新疆塔里木河下游生态输水对胡杨叶片MDA含量的影响

EFFECT OF ECOLOGICAL WATER INPUT ON MDA OF POPULUS EUPHRATICA OLIV LEAF IN THE LOWER REACHES OF THE TARIM RIVER*

结合塔里木河下游生态输水后地下水位变化的监测和胡杨叶片中能够指示环境变化的丙二醛 (MDA)含量的测定 ,对塔里木河下游地下水位变化与胡杨叶片中MDA积累变化关系进行了分析 .结果表明 ,胡杨叶片MDA含量随着地下水位的下降、干旱胁迫程度的增强呈现出明显增加态势 ,与地下水位变化存在密切关系 .结合野外样地调查分析得出 :地下水位埋深在 4 .4 2m时 ,胡杨生长已受到水分胁迫 ;在 5 .78～ 6 .4 6m之间 ,胡杨受到中度水分胁迫 ,胡杨的生长发育将受到明显的抑制 ;而在 8.89～ 9.74m之间 ,胡杨受到重度水分胁迫 ,将面临着死亡的威胁 .图 6参

Based on the analysis of groundwater level in the lower reaches of the Tarim River and the test of Populus euphratica leaves's malondialdehyde (MDA) content, the main natural vegetation in the area, the relationship between the groundwater level and the accumulation of P. euphratica's MDA were studied. The result showed that the MDA content in P. euphratica obviously increased with decreasing of groundwater level. The degree of water stress for P. euphratica was closely related to the changes in groundwater level. According to the field investigation and analysis of vegetation, P. euphratica underwent water stress while the groundwater level was 4.42 m deep; P. euphratica had moderate water stress while that is between 5.78～ 6.46 m deep and the growth of P. euphratica was restrained obviously; P. euphratica had critical water stress while that was between 8.89～9.74 m deep and most of the trees withered in the lower reaches of the Tarim River. Fig 6, Ref 22