Japan Geoscience Union Meeting 2025

Presentation information

[J] Oral

A (Atmospheric and Hydrospheric Sciences ) » A-CG Complex & General

[A-CG46] Biogeochemical Cycles in Land Ecosystem

Tue. May 27, 2025 9:00 AM - 10:30 AM Exhibition Hall Special Setting (3) (Exhibition Hall 7&8, Makuhari Messe)

convener:Munemasa Teramoto(Arid Land Research Center, Tottori University), Tomomichi Kato(Research Faculty of Agriculture, Hokkaido University), Kazuhito Ichii(Chiba University), Takeshi Ise(FSERC, Kyoto University), Chairperson:Munemasa Teramoto(Arid Land Research Center, Tottori University)

10:00 AM - 10:30 AM

[ACG46-05] Launching a new biogeochemical research network in tropical Asia

★Invited Papers

*Masayuki Kondo1,2 (1.The IDEC Institute, Hiroshima University, 2.Seto Inland Sea Carbon-neutral Research Center, Hiroshima University)

Keywords:Tropical Asia, Greenhouse Gases, LeXta

Tropical Asia is a region that has attracted attention in various fields related to biogeochemical cycles, including ecology, atmospheric chemistry, climatology, and geology. The region's climate is highly sensitive to climate modes such as El Niño Southern Oscillation (ENSO) cycle, Indian Ocean Dipole (IOD), and East Asian monsoon. These climate modes result in periodic and episodic dry periods that are often accompanied by human-induced fires. Fires are particularly severe when they occur in tropical peatlands and can cause widespread greenhouse gases (GHG) and toxic haze. It is also known that the vegetation in this region responds strongly to the phase of ENSO, greening during droughts caused by El Niño and browning during humid conditions caused by La Niña. However, the uptake and emission of CO2 shows the exact opposite reaction to greening and browning. Furthermore, tropical Asia is a region of active volcanism, and it is known that GHG, such as CO2 and CH4, seepages from the earth's crust are at high levels. In addition to the above, the most serious concern is human activity in forest ecosystems. Persistently active land-use activities for years such as unmanaged deforestation and agricultural development in this region in particular are considered to be one of the factors accelerating the risks of global warming.
To address these various biogeochemical cycle challenges in tropical Asia, we have launched an international network called the League of geophysical research eXcellences for tropical Asia (LeXtra). We are an organization made up of researchers from Asia, working in collaboration with local researchers. Our objectives are to fundamentally review the biogeochemical cycles in tropical Asia, to elaborate on the GHG uptake and emission processes that have been overlooked so far, and to calculate the greenhouse gas budget in each country that has ratified the Paris Agreement.