reference document

[1]IUCN https://www.iucn.org/our-work/nature-based-solutions

[2]Consideration of Nature-based Solutions as Offsets in Corporate Climate Change Mitigation Strategies (Seymour and Langer 2021)

[3]https://www.meti.go.jp/shingikai/energy_environment/carbon_credit/pdf/004_s04_00.pdf