Effects of New Forestry Practices on Rare Epiphytic Macrolichens

Abstract

The preservation of key habitats is included in modern forest-management practices as one of the main means to preserve biodiversity in northern European production forests. I examined the distribution patterns and persistence of occurrence of rare epiphytic macrolichens in a predominantly unprotected forest landscape with an area of 278 km 2 in southern Finland. Occurrence data of macrolichens in two key habitats, rock outcrops and mires, were compared with data from production forests. The density of populations of rare macrolichens was 50-fold higher on rock outcrops and 25-fold higher on mires than in production forests. Most rare species of epiphytic macrolichens were found only in key habitats. In modern, intensively managed forest landscapes, rock outcrops appeared to represent the main habitats for rare macrolichens as a result of the long-term continuity of old trees. Most macrolichen occurrences represented very small populations with a high extinction risk. Of the populations found in 1989-1995 in key habitats, 51% had disappeared, by 2000-2001, mainly as a result of forestry activities. The disappearance of populations significantly exceeded the rate of establishment of new populations. My results emphasize the importance of key habitats for declining forest species. There is also a need to improve and sharpen the guidelines for delimiting and managing key habitats in order to halt the continued decline of epiphytic macrolichens.Resumen: La preservación de hábitats clave esta incluida en prácticas de gestión forestal modernas como uno de los muchos medios para preservar la biodiversidad de bosques de producción en el norte de Europa. Examiné los patrones de distribución y la persistencia de ocurrencia de macrolíquenes epifíticos raros en un paisaje de bosque predominantemente no protegido con una extensión de 278 km 2 en el sur de Finlandia. Comparé datos de ocurrencia de macrolíquenes en dos hábitats clave, afloramientos rocosos y ciénegas, con datos de bosques de producción. La densidad de poblaciones de macrolíquenes raros fue 50 veces mayor en afloramientos y 25 veces mayor en ciénegas que en bosques de producción. La mayoría de las especies de macrolíquenes epifíticos raros fueron encontradas solo en hábitats claves. En el paisaje de bosque bajo manejo intensivo, los afloramientos representaron los hábitats principales para macrolíquenes raros debido a la continuidad a largo plazo deárboles viejos. La mayoría de las ocurrencias de macrolíquenes representaron poblaciones muy pequeñas con un alto riesgo de extinción. Cincuenta y un porciento de las poblaciones encontradas en 1989-1995 en hábitats clave habían desaparecido en 2000-2001, debido a actividades forestales principalmente. La desaparición de poblaciones excedió significativamente la tasa de establecimiento de poblaciones nuevas. Mis resultados destacan la importancia de hábitats clave para especies forestales en declinación. También existe la necesidad de mejorar y afinar los lineamientos para delimitar y manejar los hábitats clave para...

Predicting the potential spatial distributions of epiphytic lichen species at the landscape scale

“…Epiphytic lichens are well known to be sensitive to host tree species and forest structure and management (Barkman 1958;Dietrich & Scheidegger 1996;Uliczka & Angelstam 1999;Ihlen et al 2001;Johansson & Ehrlén 2003;Pykälä 2004). Although the forest types used here characterized very crudely the habitat requirements of the lichen species examined, for four out of the six species the forest types were important for modelling the species distributions.…”

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

“…In spite of the many localities of Lobaria pulmonaria in Fennoscandia and the Baltic region (Andersson et al, 2003;Pykälä, 2004;Jüriado & Liira, 2009), the species is still threatened on the European level. In Estonia, L. pulmonaria is threatened because it prefers over-mature and old stands, and particularly stands of rare types (e.g.…”

“…For example, 51% of the macrolichen populations (including L. pulmonaria) in Finnish key habitats found in the years 1989-1995 had disappeared by 2000 or 2001, mainly due to forestry activities (Pykälä, 2004). It is suggested that even if the remain-ing old-growth sites are left uncut, the populations of L. pulmonaria likely decline, and the species is subjected to an extinction debt, driven by decreased amount and connectivity of suitable habitat over the last 150 years (Öckinger & Nilsson, 2010).…”

“…In contrast to its overall European status, L. pulmonaria is still frequent in Fennoscandia and in the Baltic region. Here the lichen has mainly been recorded in small and fragmented old forest patches in managed forests (Auzinš & Ek, 2001;Gu et al, 2001;Andersson et al, 2003;Pykälä, 2004;Jüriado & Liira, 2009), and it prefers large-diameter host trees (Riiali et al, 2001;Öckinger et al, 2005;Gu et al, 2001;Mikhailova et al, 2005;Edman et al, 2008;Belinchon et al, 2009). In highly humid conditions, L. pulmonaria also occurs on younger trees and on rocks (Hakulinen, 1964;James et al, 1977;Carlsson & Nilsson, 2009).…”

“…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).…”