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.