An optimum groundwater management which achieved a good balance between conser vation and utilization is required to use the groundwater as sustainable water resources. On the recent groundwater management which uses a numerical simulation, it is important to understand the full breadth of groundwater basin and groundwater storage for evaluation the extent of human impact. However, previous study has not been clarified the full breadth of them throughout Japan, because basic information on the groundwater has not maintained still enough. The present work developed the three dimensional hydrogeological model in Japanese islands using the related database. And the groundwater storage was estimated based on the three dimensional hydrogeological model. As a result, to evaluate the full breadth of groundwater basin became possible from the sharply widerange distribution of stratum. Moreover, we succeeded in providing the useful information such as development potential of unused groundwater resources for groundwater conser vation and development.
Submarine groundwater discharge (SGD) is considered to be the sustainable water resource, and also the important factor of the water cycle. Methods to evaluate the quantity of SGD can be divided into mathematical analysis and in-site survey, and in the case of wide area study, like the Japanese Islands, the macro evaluation by perennial water balance budget is suitable for the initial study. However, the evaluation of runoff using the River Discharge Year Book of Japan has several problems such as the uncertain accuracy of measurement, the existence of an inconsiderable area between the lowest flow gauge and river mouth, and unavailability of river flows in basins except for Class A rivers. In this paper, we calculated perennial water balances of 10 years in 204 regions on the Japanese Islands. It was the first time to make a distribution map of SGD in Japan. As there existed 144 regions where the flow data were insuff icient, the runoff in each area was estimated by the multiple linear regression analysis between the river flows and the recharges, divided by the geology of the basins where it was judged to be similar geologically by cluster analysis using area ratios of 43 geological classifications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.