西安地区地下水动态及地下水供水安全研究

发布时间：2018-02-22 11:07

本文关键词： 水位埋深动态类型预测供水安全地下水源地　出处：《长安大学》2014年硕士论文　论文类型：学位论文

【摘要】：西安是我国西北地区最大的城市，20世纪70～90年代由于城市快速发展，长期超量开采地下水，使得地下水位急剧下降，造成了一系列的环境地质问题，严重影响了城市的健康发展。因此，本文通过收集西安地区的自然地理、社会经济、水文气象、水文地质条件、地下水开发利用情况和地下水位监测数据等资料，，分析了研究区1984～2010年地下水位埋深的时空变化规律，划分了地下水动态类型，研究了气候变化和人类活动对地下水位的影响，预测了2011～2020年地下水位埋深的变化趋势，并在实地调研的基础上对各水源地地下水供水安全程度进行了分析评价，主要得到以下几点结论： 1、分析地下水位埋深得出，1984～2010年研究区潜水水位平均埋深为11.72m，最大降差可达5.92m，主要经历了快速下降期—稳定期—缓慢回升期3个阶段；承压水头在1997年以前呈明显下降趋势，普遍下降50m左右，最大下降量可达100m，1997年以后城区自备井开采区呈明显回升趋势，最大回升量可达3.3m/a。 2、对不同区域潜水水位埋深变化时间序列的趋势检验得出，西郊沣皂河水源地（K83-3付）和城区自备井（291）开采区潜水水位埋深变化趋势分别在2006和2003年出现了非常明显的突变，潜水水位埋深均有下降转变为回升趋势；北郊渭滨水源地潜水水位埋深在1996年发生突变，1997～2010年期间水位埋深呈显著下降趋势；其它地区潜水水位变化趋势没有发生突变情况，但农灌开采区和灞河水源地的潜水水位埋深对环境变化的敏感性较强，其水位埋深波动性明显大于一、二级阶地地区。 3、采用克里格（Kriging）插值法对地下水埋深进行分区，得其埋深空间分布情况基本表现为东南大、北部小，开采区潜水水位和承压水头埋深明显大于其它地区。同时，结合MapGis属性库统计功能，重点研究了1998～2010年潜水水位和承压水头不同埋深分区的面积变化情况，得潜水水位埋深主要集中到10～20m范围，该分区占总面积的比例已由45.9%增长至56.8%；承压水头埋深大于100m的区域逐渐减小，20～60m和60～100m的区域面积有所增长，埋深主要集中到20～60m，该区约占总面积的50%左右。 4、运用主成分投影-聚类分析法，将西安地区不同水文地质单元及开采区的潜水水位动态类型划分为水文强、中、弱和开采影响型四类，并结合水文气象因素与水位埋深的相关分析和主成分分析结果，得出非开采区范围内从河漫滩至二级阶地潜水水位受水文因素影响由强变弱，水文气象因素的影响程度由大到小排列为径流量＞降水量＞蒸发量＞气温等其它因素，开采区内潜水动态受地下水开采影响较大。 5、通过回归模型，研究了工业活动与潜水水位埋深的关系，得出上世纪90年代工业活动对潜水水位的影响最为明显，每增加10亿元的工业产值，就能使平均潜水水位下降0.2m左右。 6、建立了降水量、蒸发量和地下水开采量为影响因素的潜水水位埋深自适应模糊推理系统（ANFIS）神经网络预测模型，并运用该模型与灰色模型（GM（1，1））和径向基（RBF）神经网络相结合，预测出2011～2020年西安地区潜水水位平均埋深变化情况，结果表明其平均水位埋深在12.5m左右波动，整体有微弱的回升趋势。 7、通过实地调研，分析了研究区地下水供水存在的问题，并参考其它地区的相关研究成果构建了供水安全评价指标体系，利用层次-集对分析法对5个地下水源地的供水安全状况进行分析评价，结果表明其供水安全程度的优劣排序为：皂河地下水源地＞渭河西北郊地下水源地＞渭滨地下水源地＞沣河地下水源地＞灞河地下水源地。
[Abstract]:Xi'an is the largest city in Northwest China, in twentieth Century 70~90 years due to the rapid development of the city, long-term over exploitation of groundwater, the groundwater level decreased sharply, causing a series of environmental and geological problems, has seriously affected the healthy development of the city. Therefore, this paper through the collection of physical geography, the social economy in Xi'an area, hydrological and Meteorological. Hydrogeological conditions and groundwater monitoring data of groundwater exploitation and utilization, analyzes the temporal and spatial variation of 1984~2010 years of groundwater depth, groundwater dynamic type division, study the effects of climate change and human activities on groundwater level and predict the variation trend of underground water depth of 2011~2020 years, analysis evaluation of the groundwater and the water supply safety degree on the basis of the investigation, the main draw the following conclusions:
1, the depth of analysis show that the groundwater level, 1984~2010 years of the study area groundwater level average depth is 11.72m, the biggest drop of up to 5.92m, which experienced a rapid decline in 3 stages - stable stage - slow recovery period; pressure head was significantly decreased in 1997 before the general decline of about 50m, the maximum reduction of up to 100m after 1997, the city wells mining area showed a recovery trend, the maximum recovery capacity of up to 3.3m/a.
