Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA.
Department of Forest Resources, University of Minnesota, St Paul, MN, USA.
Nat Ecol Evol. 2021 Jan;5(1):46-54. doi: 10.1038/s41559-020-01329-4. Epub 2020 Nov 2.
Quantifying how biodiversity affects ecosystem functions through time over large spatial extents is needed for meeting global biodiversity goals yet is infeasible with field-based approaches alone. Imaging spectroscopy is a tool with potential to help address this challenge. Here, we demonstrate a spectral approach to assess biodiversity effects in young forests that provides insight into its underlying drivers. Using airborne imaging of a tree-diversity experiment, spectral differences among stands enabled us to quantify net biodiversity effects on stem biomass and canopy nitrogen. By subsequently partitioning these effects, we reveal how distinct processes contribute to diversity-induced differences in stand-level spectra, chemistry and biomass. Across stands, biomass overyielding was best explained by species with greater leaf nitrogen dominating upper canopies in mixtures, rather than intraspecific shifts in canopy structure or chemistry. Remote imaging spectroscopy may help to detect the form and drivers of biodiversity-ecosystem function relationships across space and time, advancing the capacity to monitor and manage Earth's ecosystems.
量化生物多样性如何通过时间在大空间范围内影响生态系统功能，是实现全球生物多样性目标所必需的，但仅通过基于实地的方法是不可行的。成像光谱学是一种有潜力帮助应对这一挑战的工具。在这里，我们展示了一种评估幼林生物多样性影响的光谱方法，该方法提供了对其潜在驱动因素的深入了解。利用树木多样性实验的机载成像，我们能够量化林分之间的光谱差异，从而量化对茎生物量和冠层氮的净生物多样性效应。通过随后对这些效应进行划分，我们揭示了不同的过程如何导致林分水平光谱、化学和生物量的多样性诱导差异。在林分内，生物量超产最好由具有更大叶片氮的物种来解释，这些物种在混合物中主导上层树冠，而不是冠层结构或化学的种内变化。远程成像光谱学可能有助于检测生物多样性-生态系统功能关系的形式和驱动因素，从而提高监测和管理地球生态系统的能力。
