世界の生物多様性:最近の減少の指標
Stuart H M Butchart1, Matt Walpole, Ben Collen
1United Nations Environment Programme World Conservation Monitoring Centre, 219 Huntingdon Road, Cambridge CB3 0DL, UK. stuart.butchart@birdlife.org
Science (New York, N.Y.)
|May 1, 2010
まとめ
世界各国首脳は,2010年までに生物多様性の損失を削減することを目指した. しかし,いくつかの保全の努力にもかかわらず,種の個体数,生息地,生態系は減少し続け,生物多様性喪失のペースが減速していないことを示しています.
科学分野:
- エコロジー エコロジー エコロジー
- 環境科学 環境科学
- 保護生物学の保護生物学
背景:
- 世界の指導者は,生物多様性に関する条約の下で,2010年までに生物多様性の損失を削減することを約束しました.
- 生物多様性は,生態系の安定と人間の福祉にとって極めて重要です.
- 生物多様性の傾向を監視することは,効果的な保全戦略にとって不可欠です.
研究 の 目的:
- 2010年の生物多様性目標に向けた進展を,包括的な一連の指標を用いて評価する.
- 生物多様性の状態と生物多様性に及ぼす圧力の両面の動向を評価する.
- 生物多様性の喪失率が著しく減少したかどうかを判断する.
主な方法:
- 生物多様性の状態,圧力,社会的反応をカバーする31の指標をまとめ,分析した.
- 人口動向の評価,絶滅の危険,生息地の範囲と状態,コミュニティの構成.
- 資源消費,侵入種,汚染,過剰搾取,気候変動などの圧力の評価.
主要な成果:
- 生物多様性状態のほとんどの指標 (種集団,絶滅リスク,生息地) は,継続的な減少を示した.
- 生物多様性への圧力 (資源利用,侵入種,汚染) の指標は,一般的に増加した.
- 保護への対応において,いくつかの局所的な成功にもかかわらず,生物多様性の損失の全体的な割合は減速していません.
結論:
- 生物多様性の減少を減らすという2010年の目標は達成されなかった.
- 継続的かつ潜在的に強まる圧力により,生物多様性が世界中で減少しています.
- ネガティブな傾向を逆転させるために,強化され,より効果的な保全行動が緊急に必要とされています.
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