太湖流域粮食生产对耕地利用变化动态响应分析及预测

认识耕地利用与粮食生产的耦合作用规律是确保粮食安全和可持续发展的基础。基于模型模拟、GIS和多目标情景模拟等方法,在定量分析粮食生产对耕地利用变化动态响应基础上,分析流域粮食生产变化的关键驱动要素及粮食增产潜力,为流域耕地利用动态调控和粮食安全问题解决提供参考。结果表明:(1)1985～2015年流域耕地利用与粮食生产变化空间集聚性显著,耕地量变、耕地利用结构和方式变化幅度分别为39.2%、23.6%和19.3%,上述变化导致粮食减产44.1%;(2)1985～2015年耕地量变对流域粮食减产贡献率为50.7%,耕地利用方式变化和耕地量变则分别以43.4%和76.3%的贡献率成为前后15年粮食减产的主要驱动因素。集聚在流域北部56.8%的区域受耕地量变影响显著;太湖东南24.3%的区域和杭州-桐乡-嘉善一线等18.9%的区域分别受耕地利用方式和结构变化影响较大。随时间变化,耕地量变影响加剧,粮食减幅增加;(3)未来耕地数量持续减少,粮食安全压力较大,低-中-高方案变动下耕地量变影响范围缩小53.5%,耕地利用方式和结构影响区分别增加了2倍和1.25倍,粮食增产区由5.4%增加到54.1%。不同区域粮食生产对耕地利用变化响应的时空差异显著,未来响应变化敏感区将是流域粮食增产潜力区和耕地利用关键调控区。

Analysis and Forecast on Dynamic Response of Grain Production to Cropland Use Changes in Taihu Lake Basin

Understanding the coupling law between cropland use and grain production is the basis for food security and sustainable development. Based on model simulation, GIS, multi-objective scenario simulation and quantitative analysis on the response of grain production to cropland use changes,this study explored the key driving factors of grain production changes and potential of grain production.The study can provide a reference for decision-making on the dynamic control of cropland use and food security in Taihu Lake Basin.The results are as follows:(1) Spatial aggregation of cropland use and grain production changes was significant.The changing rate of cropland quantity and quality(CQQ) , cropland structure,and cropland pattern were 39.2%,23.6% and 19.3% respectively from 1985 to 2015. Affected by cropland changes, changing rate of grain production was 44.1%.(2)The contribution of CQQ changes to decline in grain production was 50.7% from 1985 to 2015,and the contribution of cropland structure and CQQ changes to decline in grain production were 43.4% and 76.3 % respectively in the first 15 years and next 15 years. The CQQ changes were the main factor that affected grain production in counties accounting for 56.8% which located in the north of Taihu Lake Basin. Cropland structure change were the main factor that affected grain production in counties accounting for 24.3% which located in the southeast of Taihu Lake Basin, and counties accounting for 18.9% which were along Hangzhou-Tongxiang-Jiashan were mainly effected by cropland structure changes.With the evolution of time, the decline in grain production and influence degree of CQQ changes on grain production increased significantly. (3)Cropland decrease and food security pressure will continue in the future.With the changes of scenarios from trend growth to cropland protection, the counties whose grain production are mainly effected by CQQ changes reduce by 53.5%, the counties whose grain production are mainly effected by cropland structure and cropland pattern increase by two times and 1.25 times respectively,and regions with grain increase grow from 5.4% to 54.1%.It is concluded that the response patterns are different in different region and the sensitive counties of grain production change to scenario changes will become the main potential area of grain recovery and cropland adjustment in the future.