在亚马逊森林中,大莲花日益占据主导地位
Oliver L Phillips1, Rodolfo Vásquez Martínez, Luzmila Arroyo
1Centre for Biodiversity and Conservation, School of Geography, University of Leeds LS2 9JT, UK. o.phillips@geog.leeds.ac.uk
Nature
|August 16, 2002
概括
亚马逊的老生长森林显示,柳叶树 (木质爬植物) 丰富度显著增加. 森林组成的这种变化可能会降低这些重要生态系统在未来储存碳的能力.
科学领域:
- 热带生态 热带生态
- 森林碳动态 森林碳动态
- 气候变化影响气候变化的影响.
背景情况:
- 传统上,老生长森林被认为处于动态平衡状态.
- 最近的研究表明,新热带森林正在积累碳和生物质,可能是由于大气中二氧化碳的增加.
- 改变森林社区组成对碳储存的影响尚不清楚.
研究的目的:
- 调查新热带森林中树木生物质的增加是否与社区组成的变化有关.
- 量化亚马逊老生长森林中莲花 (木质爬行植物) 丰度和主导地位的变化.
- 评估这些变化对热带陆地碳汇的影响.
主要方法:
- 从非碎片化的亚马逊森林中分析长期森林库存数据.
- 量化了两十年来树密度,基底面积和平均尺寸的变化.
- 与树木相比,树占主导地位的相对增加的评估.
主要成果:
- 在亚马逊老生长森林中,观察到香的密度,基底面积和平均尺寸的持续增加.
- 在20世纪后期,大型树相对于树木的占主导地位每年增加1.7-4.6%.
- 发现柳叶会增加树木的死亡率并抑制树木的生长.
结论:
- 林数量的快速增加意味着亚马逊老生长森林的社区组成发生了重大变化.
- 这种组成变化对热带陆地碳汇的未来有着重大影响.
- 目前预测热带碳流的模型需要纳入假定不受干扰的森林中发生的动态变化.
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