project Nature-based Management of beech in Europe
Introduction
According to the original time schedule Nat-Man should be finished by now. However, we have ecided (in agreement with the Commission) to continue for another 8 months until September 2004. The aim of this extension is to close the project with a joint conference/ workshop with the European Pro Silva organization.
At the workshop we will present and discuss our results and proposed management guidelines in a forum of researchers and end-users. You can read more about the conference at the last page of the Newsletter.
A number of Nat-Man research reports are now available at the Nat-Man web-site: ww.flec.kvl.dk/ natman. Studies of dead wood in natural and managed forests have been an important part of the Nat- Man project (look for the reports at the web-site). A thoroughly integrated research effort among the partners of Nat-Man has lead to impressive new insights in this field. Our results have a clear address to the current development of pan European criteria and indicators for sustainable forest management (MCPFE). This issue of the Nat-Man Newsletter presents an overview over some of the findings.
Dead wood is an important component in natural forests. It provides habitats for maintaining biodiversity, plays an important role in forest productivity, and secures long-term carbon storage. Recently, dead wood has become one of nine Pan-European indicators of sustainable forest management and biodiversity conservation. Moreover, dead wood is an operational and quantitative stand level indicator, which can be measured by simple and reliable tools. Dead wood quantities are, however, normally much lower in managed forests than in unmanaged old-growth forests, and in the interest of sustainable forestry and biodiversity conservation, efforts are being made to increase the dead wood levels in managed forests. Nevertheless, the knowledge about the dynamics, i.e. the quantities, temporal fluctuations and spatial distribution of dead wood in forest reserves of Europe is small and fragmented with some forest types being intensively studied whereas others are sparsely researched. Moreover, we need information
on how results from dead wood research can be transformed into practical management guidelines for sustainable forest management. In this newsletter we focus on dead wood in European beech forests.
The three main topics are 1) dead wood quantities, 2) nutrient and carbon storage in dead wood, and 3) biodiversity and dead wood.
Dead wood volumes in European beech forests
Katrine Hahn and Morten Christensen
In contrast to North America and boreal Europe, there are no reviews of the natural dead wood levels in the temperate zone of Europe, where beech is a dominant species. In Nat-Man we therefore collected data on dead wood in as many European beech forest reserves as possible. The aim was to provide preliminary estimates of dead wood volumes to be used as a reference for sustainable forest management. Our study included 86 beech forest eserves, covering most of the distributional range of beech forests in Europe .
We found a high variation in dead wood volumes between forest reserves, ranging from almost nothing to 550 m3/ha. We also found that the total dead wood volume depended significantly on forest type, reserve age and living wood volume. This means that montane
forest reserves have more dead wood than lowland forest reserves, and that older forest reserves and forest reserves with higher living volume have higher dead wood volumes. Moreover, fallen dead wood (logs) contributed more to the total dead wood volume than standing dead wood (snags), and the volume of standing dead wood was almost twice as high in montane than lowland forest reserves. Finally, we observed considerable variations in
dead wood volumes over time due to the effect of strong disturbances like windthrow. In northwest Europe, the collapse of formerly managed, even-aged stands may also lead to extraordinary high volumes of dead wood shortly after reserve establishment.
The complexity of factors influencing dead wood volumes has implications for both forest management and biodiversity conservation. Measures to increase dead wood volumes must therefore be carried out in accordance with local forest types and disturbance regimes. In order to fulfil the requirements of as many wood-depending organisms as possible, it is thus
important to preserve not only larger amounts of dead wood, but also dead wood of ifferent types as well as securing a long-term continuity of dead wood.
How good is our reference? The question of how close to a reliable reference for sustainable forest management our data from European forest reserves are, is highly interesting. One
important limitation to the data material is the lack of observations from southern Europe, which means that guidelines are only for north and central European beech forest types. Another constraint is the influence of former anthropogenic activities, which has altered
forest structure and species composition. Further, a harmonisation of sampling design, including minimum diameter sampled and sample size would increase the comparability of data, possibly in cooperation with coordination of sampling in national forest inventories.
Further reading:
Christensen, M., Hahn, K., Mountford, E.P., Wijdeven, S.M.J., Manning, D.B., Standovár, T., Ódor, P., and Rozenbergar, D. 2003. A study on dead wood in European beech forest reserves. Nat-Man Working report 9.
Volumes of dead wood (m3/ha) in old and young forest reserves, with indication of forest type (lowland; montane).