Workshop

FY2024 FNCA Workshop on Climate Change (Evaluating the Carbon Emission from Forest Soils: ECEFS) project was held from October 15 to 17, 2024, in Hiroshima city of Japan. This Workshop was hosted by Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan.

The Workshop was attended by 29 participants from 8 FNCA member countries, namely, China, Indonesia, Japan, Kazakhstan, Malaysia, the Philippines, Thailand, and Vietnam, including workshop secretariats.

Open Seminar

The open seminar was held in the morning on October 17^th.
Dr. TAMADA Masao, FNCA Coordinator of Japan, overviewed activities on FNCA. Dr. LIANG Naishen, NIES, introduced response and feedback of Asian forest soil to global warming. Dr. KONDO Toshiaki, Japan International Research Center for Agricultural Sciences, outlined soil organisms that release and absorb greenhouse gases. Lastly, Prof. MATSUZAKI Hiroyuki, the university of Tokyo, presented ¹⁴C measurement by Accelerator Mass Spectrometry.

Technical Visit (Field Work)

Technical Visit was held in the afternoon on October 17^th in Higashi-Hiroshima city. Drs. KOARASHI Jun and LIANG Naishen guided participants to a soil-warming-experiment forest site. Dr. LIANG Naishen introduced a unique chamber system for continuously monitoring the soil CO₂ flux and its response to warming. Then Japan research team demonstrated soil sampling method.

Opening Session

Ms. NAKAHARA Risa, Administrative Researcher of International Nuclear and Fusion Energy Affairs Division, Research and Development Bureau, Ministry of Education, Culture, Sports, Science and Technology (MEXT), delivered welcoming remarks. Then Dr. TAMADA Masao, FNCA Coordinator of Japan expressed opening remarks

Session 2

Dr. NAGAI Haruyasu, FNCA Climate Change (Evaluating the Carbon Emission from Forest Soils) Project Leader of Japan, outlined activities of the Project: background, objective, vision, goals and overall schedule. He also summarized the achievement in the first year of the project and explained major topics to be discussed during the workshop.

Session 3

Country reports were given by 8 member countries.

China

Soil organic carbon (SOC) residence time and dynamics are critical indicators for assessing the dynamics of SOC cycling. Currently, ¹⁴C is the only tool capable of addressing SOC dynamics over longer timescales, ranging from decades to millennia. This report presents case studies on the application of radioactive isotope ¹⁴C concerning SOC residence time and dynamic changes in Chinese forest soils, including: variations in SOC residence time and influencing factors at the sampled scale, the impact of spatial heterogeneity of litter distribution on SOC residence time, dynamic changes in soil microbial carbon along elevation gradients, biological community structure and organic carbon dynamics in natural forests along climatic gradients, and the effects of forest conversion on the turnover status of microbial organic carbon in forest soils. Additionally, this report provides the progress, plans, and soil export related to the FNCA project in China. Overall, there is high potential for the application of ¹⁴C technology in China. This report aims to integrate the application of ¹⁴C in Chinese forest soils with the FNCA project to jointly contribute to the study of SOC characteristics at an Asian scale and to predict the feedback effects of carbon cycling on global warming.

Indonesia

Our research center has been doing soil CO₂ emission study since 2017 using C-13 isotope in combination with Rn-222. However, the study is more focused on permeability zones rather than global warming study. Regarding the FNCA project (ECEFS) status, we selected two sites for sampling in Java Island. The first is located in West Java (priority) which is a tropical sub-montane forest at about 800 masl elevation. The second site is located in East Java which is also a tropical forest at about 1200 masl elevation. Both sites have more than 2000 mm of mean annual precipitation. Sampling activity has not been done, because the sampling kit is not arrived yet.

Japan

We have developed an experimental kit, enabling all participants in the project to conduct experimental work regarding soil sampling and soil incubation with a unified method. We have distributed the kit to the participants to construct Asian-scale data on the CO₂ emission from forest soils and its sensitivity to rise in temperature. We have developed the research team in Japan to analyze soil and gas samples and to explore factors that control the CO₂ emission from forest soils in Asia.

Kazakhstan

The research of carbon dioxide emissions from soils is important for Kazakhstan, because this problem is exacerbated by arid climate. Due to the large distance between some research sites and our laboratory, we propose leaving only three research sites: Bayanaul, Dolon, and Kanonerka. This will allow us to begin the incubation experiment on the day of sampling according to the Instruction Guide of FNCA. In 2024 we collected soil samples from 2 research sites: Dolon, Kanonerka. However, this is a relatively new topic for National Nuclear Center, and we intend to collaborate with organizations with more experience in the field.

