Evaluations of carbon and dissolved material material transport by submarine groundwater discharge in coastal zone of East Asia

海底地下水排放（SGD）是陆地向海洋输送水和溶解物质的重要途径，也是海岸带生态系统的重要通道。在东亚的几个国家，包括韩国、台北、曼谷、马尼拉和大阪，进行了渗水计（用于测量SGD通量）、压电计（用于测量地下水潜力和溶解物质输送）、光缆（用于测量海底温度）和电阻率（淡水-盐水分布）测量，以评估SGD通量和质量。最近采取了一种多学科方法来评估地下水渗漏对菲律宾马尼拉湾营养物输入的潜在重要性。在2005年1月8日至10日期间，在巴丹省Mariveles沿岸的横断面安装了三条渗水计。沿最北线的渗流速率最大，为7.1 ~ 10.9 cm day^<-1>。总体平均渗流通量为5.1±5.4 cm/d，范围为0 ~ 26cm/d。采用的其他方法包括自动渗透仪、电阻率测量和使用天然氡作为地下水示踪剂。渗透仪和示踪剂的结果提供了马尼拉湾SGD估计的一致结果。两种方法还表明，渗流通量不是稳态的，而是受潮汐的调制。电阻率剖面显示，咸水界面在潮汐时间尺度上移动。我们的研究结果表明，通过SGD的溶解无机氮（DIN）通量与流入马尼拉湾的两条主要河流的DIN通量相当

Submarine groundwater discharge (SGD) is recognized as an important pathway from land to ocean, not only for water and dissolved material transports but also for ecosystem in the coastal zone. The seepage meters (for SGD flux), piezometers (for groundwater potential and dissolved material transports), optic fiber cable (for sea bottom temperature) and resistivity (fresh-salt water distribution) measurements had been made to evaluate the flux and quality of the SGD in several palaces in East Asia, including, Korea, Taipei, Bangkok, Manila, Osaka.A multidisciplinary approach was recently taken to assess the potential importance of groundwater seepage to nutrient inputs into Manila Bay, The Philippines. Three lines of seepage meters were installed in transects along the coast at Mariveles, Bataan Province during the period between 8-10 January 2005. The seepage rates along the northern most line showed the highest submarine groundwater discharge (SGD) at rates of 7.1-10.9 cm day^<-1>. The overall average seepage flux was 5.1±5.4 cm/day with a range of 0-26cm/day. Additional methodologies employed included automatic seepage meters, resistivity measurements, and use of natural radon as a groundwater tracer. Seepage meter and tracer results provided consistent results of estimates of SGD into Manila Bay. Both methods also showed that seepage fluxes are not steady-state but are modulated by the tides. Resistivity profiles show that the saline-freshwater interface moves on a tidal time scale. Our results show that dissolved inorganic nitrogen (DIN) fluxes via SGD are comparable in magnitude to DIN fluxes from each of the two major rivers that drain into Manila Bay