流量与湿润比对湿润体特性影响研究  

Effect of Dripper Discharge and Design Wetted Soil Percentage on Wetted Body and Soil Moisture Distribution

作　　者：王平[1] 胡笑涛[1] 乔林然 李涛龙 郭占娟 张潇潇[1] 

机构地区：[1]西北农林科技大学旱区农业水土工程教育部重点实验室,陕西杨凌712100

出　　处：《中国农村水利水电》2015年第11期11-15,共5页China Rural Water and Hydropower

基　　金：国家自然科学基金项目(51179163)

摘　　要：滴头流量和设计湿润比是滴灌系统设计中的两个重要设计参数,影响土壤湿润范围及作物根系生长。试验采用2种滴头流量和3种设计湿润比,进行了滴灌土壤水分入渗特性试验,观测了湿润锋和土壤含水率变化情况,结果表明:灌水过程中湿润体体积随时间成线性变化,且相关系数R2均大于0.98;灌水结束后,大流量滴头形成的实际湿润比大,平均含水率小,含水率分布更均匀;选取65%和70%田间持水率作为有效含水率下限,大于等于此含水率的湿润体形成的湿润比为有效湿润比,发现灌水结束24h内有效湿润比均为1/2设计湿润比左右,48h较灌水结束24h时有效湿润比有明显的减小;对于作物生长而言,采用有效湿润比代替湿润比,对于指导灌溉系统设计更有参考价值。Dripper discharge and design wetted percentage are two important design parameters, they have impact on the limits of soil moistened and root growth of main crops. This test used two kinds of dripper discharge and three kinds of design wetted percentage, and conducted drip experimental research on soil water infiltration characteristics. Through observing the wetting front and the varia tion of soil water content, the results showed that： the wetted body volume showed a linear variation with time, and the correlation coefficient （R^2） was greater than 0. 98. When the irrigation ended, the greater dripper discharge formed a bigger actual wetted percentage, and the moisture content distributed more uniform; 65% and 70% field capacity was selected as the low limit of effective water content, the wet ratio was formed by wetted body whose moisture content was greater than or equal to this water content is effective wetting ratio, and found that within 24h irrigating ended, the effective wetting ratio were all about 1/2 of design wetting percentage ; for crop growth, effective wetting ratio has a great reference value than design wetted percentage for guiding irrigation of system design.

关 键 词：滴灌 湿润比 滴头流量 有效湿润比 

分 类 号：S275.6[农业科学—农业水土工程]