Edge effects on epiphytic communities in a Mediterranean Quercus pyrenaica forest
Abstract:Question: What are the edge effect responses of epiphytic lichen communities in Mediterranean Quercus pyrenaica forest?
Location: Central Spain.
Methods: We established ten transects perpendicular to a road dissecting a well conserved remnant of Q. pyrenaica forest into two sections. Transects extended from the forest/road edge to 100 m into the forest. Data were collected from seven plots in each transect at different distances from the edge. Variables were grouped into stand scale variables (distance to edge, number of trees per plot, mean diameter per plot, irradiance) and tree scale variables (diameter and height of sampled trees, aspect of the sampled square and relative height of the square). We used General Mixed Linear Models and constrained ordination techniques to test the hypothesis that the spatio-temporal heterogeneity of light and water controls the occurrence of lichens and bryophytes along the edge-interior gradient in the Q. pyrenaica forest.
Results: Microclimatic parameters vary in a non-linear way; edge and interior stands showed the most divergent and extreme values. Although the micro-environment within Mediterranean forests is heterogeneous, interior conditions are apparently suitable for the performance of some specific forest epiphytes. Consequently, species richness does not show significant differences along the gradient. Total epiphytic cover increases towards the forest interior, but distance to the edge together with other predictors at the tree scale (aspect and height of the square) are the most relevant predictors for the composition and structure of these communities.
Conclusions:Composition and structure of epiphytic communities in a Mediterranean semi-deciduous forest are affected by the edge between the forest and the road constructed. Since some extremely rare lichens only occur at interior stands, the conservation of these threatened elements requires urgent conservation measures because well preserved and unmanaged forests in the Mediterranean region are very rare.
Document Type: Research Article
Publication date: February 1, 2007
More about this publication?
- The Journal of Vegetation Science publishes original articles, short notes and review articles in the field of vegetation science, both methodological and theoretical studies, and descriptive and experimental studies of plant communities and plant populations. The Journal is the Official Organ of the International Association for Vegetation Science (IAVS).
- Editorial Board
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Terms & Conditions
- ingentaconnect is not responsible for the content or availability of external websites