In 2014, the Gabon-Oregon Center awarded a seed grant to a team looking to study methane dynamics in tropical wetlands, as methane is a powerful greenhouse gas contributing to global climate change. This work builds on initial research by the joint Gabon-Oregon team studying microbial biodiversity in tropical rainforests.
In the Fall of 2014, UO professors Scott Bridgham and Brendan Bohannan traveled to Gabon with UO Biology graduate students Anya Hopple and Kyle Meyer to work with the Gabonese researcher Dr. Rolf Mabicka Obame of the University of Science and Technology of Masuku in Franceville, Gabon. The team examined controls over methane dynamics in 17 sites in the Rabi and Gamba areas of Gabon that included upland forests, new and abandoned plantations, grasslands, and a variety of wetlands.
The team measured net flux rates of methane and carbon dioxide, added a stable isotope of methane to determine gross rates of methane production and consumption, and preserved samples for DNA and RNA analysis of microbial communities with high-throughput techniques and quantitative PCR. Soil samples were also brought back to UO where we measured rates of methane oxidation and the two pathways of methane production, along with collecting samples for microbial community analysis.
This pilot data was used for a preliminary proposal to NSF that was successful, and a full proposal was submitted in July 2015. The data collected from this project will also result in a dissertation chapter for each of the Ph.D. students, and we expect will result in two peer-reviewed publications. In August 2015, Dr. Rolf Mabicka Obame traveled to Gabon to spend three months in Dr. Bridgham's lab examining shifting agriculture effects on soil carbon and nutrient cycling. With Gabon-Oregon Center funding, Dr. Mabicka Obame purchased the equipment and computer necessary to set up a similar lab in the city of Franceville, Gabon, in order to perform this research and train his Gabonese colleagues.
This work has important implications for understanding one of the key drivers of climate change, the greenhouse gas methane, and its dynamics in tropical wetlands. This region in Gabon, and the continent of Africa more generally, has been understudied in this field and the GOC-funded team will attempt to close some important gaps in our knowledge of methane cycling in the tropics.