Abstract
Prototype model to quantify transport of land derived dissolved organic carbon was proposed as a simple future projection method in Kushiro River basin where various land usage, such as forest, pasture, wetland, farmland, etc., were distributed like a mosaic. By field observation in a part of upstream reach and a river mouth of Kushiro River, non-point source load of dissolved organic carbon from Kushiro River basin with huge carbon potential were determined throughout the year including snowmelt season. By incorporating the output of general circulation models of CMIP5 to simple hydrological model in DOC transport, the increase trend of DOC discharge to the marginal sea were estimated with partially-seasonal decrease.
