TY - GEN
T1 - Estimation of groundwater discharge to the sea using a distributed recharge model
AU - Katsuki, M.
AU - Yasumoto, J.
AU - Tsutsumi, A.
AU - Hiroshiro, Y.
AU - Jinno, K.
PY - 2009
Y1 - 2009
N2 - Groundwater discharge to sea areas affects environmental conditions along coasts. Enclosed bays may experience eutrophication caused by nutrient input from land areas through groundwater discharge since groundwater is often contaminated by large amounts of nutrients as compared with river water. Therefore, it is necessary to estimate the groundwater discharge into seas quantitatively in order to understand nutrient pathways. A distributed groundwater recharge model was developed in order to estimate total groundwater discharge flow into the Ariake Bay, in Kyushu, Japan. The Komoda catchment within the Kikuchi River basin in Kumamoto prefecture was studied as a representative area for the Ariake Bay. The model partitions rainfall into direct runoff, evapotranspiration, and groundwater recharge. Parameters are set based on land use. Groundwater discharge is calculated using a water balance approach. The results show that groundwater discharge into the Ariake Bay from Kukuchi River basin is on average 123 mm year-1. The groundwater discharge accounts for about 8% of total water discharge and 9% of river discharge. The results can be used to better estimate annual transport of nutrients in the groundwater to the sea and thus also to better manage eutrophication problems.
AB - Groundwater discharge to sea areas affects environmental conditions along coasts. Enclosed bays may experience eutrophication caused by nutrient input from land areas through groundwater discharge since groundwater is often contaminated by large amounts of nutrients as compared with river water. Therefore, it is necessary to estimate the groundwater discharge into seas quantitatively in order to understand nutrient pathways. A distributed groundwater recharge model was developed in order to estimate total groundwater discharge flow into the Ariake Bay, in Kyushu, Japan. The Komoda catchment within the Kikuchi River basin in Kumamoto prefecture was studied as a representative area for the Ariake Bay. The model partitions rainfall into direct runoff, evapotranspiration, and groundwater recharge. Parameters are set based on land use. Groundwater discharge is calculated using a water balance approach. The results show that groundwater discharge into the Ariake Bay from Kukuchi River basin is on average 123 mm year-1. The groundwater discharge accounts for about 8% of total water discharge and 9% of river discharge. The results can be used to better estimate annual transport of nutrients in the groundwater to the sea and thus also to better manage eutrophication problems.
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M3 - Conference contribution
AN - SCOPUS:79952322981
SN - 9780415472791
T3 - From Headwaters to the Ocean: Hydrological Changes and Watershed Management - Proceedings of the International Conference on Hydrological Changes and Management from Headwaters to the Ocean, HYDROCH
SP - 625
EP - 630
BT - From Headwaters to the Ocean
T2 - International Conference on Hydrological Changes and Management from Headwaters to the Ocean, HYDROCHANGE 2008
Y2 - 1 October 2008 through 3 October 2008
ER -
