Contents lists available at ScienceDirect Forest Ecology and Management journal homepage: www.elsevier.com/locate/foreco Looking for a home: Exploring the potential of epiphytic lichens to colonize tree plantations in a Macaronesian laurel forest Cristina González-Montelongo, Israel Pérez-Vargas ⁎ Department of Botany, Ecology and Plant Physiology, Universidad de La Laguna, San Cristóbal de La Laguna, Apdo. Postal 456, CP: 38200 Santa Cruz de Tenerife, Canary Islands, Spain ARTICLEINFO Keywords: Canary Islands Exotic plantations Laurel forest Lichen diversity Macaronesia ABSTRACT Mankind has been altering native forests in Macaronesia for at least five centuries. Forestry practices are known to reduce biodiversity due to habitat loss, fragmentation and alteration. To assess the potential of plantations to provide habitat for epiphytic lichens in comparison with native forests, we examined three types of forest in the Canary Islands: laurel forest (native forest) and two monospecific plantations of Pinus radiata and Eucalyptus globulus. Epiphytic lichen diversity was evaluated using a methodology of species richness and lichen diversity values (LDV). Our results demonstrate that the conversion of laurel forests to monoculture plantations of exotic tree species decreases lichen diversity and alters lichen community composition. Our findings hightlight how nativeepiphyticlichensfromthecloudforestcannotsurviveunderthesameclimaticconditionsifthehostplant community is changed. 1. Introduction According to the Food and Agriculture Organization of the United Nations (FAO), forests constitute the biggest world reserve of biodi- versity. However, natural forests are disappearing from a large part of their potential distribution while tree plantations are expanding pri- marily for wood biomass production, but also for soil and water con- servation or wind protection (Carnus et al., 2006; FAO, 2018). This trend is already recognized as a serious threat to biodiversity and fur- ther intensification might worsen the situation (Strengbom et al., 2011; Bäcklund et al., 2016). The Canary Islands belong to Macaronesia, a globally recognized area for biodiversity, including in the mediterrean basin, one of the 35 World Biodiversity Hotspots (Conservation International, 2019). This phytogeographical region is comprised of five Atlantic volcanic archi- pelagos (the Azores, Madeira, the Selvagens, the Canaries and the Cape Verde) as well as the Macaronesian Enclave (Báez and Sánchez-Pinto, 1983; Jaén-Molina et al., 2009) on the African mainland. The area is characterized by high biodiversity and a vast array of organisms which are endemic to the region (Juan et al., 2000). The Canaries play a key role within the region (Médail & Quézel, 1999); particularly lichens which contribute significantly to its biodiversity with more than 1600 species listed in this archipelago (Hernández-Padrón & Pérez-Vargas, 2010). One of the most remarkable features of this area is the existence of an endemic forest, a remnants of Pliocene/Pleistocene forests in Macaronesia that likely underwent changes in their distribution areas during the Pleistocene temperature oscillations (Kondraskov et al., 2015). The composition of tree species is a primary attribute of forest ecosystems and this is often manipulated by silvicultural practices. The transformation of forests in the Canary Islands started with the abori- ginal inhabitants; they did not have sophisticated tools but the forests were changed through fire and the introduction of sheep, goats and others farm animals, as well as other plants (Fernández-Palacios & Whittaker, 2008; del Arco et al., 2010). After the Hispanic colonization in the 15th century, the natural landscape became increasingly trans- formed. In the second half of the twentieth century, a significant amountofthisnativelaurelforestwasclearedintheCanariesforcattle breeding,agricultureandforplantingexoticspecies,primarilypineand gum, the most common genera used in plantations worldwide (Carnus et al., 2006). Plantations were established for a variety of reasons in- cluding wood production, building supplies, draining areas as a form of pest control and also to create rural employment. The laurel forest, a priority habitat included on Annex I of the Habitats Directive, is an importantMacaronesianecosystemduetoitshighendemicbiodiversity (Fernández-Palacios and Martín-Esquivel, 2001). However, it has re- treated greatly over time and now only covers less than 12% of the potential distribution area in the archipelago (del Arco et al., 2010). Epiphytes comprise a highly diverse group of organisms which are https://doi.org/10.1016/j.foreco.2019.117541 Received 28 June 2019; Received in revised form 6 August 2019; Accepted 11 August 2019 ⁎ Corresponding author. E-mail addresses: cgonzalm@ull.es (C. González-Montelongo), ispeva@ull.es (I. Pérez-Vargas). Forest Ecology and Management 453 (2019) 117541 0378-1127/ © 2019 Elsevier B.V. All rights reserved. T