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在全球范围内绘制树木密度图

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
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此摘要是机器生成的。

全球森林树木数量约为3.04万亿, 自人类文明开始以来, 森林砍伐导致树木数量下降了46%.

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科学领域:

  • 生态学
  • 森林管理
  • 环境科学

背景情况:

  • 了解森林树木的分布对于全球生物圈研究至关重要.
  • 之前的估计全球树木数量显著下降.

研究的目的:

  • 创建森林树密度的第一个空间连续全球地图.
  • 提供全球树木总数的最新估计.

主要方法:

  • 使用地面数据和空间建模的组合.
  • 气候,地形和人类影响的综合数据.

主要成果:

  • 估计全球树木数量约为3.04万亿.
  • 已确定热带和亚热带森林树木密度最高 (1.39万亿).
  • 发现人类活动使全球树木数量自文明开始以来大幅减少了46%.

结论:

  • 气候和地形影响当地树木密度.
  • 人类影响是影响全球树木密度的主要因素.
  • 估计每年有15亿棵树因为森林砍伐而消失.