Predictability of plant and fungal species richness of old‐growth boreal forest islands

Abstract

Abstract. The fragmentation and deterioration of old‐growth forest habitat by modern forestry have become a major threat to species diversity in Fennoscandia. In order to develop a conservation strategy for the remaining diversity it is essential to identify the existing diversity and to develop appropriate conservation and monitoring programs. For these purposes indicators of conservation value for administrative prioritization are required. This study examines the predictability of plant and fungal species richness on two spatial scales on 46 isolated old‐growth forest islands (0.17 ‐ 12 ha) in a forest‐wetland mosaic. We explore (1) to what extent area, isolation and stand structure variables can explain the variation in species richness and (2) if richness patterns of individual species groups correlate. Isolation showed no relation to species richness. Area explained 50 ‐ 70% of the variation in total species richness and was positively related to the density of crustose lichens and Red‐list species in island interiors. Stand structure variables explained 28 ‐ 66% of the residual variation in total species richness after controlling for island size, and 15 ‐ 73% of the variation in density of species in island interiors. The highest predictability of species richness was found among substrate‐specific fungi and Red‐list species. Different stand structure variables were found to explain richness in the different species groups, and only among a few species groups species richness correlated. Thus, species richness of one single species group is unlikely to be a good indicator for total biodiversity. The results show that measurements of stand size and stand structure variables may be a strong complementary tool, and sometimes a substitute to extensive species inventories when one aims to estimate and monitor plant and fungal species diversity in old‐growth Picea abies forests.

Evaluating macrolichens and environmental variables as predictors of the diversity of epiphytic microlichens

“…The better performance of macrolichens provides some evidence for the sometimes hypothesized advantage of using indicator and target taxa which share ecological requirements and life-history traits (Beccaloni & Gaston 1995;Bergamini et al 2005). Relationships between richness of microlichens and several indicator taxa were studied by Berglund & Jonsson (2001). They found polyporous and corticoid fungi to be good indicators of microlichen richness with relationships very similar to the ones we found here between macro-and microlichen richness.…”

“…Environmental variables are often much easier to quantify than species numbers of many taxa, and they may be used as a complementary tool when quantifying biodiversity (Berglund & Jonsson 2001;Gustafsson et al 2004). Key variables for the distribution of epiphytic forest lichens include forest stand variables (e.g.…”

“…Key variables for the distribution of epiphytic forest lichens include forest stand variables (e.g. Berglund & Jonsson 2001;Gustafsson et al 2004), variables related to the phorophyte (e.g. Hyvärinen et al 1992;Uliczka & Angelstam 1999), other abiotic variables such as altitude (Dietrich & Scheidegger 1997;Gustafsson et al 2004), and climatic variables (e.g.…”

Concordance between vascular plant and macrofungal community composition in broadleaf deciduous forests in central Italy

“…The growing impact of human activities that contribute to habitat fragmentation and decrease diversity on natural ecosystems has brought with it an urgent need for the development of simple, quick and cost-effective methodologies for quantifying and monitoring changes in biological diversity (Berglund & Jonsson 2001, Heino & Mykrä 2006, Santi et al 2010.…”

“…Finding strategies to identify the state of biodiversity and to develop appropriate conservation and monitoring programs is one of the most important issues in the field of ecology (Gaston 2000, Berglund & Jonsson 2001, Similä et al 2006). The growing impact of human activities that contribute to habitat fragmentation and decrease diversity on natural ecosystems has brought with it an urgent need for the development of simple, quick and cost-effective methodologies for quantifying and monitoring changes in biological diversity (Berglund & Jonsson 2001, Heino & Mykrä 2006, Santi et al 2010.…”