Landscape change trajectory analysis in the assessment of ecosystem space-time properties and dynamics: case study from south-western Finland

Landscape Change Trajectory Analysis (LCTA) can be used to analyse landscape dynamics and to dissect evidences of the major driving forces of landscape change. The emphasis of the change analysis is on the retrospective relationship between the present-day and the past landscape patterns with the aim of identifying the relevant spatio-temporal processes in the landscape. We have tested the use of LCTA approach in the analysis and assessment of ecosystem space-time properties and dynamics within a protected oak forest site in south-western Finland to improve the conservation planning and practise of this key ecosystem. Oak woodlands and forest biotopes represent valuable habitats in the hemiboreal landscapes of Finland and are characterised by dynamics due to nature-human interactions over centuries.The study covered a time span of ca. 300 years and consisted of the following phases. Firstly, spatial analysis and visualisation was done in GIS of selected structural patterns of the present-day oak forests derived from existing forest inventory. Secondly, space-time indicators of forest cover stability and continuity, land use trajectories and boundary dynamics were derived from the spatio-temporal database, which consisted of land cover and land use information from 1690 to 1998. Thirdly, edaphic site conditions, indicated by the wetness, slope and aspect characteristics, were analysed within the current oaks forests. Finally, forest structural and tree species composition were combined with the site-specific edaphic and change dynamics information in GIS. This database was spatially analysed to assess the space-time properties of the oaks forests and to reorganise and cluster the forest patches based on their similarities and differences in the present characteristics and past trajectories of development. The spatio-temporal analysis was based on the applications of cartographic space-time models and statistical and overlay techniques in GIS.