Due to long-term over-exploitation of groundwater in Beijing Municipality, regional groundwater funnels have formed and land subsidence has been induced. By combining a groundwater monitoring network, GPS monitor- ing...Due to long-term over-exploitation of groundwater in Beijing Municipality, regional groundwater funnels have formed and land subsidence has been induced. By combining a groundwater monitoring network, GPS monitor- ing network data, radar satellite SAR data, GIS and other new technologies, a coupled process model based on the dy- namic variation of groundwater and the deformation response of land subsidence has been established. The dynamic variation of groundwater fimnels and the land subsidence response process were analyzed systematically in Beijing. Study results indicate that current groundwater funnel areas are distributed mainly in the southwest of Shunyi District, the northeast of Chaoyang District and the northwest of Tongzhou District, with an average decline rate of groundwa- ter level of 2.66 rn/yr and a maximum of 3.82 m/yr in the center of the funnels. Seasonal and interannual differences exist in the response model of land subsidence to groundwater funnels with uneven spatial and temporal distribution, where the maximum land subsidence rate was about --41.08 mm/yr and the area with a subsidence rate greater than 30 mm/yr was about 1637.29 km2. Although a consistency was revealed to exist between a groundwater funnel and the spatial distribution characteristics of the corresponding land subsidence funnel, this consistency was not perfect. The results showed that the response model of land subsidence to the dynamic variation of groundwater was more revealing when combining conventional technologies with InSAR, GIS, GPS, providing a new strategy for environmental and hydrogeological research and a scientific basis for regional land subsidence control.展开更多
地面沉降是由于地表高程降低所诱发的区域环境地质灾害.城市快速发展带来的载荷的增加影响地面沉降的发展.选取覆盖北京平原区的TM遥感影像,以北京典型地下水漏斗区为研究区,在NDBI、MNDWI、SAVI指数基础上,计算遥感建筑用地指数(IBI),...地面沉降是由于地表高程降低所诱发的区域环境地质灾害.城市快速发展带来的载荷的增加影响地面沉降的发展.选取覆盖北京平原区的TM遥感影像,以北京典型地下水漏斗区为研究区,在NDBI、MNDWI、SAVI指数基础上,计算遥感建筑用地指数(IBI),获取建筑用地(载荷)时空密度差异信息;结合永久散射体干涉测量(Persistent Scatterers for SAR Interferometry,PS-InSAR)监测结果,基于GIS空间分析技术和统计分析方法,从3种不同的空间采样角度,分析载荷密度差异与地面沉降的相关性.结论显示,(1)地面沉降的不均匀性与载荷密度的正相关性表现为:沉降速率值越大,Spearman秩相关系数越大;(2)动静载荷的共同作用相对于单纯的静载荷对地面沉降的影响更明显;(3)在较短时间周期内,相对于地下水开采,载荷对地面沉降的影响较小,但仍旧是不容忽视的问题,需要长期系统性的研究.展开更多
基金Under the auspices of Program of International S&T Cooperation (No. 2010DFA92400)Non-profit Industry Financial Program of the Ministry of Water Resources (No. 200901091)+2 种基金Beijing Municipal Natural Science Foundation (No. 8101002)Beijing Municipal Education Commission Plans to Focus Science and Technology Projects (No. KZ201010028030)National Natural Science Foundation of China (No. 41130744,41171335)
文摘Due to long-term over-exploitation of groundwater in Beijing Municipality, regional groundwater funnels have formed and land subsidence has been induced. By combining a groundwater monitoring network, GPS monitor- ing network data, radar satellite SAR data, GIS and other new technologies, a coupled process model based on the dy- namic variation of groundwater and the deformation response of land subsidence has been established. The dynamic variation of groundwater fimnels and the land subsidence response process were analyzed systematically in Beijing. Study results indicate that current groundwater funnel areas are distributed mainly in the southwest of Shunyi District, the northeast of Chaoyang District and the northwest of Tongzhou District, with an average decline rate of groundwa- ter level of 2.66 rn/yr and a maximum of 3.82 m/yr in the center of the funnels. Seasonal and interannual differences exist in the response model of land subsidence to groundwater funnels with uneven spatial and temporal distribution, where the maximum land subsidence rate was about --41.08 mm/yr and the area with a subsidence rate greater than 30 mm/yr was about 1637.29 km2. Although a consistency was revealed to exist between a groundwater funnel and the spatial distribution characteristics of the corresponding land subsidence funnel, this consistency was not perfect. The results showed that the response model of land subsidence to the dynamic variation of groundwater was more revealing when combining conventional technologies with InSAR, GIS, GPS, providing a new strategy for environmental and hydrogeological research and a scientific basis for regional land subsidence control.
文摘地面沉降是由于地表高程降低所诱发的区域环境地质灾害.城市快速发展带来的载荷的增加影响地面沉降的发展.选取覆盖北京平原区的TM遥感影像,以北京典型地下水漏斗区为研究区,在NDBI、MNDWI、SAVI指数基础上,计算遥感建筑用地指数(IBI),获取建筑用地(载荷)时空密度差异信息;结合永久散射体干涉测量(Persistent Scatterers for SAR Interferometry,PS-InSAR)监测结果,基于GIS空间分析技术和统计分析方法,从3种不同的空间采样角度,分析载荷密度差异与地面沉降的相关性.结论显示,(1)地面沉降的不均匀性与载荷密度的正相关性表现为:沉降速率值越大,Spearman秩相关系数越大;(2)动静载荷的共同作用相对于单纯的静载荷对地面沉降的影响更明显;(3)在较短时间周期内,相对于地下水开采,载荷对地面沉降的影响较小,但仍旧是不容忽视的问题,需要长期系统性的研究.
