Identification of Potential Distribution Areas of Rice Planting Cultural Landscape in the Han River Basin

Objective Under the background of the rural revitalization strategy, it is very important to explore and protect agricultural landscapes. Agricultural landscape is a "Continuous landscape" in cultural landscape, with the evolutionary characteristics of mutual adaptation between farming activities and natural geographical environment. The rice planting cultural landscape is an agricultural landscape that is rooted in rice planting agricultural production activities and demonstrates a harmonious symbiotic relationship with nature. This study identifies potential distribution areas of rice planting cultural landscapes from the perspective of bio-cultural integration. This approach incorporates considerations on the impact of farming cultural activities on the environment, and aims to provide a reference for the hierarchical and classified management of agricultural landscape. Methods This study screened identification factors based on the Outstanding Universal Value Evaluation Criteria for Agricultural Landscapes. Based on the biological and cultural characteristics of the listed important rice planting agricultural heritages in China, a method for identifying the potential distribution areas of rice cultural landscapes was constructed at the county level from the perspectives of geographical environment (biological factors) and historical culture (cultural factors). The geographical environment identification factors are climate, topography, soil and hydrology, and the maximum entropy model is used for simulation; the historical and cultural identification factors are farming history, farming culture, traditional villages and historical water conservancy facilities, and ArcGIS is used for overlay analysis. Results Most areas of the Han River Basin have terrain and climate conditions suitable for rice growth, and have abundant water resources suitable for paddy field irrigation. In addition, the Han River Basin has rich historical and cultural value of rice farming, and Neolithic rice planting relics have been discovered. As a major north-south transportation route, the frequent population migration activities in the Han River Basin promoted agricultural exchanges between the north and the south and promoted the spread of rice culture. The identification results show that there are potential distribution areas of rice planting cultural landscape geographical environment in the upper, middle and lower reaches of the basin. Soil type, bio12 (annual precipitation), bio14 (precipitation in the driest month) and elevation are the main environmental factors affecting the distribution of rice-growing agricultural cultural heritage. In terms of history and culture, the overall scores of the upper and lower reaches of the Han River are relatively high, and the district with the highest score is Chenggu County in Hanzhong City. The high potential area of rice planting cultural landscape is an area with high scores in both geographical environment and historical culture, distributed in Hanbin District, Shiquan County, Hanyin County of Ankang City in the upper reaches of the basin and Jingshan, Zhongxiang, Tianmen and Qianjiang in the lower reaches. Among them, Hanyin County and Jingshan City are the counties where the important rice planting cultural landscapes in China are located. The general potential area is an area with a geographical environment score greater than 0.75 but a relatively low historical and cultural score, including Xixiang County of Hanzhong City, Laohekou City, Zaoyang City, Yicheng City, Xiangzhou District, Baokang County of Xiangyang City and Dongbao District of Jingmen City. The remaining districts and counties are non-potential areas. In order to clarify the biocultural characteristics of high-potential areas, the study extracted the scores of each factor and divided the high-potential rice-growing agricultural landscape in the Han River Basin into mountainous, plain-hilly, and plain rice planting cultural landscape types by combining topographic and geomorphic characteristics. Different landscape types formed the cultural landscape patterns of "mountain-forest-village-farmlands ", "valley-slope-farmlands -village", and "lake-embankment- farmlands -village". Conclusion The formation of rice planting cultural landscape is inseparable from the interaction between biology and culture. In order to avoid the destruction of valuable rice planting cultural landscape by construction activities, this study preliminarily constructed a method for identifying the potential distribution area of rice planting cultural landscape under the integration of biology and culture, providing an action reference for the excavation, protection and utilization of agricultural landscape. However, due to the long-time span and large scope of the research, as well as limited historical research materials, historical information data still needs to be further supplemented and improved; in addition, the interaction between historical culture and the natural environment still needs to be further explored in future research.