Part of my studies are focussed on the early Holocene vegetation and climate development, and the establishment of tree species and development of forests after the last glacial period about 10 000 years ago. Among the key questions today are the timing of the de-glaciation and when the first tree species arrived in the Scand Mountains.

Part of my research is on the relation between human exploitation of natural resources and the vegetation changes during the last ca. 2000 years. Since humans became settled in different regions in Sweden they have used the forests for a multitude of purposes, i.e. domestic cattle grazing, hay-making, and as a resource for timber and charcoal used for metal production, mining. In northern Sweden the establishment of settlements since at least AD 500 also included agriculture, and part of the forest land has also been cut and used for cultivation, such as cereals. Mires have been manipulated for at least a thousand years to increase mire hay production.

I am mainly working with a method called pollen analysis. Pollen grains are produced in enormous amounts by a large share of our plants. The pollen grains are well dispersed and also preserved in our lake sediments and peat bogs where they are identifiable to species, still after thousands of years. With time the sediments and the accumulating peat layers where the different plant and animal remnants are preserved build up biological material in different layers in a stratigraphic way. Each year new material is added on top of older layers and so the oldest remnants are in the bottom of the stratigraphy and the youngest on top of the layer. In this way the sediments and peat bogs can be considered as natural biological archives where thin layers of biological material form a detailed imprint of the local environment from a given time.