【作者】 杨鹏年；

【导师】 董新光； 姜卉芳； 李霞；

【作者基本信息】 新疆农业大学 ， 水利水电工程， 2005， 博士

【摘要】 塔里木河位于欧亚大陆腹地,二十世纪五十年代以来,由于上中游进行大规模的农业开发且水利建设的滞后,下游来水量逐年减少。自1972 年后,除个别丰水年外,来水量竟不能使供给塔里木垦区灌溉用水的大西海子水库有余水下泄,致使其下游358 公里的河道断流,大片胡杨林干枯死亡,绿色走廊开始衰败萎缩,生态环境变得极其恶劣,引起了国内外的广泛关注。2000 年4 月以来,适逢开都河天然来水连续偏丰之机,水利部和自治区人民政府做出了向塔里木河下游应急输水的决策,截至2004 年底,共组织了六次输水,累计从大西海子水库下泄生态水17.6 亿m3,台特玛湖形成了一定的水面。本论文依托水利部科技创新项目《塔里木河下游应急输水与生态改善监测评估研究》,分别运用水均衡法和水文法对历次输水后地表水、地下水及土壤水的转化进行分析,结果表明:由于采用逐次推进的输水方式,下泄的水量主要补给予大西海子～阿拉干一带的地下水,河道两侧的地下水与土壤水处于持续恢复之中,地下水的响应宽度已达到距河1km 处。沿河横向:离河越远则矿化度越高,沿河纵向:矿化度从1～3g/L升高至数十克,在区域高矿化水的顶托下,形成了一条低矿化水度的潜水淡化带。利用地下水动力学的理论,建立了间歇输水河道两侧一维地下水非稳定流运动模型,从机理上对浅层地下水的运动加以认识。在此基础上以MODFLOW为工具,现状输水资料为数据源,分别建立了英苏剖面二维流与英苏至阿拉干间的区域三维流地下水模型,其中0～4m和4～6m埋深的面积由输水前的0.8km2和13.4km2上升至五次输水后的42.5km2和91km2;分别对线状和面状输水的效果进行了十年期的预测,表明面状输水的地下水补给量与0～4m和4～6m埋深的面积均大于线状输水,而地下水蒸腾量则小于线状,说明面状输水的效率高于线状输水,可在以后的输水实践中采用。自上世纪六十年代以来塔里木河下游绿色走廊的衰败既有自然原因,又有人类活动的影响,而流域内人类的生产活动是下游生态进行逆向演替的主要作用力。论文以恢复生态学的理论为指导,植被样方调查的结果为依据,分析了塔里木河下游在极端干旱的环境下,输水后植被恢复的自然生态过程,揭示了受损河岸植物群落恢复的过程及环境因子的响应关系。随着应急输水工程的开始,下游生态劣变的趋势得到了初步抑制,以胡杨为代表的荒漠植被开始得到了恢复。数据表明:英苏断面胡杨枝的年平均最大生长量达到了2.24mm,是输水前多年平均量的3.0 倍,在其余断面也有同样的结果。由地下水模型预测的埋深面积,利用上述分布模型推测出了英苏～阿拉干段可以恢复到生长较好状态胡杨的面积为27.8km2;利用相似比拟法,以1957～1959 年卡拉断面的来水量及1958 年统计的胡杨林面积为基础,预测出大西海子水库在年均下泄3.5×108m3水量的情况下,水库以下可恢复的胡杨林面积为209km2。更多还原

【Abstract】 The lower part of the Tarim river located in the inland of the Eurasia continent is atypical arid and desert region. Due to the large scale land reclamation in the upper and middleriver reaches, the runoff of downstream became decreased year after year from 1950s. Thevolume of water was stored in Daxihaizi Reservoir since 1972. As a result, the runoff was cutoff. The populus euphratica forests were lost and the environment became worse and worse.These problems had aroused concern by the government and then the decision of watertransportation was made. The local government transfer water six times and total quantity ofwater achieved 1.76bil cubic meters from 2000 to 2004.This article investigated the movement of surface water, groundwater water and soilwater by use of the ways of water balance and hydrology after water transportations. Theresults indicate that the groundwater was primary replenishment between Daxihanzi andAlagan. The raising width of groundwater achieve 1km by the water transportation. Thedegree of mineralization of groundwater near river had became lower and lower.The feature of response of groundwater table was analyzed. This paper based onBoussinesq Equation and deduced 1D transient groundwater flow of intermittent watertransmitting in the case of souse and sink. The principle of groundwater movement wasunderstood and then the numerical model of 3D-groundwater modeling was established byModflow. The area of depth between 0~4m and 4~6m increased from 0.8km2 and 13.4 km2 to42.5 km2 and 91km2.According to the theory of restoration ecology and the data of vegetation sample, the author analyzedthe process of generative community. Along with the water transportation, the trend of ecology decline hadkept within limits. The research presents that the growth ring of populus euphratica’s branch in Yinsusection was 2.24mm annually after water transportation. It was 3.0 times than 2000. The rulecan be discovered in the whole lower reaches. In the end, the writer forecast that therestoration area of populus euphratica is 209km2 as the runoff is 3.5 bil cubic meters annualy.更多还原