中国县域人均粮食占有量的时空差异及驱动因素

SPATIAL-TEMPORAL PATTERN AND ITS DRIVING FORCES OF PER CAPITAL GRAIN POSSESSION IN CHINA

以全国县域为研究单元,基于2004年和2014年各县统计数据,采用ESDA、重心迁移、GWR等方法对县域人均粮食占有量的空间格局进行测定,并分析人均粮食占有量区域差异的空间异质性及变化的驱动机制。结果表明:2004~2014年,全国各县域粮食的人均占有量呈现总体上升的趋势,人均粮食占有量的重心在10a间由西南向东北转移,且南北方向迁移的幅度大于东西方向迁移的幅度。2004年全国县域人均粮食占有量冷热点分布相对分散,东北地区是全国唯一的热点区,冷点区分布在沿海地区,2014年热点区相比于2004年有所缩小,冷点区则有所扩大。影响人均粮食占有量变化各因素的重要程度在空间上差异明显,其重要程度由大至小依次为:人口数量>第三产业比重>城市化率>第二产业比重>人均GDP。

Grain supply- consumption balance is an important indicator for national food security. Per capital grain possession is a major indicator in studying the supply-and-demand equilibrium of grain. Agricultural statistics at county- resolution level for the period of 2004-2014 in China was collected and the GIS spatial analysis technique as well as other tools such as Moran＇s/, Getis-Ord and gravity model were introduced to describe the spatial changes of per capita grain possession at county level. Geographically weighted regression （GWR） model was used to explore the driving factors of per capita grain possession. The results showed that： First, per capita grain possession showed an overall trend of rise over the period of 2004-2014. The gravity center of per capita grain possession transferred from the southwest to northeast. Second, per capita grain possession at county level in China showed a strong trend of positive spatial natural correlation, and the similar areas cluster in space. The county-level of internal per capita grain possession spatial disparities have been gradually widened. Spatial pattern of hot spots and cold spots changed significantly during the past 20 years. In 2004, the per capita share of grain in the country was relatively scattered, and the northeast region was the only hot area in the whole country. In 2014, hot spots were still in the northeast, but somewhat smaller than in 2004. Third, the driving factors of different regions showed localization characteristic of no-stationary intercourse. The importance degree was as follows： population〉 tertiary industrial output〉 urbanization rate〉 secondary industrial output〉 per capita GDP.