Submarine groundwater discharge revealed by Rn-222: comparison of two continuous on-site Rn-222-in-water measurement methods

Wang, Xuejing1,2; Li, Hailong1,2,3; Zhang, Yan4; Qu, Wenjing5; Schubert, Michael6

2019-08

10.1007/s10040-019-01988-z

HYDROGEOLOGY JOURNAL   影响因子和分区

1431-2174

1435-0157

The natural radioisotope radon (Rn-222) has been widely used as a tracer for quantifying submarine groundwater discharge (SGD). Applicable equipment for continuous radon-in-water detection using a radon-in-air monitor includes the RAD AQUA and the Water Probe (both Durridge Inc., USA). Although both devices have been applied to measure Rn-222 concentrations in coastal water over time periods from hours to days, the monitoring results for the same water body may differ due to the different physical driving forces for Rn-222 degassing from the water, which will result in an inaccurate SGD estimate. Here the two approaches were simultaneously applied for monitoring Rn-222 concentrations at the same site in the same surface-water body (Daya Bay, China). The SGD fluxes resulting from both approaches were evaluated and compared, based on the obtained time series and a Rn-222 mass balance model. The results demonstrate that the average Rn-222 concentration measured by the Water Probe is only similar to 30% of that detected by means of the RAD AQUA. The mean SGD flux estimated based on Rn-222 time series measured with the Water Probe is 69% of that detected by means of the RAD AQUA. The findings of this study suggest that the RAD AQUA can capture more accurately the signals of variation of radon concentration, and is a better approach for continuously monitoring radon and quantifying SGD in coastal zones. Thus, previous studies based on Rn-222 data from the Water Probe for estimating SGD and the associated nutrient flux may need re-evaluation.

Submarine groundwater discharge Radon RAD AQUA Water Probe Instrumentation

SCI

英语

第一 ; 通讯

Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control[2017B030301012]

Geology ; Water Resources

Geosciences, Multidisciplinary ; Water Resources

WOS:000475982700025

SPRINGER

GEOSCIENCES

Web of Science

1.Southern Univ Sci & Technol, Sch Environm Sci & Engn, Guangdong Prov Key Lab Soil & Groundwater Pollut, Shenzhen 518055, Peoples R China
2.Southern Univ Sci & Technol, Sch Environm Sci & Engn, State Environm Protect Key Lab Integrated Surface, Shenzhen 518055, Peoples R China
3.China Univ Geosci, State Key Lab Biogeol & Environm Geol, Beijing 100083, Peoples R China
4.China Univ Geosci Beijing, Sch Water Resources & Environm, MOE Key Lab Groundwater Circulat & Environm Evolu, Beijing 100083, Peoples R China
5.Hebei GEO Univ, Sch Water Resources & Environm, Shijiazhuang 050031, Hebei, Peoples R China
6.UFZ Helmholtz Ctr Environm Res, Dept Groundwater Remediat, D-04318 Leipzig, Germany

Wang, Xuejing,Li, Hailong,Zhang, Yan,et al. Submarine groundwater discharge revealed by Rn-222: comparison of two continuous on-site Rn-222-in-water measurement methods[J]. HYDROGEOLOGY JOURNAL,2019,27(5):1879-1887.

Wang, Xuejing,Li, Hailong,Zhang, Yan,Qu, Wenjing,&Schubert, Michael.(2019).Submarine groundwater discharge revealed by Rn-222: comparison of two continuous on-site Rn-222-in-water measurement methods.HYDROGEOLOGY JOURNAL,27(5),1879-1887.

Wang, Xuejing,et al."Submarine groundwater discharge revealed by Rn-222: comparison of two continuous on-site Rn-222-in-water measurement methods".HYDROGEOLOGY JOURNAL 27.5(2019):1879-1887.