An experimental approach for crown to whole-canopy defoliation in forests
An experimental approach for crown to whole-canopy defoliation in forests
复制标题
森林中树冠至整个冠层落叶的实验方法
DOI：
10.1139/cjfr-2020-0527
复制
发表时间：
2022
影响因子：
2.2
通讯作者：
Hardiman, Brady S.
中科院分区：
文献类型：
--
作者：
Fahey, Robert T.;Tanzer, Danielle N.;Alveshere, Brandon C.;Atkins, Jeff W.;Gough, Christopher M.;Hardiman, Brady S.
冠层落叶是森林生态系统中一个重要的干扰源，在大规模的操作实验中很少被代表。可缩放冠冠层水平的实验落叶是需要解开的影响，可变的强度，时间和频率对森林结构，功能和死亡率。我们提出了一种新的基于压力清洗的落叶方法，该方法可以在树冠尺度上实施，在整个树冠体积中，针对单个叶子或树木，并在数小时或数天的时间范围内完成。压力清洗被证明是成功的，在生产一致的叶水平和整个冠层落叶，叶面积指数减少10%-20%，一致的叶表面积去除跨分支机构和物种。该方法允许在森林生态系统中进行落叶干扰的林分规模实验，并具有广泛的应用潜力。利用这种标准化方法的研究，可以促进机制的了解落叶对生态系统的结构和功能的综合理解的森林类型，生态区域和落叶源的发展。
Canopy defoliation is an important source of disturbance in forest ecosystems that has rarely been represented in large-scale manipulation experiments. Scalable crown to canopy level experimental defoliation is needed to disentangle the effects of variable intensity, timing, and frequency on forest structure, function, and mortality. We present a novel pressure-washing-based defoliation method that can be implemented at the canopy-scale, throughout the canopy volume, targeted to individual leaves or trees, and completed within a timeframe of hours or days. Pressure washing proved successful at producing consistent leaf-level and whole-canopy defoliation, with 10%–20% reduction in leaf area index and consistent leaf surface area removal across branches and species. This method allows for stand-scale experimentation on defoliation disturbance in forested ecosystems and has the potential for broad application. Studies utilizing this standardized method could promote mechanistic understanding of defoliation effects on ecosystem structure and function and development of synthetic understanding across forest types, ecoregions, and defoliation sources.