Lobaria pulmonaria abundance as an indicator of macrolichen diversity in Interior Cedar–Hemlock forests of east-central British Columbia

Abstract

Orographic precipitation over interior mountains has resulted in the formation of the inland temperate rainforest, where certain stands are potentially antique and support a rich flora of epiphytic macrolichens. We documented macrolichen diversity across three age-classes in forests of the Interior Cedar-Hemlock biogeoclimatic zone (i.e., ICHwk3 subzone) east of Prince George, British Columbia. Our objectives were to report changes in lichen communities with stand age, identify potential indicators of antiquity, and investigate the functional role of dominant species in the ecosystem. We identified 41 taxa, including 4 alectorioid lichens, 21 foliose chlorolichens, and 16 old-growthassociated chlorolichens and cyanolichens. Older forests supported more species than young or mature forests. The abundance of Lobaria pulmonaria (L.) Hoffm. was strongly correlated with this increase in diversity and may therefore be an appropriate indicator of stand age in the ICH. The increase in L. pulmonaria and other N 2 -fixing cyanolichens with stand age may have significant implications for forest nitrogen budgets in the interior of British Columbia, where atmospheric nitrogen deposition is relatively low and biological N 2 fixation accounts for nearly all of the nitrogen lost to forest harvesting. We hope that this greater understanding of lichen ecology across age-classes will promote sustainable stewardship of the remaining old-growth forests of inland British Columbia.Résumé : La précipitation orographique sur les montagnes de l'intérieur a conduit à la forêt ombrophile continentale, où certains peuplements sont potentiellement anciens et supportent une riche flore de macrolichens épiphytes. Les auteurs ont étudié la diversité des macrolichens, selon trois classes d'âge, dans ces forêts continentales à cèdre et pruche (c.-à-d., zone biogéoclimatique ICHwk3), à l'est de Prince George, en Colombie-Brittanique. Les objectifs étaient de faire état des changements survenant dans les communautés de lichens selon l'âge du peuplement, d'identifier des indicateurs potentiels d'ancienneté et d'étudier le rôle fonctionnel des espèces dominantes dans l'écosystème. On a ainsi identifié 41 taxons, incluant 4 lichens alectoriaux, 21 chlorolichens foliacés et 16 chlorolichens et cyanolichens associés aux vieilles forêts. Les forêts plus vieilles supportent plus d'espèces que les forêts jeunes ou matures. L'abondance du Lobaria pulmonaria (L.) Hoffm. montre une forte corrélation avec l'augmentation de la diversité et pourrait consé-quemment constituer un bon indicateur de l'âge des peuplements d'ICH. L'augmentation du L. pulmonaria et autres cyanolichens fixateurs de l'azote, selon l'âge du peuplement, pourrait avoir des implications significatives quant au budget de l'azote en Colombie-Brittanique continentale, où la déposition atmosphérique de l'azote est relativement faible et où la fixation biologique de l'azote constitue presque la moitié de tout l'azote perdu par la récolte forestière. Les auteurs souhaitent que cette compréhension a...

Evaluation of the environmental quality of a protected riparian forest in Southern Brazil

“…Species from this genus have been cited as indicators of preserved forest ecosystems and associated with forest areas of high ecological continuity (Campbell andFredeen 2004, Liira andSepp 2009). Their presence is also associated with a variety of other rare or endangered species, and hence they can be considered as umbrella species (Scheidegger andWerth 2009, Nascimbene et al 2010).…”

Threatened forest lichen Lobaria pulmonaria - its past, present and future in Estonia

“…It has been widely used as an indicator species of undisturbed forest ecosystems and forest areas of long ecological continuity (Rose, 1976;Andersson & Appelqvist, 1987;Andersson et al, 2003;Liira & Sepp, 2009). Furthermore, as L. pulmonaria associates with many other rare or endangered lichen species (Campbell & Fredeen, 2004;Pykälä, 2004;Nascimbene et al, 2010) and wood beetles (Nilsson et al, 1995) of old growth forests, it has been used as a flagship or umbrella species for nature conservation (Scheidegger & Werth, 2009).…”

Canopy macrolichen distribution in a very wet oldgrowth forest landscape of the upper Fraser River watershed.

“…First, the presence and high abundance of L. pulmonaria across most of our research sites (wet or dry) proved not to be a sensitive indicator to site-specific conditions and lichen diversity (as suggested by Campbell and Fredeen (2004)). This result concurs with Kalwij et al (2005) that suggested that L.pulmonaria at the site level is not sensitive to landscape disturbances, but could be a useful indicator of lichen diversity and disturbance frequencies when comparing among regional landscapes.…”

“…Goward and Arsenault (2000) identify some of these forest stands as "antique": sites where the last major stand replacement disturbance event, such as fire, happened well before the current generation of trees established. Preliminary studies (Goward 2003) In the U.S. Pacific Northwest and elsewhere canopy macrolichens have been used as indicators of stand age (Hyvarinen et al 1992, Campbell andFredeen 2004) and environmental conditions on forested landscapes (McCune et.al. 2000, 2002, Liden and Hilmo 2005.…”