Aquatic nutrient exports from tropical forests in the Congo Basin Simon Baumgartner


May 17, 2021

13h on teams

Tropical forests play an important role in the global carbon cycle and represent a significant CO2 sink. Maintaining this function requires a large and sutained availability of nitrogen (N). As a result, understanding N cycling is crucial for the assessment of future productivity of tropical forest ecosystems. Particulate organic N (PON) export is potentially an important loss in tropical landscapes, however, the lack of studies targeting PON losses, and overal N species composition in catchment-scale export across forest types, is a large knowledge gap. We measured annual nutrient exports from three different forested ecosystems of the Congo Basin, focussing on the erosion driven losses of PON. Preliminary results showed that in a tropical lowland forest and subtropical Miombo woodlland around 43% and 44% of the total exported N is lost as PON, while in a more geomorphic active montane forest up to 60 % of the total exported N is lost as PON. These findings highlight the need to include PON in N budget calculations of tropical forests.