[A-CG40] Coastal Ecosystems - 1. Water Cycle and Land-Ocean Interactions

[ACG40-04] Spatial and Temporal Patterns of the Physical and Biogeochemical Properties in the Nearshore Waters of Toyama Bay

*Eligio de Raus Maure¹, Genki Terauchi¹, Yasuyuki Harada¹ (1.Northwest Pacific Region Environmental Cooperation Center)

Keywords:Toyama Bay, Physical and Biogeochemical Properties , Nearshore Waters

Toyama Bay, located in the Japan Sea, has a very steep bottom topography with depths greater than 200 m confined to the narrow shelf. The outflow from rivers plays an important role in the physical and biological dynamics of coastal waters. Thus, it is important understand the influence of the river discharge on the spatial and temporal variations of material cycle and productivity in nearshore waters. Previous research using satellite observations of chlorophyll-a concentration suggested in the river discharge influenced waters, the phytoplankton bloom was characterized by a strong summer peak that correlated with river discharge. Although the river discharge can also be high or higher in seasons other than summer, it is not yet clear what is the influence on the spatial and temporal variations of phytoplankton during non-summer periods. In this study, we summarize the long-term in-situ observations collected by the Northwest Pacific Region Environmental Cooperation Center (NPEC) in Toyama Bay to gain insights of the influence of river discharge on the spatial and temporal patterns of physical and biogeochemical properties of the innermost waters. For this purpose, this presentation will discuss the spatial and temporal patterns obtained from monthly observations of temperature, salinity, chlorophyll-a concertation and dissolved inorganic nutrients (nitrogen and phosphorus), collected since 2004 to present in the Toyama Bay.