基于SIMPEL模型的土壤墒情预测研究

摘要

The forecast of soil moisture lays foundation for water management in farmlands.The change of soil moisture is influenced by multiple meteorological factors.It becomes much significant for improvement of agricultural production and effective use of water to explore the rule of water dynamic at small scale,spatially or temporally.In the research,water dynamic in soil horizons at 0-40 cm in winter wheat belts was simulated by SIMPLE model as per water balance principle.Furthermore,ETp in fields was computed according to Haude method (DVWK standards); retained amount of water in fields and wilting coefficient were calculated based on soil parameters with SPAW (Soil-Plant-Air-Water).The simulated results of SIMPLE model showed that the correlation of measured and simulated water content in soils was 0.95 and relative error averaged lower than 3.1％,suggesting that the model would make a more precise estimation of water content in root zone in the area.%土壤墒情预报是农业生产中农田水分管理的前提和基础.土壤墒情的变化受多种气象因素的影响,为了提高农业产量,有效利用水分,在更小的时间和空间尺度上掌握土壤水分的动态变化规律显得尤为重要.该研究以德国奥斯纳布吕克地区田间试验资料为基础,使用德国SIMPEL模型按照水分平衡原理分层模拟了试验区冬小麦0～40 cm土层的土壤水分含量变化情况.农田潜在蒸散量的计算采用德国DVWK标准方法Haude计算方法.土壤的田间持水量和凋萎系数采用德国常用的水文模型SPAW(Soil-Plant-Air-Water)按照土壤参数分层计算.SIMPEL模型模拟结果显示,土壤体积含水量实测数据与模拟数据的相关性在0.95,平均相对误差低于3.1％,说明模型能够相对准确的预测此地区根层的土壤水分含量.