世界規模で木の密度をマッピングする
T W Crowther1, H B Glick1, K R Covey1
1Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
Nature
|September 3, 2015
まとめ
世界の森林樹木数は 約3.04兆で 予想よりかなり高いのです 森林伐採により 人類文明が始まって以来 木の数は46%減少しました
科学分野:
- エコロジー
- 林業
- 環境科学
背景:
- 森林の樹木の分布を理解することは,地球生物圏の研究にとって極めて重要です.
- 過去の推定では 樹木の数はかなり低かった.
研究 の 目的:
- 森林の樹密度に関する 世界初の空間的に連続した地図を作成します
- 世界の樹木の総数を 最新の見積もりで提供するためです
主な方法:
- グラウンドデータと空間モデルの組み合わせを用いた.
- 気候,地形,人間の影響に関する統合データ
主要な成果:
- 約3兆4千億の樹木が 植えられています
- 樹木密度が最も高いのは熱帯および亜熱帯の森林である (1.39兆).
- 文明が始まって以来 地球上の木の数は 46%減少しました
結論:
- 気候と地形は地元の木の密度に影響します.
- 人間による影響が 樹木密度に影響を及ぼす 主要な要因です
- 森林伐採により毎年15億本の木が 失われていると推定されています
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