黄土高原塬区麦田土壤水分变化特征及其对降水的响应  

The Variations of Soil Water of Wheat Field and Its Relation to Precipitation in Loess Plateau Mesa Region

作　　者：梁芸[1,2] 张峰 王小巍[1] 赵建华[2] 

机构地区：[1]西北区域气候中心,甘肃兰州730020 [2]中国气象局兰州干旱气象研究所,甘肃兰州730020 [3]庆阳市气象局,甘肃西峰745000

出　　处：《土壤通报》2012年第1期20-24,共5页Chinese Journal of Soil Science

基　　金：甘肃省自然科学研究基金计划(096RJZA130)资助

摘　　要：利用对黄土高原塬区具有较好代表性的西峰站近18 a（1989~2006年）降水和土壤水分资料,研究麦田土壤水分的变化特征及其与不同尺度的标准化降水指数SPI的关系。结果表明：（1）4~6月份,是麦田深层土壤水分的失墒期,6月前后土壤干旱最严重;（2）7~10月是麦田深层土壤的增墒期,土壤水分与降水的显著相关深度逐渐向深层推移,10月底墒得到有效补充;（3）失墒期深层土壤水分对表层水分的滞后时间小于增墒期的,分别为1个月左右和2个月左右;（4）一个月尺度的降水对耕作层的影响是最大的,2~6个月尺度降水的影响深度主要在30~150 cm,大于6个月尺度的SPI影响深度在主要70~200 cm;（5）除了作物蒸腾影响,降水尺度越大,土壤水分受影响的深度越大。The variations of soil water in wheat field and its Indices （SPI） were established based on the recent 18-year relations to different-scalar Standardized Precipitation （1989 - 2006） data of precipitation and soil water in Xifeng station which is the best representative of Losses Plateau Mesa Region. The results showed that： （1） The water loss stage of deep soil layer was in Apr-Jun and the sever drought stage of soil was in the vicinity of Jun, （2） The water gain stage of deep soil layer was from Jul to Oct when the depth with significant correlation between soil water and precipitation increased gradually with time and pre-sowing soil water was adequately supplied by the end of Oct; （3） The time lags responsible for the response of deep-layer soil water to surface soil water in water loss stage and gain stage were one month and two months, respectively, the former obviously bigger than the latter; （4） One-month-scalar precipitation affectd mostly the plough horizon while two-six-month-scalar precipitations affected mostly in 30 - 150 cm, and the precipitations with month scalar greater than six months mostly in 70 - 200 cm; （5） Except the effectiveness of crop＇s transpiration, the bigger the month precipitation was, the deeper the soil water was affected.

关 键 词：黄土高原 土壤水分 SPI 

分 类 号：S152.7[农业科学—土壤学]