基于地形梯度的重庆市近40年水田及旱地时空演变特征.

[Objective] Exploring the distribution and change characteristics of paddy fields and dry land is the basis for clarifying the law of regional cultivated land changes, and providing data support and decision-making basis for the implementation of cultivated land protection. [Method] Using geospatial information technology and the interpretation results of land use types from the 1980, 2000 and 2018 LandsatTM images of Chongqing City, the transfer characteristics of the paddy field and dry land in the region were analyzed, and the two types of cultivated land were compared at different altitudes, slopes, and slopes. The distribution and transformation of the slope upward. [Results] The distribution and transformation of paddy fields and dry land showed complexity and difference in different topographical spaces. Paddy fields are mainly distributed in areas with a slope of less than 15° and an altitude of less than 600 m; while dry land is more evenly distributed at various altitudes and has a wider suitability for slopes. The characteristics of mutual transfer between paddy field and dry land and various land types are quite different under different altitude, slope, and aspect conditions. During 1980-2000 and 2000-2018, paddy fields and dry land were mainly transferred out, and the lost paddy fields were mainly converted into construction land; affected by factors such as urban construction occupation, conversion of farmland to forests and grasslands, dry land and other land types Switching between is more frequent. Affected by multiple factors, the dominant farming areas of paddy fields gradually migrated from low-altitude gentle slope areas to middle-low-altitude and medium-slope areas, while the main farming dominant areas of dryland mainly shifted to middle-altitude and moderate-slope areas. [Conclusion] Topographical conditions restrict agricultural production activities, and it is necessary to focus on strengthening the management of cultivated land loss in low-altitude and relatively flat areas. [ABSTRACT FROM AUTHOR]