Data from: Spectral diversity area relationships for assessing biodiversity in a wildland-agriculture matrix

Species-area relationships have long been used to assess patterns of species diversity across scales. Here this concept is extended to spectral diversity using hyperspectral data collected by NASA's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) over western Michigan. This mixture of mesic forest and agricultural lands offers two end-points on the local-scale diversity continuum – one set of well mixed forest patches and one set of highly homogeneous agricultural patches. Using the sum of the first three principal component values and the principal components’ convex hull volume, spectral diversity was compared within and among these plots and to null expectations for perfectly random and perfectly patchy landscapes. Overall the spectral diversity area relationship confirms the patterns that would be expected for this landscape, but this application suggests that this approach could be extended to less well understood landscapes and could reveal key insights about the relative importance of different drivers of community assembly, even in the absence of additional data about plant functional traits or species’ identities.物种-面积关系（species-area relationships）长期以来被用于评估不同尺度下的物种多样性格局。本研究将该概念拓展至光谱多样性领域，所用高光谱数据（hyperspectral data）由美国国家航空航天局（NASA）的机载可见/红外成像光谱仪（Airborne Visible/Infrared Imaging Spectrometer，缩写AVIRIS）在密歇根州西部上空采集。该区域由中生林（mesic forest）与农田混合而成，在局域尺度的多样性连续体上提供了两个典型端点：一组为混合均匀的林斑，另一组为高度均质的农田斑块。研究通过前三个主成分（principal component）值之和与主成分凸包体积，对各斑块样地内部、样地间的光谱多样性进行了对比，并与完全随机景观和完全斑块化景观的零假设期望进行了比对。总体而言，光谱多样性-面积关系验证了该景观的预期格局，但本研究的应用表明，该方法可推广至认知程度相对不足的景观，且即便未获取植物功能性状（plant functional traits）或物种鉴定的额外数据，也能揭示群落构建（community assembly）不同驱动因子相对重要性的关键科学见解。