Biodiversity and its Assessment in Boreal and Nemoral Forests

Abstract

We review species richness in major organism groups, mainly using examples from northern Europe. A high proportion of these species is forest living, and large numbers are dependent on decaying wood. Biodiversity can be assessed at various scales using two different principles. One is to use features, such as ancient and dead trees, known to be important for a large number of species. The other method is to choose species or groups of species known to indicate high biodiversity or presence of many red-listed species. We argue that any serious biodiversity assessment method should include the most species rich organism groups, for example insects. In the present paper we point out the most important features for high biodiversity (old trees and large dead trees), and review the quantities of these features in near-virgin forests. The natural disturbance regime of a region should be the basis for defining a suitable scale and the appropriate features for biodiversity assessment. Possible indicator species for high biodiversity in northern Europe are suggested, based on previous investigations. Among epiphytic lichens and wood-living beetles there are many potentially useful species in addition to vascular plants in the nemoral forest. Among vertebrates, woodpeckers and grouses seem to be the most useful. Validation tests for indicator structures and species are largely lacking but urgently needed. The implications of possible delayed local extinctions are important to bear in mind when managing for sustainable forestry. The knowledge of forest history is useful when developing cost-efficient measures.

Species variables or environmental variables as indicators of forest biodiversity: a case study using saproxylic beetles in Maritime pine plantations

“…Despite these criticisms the two saproxylic beetle species that have been proposed as indicators of species richness in oak forests (Osmoderma eremita and Cerambyx cerdo) are easy to catch and identify (Buse et al, 2008;Ranius, 2002). Furthermore the saproxylic beetles suggested by Nilsson et al (2001) as potential indicators of biodiversity in northern European forests are also species that were easy to identify.…”

Restricted dispersal in a flying beetle assessed by telemetry

“…In contrast, forest beetles dependent on ephemeral resources that only develop one generation in each habitat have dispersal ranges of several kilometres during their adult life-time (e.g. Nilssen 1984;Creighton and Schnell 1998;Cronin et al 2000, Nilsson et al 2001). …”

Factors influencing the species composition and richness of herb layer in old boreo-nemoral forests

“…See on erinev ka metsakoosluste arengust fragmenteeritud ja sekundaarsetes metsamaastikes, kus on näidatud puistu rohurinde suktsessiooni jätkumist ka küpsetes metsades (Brunet & Oheimb, 1998;Vellend, 2003;Kohv & Liira, 2005). Metsade ajaline ja ruumiline järjepidevus on oluline eelkõige vähese levikuvõimega ja kitsalt vanade metsade struktuuriga kohastunud liikidele püsimisele kooslustes (Berg et al, 1994; Vanade salumetsade rohurinde koosseis ja seda mõjutavad tegurid Unauthenticated Download Date | 5/12/18 5:17 PM Hermy et al, 1999;Nilsson et al, 2001;Flinn & Vellend, 2005;Marozas et al, 2005). Paistab, et salumetsade taimede levik uuritud kooslustesse ja koosluse sees ei ole olnud limiteeritud, sest uurimisalad paiknesid suurema metsamaastiku sees, tagades liigifondi liikide kättesaadavuse.…”