基于SWAT模型的关中盆地地下水对气候变化的响应研究

发布时间：2018-05-25 09:16

本文选题：关中盆地 + 气候变化　；参考：《长安大学》2015年硕士论文

【摘要】：水是生命之源,是人类生存和发展必不可少的资源,而我国人均淡水资源量远远低于世界的平均水平,近些年来在全球气候变暖和人类活动影响下,水资源量急剧减少,河流流量减少甚至断流、水环境开始恶化,直接威胁着人类的生存和发展。关中盆地是资源性缺水地区,气温、降水、蒸发、径流、地下水位等水循环要素受气候变化的影响发生了明显的改变,水资源供需矛盾更加突出,水资源安全形势更为严峻,因此研究关中盆地地下水对气候变化的响应显得尤为迫切和重要。本论文以地下水对气候变化的响应为主线,研究了关中盆地近六十年的气温和降水量的变化特征,运用MK趋势分析和MK突变检验分别对年平均气温、季平均气温、年降水量、季降水量序列进行了分析,并用小波分析分析了年平均气温和年降水量的周期性变化;根据将近三十年的地下水位长期观测资料,分析了关中盆地地下水位空间分布和动态变化特征;利用DEM数字高程数据、土地利用类型数据、土壤属性数据、降水和气温资料,建立了SWAT水文分布模型,设定气候变化情景模式,计算出气候变化情景下地下水的变化。最后得出如下结论:1.关中盆地年降水量从1960年左右开始有减少的趋势,但减少的趋势不显著,1995年以后,年降水量才呈现显著的减少趋势。关中盆地不同地区年降水量的突变时间不同,武功、西安和华山的突变时间分别为1961年、1966年和1986年。关中盆地年降水量存在3年、5年,20年、35年左右的周期,其中20年和35年左右的周期最为显著。关中盆地秋季和春季近几年降水量减少趋势明显,冬季和夏季变化不明显。2.关中盆地年平均气温从1990年左右开始呈现上升趋势,到2000年后这种上升趋势开始更加显著。宝鸡、西安和华山三个地区的年平均气温突变时间均在1995年左右,而武功的突变点在1990年。关中盆地年平均气温存在15年、30年左右的周期,其中30年左右的周期最为显著。关中盆地冬季和秋季气温从1995年开始显著升高,春季气温从2003年开始有显著的增加趋势,而夏季气温变化不明显。3.关中盆地地下水水位分布与地形等高线基本一致,地下水流由盆地两侧向盆地中心偏东方向运动。关中盆地地下水水位在上世纪八十年代基本随着降水量变化处于波动阶段,进入九十年代,地下水出现缓慢的下降趋势,到1995年,地下水位开始急剧的下降,直到2000年,地下水位下降趋势才有所缓解,部分地区水位还出现回升。4.利用数字高程数据,土地利用数据、土壤数据、气象数据等,建立关中盆地整个流域的SWAT水文模型。由模型计算地下水补给量随着降水量的增加而增加,当气温不变,降水量减少10%时,地下水补给量减少29.83%,降水量增加10%时,地下水补给量增加34.52%。当降水量不变时,温度增加对地下水补给量影响很小,温度增加一摄氏度时,地下水补给量减少1.1%。5.耦合SWAT模型和MODFLOW模型,计算气候变化情景模式下地下水位的变化。当降水量增加或减少10%时,地下水位也相应的增加或减少0.6~1.5m,不同的地区水位变化幅度有所差异。气温变化对地下水位影响很小。
[Abstract]:Water is the source of life and essential resources for the survival and development of human beings. The amount of freshwater resources per capita in China is far below the average level of the world. In recent years, under the influence of global warming and human activities, the amount of water resources has been reduced sharply, the flow of rivers is reduced or even disconnected, and the water environment has begun to deteriorate, which directly threatens the survival and survival of human beings. Development. Guanzhong Basin is a resource deficient area. The water circulation factors such as temperature, precipitation, evaporation, runoff and groundwater level have been greatly affected by the influence of climate change. The contradiction between supply and demand of water resources is more prominent and the situation of water resources safety is more severe. Therefore, it is particularly urgent to study the response of groundwater to climate change in Guanzhong Basin. This paper, taking the response of groundwater to climate change as the main line, studied the change characteristics of temperature and precipitation in Guanzhong Basin for nearly sixty years. The MK trend analysis and MK mutation test were used to analyze the annual mean temperature, seasonal average temperature, annual precipitation and seasonal drop water, and the annual mean temperature was analyzed with wavelet analysis. According to the long-term observation data of the groundwater level for nearly thirty years, the spatial distribution and dynamic change characteristics of the groundwater level in Guanzhong Basin are analyzed, and the SWAT hydrological distribution model is set up by using DEM digital elevation data, land use type data, soil attribute data, precipitation and temperature data, and climate change is set up. Finally, the following conclusions are drawn: the annual precipitation in the 1. Guanzhong Basin has been reduced from around 1960, but the decrease trend is not significant. After 1995, the annual precipitation has a significant reduction trend. The change time of annual precipitation in the different areas of the central basin is different. The mutation time of Xi'an and Huashan in Xi'an and Huashan is 1961, 1966 and 1986 respectively. The annual precipitation in Guanzhong Basin is 3 years, 5 years, 20 years, and 35 years, of which the period of 20 and 35 years is the most obvious. The average temperature began to rise from around 1990, and the rising trend began to become more significant after 2000. The average annual temperature mutation time in three regions of Baoji, Xi'an and Huashan were around 1995, and the abrupt point of Wu Gong was in 1990. The annual average temperature in Guanzhong Basin was 15 years, 30 years or so, of which about 30 years. The winter and autumn temperature in Guanzhong Basin began to rise significantly from 1995, and the temperature in spring began to increase significantly in the spring from 2003, but the change of the temperature of the summer temperature was not obvious in the.3. Guanzhong Basin. The groundwater level distribution was basically consistent with the topographic contour line, and the groundwater flow was moved from both sides of the basin to the east of the basin center. In the 80s last century, the water level of the basin was basically in the fluctuating stage with the change of precipitation. In 90s, the groundwater decreased slowly. By 1995, the groundwater level began to decline sharply. Until 2000, the downward trend of the groundwater level was slowly solved, and the water level in some areas was also rising.4. using the high number of figures. The SWAT hydrological model of the whole valley of Guanzhong Basin is established by the process data, land use data, soil data, meteorological data and so on. The model calculation of groundwater recharge increases with the increase of precipitation. When the temperature is fixed, the precipitation is reduced by 10%, the groundwater recharge is reduced by 29.83% and the precipitation is increased by 10%, the groundwater recharge is increased by 34.52%. When the amount of precipitation is constant, the effect of temperature increase on the supply of groundwater is very small. When the temperature increases one degree centigrade, the groundwater recharge reduces the 1.1%.5. coupling SWAT model and the MODFLOW model, and calculates the change of the groundwater level under the climate change scenario model. When the precipitation increases or decreases by 10%, the groundwater level is also increased or reduced by 0.6~1.5m, The variation of water level varies in different regions. The change of temperature has little effect on the groundwater level.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P641;P467

【参考文献】