研究期間：10304~10312;Groundwater is one of major water resources in Taiwan. Due to over pumping of groundwater for past decades, both Zhuoshui River Alluvial Fan and Pingtung Alluvial Plain have been facing critical issues of land subsidence and degradation of groundwater environments, such as sea water intrusion and contamination. Although subsurface water and surface water are naturally linked in view of hydrological cycles, great discrepancies in residence times and responses to different hydrological forcing are observed. Rainfall in Taiwan has great spatial and temporal variations and new water resources are difficult to develop due to environmental protections, and thus bring great challenges in water resources of Taiwan. Therefore it is important to develop integrated methodologies for taking advantages of various spatial and temporal characteristics of surface water and subsurface water to meet the requirement of sustainable development in water resources. In the first year (2014), we will first analyze characteristics of long-term decadal hydrological processes of the Zhuoshui River Alluvial Fan and reveal groundwater and surface water responses to various hydrological forcing and then apply WASH123D model to investigate hydrological characteristics of surface water and subsurface water. Three major topics will be studied for the Zhuoshui River Alluvial Fan, including (1) the relationship of hydrological responses between groundwater and surface water; (2) the characteristics of interactions between groundwater and surface water; and (3) the spatiotemporal changes patterns of groundwater levels responding to dry/wet years, extreme typhoon events, and anthropogenic pumping. Furthermore, we will perform a series of scenario simulations to suggest optimal solutions for artificial groundwater recharge near the apex of Zhuoshui River Alluvial Fan and the source area of Beigang River from options of artificial lakes, detention structure inside stream channel, ponds on the floodplain, or other candidate measures. Through these studies, it is expected to understand hydrological characteristics of groundwater and surface water systems for supporting effective management of water resources of Zhuoshui River Alluvial Fan.
