Assessing biodiversity and conservation status of the Natura 2000 forest habitat types: Tools for designated forestlands stewardship

摘要

The maintenance of biodiversity in forestlands has become one of the major concerns of forestry in the European Union (EU) as well as globally. The EU and its member states implement it through the Forest Europe process, which promotes sustainable forest management, and the EU Council Habitats Directive (HDirective). Within the Forest Europe process, indicators and management concepts are developed for forests in general, whereas the HDirective is concerned with the forest habitats and forest habitat types of the Natura 2000 network. Although the HDirective helps to tackle a broad range of biodiversity problems, there remain some open issues, including the vaguely defined concept of a forest habitat type, conservation status of a forest habitat type, lack of defined indicators of conservation status and undeveloped concepts for the stewardship of forest habitat types. This study addressed most of these open problems. The methods were tested in three habitat types in Slovenia: 9110 - Luzulo-Fagetum beech forests, 91K0 - Illyrian Fagus sylvatica forests (Aremonio-Fagion) and 91L0 - Illyrian oak-hornbeam forests (Erythronio-Carpinion). To make the definition of a forest habitat type more concrete, a hierarchical order was introduced into the current concept of forest habitat types. A hierarchal relation between forest habitat types and their subtypes was established by employing a bottom-up strategy and classification key. This key was developed through exploring the vegetation and eco-geographical characteristics of the forest habitat subtypes. An assessment of the conservation status of forest habitat types was performed using 18 indicators. Only the indicators supporting the favorable conservation status definition outlined in the HDirective were selected. The stewardship of forest habitat types was demonstrated through assessment points depicting the present, ideal and desired states of the indicators. The points were constructed through a basic statistical analysis, vegetation and forest planning models and literature review. The results showed that dividing the three forest habitat types produced less heterogeneous forest habitat subtypes. The indicators and the assessment points performed well as they suggested the preferred course of development of the three forest habitat types. Because of their applicability in different environments, the methods can be used in other European countries and regions and beyond. (C) 2015 Elsevier B.V. All rights reserved.