Persistent effects of fragmentation on tropical rainforest canopy structure after 20 years of isolation.
Persistent effects of fragmentation on tropical rainforest canopy structure after 20 years of isolation.
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隔离 20 年后，破碎化对热带雨林冠层结构的持续影响。
DOI：
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发表时间：
2019
影响因子：
5
通讯作者：
P. Brancalion
中科院分区：
文献类型：
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作者：
D. R. Almeida;S. Stark;J. Schietti;J. Camargo;N. Amazonas;E. Gorgens;D. M. Rosa;Marielle N. Smith;Ruben Valbuena;Ruben Valbuena;S. Saleska;A. Andrade;Rita Mesquita;S. Laurance;W. Laurance;T. Lovejoy;E. Broadbent;Y. Shimabukuro;Geoffrey G. Parker;M. Lefsky;C. A. Silva;P. Brancalion
评估破碎化对热带森林地上结构的持续影响，对于了解土地利用变化对碳储存和其他生态系统功能的影响至关重要。我们调查了林冠结构，地上木质生物量（AGB），AGB营业额的边缘距离和片段大小的影响，在巴西亚马逊河中部的森林片段项目（BDFFP）的生物动力学，经过22年以上的片段隔离，通过结合冠层变量收集便携式冠层轮廓激光雷达和机载激光扫描调查与长期的森林清查。森林高度下降了30%，在边缘的大片段（> 10公顷）和内部的小片段（< 3公顷）。在较大的碎片，树冠高度减少到40米的边缘。叶面积密度分布不同的边缘附近：林下植被的密度较高，中层植被较低，一致的冠层重组，通过增加再生的先驱后碎片化死亡的大树。然而，冠层开放度和叶面积指数保持相似的控制地块在整个片段，而冠层空间异质性一般较低的边缘。AGB储量和通量与冠层高度呈正相关，与空间异质性呈负相关。其他森林结构变量通常用于评估破碎化的生态影响（断面积，密度的个人，和先锋树的密度）也与激光雷达衍生的冠层表面变量。冠层重组，通过更换边缘敏感的物种的干扰容忍的可能减轻了生物量损失的影响，由于在早年的BDFFP观察到的碎片。激光雷达技术提供了新的见解和观测尺度，用于分析破碎化对森林结构和功能的生态影响，特别是地上生物量储存。本文受版权保护。All rights reserved.
Assessing the persistent impacts of fragmentation on above ground structure of tropical forests is essential to understanding the consequences of land use change for carbon storage and other ecosystem functions. We investigated the influence of edge distance and fragment size on canopy structure, aboveground woody biomass (AGB), and AGB turnover in the Biological Dynamics of Forest Fragments Project (BDFFP) in central Amazon, Brazil, after 22+ years of fragment isolation, by combining canopy variables collected with Portable Canopy profiling lidar and airborne laser scanning surveys with long-term forest inventories. Forest height decreased by 30% at edges of large fragments (> 10 ha) and interiors of small fragments (< 3 ha). In larger fragments, canopy height was reduced up to 40 m from edges. Leaf area density profiles differed near edges: the density of understory vegetation was higher and midstory vegetation lower, consistent with canopy reorganization via increased regeneration of pioneers following post-fragmentation mortality of large trees. However, canopy openness and leaf area index remained similar to control plots throughout fragments, while canopy spatial heterogeneity was generally lower at edges. AGB stocks and fluxes were positively related to canopy height and negatively related to spatial heterogeneity. Other forest structure variables typically used to assess the ecological impacts of fragmentation (basal area, density of individuals, and density of pioneer trees) were also related to lidar-derived canopy surface variables. Canopy reorganization through the replacement of edge-sensitive species by disturbance-tolerant ones may have mitigated the biomass loss effects due to fragmentation observed in the earlier years of BDFFP. Lidar technology offered novel insights and observational scales for analysis of the ecological impacts of fragmentation on forest structure and function, specifically aboveground biomass storage. This article is protected by copyright. All rights reserved.