中国县域耕地与农业劳动力变化的时空耦合关系

利用1996 年、2000 年和2005 年中国县域耕地与农业劳动力数据，基于GIS 技术和模型方法，分析了县域耕地面积与农业劳动力变化态势及其时空耦合特征。研究表明：① 县域耕地面积和农业劳动力变化均呈先增后减态势。1996-2000 年，耕地总量、劳动力数量分别增长2.70%和1.40%；2000-2005 年，耕地总量、劳动力数量分别减少1.51%和8.18%。②“胡焕庸线”是刻画中国耕地和劳动力变化格局的重要分界线。沿此线带状区域内因退耕还林造成耕地快速减少，而农业劳动力转移滞后；其西北部区域耕地快速增加，农业劳动力也在增长；其东南部区域耕地明显减少，而农业劳动力减少速度更快，二者呈现协调态势。③ 耕地非农化进程中县域劳动力转移效率呈下降趋势。1996-2000 年和2000-2005 年，全国分别有447 个和505 个县域的耕地减少和劳动力转移呈良性变化，90%的县域劳耕弹性系数(LFEC) 的中位数分别为4.58 和2.97。④ 基于SOM自组织特征映射神经网络聚类方法，可将1996-2005 年中国县域耕地与劳动力变化的耦合特征划分为9大类型区。多情景模拟分析表明，2005-2015年的LFEC趋势值为2.55。

Spatio-temporal Coupling Relationship between Farmland and Agricultural Labor Changes at County Level in China

Cultivated land and agricultural labor force are two core elements for promoting agricultural production and sustainable rural development. During the process of rapid urbanization and industrialization in China, numerous agricultural labors transferred to non-agricultural sector and a huge proportion of farmland was converted to construction land, in particular, these changes were spatially uneven. Theoretically, coupling relationship should be found between farmland and agricultural labor change. The overspeed of farmland conversion or agricultural labor transfer may affect the sustainability of agricultural production and rural development. Policy implications may arise from systematic analysis on spatio-temporal coupling relationship between agricultural labor transfer and farmland conversion. Based on county-level statistical data of farmland and agricultural labor, this paper gives an exploratory study in this area, by using GIS technology and mathematical modeling approach. The results showed that: (1) both the total amount of farmland and agricultural labor of the 1914 studied counties increased from 1996 to 2000 and then went through a process of reduction. The amount of farmland and agricultural labor increased by 2.70% and 1.40% from 1996 to 2000, and then decreased by 1.51% and 8.18% from 2000 to 2005, respectively. (2)“Hu Huanyong Line” which links Aihui and Tengchong cities, is an important dividing line in depicting China's spatial pattern of farmland conversion and agricultural labor transfer. Within the ribbon region along this line, farmland decreased drastically due to Grain for Green Project, however, the agricultural labor transfer lagged behind severely. In the region to the northwest of ribbon region along the HU Line, the reclamation of reserve resources caused a substantial increase of farmland, and the amount of agricultural labor grew steadily. In the region to the southeast of ribbon region along the HU Line, farmland was converted to construction land generally and agricultural labor decreased rapidly. Coupling relationship between farmland conversion and agricultural labor transfer could only be found in the third region. (3) During the study periods from 1996 to 2000 and from 2000 to 2005, 447 and 505 counties experienced a benign agricultural transfer in the process of farmland loss, respectively. Labor-farmland elastic coefficient (LFEC) of 90% of these counties ranged with a median of 4.58 and 2.97, respectively, which means that the efficiency of agricultural labor transfer decreased during the process of rapid farmland loss. (4) By developing a clustering method based on Self-organization Mapping (SOM) Neural Network on the software platform of ArcGIS and MATLAB, the coupling relationship between farmland conversion and agricultural labor change was divided into nine regional types, and also the control orientation for each region was put forward. Multi-scenario simulation analysis predicted that the trend value of LFEC during 2005-2015 was 2.55, and this could be a standard parameter for coordinating the relationship between farmland conversion and agricultural labor change in the next 10 years in China.