4:30 PM - 4:45 PM
[ACG39-11] Impacts of experiment warming on soil CO2 emissions and CH4 uptake in Japanese forests
Keywords: Warming effects, Soil CH4 uptake, soil CO2 emissions, chamber, soil moisture
*Lifei Sun1, Naishen Liang1, Kentaro Takagi2, Sachinobu Ishida3, Masahiro Takagi4, Munemasa Teramoto5, Toshiaki Kondo6, Jun Koarashi7, Mariko Atarashi-Andoh7, Jiye Zeng1, Takashi Hirano2, Yoshiyuki Takahashi1
1. National Institute for Environmental Studies, 2. Hokkaido University, 3. Hirosaki University, 4. University of Miyazaki, 5. Tottori University, 6. Japan International Research Center for Agricultural Sciences, 7. Japan Atomic Energy Agency
Methane (CH4) is the second most important greenhouse gas (GHG) after carbon dioxide (CO2) that contributing to human-induced global warming. CH4 has a Global Warming Potential 86 and 28 times larger than CO2 for time horizons of 20 and 100 years. According to the fifth IPCC report, the increasing GHG emissions are expected to raise global temperature from 2.6 to 4.8 °C by the end of this century. Soil CO2 emissions accounts for about 80% of total forest ecosystem respiration, whereas CH4 is absorbed by forest soil as the most efficient sink. The warming effects of soil CO2 emissions have been shown different pattern due to distinction of soil organic carbon (SOC), precipitation, soil moisture, quantity and thermal adaptation of microbe by warming experiments. However, research on variation of CH4 uptake with global warming is still rare.
To investigate warming impacts on soil CO2 emissions and CH4 uptake, in 2021, we conducted warming experiment with multi-channel automated chamber measurement system in five forests from northern Hokkaido to Miyazaki. The experiment was designed with two treatments including trenching (control for heterotrophic respiration: Rh) and trenching plus warming (warmed Rh: Rhw) each with five replications. Soil CO2/CH4 fluxes were measured and analyzed at hourly intervals.
We could not detect 10-cm soil moisture changes between control and warmed plots in all sites. Rhw-CO2 were significantly higher than Rh-CO2 in all sites. Similarly, higher Rhw-CH4 than that of Rh-CH4 were shown in all sites except for red pine forest Tsukuba with andosol. Seasonal variation of CH4 flux was more sensitive to soil moisture than that of CO2 efflux. Results demonstrated that both soil CO2 emissions and CH4 uptake can be enhanced by changing microbial activity or soil surface moisture through warming treatment. This presentation will show the site-specifications of warming effects on soil CO2 emissions and CH4 uptake.
1. National Institute for Environmental Studies, 2. Hokkaido University, 3. Hirosaki University, 4. University of Miyazaki, 5. Tottori University, 6. Japan International Research Center for Agricultural Sciences, 7. Japan Atomic Energy Agency
Methane (CH4) is the second most important greenhouse gas (GHG) after carbon dioxide (CO2) that contributing to human-induced global warming. CH4 has a Global Warming Potential 86 and 28 times larger than CO2 for time horizons of 20 and 100 years. According to the fifth IPCC report, the increasing GHG emissions are expected to raise global temperature from 2.6 to 4.8 °C by the end of this century. Soil CO2 emissions accounts for about 80% of total forest ecosystem respiration, whereas CH4 is absorbed by forest soil as the most efficient sink. The warming effects of soil CO2 emissions have been shown different pattern due to distinction of soil organic carbon (SOC), precipitation, soil moisture, quantity and thermal adaptation of microbe by warming experiments. However, research on variation of CH4 uptake with global warming is still rare.
To investigate warming impacts on soil CO2 emissions and CH4 uptake, in 2021, we conducted warming experiment with multi-channel automated chamber measurement system in five forests from northern Hokkaido to Miyazaki. The experiment was designed with two treatments including trenching (control for heterotrophic respiration: Rh) and trenching plus warming (warmed Rh: Rhw) each with five replications. Soil CO2/CH4 fluxes were measured and analyzed at hourly intervals.
We could not detect 10-cm soil moisture changes between control and warmed plots in all sites. Rhw-CO2 were significantly higher than Rh-CO2 in all sites. Similarly, higher Rhw-CH4 than that of Rh-CH4 were shown in all sites except for red pine forest Tsukuba with andosol. Seasonal variation of CH4 flux was more sensitive to soil moisture than that of CO2 efflux. Results demonstrated that both soil CO2 emissions and CH4 uptake can be enhanced by changing microbial activity or soil surface moisture through warming treatment. This presentation will show the site-specifications of warming effects on soil CO2 emissions and CH4 uptake.