まとめ
ブラジルのアマゾンの森林伐採は,1978年から1988年の間に大幅に増加した. この熱帯森林の伐採と森林の断片化は,生物多様性に深刻な影響を及ぼし,以前見積もられていたよりも大きな影響を及ぼしました.
科学分野:
- 環境科学 環境科学
- エコロジー エコロジー エコロジー
- リモートセンシング (リモートセンサー)
背景:
- ブラジルのアマゾン盆地には,膨大な生物多様性が保たれています.
- 森林伐採のパターンを理解することは,保全活動において極めて重要です.
研究 の 目的:
- 1978年から1988年の間,ブラジルのアマゾンの森林伐採と森林の断片化とその影響,および辺縁効果を定量化するために.
- これらの変化が生物多様性に及ぼす影響を評価する.
主な方法:
- ブラジルのアマゾンの森林地帯を包括的にカバーするために,Landsatの衛星画像を使用しました.
- 森林伐採,森林の断片化 (森林伐採に囲まれた面積は100平方キロメートル未満),および辺縁効果 (森林伐採から森林に1km入り) を測定した.
主要な成果:
- 熱帯森林伐採は1978年の7万8千平方キロメートルから1988年の23万平方キロメートルに拡大した.
- 熱帯雨林の生息地が深刻な影響を受け,生物多様性に影響を及ぼし,20万8000平方キロメートルから58万8000平方キロメートルに増加した.
- 森林伐採の割合は,以前の推定値より低いものの,生物多様性にはより大きな影響を与えた.
結論:
- ブラジルのアマゾンの森林伐採は,大きく加速している問題です.
- 森林の断片化と縁の効果は,生物多様性の損失を悪化させる.
- 保護戦略は,森林伐採が生物多様性に与える影響の拡大を考慮しなければならない.
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