陕西、陇东农田土壤水分动态模拟预测研究

A STUDY OF THE DYNAMIC SIMULATION AND FORECASTING OF FARMLAND SOIL WATER IN SHANXI AND EASTERN GANSU

本文针对半干旱、半湿润易旱地区农田土壤水分运动特点,由水分扩散方程和土壤热扩散方程推导出农田土壤水分动态模拟模型。经冬麦田间实测资料检验后,利用常规气象和农业气象资料,对陕西、陇东半干旱及半湿润易旱区不同土壤带的代表性站点进行农田土壤水分动态模拟。然后修正边界条件,建立农田土壤水分预测模型,并输入田间实测资料进行土壤水分预测。结果表明了在半干旱,半湿润易旱地区研究土壤水分运动规律时考虑土壤温度及其梯度影响的必要性,以及利用台站常规资料进行多点模拟预测的可行性。

By using the soil water and heat diffusion equation,a farmland soil water dy-narnic simulation model is presented for the semiarid, semi-humid and prone-to-drought areas. Testified by observed data in the winter wheat fields, the medel is usedto simulate the farmland soil water dynamic changes using the routine meteorologicaland agrometeorological data from the representative stations in different soil zones of thesaid areas in Shaanxi province and the eastern part of Gansu province. After modifyingthe boundary conditions,the forecasting model is developed and used to predict farmlandsoil water by means of the observed data. Results suggest that it is necessary to considerthe effects of soil temperature and its gradient. The feasibility of simulating farmlandwater using routine meteorological and agrometeorological data is also discussed.