Spatial differentiation pattern and correlation factors of "non-grain" cultivated land in mountainous counties

Abstract: "Non-grain" of cultivated land refers to the planting conversion from food crops into cash crops or others. The disorderly expands of "non-grain" cultivated land can greatly threat to regional food security. It is a high demand to scientifically measure the degree and spatial distribution pattern of cropland "non-grain". In this study, the spatial differentiation characteristics of cropland "non-grain" were identified to reasonably control the influencing factors in the mountain counties using spatial correlation analysis. The land use data was first collected from the Xinfeng County of Jiangxi Province in China, according to the Third National Land Survey. The correlation factors and formation mechanism were then revealed for the spatial pattern of cultivated land "non-grain" using the correlation analysis and spatial econometric model.The research results showed that: 1) The "non-grain" rate of cultivated land was 30.28% in the study area, of which the "non-grain" area of plantation structure and the "non-grain" area of agricultural industry structure were 6 601.94 and 7 679.98 hm2, with "non-grain" rates of 13.84% and 16.44% respectively. There was outstanding spatial heterogeneity for the distribution of cropland "non-grain" in different topographic areas. Specifically, the alpine hilly areas mainly showed the "non-grain" of agricultural industry structure, whereas, the low mountain hilly areas showed the "non-grain" of cultivated land cultivation structure. 2) There was the agglomerative pattern for the spatial distribution of cultivated land "non-grain". The "non-grain" of planting structure was highly agglomerative in the central low hill and hill areas, whereas, the "non-grain" of agricultural industry structure was highly agglomerative in the eastern and northwestern high mountain and hill areas. 3) Some factors (such as the average plot size, the distance to water sources, and the density of rural road networks) posed positive effects on the "non-grain" production. The "non-food" production also received the inhibiting effects from the decision making on the permanent protection of basic farmland and grain production functional zones. 4) Since there was a spatial diffusion effect of the "non-grain" production, it is necessary to clarify the use and cultivation status of transferred cultivated land, in order to avoid the destruction of the cultivated layer of cultivated land. According to the natural resource conditions and industrial development, the control strategies of the "non-grain" production were proposed, in terms of region and category. 1) One strategy was to differentiate between the planting structure "non-food" and agricultural industry structure "non-grain". There was a small impact of planting structure "non-grain" on the production capacity of cultivated land. By contrast, the large impact was found to be strictly prohibited in the agricultural industry structure "non-grain" on the production capacity of cultivated land. 2) High mountain areas were strengthen by the supervision of agro-industrial structure "non-grain", whereas, the low hill areas were for the planting structure "non-grain". 3) The "non-grain" production of agricultural industry structure can be curbed to increase the construction of farmland infrastructure in the high mountainous and hilly areas, particularly for the better farming conditions. 4) Much attention should be paid to those land types that converted from growing food crops to others. The potential cultivated land resources should be remediated in the stages to restore the cultivated land.