Conservation Through Management – Cut Wood as Substrate for Saproxylic Organisms

Lindhe, A. 2004. Conservation through management – cut wood as substrate for saproxylic organisms. Doctor’s dissertation. ISSN 1401-6230, ISBN 91-576-6534-6 The experience of naturalists indicate that many forest species have become more rare as a result of intensive forest management. As less dead wood is one of the key changes in most forests, saproxylic organisms tend to be especially vulnerable. So far, countermeasures have focused on setting aside reserves and key-habitats. However, while unmanaged reserves are likely to be important for many species, such areas provide little substrate for organisms adapted to habitats created by recent fires or other stand-level disturbances. Such species potentially benefit more from increased production and retention of dead wood in managed forest landscapes. This thesis evaluates artificially created high stumps as hosts for saproxylic beetles, and stumps and logs as substrates for saproxylic fungi. The studies are based on seven years of data from cut wood of various tree species, diameters and conditions of sun-exposure in Fagerön (Uppland, Sweden). The results demonstrate that hundreds of beetle species, including many red-listed species, utilise high stumps, and that two thirds of this fauna favours stumps in semior fully sun-exposed conditions. Thus, high stumps in logging areas and other open sites are potentially very valuable tools for conservation of saproxylic beetles. Cut wood, especially large diameter logs, also hosted numerous species of saproxylic fungi. Generally, most such species were little influenced by exposure. Thus, cut logs may support fungal diversity, both in managed forest landscapes and in forest reserves and key-habitats.