Coastal blooms of phytoplankton induced by land-based nutrient loading was cited in the TDA Report as one of the top priority impacts of land-based pollution in the South China Sea. However, it was recognised that different marine areas could have different capacity to assimilate nutrients and therefore not all nutrient delivered from nearby land masses will result in such blooms.

Carrying capacity can be estimated by several approaches, some are qualitative while others can be very quantitative. The South China Sea Project adopted a quantitative modeling approach, and Dr. Anond Snidvongs conducted research in support of the Project that was aimed at quantitatively linking surface phytoplankton biomass as indicated by chlorophyll and surface water concentration of dissolved oxygen with nutrient loading by rivers. Once the model was satisfactorily calibrated, assimilation capacity was estimated by perturbing the system with some imaginary loading scenarios. A valuable output of this South China Sea Project activity is a gridded (raster) based chlorophyll modelling system as a functional response to land-based nutrient loading that runs entirely on Microsoft Excel (including data management, numerical solving and geospatial visualisation).

This South China Sea Nutrient Carrying Capacity model can be accessed by clicking here. A comprehensive user manual outlining the procedures for downloading model data from UNEPSCS.org, running the model, and modifying nutrient loading scenarios can be accessed by clicking here.

While considerable effort has gone toward making this tool as useful as possible, we welcome constructive feedback on how the interface or user manual might be improved. Users are encouraged to contact the PCU in the case of any error, or to suggest additional information that might be useful.

Please forward your comments to the Director of SEA START RC, This e-mail address is being protected from spam bots, you need JavaScript enabled to view it , or the South China Sea Project's Fisheries Expert, This e-mail address is being protected from spam bots, you need JavaScript enabled to view it .