Development of REDD+ safeguard for controlling extensive monocultures

2023 Fiscal Year Final Research Report

• Project/Area Number: 19H02997
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 40010:Forest science-related
• Research Institution: University of Miyazaki
• Principal Investigator: Ito Satoshi 宮崎大学, 農学部, 教授 (00231150)
• Co-Investigator(Kenkyū-buntansha): 光田 靖 宮崎大学, 農学部, 教授 (30414494) ; 平田 令子 宮崎大学, 農学部, 准教授 (50755890) ; 加治佐 剛 鹿児島大学, 農水産獣医学域農学系, 准教授 (60538247)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 熱帯林 / 生物多様性 / 大規模プランテーション / Land sparing / Land sharing

Outline of Final Research Achievements

1) Large-scale monoculture production (MP): In teak MP in East Java, Indonesia, we found that a negative core area occurs 20 m from the forest edge and seasonal variations in the forest edge effect. We clarified the relationship between stand age and plant species diversity in Cambodian rubber MP. 2) Agroforestry (AF): We verified the biodiversity conservation function and natural enemy services of AF in Indonesia. We verified the medium-term effects of creating artificial gaps in domestic secondary forests as an alternative measure during the coronavirus pandemic. 3) Satellite image analysis of Cambodia revealed that commercial forest use has increased rapidly since 2010, and by combining these findings, we simulated the occurrence of negative core areas due to large-scale MP development.

Free Research Field

造林学

Academic Significance and Societal Importance of the Research Achievements

本研究は(1)大規模MP内で生物多様性が低下する「負のコアエリア」を実データで捉えるとともに、(2)これを軽減する方策としてAFや混合栽培の生物多様性保全効果や土壌保全効果を検証した点で学術的意義が大きい。さらに、(3)過去の森林の商業的利用拡大と林縁効果の分析に基づいて負の効果が発生するプロセスをシミュレーションモデルにより予測した。これらの成果は、REDD+等の温暖化対策によって更なるMP拡大と生物多様性の低下が危惧される中、適切な森林配置によるLand Sparingと群落構造の複雑化によるLand Sharingの有用性の科学的根拠と実際的ガイドラインを示した点で社会的意義が大きい。