荒漠河岸林地区胡杨幼苗根系水力提升作用探究  

Research on Hydraulic Lifting of Populus euphratica Seedling Roots in Desert Riparian Forest Area

作　　者：苏芮[1,2] 李卫红[1] 郝兴明[1] 郭斌[1,2] 朱成刚[1,2] 

机构地区：[1]中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室,新疆乌鲁木齐830011 [2]中国科学院研究生院,北京100049

出　　处：《干旱区研究》2012年第2期342-346,共5页Arid Zone Research

基　　金：中国科学院重要方向项目(KZCX2-YW-Q10-3-3);中国科学院"西部之光"项目(RCPY200903);国家自然科学基金(40871059)共同资助

摘　　要：植物水力提升作用是指低蒸腾条件下处于湿润区域根系吸水后运输到干燥区,并将水分释放到根际周围的干土中的现象。通过上下层分根试验法,研究生长季胡杨幼苗的根系提水作用。结果表明:①与成年胡杨相似,胡杨幼苗根系存在水力提升作用;②幼苗的水力提升作用发生在21:00时至次日6:00时,生长季3株胡杨幼苗的总提水量分别为2.78 kg,2.31 kg和2.46 kg,日均提水量为0.022 6 kg,0.018 7 kg和0.02 0 kg;③3株胡杨幼苗的日均提水量占上层土壤蒸发量的13%～20%,在植物蒸腾作用明显的7～8月,日均提水量也较大;④下层土壤的根系生物量和提水量相关性显著。Plant hydraulic lifting is a phenomenon that the roots in deep wet soil uptake water from subsoil and carry water though the transport tissues to the roots in topsoil and into dry topsoil around them when transpiration is lower at night.The method in which the roots were separated into those in topsoil and subsoil was used to study the hydraulic lifting of Populus euphratica seedling roots in their whole growing season.The results are as follows;（1） There is a hydraulic lifting function in roots of P.euphratica seedlings;（2） Hydraulic lifting occurred from 21：00 to 6：00 am next morning.The total uptake water volumes of the seedling roots of 3 P.euphratica plants in growing season were 2.78,2.31 and 2.46 kg,and their average daily volumes were 0.022 6,0.018 7 and 0.020 kg,respectively;（3） The proportion of hydraulic lifting water volume of P.euphratica seedling roots varied in a range of 13%-20% of evaporation from topsoil.During the period from June to August when transpiration was significant,the average daily hydraulic lifting water volume was also high;（4） There was a significant correlation between root biomass and hydraulic lifting water volume in subsoil.

关 键 词：胡杨幼苗 根系 水力提升 蒸腾 荒漠河岸林 塔里木河 

分 类 号：S792.119[农业科学—林木遗传育种]