Tropical forest CH4: from termite mounds to tower measurements
- 1University of Bremen, Institute of Environmental Physics, Remote Sensing, Bremen, Germany (v_asperen@iup.physik.uni-bremen.de)
- 2Brazilian Agricultural Research Corporation (EMBRAPA) , Embrapa Amazônia Oriental, Belém, Brazil
- 3Coordenação de Dinâmica Ambiental (CODAM), Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus, Brazil, (currently at Vermont Agency of Natural Resources, Vermont-USA)
- 4Programa de Grande Escala da Biosfera-Atmosfera na Amazônia (LBA), Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus, Brazil
- 5Coordenação de Pesquisas em Entomologia (CPEN), Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus, Brazil
- 6Max Planck Institute for Biogeochemistry, Jena, Germany
- 7TNO, EMSA, Netherlands
Methane (CH4) is one of the most important anthropogenic greenhouse gases. Despite its importance, natural sources of methane, such as tropical wetlands and termites, are still not well understood and a large source of uncertainty in the tropical CH4 budget. The Amazon rainforest is a key region for the (global) CH4 budget but, due to its remote location, continous CH4 concentration and flux measurements are still rare.
The 50 m high K34 tower (field site ZF2) is located in a pristine ‘Terra Firme’ 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, an in-situ FTIR-analyzer (measuring CO2, CO, CH4, N2O and δ13CO2) was set up to measure tower profile concentrations, above and below the canopy, continuously. By analyses of vertical and temporal nighttime concentrations patterns, an emission estimate for all gases could be made, and an ecosystem emission of ~1 nmol CH4 m-2 s-1 was estimated. In addition, by use of different types of flux chambers, possible CH4 sinks and sources such as soils, trees, water and termite mounds were measured.
By combining tower and flux chamber measurements, the role and magnitude of different ecosystem sources could be assessed. In this presentation, an overview of the measured CH4 forest concentrations and fluxes will be given.
How to cite: van Asperen, H., Warneke, T., C De Araújo, A., Forsberg, B., Ramos de Oliveira, L., de Lima Xavier, T., Sá, M., Teixeira, P., Azevedo de Oliveira, R., Leal, L., Moura, V., Rafael Alves-Oliveira, J., Botia, S., Lavrič, J., Komiya, S., Frumau, A., Hensen, A., van Dinther, D., van den Bulk, P., and Notholt, J.: Tropical forest CH4: from termite mounds to tower measurements, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-13468, https://doi.org/10.5194/egusphere-egu21-13468, 2021.