Assessment of Western taiga habitat in Lahemaa National Park, Estonia

Abstract

Diverse structural elements play an important role in sustaining biodiversity in old-growth forests. Therefore, it is important to have thorough knowledge about these habitats and their condition in protected areas. Metsakorralduse Büroo OÜ conducted a large-scale Natura 2000 forest habitat inventory that covered 60% of Lahemaa National Park (LNP) area. Western taiga habitat data (7,191 ha) from this inventory was used for analysis of forest stages. The data was grouped according to stand classes by total area and these classes were compared by deadwood occurrence and relative density. For more precise evaluation of coarse woody debris (CWD) we used 27 sample plots from the Estonian Network of Forest Research Plots (ENFRP) located in LNP. The biggest areas of Western taiga habitat were covered by mature and old stages. CWD occurrence (over 5 m³ha⁻¹ of snags and logs) by habitat representativeness is higher in old and natural forest classes. This logical result is overshadowed by the outcome that the CWD was not substantially present on 32% of the area in the old-growth forest class. This indicates that these areas lack the potential of biological legacies to provide critical niche habitats for different species. The study shows that the CWD quantity in Estonian conditions is similar to that reported in previous studies in this region, but because many of the older forest stage classes do not have any CWD present, these areas should include ecological restoration practices in their conservation planning. By creating snags, logs and gaps in these areas, we are able to create better structural variability and include wood into different decay processes.