Comparison of GPP and Hydrological Organic Carbon Flux

This book presents a catchment scale case study investigation into the export of organic carbon through a river system in comparison with carbon that is produced by vegetation through photosynthesis. The research discusses the use of a hydrological simulation model to analyse organic carbon samples from stream and tributaries. The gross primary productivity of the vegetation cover in the catchment was estimated using a radiation use efficiency model driven by MODIS TERRA data on vegetation greenness and modeled surface irradiance. The relationship between total organic carbon discharged in-stream and total carbon uptake by plants was assessed using a cross- correlation analysis. The results of the hydrologic modeling approach and terrestrial GPP outcome were compared. This comparison revealed the likely proportion of catchment GPP that contributes to in-stream hydrological flux of organic carbon. Total Organic Carbon Load was 0.45% of GPP. As a result, it can be concluded that the hydrological flux of organic carbon in a forested catchment is a function of gross primary productivity.