基于土壤水分动态平衡方程的天津冬小麦干旱变化特征分析

Drought Change of the Winter Wheat in Tianjin Revealed by Soil Water Homeostasis

利用天津宝坻区1959～2009年气象资料,应用土壤水分动态平衡方程,对无灌溉条件下1m深土层非胁迫水分累积亏缺量进行计算,根据干旱指标,分析该地区干旱变化特征。结果表明,在自然条件下,该地区冬小麦生长季97%年份出现不同程度的干旱,春旱极易发生。

Based on the meteorological data in Baodi District of Tianjin during 1959-2009,cumulated non-stress water deficit of the top one meter soil layer under no irrigation conditions was calculated by using soil water dynamic equilibrium equation.The drought change characteristics of this area were analyzed according to drought index.The results indicated that the occurrence reached 97% for drought at different levels in natural situation in growth season of winter wheat.Additionally,it was found that the occurrence of drought was the highest in spring.