极端干旱区咸水灌溉下流沙压埋的减蒸抑盐效应  

Effect of shifting sand burial on evaporation reduction and salt restraint under saline water irrigation in extremely arid region

作　　者：张建国[1,2] 赵英[1] 徐新文[2] 雷加强[2] 李生宇[2] 王永东[2] 

机构地区：[1]西北农林科技大学资源环境学院,农业部西北植物营养与农业环境重点实验室,陕西杨凌712100 [2]中国科学院新疆生态与地理研究所,乌鲁木齐830011

出　　处：《应用生态学报》2014年第5期1415-1421,共7页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(40901137,41030530,41271341);中国科学院干旱区生物地理与生物资源重点实验室开放课题基金项目(LBBS-2010-009);西北农林科技大学博士科研启动项目(Z109021003)资助

摘　　要：塔克拉玛干沙漠公路防护林采用2.58～29.70g·L^-1高矿化度地下水滴灌，流沙压埋和水盐胁迫均是其面临的主要问题.探讨流沙压埋对土壤水分蒸发、盐分表聚及其分布的影响，对节水抑盐和指导干旱沙区水土资源的合理利用具有重要意义.采用微型蒸发器（MLS）研究了不同厚度沙埋下土壤蒸发及其水盐动态，并采用田间控制试验研究了滴管带不同厚度流沙压埋下土壤水盐分布状况.结果表明：1～5cm沙埋下，MLS土壤日蒸发量和累积蒸发量均随沙埋厚度的增加而逐渐降低，累积蒸发量比对照降低2.5％～13.7％，土壤水分蒸发抑制效率随着沙埋厚度的增加而增高，1～5cm厚度的沙埋蒸发抑制效率达16.7％～79.0％，流沙压埋界面以下土壤最终含水量随沙埋厚度的增加而增大，比对照增加2.5％～13.7％.随着沙埋厚度的增加，MLS内流沙表层电导率逐渐降低，分别降低1.19～6.00mS·cm^-1，而压埋界面以下土壤盐分含量逐渐增加，且流沙表层盐分的变幅大于压埋界面以下土层.成水滴灌条件下，流沙压埋界面以下土壤含水量随着压埋厚度的增加而增大，分别增加0.4％～2.0％；流沙表层积盐量随着流沙压埋厚度的增加呈先增后减的趋势，流沙压埋厚度为10cm时最高，电导率达7.77mS·cm^-1，流沙压埋界面以下土层含盐量均远低于流沙浅层，35cm可作为节水抑盐的临界流沙压埋厚度.流沙压埋对土壤水分蒸发和盐分表聚抑制作用极为明显，在干旱沙漠区，可以利用流沙压埋这一自然灾害，达到减蒸抑盐、变害为利的目的.The Taklimakan Desert Highway Shelterbelt is drip-irrigated with high saline groundwater （2.58-29.70 g · L^-1） , and shifting sand burial and watersalt stress are most common and serious problems in this region. So it is of great importance to study the effect of shifting sand burial on soil moisture evaporation, salt accumulation and their distribution for water saving, salinity restraint, and suitable utilization of local land and water resources. In this study, Micro-Lysimeters （MLS） were used to investigate dynamics of soil moisture and salt under different thicknesses of sand burial （1,2, 3, 4, and 5 cm） , and field control experiments of drip-irrigation were also carried out to investigate soil moisture and salt distribution under different thicknesses of shifting sand burial （5, 10, 15, 20, 25, 30, 35, and 40 cm）. The soil daily and cumulative evaporation decreased with the increase of sand burial thickness in MLS, cumulative evaporation decreased by 2.5%-13.7% compared with control. And evaporative inhibiting efficiency increased with sand burial thickness, evaporative inhibiting efficiency of 1-5 cm sand burial was 16.7% -79.0%. Final soil moisturecontent beneath the interface of sand burial increased with sand burial thickness, and it increased by 2.5% -13.7% than control. The topsoil EC of shifting sand in MLS decreased by 1.19-6.00 mS · cm^-1 with the increasing sand burial thickness, whereas soil salt content beneath the interface in MLS increased and amplitude of the topsoil salt content was higher than that of the subsoil. Under drip-irrigation with saline groundwater, average soil moisture beneath the interface of shifting sand burial increased by 0.4% -2.0% compare with control, and the highest value of EC was 7.77 mS · cm-1 when the sand burial thickness was 10 cm. The trend of salt accumulation content at shifting sand surface increased firstly, and then decreased with the increasing sand burial thickness. Soil salt contents beneath the interface of shifting sand burial were

关 键 词：流沙压埋 蒸发 盐分表聚 水盐分布 咸水滴灌 塔克拉玛干沙漠 

分 类 号：S156[农业科学—土壤学]