Wetlands in East Africa: Reconciling future food production with environmental protection
In the frame of the BMBF-funded project “Wetlands in East Africa: Reconciling future food production with environmental protection” (www.wetlands-africa.de), this PhD project aims at quantification of trace gas fluxes as sustainability indicators of different land uses in East African wetlands. The two focus regions are Namulonge in Uganda and Ifakara in Tanzania. At these two sites, different agricultural management options will be implemented by the project collaborators, and soil-atmosphere gas fluxes will be utilized as sustainability indicators, i.e., CO2 as an indicator of soil organic matter stability, NH3 and N2O as indicators of the closeness or openness of the nitrogen cycle (nitrogen retention), and CH4 as an indicator of the redox status of the soil. At the respective field sites, soil-atmosphere CO2 fluxes will be quantified on site with a portable analyzer with a dynamic chamber. N2O and CH4 fluxes will be determined with static chambers and gas chromatography. NH3 losses will be estimated with passive samplers at selected sites where high fluxes can be expected, and with empirical equations for all sites. Quantification of N2O losses, as well as experiments for parameterization of gaseous soil C and N losses, will be performed with intact soil cores taken at the field sites and transported to the laboratory in Germany.