Water Relations on Alhagi sparsifolia in the Southern Fringe of Taklamakan Desert  

塔干南缘骆驼刺植被水分关系的研究(英文)

作　　者：李向义[1] 张希明[1] 曾凡江[1] Andrea FOETZKI Frank M .THOMAS 李小明[1] Michael RUNGE 何兴元[3] 

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]德国哥廷根大学生态与生态系统研究所,哥廷根d37073 [3]中国科学院沈阳应用生态研究所,沈阳110016

出　　处：《Acta Botanica Sinica》2002年第10期1219-1224,共6页Acta Botanica Sinica（植物学报：英文版）

基　　金：中国-欧盟合作项目 (ERBIC18CT980275 );国家重点基础研究发展规划项目 (G19990435050 4);中国科学院重大项目(KZ951-B1-231-0 2-0 2 );新疆"山川秀美"计划 (980 10 80 0 1-0 4-0 1);中国科学院创新领域前沿项目 (KZCX-XJLQ-0 5 )。~~

摘　　要：Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive turgor during the summer. The steady high predawn water potential (psi(P)) indicated A. sparsifolia had sufficient hydration and water supply in growing season. In July, water deficit caused by drought stress had no effect on the transpiration of A. sparsifolia. Therefore, drought stress is not a main factor affecting the survival of plants. The physiological adaptation to drought of A. sparsifolia was shown mainly at the leaf level by significant difference (DeltaII) and relative water content (RWC) between the osmotic pressure at full turgor and at turgor loss, by occurring of osmotic adjustment, by high percentage of dry mass-related water content ( WCsat), by RWC at turgor loss point ( RWCp) in stable level and low RWC of the saturated symplast (RWCsym). However, the morphological features of transpiring surface reduction and deep root system seem to be the main way for the plant to adapt to the extreme drought environment. Result also suggests that one time of irregular irrigation in summer will not be helpful to recover water status of A. sparsifolia in location where the water table is very low.对塔克拉玛干沙漠———绿洲过渡带骆驼刺 (AlhagisparsifoliaShap .)水分关系的研究表明 :骆驼刺在夏季保持了正的膨压 ,一直较高较稳定的清晨水势说明植物水分恢复状况良好 ,植物得到了较好的水分供应 ;在 7月 ,干旱胁迫造成的水分亏缺并未影响植株正常的蒸腾作用 ,因而干旱引起的水分胁迫并未威胁到植被的存在。骆驼刺对干旱胁迫的水分生理适应主要体现在叶水平上 ,表现为饱和枝条的渗透势 (Πo)和膨压消失点的渗透势 (Πp)的差值 (ΔΠ)和相对含水量 (RWC)在膨压消失点间更大的变化、渗透调节的产生、较高较稳定的饱和枝条水分与干物质之比 (WCsat)和膨压消失点的相对含水量 (RWCp) ,以及较低的共质体水在总水分中的相对含量 (RWCsym)。但形态学上的特征 ,主要表现为深而发达的根系和蒸腾面积的减少 ,才是骆驼刺适应极端干旱环境的主要途径。非定期的夏季一次性灌溉对地下水位很低地区的骆驼刺植被水分状况的恢复没有帮助。

关 键 词：Alhagi sparsifolia water relation drought stress water potential PV parameters irrigation effect 

分 类 号：Q948[生物学—植物学]