2, the trend test of phreatic water level in different regions of the buried depth of time series that the West Feng soap water (K83-3 Fu) and City wells (291) mining area water depth change trend occurred in 2006 and 2003 respectively. The mutation is very obvious, the water depth decreased into an upward trend Beijiao; Weibin water to the water depth is mutated in 1996, during the 1997~2010 years the water depth decreased significantly; the change trend of groundwater level in other regions without mutation, but the sensitivity of agricultural irrigation water in the mining area and Bahe phreatic water level changes on the environment of deep buried strong, the depth of water level fluctuation greater than one, the two terrace area.
3, by Craig (Kriging) interpolation method to groundwater depth partition, the depth distribution of the basic performance of the southeast, north of small mining area water depth and the confined water head was significantly greater than that in other areas. At the same time, combined with the MapGis attribute database statistics, focusing on the changes in the area 1998~2010 years of diving the water level and pressure head in different depth zones, so the water depth is mainly concentrated to the range of 10 ~ 20m, the area accounted for the proportion of the total area has increased from 45.9% to 56.8%; the pressure head depth greater than the 100m of the region was gradually reduced, 20 ~ 60m and 60 ~ 100m area increased, the depth of mainly to 20 ~ 60m, the area accounted for about 50% of the total area.
4, using the principal component projection clustering analysis method, the groundwater level dynamic classification of different hydrogeologic units in Xi'an area and mining area for the hydrological, strong, weak and effect of the extraction of four types, the results of analysis of correlation and principal component combined with the hydrological and meteorological factors and water depth, the non mining area from floodplain to two terraces of phreatic water level affected by hydrological factors from strong to weak, the influence degree of hydrological and meteorological factors from large to small, arranged for other factors of runoff, precipitation, evaporation, temperature, mining area groundwater dynamic influence by diving mining.
5, through regression model, we studied the relationship between industrial activity and groundwater depth. It is concluded that industrial activity has the most obvious impact on groundwater level in the 90s of last century, and that the average diving water level will decrease by 0.2m or so if the industrial output value increases by 1 billion yuan.
6, the establishment of precipitation, evaporation and groundwater exploitation for the adaptive fuzzy inference system for deep water impact factors (ANFIS) neural network prediction model, and uses this model and grey model (GM (1,1)) and radial basis function (RBF) neural network combined to predict water diving in Xi'an area 2011~2020 the average annual change of buried depth, the results show that the average depth of water level fluctuation is about 12.5m, the overall trend has picked up weak.
7, through field research, analyzes the existing problems of groundwater supply, and according to the relevant research results in other areas to build water supply safety evaluation index system, using AHP to analyze and evaluate the safety of water supply in condition of 5 underground water source analysis, the results show that the order of the degree of safety for water supply soap: River groundwater source, northwest Weihe underground water source, Weibin underground water source, Feng River groundwater source, Bahe River groundwater.

【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU991.112

【参考文献】