Identifying the key regions of potential arable land restoration from the perspective of in-out balance

An accurate and rapid identification is one of the most important steps to optimize the spatial pattern of land, particularly for the key areas of cultivated land restoration potential in recent years. The "in-out balance" of cultivated land can then be fully implemented to ensure national food security. Taking Wenshang County, Jining City, Shandong Province of China as the research area, this study aims to establish a raster scale identification model of cultivated land restoration potential under the perspective of "in-out balance". The "three adjustments" data was also selected to integrate the four dimensions of agricultural production suitability, new cultivated land restoration potential, land cluster contiguity, and economic development level. A geographic information system (GIS) spatial analysis was used to quantitatively measure the effect scores of each factor. The multi-factor spatial overlay was then used to comprehensively evaluate the cultivated land restoration value. The high-value cluster area was finally identified as the key area using the natural breakpoint. As such, the key area of cultivated land restoration potential was quantitatively identified to explore the spatial distribution pattern. The results showed as follows. 1) There was a high suitability of agricultural production, where the suitability index was between 0.33 and 0.79. It infers that the zonal differentiation decreased gradually from the east to the west, indicating a significant regional difference. Engineering restoration was the main potential type of cultivated land restoration. Specifically, the woodland was widely distributed in the recoverable land, accounting for 72.89%. There was an excellent degree of land agglomeration and contiguity on the whole. The high and middle contiguity areas accounted for 71.85% with a distribution trend of "low in the middle and high around". The spatial differences were observed in the level of economic development. The distribution characteristics were complementary to the restoration potential of newly cultivated land and land contiguity. 2) The comprehensive evaluation showed that the 23 key areas of cultivated land restoration potential were identified with a total area of 56.31 km², which were distributed in the central, southern and east-west edges of the county. The key areas were widely distributed in the study area. Therefore, the improved model can be expected to identify the key areas of the main agricultural production areas mainly in the plain. The finding can also provide a scientific basis for the selection of cultivated land restoration and renovation projects, as well as the preparation and implementation of cultivated land "balance in and out" plans. Anyway, the sustainable utilization of cultivated land can be promoted to optimize the territorial spatial pattern under the system of "balance in and out" of cultivated land.