Spatio-temporal evolution of the early-warning status of cultivated land and its driving factors: A case study of Heilongjiang Province, China

Scientific identification of the early-warning status in relation to cultivated land system security (CLSS) is essential for future food security and sustainable development. It is important to establish the early-warning status of cultivated land as it may signal forthcoming problems and even large-scale environmental catastrophes as an effective means to understand both the current status and future development trends of the CLSS. However, the systematic assessment of the early-warning of status of CLSS has not been previously been conducted at the municipal level, and an in-depth study and discussion of its fundamental driving factors is lacking. Thus, we introduce the biological immunity mechanism by way of analogy and demonstrate the feasibility of its application in the early-warning of CLSS. A novel conceptual early-warning index system is developed and this framework applied to 12 cities in Heilongjiang Province of northeast China using adopting fourteen possible indicators. The spatiotemporal evolution of the early-warning status had been explored over the period 1995-2014 using rescaled range (R/S) analysis. Furthermore, the fundamental factors of the early-warning were explored by establishing a rational panel data model. The results indicate that 1) CLSS early-warning status initially rose and then decreased over the last 20 years. 2) The severe level warning areas are mainly found in the southeast and west of the region, while the secure and relatively secure areas are mainly concentrated in the middle-north and southern areas. 3) The observed patterns indicate that, with the exception of Yichun and Suihua, the early-warning status of the province will develop in the future along the same lines as it did so historically. 4) The results of regression analysis indicate that rational panel data model construction should be verified so as not to produce pseudo-regression and that four main driving factors (natural population growth rate, agricultural waste load per unit area of cultivated land, natural disasters index, and industrial wastewater load per unit area of cultivated land) are significantly positively correlated with the early-warning status; one factor (forest cover) is negatively correlated. Policy-makers need to consider the key factors affecting the early warning status of cultivated land and its spatiotemporal evolution in different regions to formulate appropriate measures in order to mitigate against future threats.