摘要
岩溶地下水位对降雨响应具有时空变异性,甑皮岩遗址地下水动力系统结构的认识存在分歧。利用高分辨率降雨水位数据,将研究区分割为不同含水体,通过水位动态、相关分析、滑动窗口采样相关分析等方法,探讨岩溶地下水对降雨响应时空变异特征及成因。结果表明,岩溶强发育、扩散流导水的含水体水位对降雨的响应表现为缓升缓降,水位自相关性强;发育岩溶管道的含水体水位表现为陡升陡降,水位自相关系数衰减速率快,对降雨响应的滞后时间短,互相关函数图呈多峰型;岩溶发育的极不均匀性是造成空间响应差异的主要原因。雨季地下水位对降雨响应的滞后时间远小于枯季;雨季累积降雨量大、水位埋深浅、包气带长期处于饱和或者近饱和状态,降雨垂直入渗补给历时短;雨季暴雨频繁导致含水体地下水短期内形成较大水力梯度,径流补给速度加快。综合分析认为,甑皮岩遗址地下水动力系统由NE向岩溶管道、NS向管道-裂隙以及NE向强径流带3个子径流系统组成。
The response of karst groundwater level to rainfall features spatial and temporal variability. There is no consensus regarding the groundwater dynamic system structure of the Zengpiyan cave site in Guilin,Guangxi,China.Based on high-resolution data on rainfall water level,the study area was divided into different aquifers. The characteristics and cause of spatial and temporal variability of karst groundwater level’s response to rainfall were explored using water level dynamics,correlation analysis,and sliding window cross-correlation analysis. The results show that in terms of the response to rainfall,the water level of aquifers with a high degree of karst development and diffusion flow for water diversion rises and falls slowly,featuring a strong autocorrelation in water level;the water level of aquifers developed with karst conduits rises and falls rapidly,with a fast decay rate of water-level autocorrelation coefficient,a short lag time in response to rainfall,and a multimodal cross-correlation function graph. The extreme non-uniformity of karst development is the primary cause of differences in spatial response. The response lag of the groundwater level to rainfall in the rainy season is much smaller than during the dry season. This is because,in the rainy season,there is a large amount of cumulative rainfall,the buried depth of groundwater is shallow,and the aerated zone is constantly in a saturated or near-saturated state,causing the groundwater supply to become saturated by vertical rainfall infiltration relatively quickly. Further,the frequent rainstorms in the rainy season can generate to a large hydraulic gradient in a short period of time,accelerating the runoff replenishment speed of aquifers. Taken together,the groundwater system of the Zengpiyan cave site consists of 3 sub-runoff systems,i. e. the NE karst conduit,the NS conduit-fracture,and the NE strong runoff zones. The research results can provide theoretical basis and technical reference for the cave site to formulate plans of preventing and controlling underground water hazards.
作者
王朋辉
姜光辉
袁道先
汤庆佳
张强
WANG Penghui;JIANG Guanghui;YUAN Daoxian;TANG Qingjia;ZHANG Qiang(Key Laboratory of Karst Dynamics,MNR&GZAR,Institute of Karst Geology,CAGS,Guilin 541004,China;School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China)
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2019年第1期56-64,共9页
Advances in Water Science
基金
国家自然科学基金资助项目(41172231
41472239)~~
关键词
岩溶
地下水位
降雨响应
序列相关
时空变异
karst
piezometric level
rainfall response
serial correlation correlation
spatio-temporal variability
