .5 9× 1 0 4 km2。地下水、粮食和蔬菜受到农药残留、过量化肥的污染。本区 2 0 1 0水平年外流域调水将占可供水量的 2 3.9% ,但缺水率仍达 36.2 %。若全区通过发展工程节水 (提高综合节水率 3.2 % )、实施适水种植 (冬小麦播种面积下调 7% ) ,利用水分胁迫处理 (减少一次灌溉 )等节水措施 ,则比 1 999年节水 1 7.2 %。 相似文献
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We study the changing volumes and costs of the energy resources available in the coming century as a result of exploration, technical progress, and consumption. The most reliable and well-documented information involves fossil fuels, which account for nearly 80 percent of the energy mix today. Known and presumed resources are fairly well ranked by cost, and we can estimate future developments. We present two consumption scenarios: the more contrasted reference case and the ecologically driven case presented by the World Energy Council at its last congress (1992). Our scenarios take into account the twofold goal set forth at the Rio summit: to achieve sustainable development and to minimize the climatic effects of pollutant emissions.We show that the most cost-effective mineral resources, including uranium, will run out only gradually in the next century according to these hypotheses. As a result, marginal cost will grow relatively slowly. However, we presuppose a tough policy on curbing consumption and using renewable sources of energy.We point out the need for better cost ranking of energy saving and energy switch possibilities. Additionally, the ecological impact and cost of corrective measures will have to be evaluated. We believe that the medium- and long-term difficulties will stem chiefly from the contradiction between low energy prices and the commitments required. The danger of geopolitical tension will remain a serious concern. 相似文献
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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