Assessment of Enhanced Climate Change Resilience through Carbon Sequestration in Tropical Soils

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K20585
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0602:Agricultural and environmental biology and related fields
• Research Institution: Japan International Research Center for Agricultural Sciences
• Principal Investigator: Shinya Iwasaki 国立研究開発法人国際農林水産業研究センター, 農村開発領域, 任期付研究員 (40915261)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: 土壌炭素 / 畑土壌肥沃度 / 気候変動レジリエンス / キャッサバ

Outline of Final Research Achievements

The objective of this study was to understand soil physico-chemical changes through comprehensive soil analysis and to evaluate the improvement of climate change resilience through carbon sequestration in a long-term continuous use study over 45 years in Thailand. Differences in soil physical properties, such as soil structure and the vertical distribution of soil carbon, were identified among the different management practices. Structural equation modeling was used to visualize the interactions among the effects of different management practices on soil carbon sequestration, soil physicochemical properties, and crop yield. It was found that water and nutrient retention functions derived from soil organic matter were more dominant in sandy soils than in clay soils and that crop yield was relatively enhanced by soil carbon sequestration. The results were reported at domestic and international conferences and submitted as an original paper.

Free Research Field

土壌学

Academic Significance and Societal Importance of the Research Achievements

国際的に炭素排出量の低減がうたわれるなか、土壌炭素貯留への期待も高まっている。しかしながら高温多湿環境により、土壌有機物分解が卓越する湿潤熱帯地域において、温帯や亜寒帯を中心に進んできた炭素動態メカニズムをそのまま適用することはできない。熱帯では最大規模の長期連用試験をもとに炭素貯留量の算定と作物生産への影響を示した本研究の意義は大きい。また、土壌型によって、有機物施用による土壌炭素貯留速度および土壌炭素が肥沃度向上に与える影響が異なることが明らかになったことは、土壌炭素動態モデルの構築に大きく寄与する。