土壤水氮迁移转化与作物生长耦合模拟

Coupled simulation on soil-water-nitrogen transport and transformation and crop growth

定量描述农田土壤-作物系统中水氮迁移转化规律,对水氮资源高效利用和水土环境保护具有重要的意义。以土壤水、热和溶质迁移转化动力过程为基础,综合考虑气象因素变化和土壤水氮动态变化及其对作物生长的影响,构建了土壤水、热、氮迁移转化与作物生长耦合模拟模型。并应用该模型对2007-2008年冬小麦生育期内的土壤水分、氮素转化运移以及冬小麦产量、生物量、腾发量(ET)进行模拟,模拟结果与实测数据均吻合良好。可应用该模型模拟不同作物种类、不同灌水施肥条件下土壤水分与氮素动态变化过程和作物生长状况,进而获得农田水肥优化管理模式。

Quantitative description of the soil-water-nitrogen transport and transformation in soil-crop system is very important to the high efficient use of water and nitrogen resources and protection of water and soil environment.A coupling model was developed to simulate the soil-water-nitrogen transport and transformation and crop growth based on the dynamic processes of soil water,heat and solute transport and transformation,and with considering the variation of meteorological factors and the dynamics of soil water and nitrogen and their impact on crop growth.The data sets of 2007-2008 field experiments for winter wheat with different irrigation depth were used to validate the soil-water-nitrogen transport and transformation with crop growth simulation model.The results indicated that the simulated values of soil water content,soil nitrate concentration,grain yield,biomass and evapotranspiration were in good agreement with the observed values.The model can be used to simulate the dynamics of soil water and nitrogen change pattern and crop growing pattern for different crop species under different water and nitrogen management practices,and thus the optimal water and fertilizer management pattern for farmland can be obtained.