微咸水灌溉下砂层级配及覆砂厚度对土壤水盐运移的影响  

The Effects of Grading and Thickness of Gravel Mulching on Water and Salt Movement in Soil under Brackish Water Irrigation

作　　者：谭军利[1,2] 王西娜[3] 金慧娟 杜飞飞 田军仓[1,2] TAN Junli;WANG Xina;JIN Huijuan;DU Feifei;TIAN Juncang(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China;Engineering Research Center of the Ministry of Education for Modern Agricultural Water Resources High Efficiency in Arid Area,Yinchuan 750021,China;School of Agriculture,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学土木与水利工程学院,银川750021 [2]旱区现代农业水资源高效利用教育部工程研究中心,银川750021 [3]宁夏大学农学院,银川750021

出　　处：《灌溉排水学报》2020年第9期7-13,共7页Journal of Irrigation and Drainage

基　　金：宁夏高等学校一流学科建设(水利工程)资助项目(NXYLXK2017A03);国家自然科学基金项目(51309135,31860590)。

摘　　要：【目的】探究砂层级配及厚度对微咸水灌溉条件下土壤水盐运移过程的影响机理。【方法】通过土柱模拟试验,研究了微咸水灌溉条件下砂层粗、中及细级配及覆砂厚度为0、5、10、15 cm对土壤水分和盐分运移规律及动态分布的影响。【结果】相同覆砂厚度条件下,砂层级配对土壤水盐分布的影响较小,但中级配(砂层加权直径为5.0 cm)保水效果小于粗级配(砂层加权直径为6.0 cm)及细级配(砂层加权直径为4.5 cm)处理;与不覆砂相比,无论覆砂厚度大或小均能大幅度保蓄土壤水分,抑制土壤盐分表聚;在灌水量相同条件下,覆砂厚度超过10 cm会影响入渗水分的再分布过程。【结论】砂层级配对土壤水盐分布的影响不如砂层厚度大,覆砂即使5 cm也能保蓄较多的水分,抑制表层盐分累积。【Objectives】Gravel mulching is a technique commonly used in arid and semi-arid regions to reduce water evaporation from soil,and the grading and thickness of the gravel layer are two factors affecting soil moisture dynamics.The purpose of this paper is to investigate experimentally how irrigation with brackish water affects water and salt movement in soil mulched with gravel of different thicknesses and grading.【Method】The experiment was conducted in soil columns with their tops covered by a gravel layer with its grading ranging from coarse to fine sand,and thicknesses ranging from 0(CK)to 15 cm.The experiment lasted one month,during which we measured soil water and salt distributions in the soil columns.【Result】The impact of gravel grading on moisture and salt distributions in the soil was insignificant,although the medium grading was less effective than the coarse and fine gradings in conserving soil water.The results also showed that gravel mulching increased soil moisture and reduced salt accumulation in the proximity of the soil surface,compared to not mulching,especially when the mulch was more than 10 cm thick.【Conclusion】The effect of gravel grading on moisture and salt distribution in the soil was less than that of mulch thickness,and the gravel mulch could keep soil more moist and suppress salt accumulation in the proximity of the soil surface even when the mulch was 5 cm thick.

关 键 词：压砂地 微咸水 覆砂厚度 砂层级配 水盐分布 

分 类 号：S152.7[农业科学—土壤学] S287[农业科学—农业基础科学]