Profile and flux measurements of methane in the Amazon rainforest.
Abstract
Methane (CH4) is the second most important long-lived anthropogenic atmospheric greenhouse gas, but its natural sources are still not well understood. One source of uncertainty is the role of wetlands, which are estimated to be responsible for 25-50% of the global CH4 emissions. The Amazonian rain forest is estimated to hold 90-120 Pg of carbon, which is approximately 14-27% of the carbon stored in vegetation worldwide. The region is characterized by high precipitation rates and large wetlands, and it has been estimated that the Amazon basin emits 7% of the annual total CH4 emissions. Due to its remote location, micro-meteorological measurements are rare and absent for other gases than CO2. The 50 m high K34 tower (field site ZF2) is located in a pristine tropical forest region 60 km northwest of Manaus (Brazil), and is located next to a waterlogged valley, a possible location for anaerobic CH4 production. In October 2018, in addition to the existing EC CO2 system, a Relaxed Eddy Accumulation (REA) system was set up at this tower, connected to an in-situ FTIR-analyzer. This set up measures fluxes and concentration profiles of CO2, CO, CH4, N2O and δ13CO2. In addition, by use of flux chambers, CH4 and CO2 fluxes of soils and rivers will be measured in the footprint of the REA measurements. This combination of measurements will provide inside in ecosystem CH4 uptake and emission processes and their driving factors. In this presentation, the first results of these field measurements will be shown.
- Publication:
-
EGU General Assembly Conference Abstracts
- Pub Date:
- April 2019
- Bibcode:
- 2019EGUGA..2117124V