Non-parametric methods reveal non-linear functional trait variation of lichens along environmental and fire age gradients
Popular methods to analyse community-trait-environment relationships constrain community patterns by trait and environment relationships. What if some traits are strongly associated with community composition, but unrelated to environmental variables and vice versa? We take a different approach, unconstrained by this assumption using non-parametric methods.
We applied this technique to lichen (fungal/algal and/or cyanobacterial symbioses) communities across environmental and fire age gradients by measuring richness and cover of four important functional traits: energy generation (type of photosynthetic symbiont), water relations (inferred from growth form), dispersal capability (from vegetative propagules) and microsite specificity (measured by substrate affinity).
Nelson, P. R., B. McCune, C. A. Roland, and S. E. Stehn. 2015. Nonparametric methods reveal nonlinear functional trait variation of lichens along environmental and fire age gradients. Journal of Vegetation Science 26(5):848-865.
A lichen species list for Denali National Park and Preserve, Alaska, with comments on several new and noteworthy records
We present a substantially revised and updated lichen flora for Denali National Park and Preserve (DNPP) based on a series of field investigations conducted from 2001 to 2011. During this period, we increased the number of lichen taxa recorded in DNPP by 175 species through new collections made at 46 inventory sites and 44 vegetation monitoring study areas within the 2.4 million ha DNPP. The revised checklist we present here includes 459 taxa (in 158 genera) that occur in DNPP. We discuss the major lichen community composition patterns in this vast and previously under-studied region, and provide notes for 24 of the most noteworthy taxa discovered during our fieldwork, including geographic and ecological summaries. We identify remaining knowledge gaps and needs for future lichen inventory work in DNPP, including surveys for microlichens.
Stehn, S. E., J. K. Walton, P. R. Nelson, C. J. Hampton-Miller, and C. A. Roland. 2016. A lichen species list for Denali National Park and Preserve, Alaska, with comments on several new and noteworthy records. Evansia 32(4):195- 215.