Impacts of thickening unsaturated zone on groundwater recharge in the North China Plain

Cao, Guoliang1,2; Scanlon, Bridget R.3; Han, Dongmei4; Zheng, Chunmiao5,6

2016-06

10.1016/j.jhydrol.2016.03.049

JOURNAL OF HYDROLOGY   影响因子和分区

0022-1694

1879-2707

Unsustainable groundwater development shown by rapid groundwater depletion in the North China Plain (NCP) underscores the need to quantify spatiotemporal variability in groundwater recharge for improved management of the resource. The objective of this study was to assess spatiotemporal variability in recharge in response to thickening of the unsaturated zone in the NCP. Recharge was estimated by linking a soil water balance (SWB) model, on the basis of monthly meteorological data, irrigation applications, and soil moisture monitoring data (1993-2008), to the water table using a deep unsaturated zone flow model. The dynamic bottom boundary (water table) position was provided by the saturated zone flow component, which simulates regional pumping. The model results clearly indicate the effects of unsaturated zone thickening on both temporal distribution and magnitude of recharge: smoothing temporal variability in recharge, and increasing unsaturated storage and lag time between percolation and recharge. The thickening unsaturated zone can result in average recharge reduction of up to similar to 70% in loam soils with water table declines >= 30 m. Declining groundwater levels with irrigation sourced by groundwater converts percolation to unsaturated zone storage, averaging 14 mm equivalent water depth per year in mostly loam soil over the study period, accounting for similar to 30% of the saturated groundwater storage depletion. This study demonstrates that, in thickening unsaturated zones, modeling approaches that directly equate deep drainage with recharge will overestimate the amount and underestimate the time lag between percolation and recharge, emphasizing the importance of more realistic simulation of the continuity of unsaturated and saturated storage to provide more reliable estimates of spatiotemporal variability in recharge. (C) 2016 Elsevier B.V. All rights reserved.

Groundwater recharge Soil water balance Unsaturated flow North China Plain

SCI ; EI

英语

其他

National Natural Science Foundation of China[41401012] ; National Natural Science Foundation of China[41371057]

Engineering ; Geology ; Water Resources

Engineering, Civil ; Geosciences, Multidisciplinary ; Water Resources

WOS:000376212200025

ELSEVIER SCIENCE BV

20161502211352

Atmospheric movements ; Digital storage ; Groundwater resources ; Irrigation ; Meteorology ; Moisture control ; Soil moisture ; Solvents ; Water conservation

Atmospheric Properties:443.1 ; Water Resources:444 ; Groundwater:444.2 ; Soils and Soil Mechanics:483.1 ; Data Storage, Equipment and Techniques:722.1 ; Specific Variables Control:731.3 ; Chemical Agents and Basic Industrial Chemicals:803 ; Agricultural Methods:821.3

ENGINEERING

Web of Science

1.China Inst Water Resources & Hydropower Res, State Key Lab Simulat & Regulat Water Cycle River, Beijing 100038, Peoples R China
2.Natl Ctr Groundwater Res & Training, Adelaide, SA, Australia
3.Univ Texas Austin, Bur Econ Geol, Jackson Sch Geosci, Austin, TX 78758 USA
4.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Water Cycle & Related Land Surface Proc, Beijing 100101, Peoples R China
5.South Univ Sci & Technol China, Sch Environm Sci & Engn, Shenzhen 518055, Peoples R China
6.Univ Alabama, Dept Geol Sci, Tuscaloosa, AL USA

Cao, Guoliang,Scanlon, Bridget R.,Han, Dongmei,et al. Impacts of thickening unsaturated zone on groundwater recharge in the North China Plain[J]. JOURNAL OF HYDROLOGY,2016,537:260-270.

Cao, Guoliang,Scanlon, Bridget R.,Han, Dongmei,&Zheng, Chunmiao.(2016).Impacts of thickening unsaturated zone on groundwater recharge in the North China Plain.JOURNAL OF HYDROLOGY,537,260-270.

Cao, Guoliang,et al."Impacts of thickening unsaturated zone on groundwater recharge in the North China Plain".JOURNAL OF HYDROLOGY 537(2016):260-270.