塔里木河下游生态输水后衰败胡杨林更新能力与条件分析  

Reproductive Ability and Relative Environment Factors of Degraded Populus euphratica Forest in Ecological Water Delivery Project at Lower Reaches of Tarim River

作　　者：赵万羽[1] 陈亚宁[1] 周洪华[1] 周孝明[1] 王小平[2] 

机构地区：[1]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011 [2]新疆塔里木河流域管理局,新疆库尔勒841000

出　　处：《中国沙漠》2009年第1期108-113,共6页Journal of Desert Research

基　　金：中国科学院知识创新西部行动计划项目(KZCX2-XB2-03)资助

摘　　要：对塔里木河下游3个样区生态输水后不同样地0—100 cm深土层中胡杨水平根系分布、繁殖更新能力、地下水位变化及成片胡杨林更新所具备的条件调查分析,结果表明：长期断流后,在低地下水位胁迫下胡杨0—100cm的浅层水平根系发育严重受阻或萎缩消失,萌蘖能力微弱或消失。在距河道边50 m区域内,土层50—100 cm以下有较多的水平根系分布,生态输水后浅层根系具备萌蘖能力;距河道边50～150 m的范围胡杨浅层根系数量减少,分布深度下移,活力降低,实施萌蘖更新有一定的风险,而且随着与断流源区（大西海子水库）距离的增加,风险增大;距河道边250 m以上的区域胡杨水平根系很少,现阶段已基本上失去萌蘖更新的基础条件。胡杨集中分布区地表微地形复杂,大面积地表引流灌溉难度大,使得依靠种子和断根萌蘖实现更新十分困难。Lack of water supply for nearly 30 years has caused seriously degradations of Populus euphratica population in lower reaches of Tarim River. The ability of clonal growth of P. euphratica and their relationship with underground water level, the distribution and activity of lateral root of P. euphratica in 100 cm soil depth were investigated in three sections： Yahepu, Yingsu, Alagan along Tarim River. And the external condition for restoring P. euphratica forestry was also analyzed. It is indicated that the lateral roots within 100 cm soil layer was diminished after long term shortage of water supply. Within a distance of 50 m to the river bank, there are some lateral roots which have the ability for clonal growth. The amount of lateral roots became less, the depth of topside lateral roots move down and the reproductive activity of lateral roots decreased when the distance increased from 50 m to 150 m to the river bank. The risk for clonal growth of P. euphratica increased with the increase from original place of water accumulation. When the distance is more than 250 m to the bank of river, there are nearly no hope to clonal growth because of lack of lateral root. Moreover, the micro landforms near P. euphratica are complicated, which made it difficult to irrigate the tree for further clonal growth.

关 键 词：生态输水 胡杨林更新 塔里木河下游 

分 类 号：Q948.112[生物学—植物学]