ブラジルのナッツの搾取の持続可能性に対する人口学的脅威
Carlos A Peres1, Claudia Baider, Pieter A Zuidema
1Centre for Ecology, Evolution and Conservation, School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK. C.Peres@uea.ac.uk
Science (New York, N.Y.)
|December 20, 2003
まとめ
ブラジルのナッツの集約的な収穫は,若い木を取り除き,アマゾンの人口を脅かしています. 管理がなければ,これらの重要なブラジルナッツ (Bertholletia excelsa) の個体群は崩壊し,地域経済に影響を及ぼします.
科学分野:
- エコロジー エコロジー エコロジー
- 保護生物学の保護生物学
- 森林管理 森林管理について
背景:
- ブラジルのナッツの木 (Bertholletia excelsa) は,アマゾンの採掘経済における鍵となる種である.
- 伐採が樹木集団の動態に与える影響を理解することは,持続可能な管理に不可欠です.
研究 の 目的:
- ブラジルのナッツの搾取の歴史と木の集団構造との関係を分析する.
- 異なる収穫の強度下でのブラジルナッツの長期生存可能性を評価する.
主な方法:
- アマゾン全域の23のブラジルナッツの集団を比較した分析.
- 幼い木 (胸高の直径60cm未満) に焦点を当てて,集団のサイズ構造の調査.
- 長期の集団動態をシミュレートするための収穫モデルの開発.
主要な成果:
- 持続的で集中的な収穫を伴う集団には若い木が不足しており,これは採用の失敗を示唆しています.
- 軽くまたは最近搾取された集団のみが,かなりの数の若木を示します.
- 収穫モデルでは,集中的に搾取されている集団を維持するために不十分な若者の採用を予測しています.
結論:
- 過去100年にわたるブラジルのナッツの集中的な搾取は持続不可能である.
- 効果的な管理介入がなければ,密集的に採集された個体群は減少し,崩壊すると予測されています.
- この経済的に重要なアマゾンの種の長期的な生存は脅かされています.
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