Malaysia

Carbon dioxide (CO₂) already well known to be the main cause for climate change and global warming. However, the release of CO₂ into the atmosphere, not only by human industrial revolution, but could also be caused by natural process such as microbial decomposition of soil organic carbon (SOC) from the forest soils. More than half of Malaysia's land is covered by forests. Most of the forest is located on the East Malaysia, at the Borneo Islands while lesser on the west, The Peninsular. The majority of Malaysian forests are made up by different types of Dipterocarp forest, follow by smaller portions of Peat Swamp forest and Mangrove forest. To fulfil the needs and target of the FNCA project to evaluate the contribution from forest soil to the carbon emission, three locations had been identified for collection of the forest soil, i.e. Dengkil and Bukit Merah, both at low land and Cameron Highland at the high land. Soil from Dengkil had been collected in September 2024. The sample was prepared and ready to be send to Japan for further analysis. Additional sample was also collected to study some characteristics locally. Sampling at the other two sites will be commenced next year. With all this data, hopes it can contribute to the project and help to understand the carbon cycle on the terrestrial ecosystem.

The Philippines

The project team has selected five sites of tropical moist forest dominated by mixed native forest species. These areas have about similar main annual temperatures of approximately 27ºC and receive more than 2,200 mm of rainfall per year. The selected sites are in 1) VSU, Baybay, Leyte; 2) Cuyambay, Tanay, Rizal; 3) Rodriguez, Rizal; 4) Payatas; and 5) Lagro, both in Quezon City. Initial site visits and a preliminary site survey have been conducted. Soil samples were collected and described, with four composite samples taken per site and duplicates of cored samples for bulk density determination. The soil samples were air-dried, pulverized using a soil grinder, and sieved through 2-mm and 0.425-mm meshes. Physicochemical characterizations (water holding capacity, bulk density, texture, aggregate stability, pH, electrical conductivity, available P, exchangeable bases, exchangeable acidity and Al, effective cation exchange capacity, base saturation, and available micronutrients, and total elemental analysis) of the soil samples collected were done following standard methodologies. Incubation of fresh soil samples to be collected at each site will commence in November to December 2024. Gas and soil samples shall be collected from the incubation experiment and be sent to Japan for further analysis.

Thailand

The integrated approach of stable carbon isotopes and radioactive (¹⁴C) as tracers in studying carbon cycling in forest soil and its response to global warming was determined to be done in Phrae Province, North Thailand. Two study sites of deciduous dipterocarp forest (Mae Pak Phan Forest 17° 59' 4" N, 99° 38' 57" E), Den Chai District and mixed forest (Mae Khum Mee Forest 18° 15' 36" N, 100° 14' 2" E), Rong Kwang District are selected. The main soil types of both locations are Acrisols, Fluvisols and Arenosols. The first sampling campaign has been planned for early February 2025 and further analysis of stable carbon isotopes and environmental parameters will be carried out. A trial on an experimental kit was successfully conducted in the wood area of TINT. Due to the severe flooding in north Thailand recently, research funding has been cut down. However, the request for funding will be made again in 2025.

Vietnam

In 2024, while implementing the project, we collected several experimental forest soil samples. The areas from which samples were collected include Nam Cat Tien National Park, Bidoup - Nui Ba in Lam Dong, and Nui Chua in Ninh Thuan. In the near future, we will continue to collect samples from the remaining two locations, Yok Don and Phong Nha-Ke Bang National Park. Plans to send the samples to Japan will be developed after discussions with the research team there.

Session 4

A lead speech was delivered by Dr. KOARASHI Jun, Japan Atomic Energy Agency or JAEA, and lecture about CO₂ emission from forest soils was presented by Dr. LIANG Naishen, National Institute for Environmental Studies or NIES, then setting off a discussion on the research plan and schedule of experiments.
After discussion, the participants confirmed the followings.

1. Scientific knowledge about climate change and SOC dynamics were shared, and the participants understood what we will do in the project and how we can contribute to the climate change research.
2. Detailed procedure and problems in using Experimental Kit were discussed, and the participants confirmed the procedure (start time of incubation, how to keep samples, when to send samples to Japan, etc.) and how to deal with problems.
3. In the schedule of experiments, the deadline of sending samples to Japan was changed to June 2025 and confirmed, and each participant will start the experiment using Experimental Kit at selected research sites in close contact with Japan team.
4. Problems in procedures of importing Experimental Kit and exporting soil samples were discussed, and each participant and JAEA agreed to discuss each individual case and take specific actions, such as making documents for import/export procedure, considering an alternative way of sending Experimental Kit, etc.

Session 5 and 6

The minutes of the workshop were discussed and agreed by all participants.
Mr. WADA Tomoaki, FNCA Advisor of Japan, delivered closing remarks and thanked all participants for their efforts and contribution.

October 15