劣化した熱帯雨林を保護区に追加するための値
Robert M Ewers1, C David L Orme2, William D Pearse2
1Georgina Mace Centre for the Living Planet, Department of Life Sciences, Imperial College London, Ascot, UK. r.ewers@imperial.ac.uk.
Nature
|July 17, 2024
まとめ
伐採された森林は 重要なバイオマスを除去した森林であっても 生物多様性の価値が保たれています 伐採量が少ない森林 (バイオマスの除去量は29%未満) は,特に保全のために重要であり,自然に回復することができます.
科学分野:
- エコロジー
- 保護生物学
- 林業
背景:
- 伐採された森林は 劣化した生態系として見なされます
- しかし,これらのダイナミックな環境は,重要な生物多様性を持ち,保全価値を持っています.
- 採伐された森林の価値は しばしば過小評価されています
研究 の 目的:
- 伐採された森林の保全価値を評価するための経験的値を定義する.
- 伐採の強度が種の発生と機能的組成に与える影響を分析する.
- 熱帯雨林の保全戦略にデータに基づく洞察を提供すること.
主な方法:
- マレーシアのサバ州で86の階層と126の機能群で1681の分類を分析した.
- 伐採の強度とバイオマスの除去に関連した個々の発生パターンの評価
- 森林の劣化に関する保全に係る限界値の特定
主要な成果:
- 軽く伐採された森林 (バイオマスの除去量<29%) は,高い保全価値と大部分の機能的組成を維持しています.
- 生物多様性に対する最も極端な影響は,高度に劣化した森林 (>68%のバイオマス除去) にあります.
- バイオマスの除去を基に2つの異なる保全の値が特定されました.
結論:
- 伐採された森林は 相当な保全価値を持ち,保全活動において 見過ごすべきではありません.
- 軽く伐採された森林は,自然再生と伐採前の生物多様性の回復に高い可能性を秘めています.
- 深刻な森林破壊は 生物多様性の価値を回復するために 集中的で費用のかかる 介入を必要とします
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