Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA.
Ecol Lett. 2012 Dec;15(12):1406-14. doi: 10.1111/j.1461-0248.2012.01864.x. Epub 2012 Sep 20.
Tropical forest structural variation across heterogeneous landscapes may control above-ground carbon dynamics. We tested the hypothesis that canopy structure (leaf area and light availability) - remotely estimated from LiDAR - control variation in above-ground coarse wood production (biomass growth). Using a statistical model, these factors predicted biomass growth across tree size classes in forest near Manaus, Brazil. The same statistical model, with no parameterisation change but driven by different observed canopy structure, predicted the higher productivity of a site 500 km east. Gap fraction and a metric of vegetation vertical extent and evenness also predicted biomass gains and losses for one-hectare plots. Despite significant site differences in canopy structure and carbon dynamics, the relation between biomass growth and light fell on a unifying curve. This supported our hypothesis, suggesting that knowledge of canopy structure can explain variation in biomass growth over tropical landscapes and improve understanding of ecosystem function.
热带雨林结构在异质景观中的变化可能会控制地上碳动态。我们检验了这样一个假设，即通过激光雷达远程估算的冠层结构（叶面积和光照可用性）控制着地上粗木质生产（生物量增长）的变化。在巴西马瑙斯附近的森林中，利用一个统计模型，这些因素预测了不同树木大小类别的生物量增长。同一统计模型，没有参数化变化，但由不同的观测到的冠层结构驱动，预测了 500 公里以东的一个地点的更高生产力。空隙分数和植被垂直程度和均匀性的度量也预测了一公顷地块的生物量增益和损失。尽管在冠层结构和碳动态方面存在显著的地点差异，但生物量增长与光之间的关系符合统一的曲线。这支持了我们的假设，即冠层结构的知识可以解释热带景观中生物量增长的变化，并提高对生态系统功能的理解。
