A forest history for the last 10 900 years at the site Storasjo, southern Sweden: implications from beetle assemblages

A continuous Holocene beetle record from southern Sweden is presented and compared with results from a previous study, at Stavsakra. The comparison reveals both regional trends and local differences. The early Holocene, ca. 8900-7500 BC, was characterised by open, pine-dominated woodlands at both sites. Fire and grazing seem to have maintained the open structure and favoured the established vegetation and fauna. During the middle Holocene, ca. 7500-900 BC, the woodlands grew denser. There are no indications of grazing at the sites during this time period, whereas fires were frequent. The late Holocene, ca. 900 BC to the present, was characterised by a progressive opening up of the woodlands, mainly by land use such as grazing and clearance by fire. This process started ca. 2400 BC at Stavsakra, where there were already settlements during the late Neolithic. At Storasjo, which probably was mainly used as outland until medieval times, the woodlands gradually opened up. Heather-dominated heathland formed between ca. 900 and 800 BC at both sites. The two studies confirm that insect data contribute unique information concerning changes in structures and disturbances in forest ecosystems on long timescales. Copyright (C) 2010 John Wiley & Sons, Ltd.