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Effect of cropland occupation and supplement on light-temperature potential productivity in China from 2000 to 2008 总被引：2，自引：0，他引：2
There are more people but less land in China,so food safety has always been a most important issue government concerned.With continuous population increase,economic development and environment protection,cropland occupation and supplement are unavoidable.It not only leads to the variation of cropland area,but also makes the light-temperature potential productivity per unit area different due to regional climate differentiation,therefore impacts the total potential productivity and food output eventually.So,it is necessary to analyze the climate differentiation between occupation and supplement cropland areas and to study its impact on total potential productivity,which is significant to reasonably develop natural resources and instruct agricultural arrangement.This study firstly discussed the variation and distribution of occupation and supplement croplands in China from 2000 to 2008,then analyzed the climate differentiation between occupation and supplement cropland areas and its effect on light-temperature potential productivity.The results demonstrate:1) From 2000 to 2008,the cropland variation presented occupation in the south and supplement in the north,but overall decreased.Supplement cropland was mainly from ecological reclamation(77.78%) and was mainly distributed in Northeast China and Northwest China with poor climatic and natural conditions.Occupation cropland was mainly used for construction(52.88%) and ecological restoration(44.78%) purposes,and was mainly distributed in the Huang-Huai-Hai Plain,and the middle and lower reaches of the Changjiang(Yangtze) River with better climatic and natural conditions.2) The climate conditions were quite different in supplement and occupation cropland areas.The annual precipitation,annual accumulated temperature and average annual temperature were lower in the supplement cropland area,and its average po-tential productivity per unit was only 62% of occupation cropland area,which was the main reason for the decrease of total potential productivity.3) Cropland occupation and supplement led to the variation of total potential productivity and its spatial distribution.The productivity decreased in the south and increased in the north,but had a net loss of 4.38315×107 t in the whole country.The increase of cropland area was at the cost of reclaiming natural forest and grassland resources,and destroying natural ecological environment,while the decrease of cropland area was mainly due to a lot of cropland occupied by urban-rural construction,which threatened the sustainable use of cropland resources. 相似文献
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2005-2008年中国耕地变化对区域生产潜力的影响 总被引：3，自引：0，他引：3
我国人多地少,粮食安全问题一直是国家关注的头等大事。而耕地资源与粮食生产能力是保障粮食安全的基础,因此,研究中国耕地变化对区域生产潜力产量的影响具有重大的现实意义,可以为国家相关决策提供科学依据。本研究基于2005-2008年最新的气象观测数据和卫星反演数据,并结合2005、2008年耕地数据及其变化数据,从耕地资源的数量变化与质量特征两方面,研究2005-2008年耕地变化对我国全境内光温生产潜力的影响。研究结果显示:在耕地的变化过程中,光温生产潜力增加区与减少区产量变化不对等:增加区增加785.14万t,减少区减少2543.61万t,净减少1758.47万t;增加区与减少区光温生产潜力单产不对等:增加区平均光温生产潜力单产为11.89t/hm2,减少区平均光温生产潜力单产为20.99t/hm2,后者约为前者的2倍;增加区与减少区空间分布不同:增加区主要分布在新疆、黑龙江、内蒙古、宁夏、青海等西北、东北地区,生态用地开垦是其增加的主要原因,占77.25%,减少区主要分布在江苏、安徽、山东、广东等黄淮海平原、长江三角洲、珠江三角洲地区,建设用地占用耕地是其减少的主要原因,占69.20%。 相似文献
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