lichens on extensive green roofs : Cladonia evapotranspiration , substrate temperature , and albedo

Green roofs are constructed ecosystems that provide ecosystem services in urban environments. Shallow substrate green roofs subject the vegetation layer to desiccation and other environmental extremes, so researchers have evaluated a variety of stress-tolerant vegetation types for green roof applications. Lichens can be found in most terrestrial habitats. They are able to survive extremely harsh conditions, including frequent cycles of desiccation and rehydration, nutrient-poor soil, fluctuating temperatures, and high UV intensities. Extensive green roofs (substrate depth <20cm) exhibit these harsh conditions, making lichens possible candidates for incorporation into the vegetation layer on extensive green roofs. In a modular green roof system, we tested the effect of lichens on substrate temperature, water loss, and Cladonia albedo compared to a substrate-only control. Overall, the modules Cladonia had significantly cooler substrate temperatures during the summer and significantly warmer temperatures during the fall. Additionally, the Cladonia modules lost significantly less water than the substrate-only control. This implies that they may be able to benefit neighboring vascular plant species by reducing water loss and maintaining favorable substrate temperatures. Amy Heim ( ) Corresponding author: [email protected] Heim A and Lundholm J. How to cite this article: lichens on extensive green roofs: evapotranspiration, substrate temperature, Cladonia 2014, :274 (doi: ) and albedo [version 2; referees: 2 approved] F1000Research 2 10.12688/f1000research.2-274.v2 © 2014 Heim A and Lundholm J. This is an open access article distributed under the terms of the Copyright: Creative Commons Attribution , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Data associated Licence with the article are available under the terms of the (CC0 1.0 Public domain dedication). Creative Commons Zero "No rights reserved" data waiver This research was funded by NSERC Discovery Grant 311788-2010 to J. Lundholm. Grant information: The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: No competing interests were disclosed. 16 Dec 2013, :274 (doi: ) First published: 2 10.12688/f1000research.2-274.v1 Referee Status: