The relationship of DOC/CDOM

The relationship of DOC/CDOM Jiwei Li 1 , Qian Yu 1 , and Yong Q. Tian 2, 3 1 Department of Geosciences, University of Massachusetts, Amherst. 2 Institute for Great Lakes Research, Central Michigan University. 3 Department of Geography, Central Michigan University. Key Points: The relationship of DOC/CDOM is impacted by the land cover types and temperature. The same CDOM indicates different DOC levels according to watershed land covers and seasons. Abstract The DOC flux from terrestrial to aquatic environment can be monitored at high spatial-temporal resolution through the remote sensing estimation of CDOM. To improve the reliability of DOC remote sensing monitoring, the co-variation of the DOC and CDOM were examined in a series novel mesocosm experiments and six years watershed field samplings. Both the mesocosm experiments and field samplings found the relationships of DOC/CDOM were impacted by land cover types and temperature. The same CDOM absorption represents different levels of the DOC concentra tion for the different vegetation (rank as evergreen, agriculture and deciduous). Meanwhile, the CDOM absorption correlated to high DOC levels in high temperature. Our findings significantly improves efficiency for using the CDOM as the DOC proxy. 1 Introduction The terrestrially derived dissolved organic carbon (DOC) inputs a large amount of carbon (2 gigatons) to the aquatic ecosystems each year [ Battin et al. , 2009 ]. More than 1 gigaton ofÂÂ   DOC released to the atmosphere when they are carried through the inland water systems, including the rivers, lakes, and ponds [ Roulet and Moore , 2006 ]. Both the rivers and non-running inland waters (lakes and ponds) actively transform the DOC to the CO2 in the atmosphere [ Holgerson and Raymond , 2016 ]. This DOC flux is the crucial components in the global greenhouse gas budget [ Pachauri et al. , 2015 ]. The input of DOC to inland water and oceans can account for considerable carbon loss from terrestrial ecosystems, which has l arge implications for regional carbon cycling by changing the terrestrial net ecosystem exchange [ Borken et al. , 2011 ; Kindler et al. , 2011 ]. The terrestrial DOC inputs to the aquatic ecosystems also plays an important role in the water quality, controlling metal binding and transport, and modifying nutrients dynamics due to its labile properties in aquatic environments [ Bianchi et al. , 2015 ; Stedmon et al. , 2006 ]. The DOC transport from land to water has remarkable implication on the carbon cycle, biogeochemical processes, and ecological processes at regional and global scale [ Butman and Raymond , 2011 ; Raymond and Bauer , 2001 ; Spencer et al. , 2013 ]. This DOC flux is required to be monitored at high spatial Fichot and Benner , 2011 ; Vodacek et al. , 1997 ]. The CDOM is the colored components of the dissolved organic matter (DOM) in the water [ Del Vecchio and Blough , 2004 ], which changes the in-water light field through the strong absorption of short wavel ength light [ Rochelle-Newall and Fisher , 2002 ]. The CDOM absorption can be estimated through the detecting of the in-water light field to provide the high spatial-temporal resolution water carbon information [ Jiwei Li , 2016 ].