Spatiotemporal differentiations of arable land use intensity — A comparative study of two typical grain producing regions in northern and southern China

Abstract

Faced with rapid urbanization, using the arable land intensively has become more popular in China, which has sparked heated discussion about the necessity of evaluation of the arable land use intensity. However, few practical researches have been done to estimate the arable land use intensity quantitatively and comparably. Based on this consideration, the method of Emergy Analysis was used to evaluate the arable land use intensity (LUI) from a perspective of unified data dimension, and the method of Dominance Index was used to discuss the key contributors to LUI. With data obtained from 2007 to 2015, two typical major grain producing regions—Shandong Province in northern China and Dongting Lake Zone in Southern China were taken as the study areas. The result showed that the two areas experienced common increasing tendency of LUI, whereas a structural difference existed in this tendency: Shandong Province showed an increase of agro-machinery with a synchronous reduction of pesticide, fertilizer, mulching film, agro-machinery and irrigation, whereas Dongting Lake zone increased the use of pesticide, fertilizer, mulching film, agro-machinery and irrigation with a unique decrease of labor force. Secondly, the spatial heterogeneity of LUI among different prefecture-level cities in Shandong Province enlarged, whereas Dongting Lake Zone kept a stable spatial distribution of LUI. In addition, compared with the undeveloped prefecture-level cities, the developed ones in Shandong Province experienced a slower increase of LUI, whereas Dongting Lake Zone showed a complete reverse result. Thirdly, the Dominance Index (DI) of fertilizer and irrigation showed a large downtrend in Shandong (both decreased by nearly 18%), which indicated that the contribution of fertilizer and irrigation to the LUI had been weakened, whereas the DI of all production materials hold steady in Dongting Lake Zone. To further improve the efficiency of arable land management, this research put forward some suggestions such as transferring the dependency on using physical capital to technical capital on arable land, focusing more on pre-evaluation of LUI, and adjusting arable land use pattern to local development conditions etc., which would help to realize the sustainable-intensive arable land use in the future.