Evolution characteristics and decomposition of driving factors on rural residential land based on decoupling theory and LMDI model

In order to study the coupling relationship between rural population and rural residential land area change and promote the economization and intensification level of rural residential land, in this paper the Tapio decoupling model was introduced to reveal the decoupling degree of rural population-land change. From the perspective of urban and rural demographic shift, the factors decomposition model for rural residential land expansion was established. The logarithmic mean Divisia index (LMDI) was adopted to quantitatively analyze the influencing factors accounting for the changes in rural residential land area. The change of rural residential land area was decomposed into 4 main driving effects including rural residential land intensive use effect, urban-rural population structure effect, urbanization effect and total population effect. The addition decomposition method was used to measure the magnitude of 4 driving effects. The rural residential land area of China (1996-2016) and 31 provinces or municipalities (2000-2016) were taken as example. The results show that China has experienced rapid urban-rural transformation in the past few years. Rural population continues to decrease, presenting a 30.7 percent decline. But in the meantime, the total area of rural residential land increases continuously. The changes in rural residential land area among different provinces (municipalities) varied obviously, and overall the eastern and western regions indicated a greater growth. The relationship between rural population and rural residential land change is uncoordinated, and rural residential land tends to be more extensively utilized. From the decoupling index of China and 31 provinces or municipalities, the decoupling relationship between rural population and residential land area change were mainly characterized by strong negative decoupling. The degree of negative decoupling in the eastern and western regions was more serious than that in the central areas. What's more, the degree of negative decoupling is generally deteriorating. The values of 4 driving effects were measured from 1996-2016. The results indicated that the scale of rural residential land in China increased by 2.020×105 hm2 from 1996 to 2008 including a decrease of 116.833×105 hm2 caused by urban-rural population structure effect, and the increase of 33.497×105, 71.813×105, 13.544×105 hm2 for rural residential land intensive use effect, urbanization effect and total population effect, respectively. Additionally, during 2009-2016, the scale of rural residential land in China increased by 7.275×105 hm2. The rural residential land intensive use effect, urbanization effect and total population effect caused the increase of 36.689×105, -68.271×105, 32.164×105, 6.692×105 hm2, respectively. Among 4 driving effects, the urban-rural population structure effect was stronger than the others. The contribution of 4 driving effects to the change in rural residential land area in different periods performed differently. The value of urbanization effect was greater than that of rural residential land intensive use effect during 1996-2008, but after 2009, the rural residential land intensive use effect gradually exceeded the urbanization effect, and become the dominant factor caused the increase of rural residential land. Therefore, strengthening the planning and management of rural residential land, gradually promoting rural residential land consolidation, and actively exploring the exit mechanism of rural residential land may be effective measures for improving the intensification level of rural land use. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.