塔里木沙漠公路防护林生态工程全长436 km,位于极端干旱的塔克拉玛干沙漠,造林树种以抗逆性较强的沙拐枣属(Calligonum L.)、柽柳属(Tamarix L.)、梭梭属(Haloxylon Bunge)等优良防风固沙灌木为主,防护林植物的蒸腾耗水和灌溉管理是防护林可持续的核心问题。为探求适合塔里木沙漠公路防护林的节水技术,利用微型蒸渗仪研究了塔克拉玛干沙漠腹地咸水灌溉条件下Guilspare(浓度1.5%v/v)施用量对土壤蒸发和水盐垂直分布的影响。结果表明:(1)Guils-pare对土壤蒸发有显著影响,其施用量与累积蒸发量间呈对数关系。当施用量小于4.0 L/m2时,土壤日蒸发量在试验初期均表现为对照组(CK)大于处理组,试验中后期却相反;当施用量大于4.0 L/m2时,日蒸发量始终小于CK。(2)Guilspare施用量为6.0 L/m2的抑制效率最大,与其他处理(除7.0 L/m2)间差异达到显著水平(p﹤0.05)。(3)施用Guilspare对土壤蒸发第一阶段的蒸发强度有明显的减弱作用,其减弱程度与施用量的大小有密切关系,当施用量为6.0 L/m2时,蒸发强度最弱。(4)相同初始含水量条件下,表层土壤含水量和土壤浸提液电导率(除7.0 L/m2)均随着施用量的增大而变小;其他土层(除10~14 cm),两者均随着施用量的增大而变大。
The Tarim Desert Highway shelterbelt,436 kilometers long,locates in the hinterland of such an extreme arid environment in the Taklimakan Desert.Its main afforested species are Tamarix L.,Calligonum arborescens,and Haloxylon ammodendron,which are good windbreak and sand-fixation trees with strong salt and drought resistance.The strong soil evaporation and capillarity make soil salts from irrigation move upwards with soil water and accumulate on soil surface gradually,even form salt crusts,and then soil evaporation and irrigation management become focuses of the shelterbelt sustainable development.In order to explore suitable water-saving techniques for the Tarim Desert Highway shelterbelt,a simulative experiment with Micro-lysimeter(MLS) was conducted to research the effect of Guilspare under saline water irrigation on soil evaporation and vertical distribution of soil water and salts in the hinterland of Taklimakan Desert.In the study,a solution of 1.5 % v/v of the hydrophobic polymer Guilspare was sprayed to the aeolian soil surface at applied quantity of 0.5,1.0,2.0,3.0,4.0,5.0,6.0 and 7.0 L/m2,to text the inhibition on soil evaporation and effect on soil water and soil salt movement.The results show as follows:(1)Guilspare inhibits soil evaporation significantly and a logarithmic relationship was observed between its applied quantity and the accumulative soil evaporation,and at the quantity 4.0 L/m2 the daily evaporation of the blank(CK) was higher than that of other treatments in the early days while lower in the later days,and at the quantity 4.0 L/m2 the daily evaporation of CK was always more than the treatments;(2)the inhabitation of the treatment 6.0 l/m2 was maximum and differed from other treatments(7.0 L/m2 except) significantly at P 0.05,and in addition,the maximum inhibition was not arrived in early days but on the 10th day after the irrigation beginning;(3)Guilspare weakened the evaporation intensity at first phase obviously,the weakened degree had close relati