Evolution of Land Use Suitability and Adaptation Strategies of the Agro-Pastoral Transitional Zone in northern China under Multiple Climate Change Scenarios

The Agro-Pastoral Transitional Zone in northern China is the tail area of the East Asian summer monsoon, as well as the edge area of crop production. It is also a typical ecologically fragile area, and its agricultural and animal husbandry production conditions and ecological status are highly susceptible to climate change. Climate change has uncertainty in long-term processes in the future, and how it affects the suitability of agricultural and pastoral production in the Agro-Pastoral Transitional Zone constitutes a scientific issue of common concern in climate change research and regional sustainable development research. This study is divided into two parts: multi scenario simulation of climate change and evaluation of land use suitability for agriculture and animal husbandry. The first part first simulates the uncertainty of future climate change and the different paths of international response to climate change by setting low, moderate, and high emission scenarios, and then simulates the spatial distribution of annual precipitation and accumulated temperature elements in the Agro-Pastoral Transitional Zone for three years: 2030 (short-term), 2050 (medium-term), and 2100 (long-term). The second part further constructs an evaluation index system for the suitability of agricultural and animal husbandry land use based on the results of multi scenario simulations of climate change, and comprehensively analyzes the quantity structure and spatial distribution of suitability levels for agriculture and animal husbandry in different years under various scenarios. This study has found that in terms of future climate change, the low and moderate emission scenarios of the Agro-Pastoral Transitional Zone in northern China have similar trends in annual precipitation, while the high emission model has more extreme changes in annual precipitation. The spatial distribution of precipitation has always maintained an overall pattern of "more in the east and less in the west". The precipitation changes in the northern and northwestern sections of the Agro-Pastoral Transitional Zone are relatively small, while the dry and wet changes in the northern and southern parts of the northeastern sections are large; The overall distribution of accumulated temperature shows a spatial characteristic of high in the south and low in the north. The accumulated temperature changes in the low emission mode are relatively stable, while the accumulated temperature changes in the moderate and high emission modes are more extreme. The southern part of the northeast section and the eastern part of the north China section are the key areas of alternating cold and warm changes. The suitability analysis of agriculture and animal husbandry under multiple climate scenarios shows that the response to climate change varies in different regions of the Agro-Pastoral Transitional Zone in northern China. Global warming, under moderate and high emission patterns, can help improve the heat conditions in the central and eastern regions of the agro pastoral transition zone in the medium to long term, thereby enhancing the suitability of agriculture and animal husbandry. However, in the western part of the Agro-Pastoral Transitional Zone in northern China, it will further strengthen the constraints of natural conditions, especially in terms of unstable precipitation, and the suitability of land use for agriculture and animal husbandry cannot achieve long-term stable improvement. This study revealed that in the future climate change of the Agro-Pastoral Transitional Zone in northern China, the heat conditions for agricultural and pastoral production will gradually improve under medium to high emission patterns, but there is no significant trend of increase or decrease in precipitation conditions. Under moderate and high emission modes, the suitability of agricultural and pastoral land use in the central and eastern parts of the Agro-Pastoral Transitional Zone in northern China has been improved, indicating that climate warming is beneficial for enhancing the natural suitability of agricultural and pastoral production in the mid to high latitude regions of the Agro-Pastoral Transitional Zone in northern China. This study further discussed the practical path differences and feasibility between moderate and high emission modes, with moderate emission mode being an important mode path for adapting to future climate change in the Agro-Pastoral Transitional Zone.