C-CASCADES has covered all key components of the LOAC, that is, terrestrial ecosystems, streams, rivers, lakes and reservoirs, estuaries and river plumes as well as the coastal and open oceans. These interconnected compartments of the LOAC have been studied across a wide-range of environments – from the Pan-Arctic down to the Tropics and from near-pristine systems in the boreal region to catchments in temperate regions heavily impacted by human activities. The dynamics of all major organic and inorganic carbon pools have also been investigated through the full range of methodological approaches, from field observations using cutting-edge sensor technology, to mesocosms experiments, and further to highly detailed process-based modeling, as well as statistical and Earth System modeling. In addition to regional scale studies, C-CASCADES has analyzed several major carbon fluxes and processes at the global scale. This includes, for instance, DOC leaching from terrestrial soils into inland waters, headwater, rivers, floodplains and lake CO2 evasion, the 20th century changes in the CO2 exchange at the air-sea interface of coastal and open ocean waters and present-day carbon fluxes for the LOAC, in the context of the global carbon budget.
Significant progress in LOAC science has been achieved, described below for each Work Package:
WP1 - Process understanding: Technical development, observations and experiments:
• Sensors able to continuously measure CO2, CH4 and O2 concentrations across the full river-ocean mixing regime are available
• Inland waters play a very important role in the lateral carbon flux along the LOAC and in GHG emissions. While mountain streams and boreal waters seem to receive large parts of their gas concentrations from catchment soils and via groundwater, urban waters show deviating patterns and sources
• Temporal trends in natural waters show presently no overall significant increases in greenhouse gas concentrations in the waters
WP2 – Regional scale applications: benchmark studies on hot-spot areas:
• The discovery of the complex space-time nature of the carbon dynamics in a river delta system
• Novel and improved quantification of the Arctic carbon fluxes
• First quantification of the role of the Amazon river supply of nutrients for the productivity of the entire Atlantic ocean
• A novel sedimentary model for the Arctic which includes many key processes
WP3 – Global scale modelling and feedbacks on Earth system processes:
• Assessment of past, present-day and future global-scale terrestrial DOM (tDOM) production, decomposition and leaching to aquatic ecosystems, and its imprint on the global coastal and open ocean C cycle. Quantification of organic matter recycling and burial in marine sediments, the ultimate C incinerator along the LOAC
• Assessment of past, present-day and future role of the LOAC for the carbon balance and CO2 emissions of Pan-Arctic, boreal and tropical catchments
Exploitation and dissemination of C-CASCADES results:
• 27 peer-reviewed articles published, about an additional 30 to come
• 31 posters and 22 oral communications at international conferences
• Outreach products were produced for Stakeholders and the general public: website, videos, factsheets, “LOAC emissions” module on the Global Carbon Atlas (
http://www.globalcarbonatlas.org/(öffnet in neuem Fenster)).
• Inter-sectorial partners valorised our results in a context useful to improved environmental consulting and industrial/commercial development (modelling platform DELWAQ, sensors by KM Contros, wastewater treatment strategies at Veolia)
