塔里木河下游胡杨径向生长量对生态输水的响应

Response of Radial Increment of Populus euphratica to Ecological Water Conveyance in Lower Reaches of the Tarim River

以塔里木河下游的胡杨径向生长量为研究对象,借鉴树木年轮水文学的方法,采用单因素方差分析方法,从数理统计学的角度分析了胡杨径向生长量对生态输水的响应过程。结果表明:①距离河道300m范围内,生态输水前后及输水期间各年份之间,胡杨的径向生长量在0.001的水平上差异极显著,胡杨对生态输水的响应非常积极;②距离河道300m范围外,胡杨的径向生长量在0.05的水平上差异不显著,胡杨对生态输水的响应不积极;③线性的生态输水只是缓解了河道附近植被的衰退,改善了局部生态环境,却无法从根本上缓解整个塔里木河下游生态环境的恶化,塔里木河下游的生态环境呈现出局部改善、整体恶化的趋势。

The Tarim River Basin,located in Xinjiang Uygur Autonomous Region in northwest China,is the largest inland river basin in China.The ecological process here has undergone great changes due to human disturbance over the past 50 years.In order to rescue the strategic ＂green corridor＂ in lower reaches of the Tarim River,ecological water conveyance has been bring into effect from May 14th,2000.By using dendrohydtology for reference and taking single factor analysis of variance,the authors researched how Populus euphratica＇s growth rings responded to the ecological water conveyance.The results showed that within the distance of 300 m to the river,the radial increment of Populus euphratica is highly different at significant level 0.001;on the contrary,beyond 300 m to the river,the difference of radial increment of Populus euphratica isn＇t significant at level 0.05.That means Populus euphratica within 300 m range to the river would respond more positively to the water conveyance than those beyond 300 m.By this token,although the linear conveyance can alleviate vegetation decline near watercourses,and partly improve the entironment,it is unable to hold back the whole deteriorated ecosystem along the Tarim River.