咸水灌溉沙地后的水盐运移规律  

THE MOVEMENT OF WATER AND SALT IN SANDY LAND AFTER IRRIGATED WITH SALINE WATER

作　　者：黄强[1] 李生秀[2] 宋郁东[1] 

机构地区：[1]中国科学院新疆生态与地理研究所,乌鲁木齐830011 [2]西北农林科技大学,陕西杨凌712100

出　　处：《土壤学报》2003年第4期547-553,共7页Acta Pedologica Sinica

基　　金：中国西部干旱区生态环境演变与调控研究 (G19990 43 5 0 6);中国科学院西部之光项目资助

摘　　要：实地观测不同深度土壤含水率、基质势、土壤溶液含盐率 ,利用定位通量法和盐分均衡法 ,研究了咸水小畦灌条件下塔克拉玛干沙漠土壤的水盐运移规律。结果表明 :(1)在小畦灌条件下 ,停止灌水后 2 4h ,91.2 5 %的灌水渗入 15 0cm土层以下 ;停止灌水后 72h ,96.6%的灌水渗入 15 0cm土层以下 ,此时 ,0～ 15 0cm土层土壤平均含水率为 0 .0 5 3cm3cm- 3,此后土壤含水率缓慢下降。 (2 )秋季停灌后 ,土壤表面蒸发量在 2～ 6mm。停灌后 2h ,上行水区域在 0～ 2 0cm土层 ;停灌后 60h ,上行水区域在 0～ 90cm ;此后至停灌后 14 4h ,上行水深度稳定在地下 90cm。 (3 )咸水灌溉后 ,80cm以上土层土壤溶液含盐率明显下降 ,以下土壤溶液含盐率变化不明显。停灌 2 4h后 ,0～ 15 0cm土层液相盐分储量开始降低 ,至停灌后 14 4h ,0～ 15 0cm土层液相储盐量相当于灌水前的 5 3 .46%。 (4 )停止灌水后 ,10 0cm× 10 0cm地面日平均积盐量在 13～ 3 5g。A field experiment for studying water and salt movement in soil after basin irri gated by saline ground water was conducted in the center of Takelamakan Desert. A series of data about soil water potential, soil water content and EC value of soil solution at different depths along the soil profile were obtained at diffe rent times after stopping irrigation. By analyzing these data using method of wa ter and salt balance, some results of water and salt movement in soil were obtai ned as follows: (1) After stopping irrigation 24 hours, 8.85% of the amount of i rrigation water would be contained in the soil layer of 0～150 cm. After stoppin g irrigation 72 h, 3.4% of the amount of irrigation water would be contained in l ayer of 0～150 cm, and average soil water content in this soil layer was 5.3%. A f ter this time, soil water content in this layer reduced slowly. (2) During the t ime from stopping irrigation to seventh day after stopping irrigation in autumn, the daily evaporation water amount was between 2～6 mm. 2 hours after stopping i rrigation, soil water contained in the layer of 0～20 cm moved upward to the sur f ace of ground, while 72～144 hours after stopping irrigation, the upward region o f soil water extended to the depth of 90 cm underground. (3) When irrigated by s aline water with EC value of 6.3 mS cm -1 , The EC value of soil solution re duced obviously in upper part of the layer and was almost same as that of before irrig ation in lower part of the layer. 24 h after stopping irrigation, the amount of salt contained in solution of layer of 0～150 cm was less than that of before ir r igation, while 144 h after stopping irrigation, it was only 53.46% of that of be fore irrigation. (4) After stopping irrigation, the daily amount of salt accumul ated on ground surface with area of 100 cm×100 cm would be 13～35 g in autumn.

关 键 词：咸水灌溉 沙地 水盐运移规律 土壤 含水率 基质 土壤溶液 含盐率 定位通量法 

分 类 号：S152[农业科学—土壤学]