【作者】 张奎俊；

【导师】 李宗礼； 李仁年；

【作者基本信息】 兰州理工大学 ， 水利水电工程， 2008， 硕士

【摘要】 石羊河流域水资源短缺,下游民勤绿洲湖泊萎缩、干涸,天然植被枯萎、死亡,土地沙漠化、盐渍化进程加快,地下水位下降,矿化度上升,生态退化严重,危及区域的生态系统的安全,保护和恢复重建势在必行,研究民勤绿洲生态需水问题意义重大。首先,通过对国内外生态环境需水研究的现状分析,提出民勤绿洲的生态需水的概念,阐述生态环境需水的分类及分析方法。其次,分析了20世纪60年代到2001年的石羊河下游民勤绿洲土地利用格局的演化趋势,表明流域下游荒漠化程度远远大于绿洲化程度,必须尽快提供生态用水以抢救民勤绿洲,分析计算了不同情景的生态需水量。(1)基于一定生态保护与恢复目标,结合民勤绿洲的实际情况,选择适合民勤绿洲的生态需水的计算方法。本文分别运用傅抱璞法、彭曼公式法、阿维里扬诺夫潜水蒸发模型计算分析民勤绿洲生态需水量,并对此三种方法的结果进行耦合分析,得出现状民勤绿洲生态需水量为1.856×10~8m~3,到2020年民勤绿洲生态环境需水量达到2.716×10~8m~3。(2)对地下水生态环境需水量和补给来源等一系列问题进行了研究,提出了恢复地下水生态需水量的计算方法。通过对地下水水位埋深与地表植被、潜水年蒸发强度、表土积盐量三种关系进行耦合,确定合理地下水生态水位的上、下限,进而估算恢复民勤绿洲地下水生态需水量为29.32×10~8m~3～35.27×10~8m~3,并在采补平衡的原则上,对民勤绿洲地下水环境恢复措施进行了分析,提出了防止地下水生态系统进一步恶化的对策。最后,对解决民勤绿洲水危机对策及措施进行了探讨。更多还原

【Abstract】 The basin of the Shiyang River is lack of water resource.At the Minqin oasis of the river lower,the lakes are shrinking and dry,the natural vegetation is withered and died,the process of the land desertification and salinization is speeding up,the groundwater level is dropping,the salinity is increasing,and the ecological degradation is serious.These are threatening the ecological system of the regional safety,and the protection and restoration are imperative.So it is most significant to study Minqin oasis ecological water issues.Firstly,through the status analysis of water demand about the ecological environment at home and abroad,the concept of ecological environment water demand on the Minqin oasis is presented.And the classification and method of ecological water demand is classified.Secondly,the land utilization of the lower reaches of the Shiyang River in Minqin Oasis is analyzed in detail from 1960s to 2001.The results show that the degree of desertification is much more severe than that of oasisment.Ecological water must be provided as soon as possible to rescue the Minqin oasis.The analysis and calculation for the different cases of ecological water demand are as follows.(1)Based on certain ecological protection and recovery goals,integrated with the actual situation in Minqin Oasis,the calculation methods of the ecological water requirements are presented which are fit for the Minqin oasis.In this thesis,the methods of FuBao-pu,Pengman formula and Avermectin diving evaporation model are used to analyze the Minqin oasis ecological water demand.Furthermore,coupled analysis is done for the calculation results of the three methods.It shows that the ecological water demand in this area is 1.856×10~8 m~3 at the present,while it will reach 2.716×10~8m~3 by the year 2020.(2)In this paper,ecological groundwater demand and supply are studied,and the computation method for restoring ecological groundwater demand are investigated. Through coupling the groundwater level with the plant in earth surface,the evaporation intensity of groundwater per year and the salt quantity accumulation in surface soil,a reasonable up/down limits is determined for the ecological level of underground water.And then the underground ecological water demand is estimated at 29.32×10~8m~3～35.27×10~8m~3 which is for the Minqin oasis restored.On the principle of balancing between the supply and demand,the measures for restoring the underground water in the Minqin oasis are analyzed,and the plan are conducted to prevent further deterioration of the groundwater ecological system.At the end of this paper,the strategy and measures that are solved the water crisis in the Minqin oasis have also been discussed.更多还原