This project aims to better understand resilience of natural forests in DR Congo to a changing environment. Therefore, the specific academic outcome is to develop state of the art biogeochemical and eco-hydrological research in representative forest biomes, hand in hand with inclusive education and outreach activities (= developmental objective). To achieve this we work in five forest sites in three different biomes. We study two forest types in tropical lowland rainforest (mixed and mono-dominant Gilbertiodendron forest in Yoko reserve, (0°17'39"N 25°17'20"E), two forest types in the tropical mountain forest (mixed and bamboo forest in Kahuzi-Biéga national park, (2°18'53"S 28°45'30"E), and Miombo semi-arid woodland at the southern border of the Congo Basin (Lubumbashi). In all sites, a fixed setup is operational for biogeochemical monitoring (e.g. through fall collectors, nutrient leaching and litter fall).
In this study, we test two recent nutrient and eco-hydrological paradigms using our permanent monitoring setup on several locations. First, the “leaky nitrostat” paradigm (Hedin et al., 2009) hypothesizes that in tropical forests N2 fixation relieves N limitations thereby securing carbon sequestration as an ecosystem function. However, an apparent up-regulation of N2 fixation, N release from weathering or enhanced N deposition from deforestation on savannah fires (Chen et al. 2010) (FORMONCO data: 30 kg N ha-1 yr-1 (50:50 DIN:DON) might generate an N-rich system, whereby P is limiting, leading to gaseous (N2O, NO and N2) and leaching (NO3-) losses. We will contribute here with research on biogeochemical-hydrological interactions in central African forests via four intermediate results: 1) interpretation of existing biogeochemical input/output data and continue data collection; 2) to investigate N and P biogeochemistry; and 3) to investigate water resource partitioning. Across all the scientific activities we develop concerted and inclusive capacity for research, education and outreach to better understand functions of forest ecosystems of DR Congo.