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从 YIELD模型的来源、输入文件及基本参数、模型中作物生产力计算各个子模型以及计算流程 4个方面作了简单的叙述 ,以黄土丘陵沟壑区典型小流域晋西狼窝沟为例 ,在地理信息系统 ( GIS)技术支持下 ,应用 YIELD模型对该流域的作物生产潜力进行了模拟 ,并从作物类型、地类、耕作措施及气候条件 4个方面对影响该流域作物产量的因素进行分析。结果表明 ,该模型对不同作物的模拟产量在总体上与实测产量基本相符合 ,表明模型可以应用于黄土丘陵沟壑区的作物产量模拟之中 ;对于不同地类来说 ,坝地的土壤水分和肥力条件明显高于梯田和坡耕地 ,因而坝地的模拟产量也高于梯田和坡地 ,但三者之间的差距没有实测产量显著 ;耕作措施是提高作物生产力的有效途径 ,对地膜覆盖、梯田以及施肥等耕作措施的模拟产量表明 ,这 3种耕作措施均能有效的提高作物生产力 ,其产量提高率均平均在 85 %以上 ,其中以施肥对作物的增产作用最大 ,增产率高达 95 % ,这与实测产量资料基本一致 ;气候条件是影响作物生产的直接因素 ,模拟结果表明模型对降水量和温度等气候条件十分敏感 ,不同年份降水量和温度的差异将直接导致作物生产力的显著不同。对 YIELD模型的模拟结果分析表明 ,该模型可以有效地应用于黄土丘陵沟壑区的作物生产潜力研究
From the source of YIELD model, input files and basic parameters, calculation of crop productivity in the model and four aspects of the calculation process are briefly described. Taking wolves ditch in Jinxi, a typical small watershed in the Loess Plateau, as an example, YIELD model was used to simulate the potential of crop production in this drainage basin under the support of Information System (GIS) technology. The factors influencing the crop yield in this catchment were analyzed from four aspects: crop type, landform, tillage measures and climatic conditions. The results show that the simulated yield of different crops in this model is basically consistent with the measured yield, indicating that the model can be applied to crop yield simulation in the hilly and gully regions of the Loess Plateau. For different types of land, the soil moisture and Fertility conditions were significantly higher than that of terraced fields and sloping fields. Therefore, the simulation yield of dams was also higher than that of terraced fields and slopes. However, there was no significant difference between the three measures. Tillage measures were an effective way to improve crop productivity. And the simulation yield of fertilization and other tillage measures showed that all three tillage measures could effectively increase the productivity of the crop with the average rate of increase of above 85%, of which fertilization exerted the most effect on crop yield increase rate up to 95% The results show that the model is sensitive to the climatic conditions such as precipitation and temperature. The difference between precipitation and temperature in different years will directly lead to significant differences in crop productivity. The simulation results of YIELD model show that the model can be effectively applied to crop production potentiality in loess hilly and gully regions