GIS-analys av potentiella habitat för mindre hackspett (Dendrocopos minor) : En analys i Karlstads kommun

Sammanfattning: The purpose of the study is to develop a method that generates areas in the municipality of Karlstad that satisfies the habitat area requirement for the bird species lesser spotted woodpecker (Dendrocopos minor). The purpose is also to compare two different databases (kNN-Sweden and the Vegetation Map). Habitat area requirement for lesser spotted woodpecker is 40 ha of forest dominated by deciduous trees, which may be fragmented over a maximum of 200 ha. The software ArcMap was used to developed method to generate habitat areas, based on input from the kNN-Sweden and the Vegetation Map databases. The habitat areas were reviewed and compared by overlay analysis and compared to reported observations. Generated habitat areas from the kNN-Sweden database and generated habitat areas from the Vegetation Map database differed significantly. The format of the input data and the threshold values are probably contributing reasons of the difference. An important shortage of the kNN-Sweden database is that a buffer zone around the water surfaces at generalization has been masked off and hence the volume of mature deciduous forest generally underestimated. The number of observations of lesser spotted woodpecker within the habitat areas differed between the kNN-Sweden and the Vegetation Map that fulfilled the requirement. The Vegetation Map had 138 observations of lesser spotted woodpecker while the KNN-Sweden only had 38 observations.