Epsilon Archive for Student Projects

Abstract

In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time.

The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood. Obviously some areas were burnt repeatedly and other areas were not affected at all. An investigation was made from early forest inventories to see if the quantities of volume of standing timber and dead wood was more sparse around the chalets in the northern parts of Sarna-Idre forest common. The results was not clear but indicated higher volumes of wood further from the chalets.

The commercial logging in the region started as late as in the 1860's. During a 40 year period a major portion of the oldest and largest trees was remowed from the forest. In the same period almost half of the quantity of the dead trees were harvested. During the studied period the volume of dead wood decreased with more than 90%.

At an average 1,5% of the landscape area was annually affected of forest fires between the period of 1400- 1850. When the forest became valuable as lumber at the end of the 19th century, the frequency of forest fires declined rapidly. The forest grew thicker and fire regeneration became more sparse.

Through the forest inventories which continually has been done during the 20th century an investigations was made of the structural changes of the forest. The proportion of multistoried stands declined from 86% to 21% between 1889 and 1989. In the beginning of the studied period the mean age was over 200 years and in 1989 it was as low as 74 year. The timber volume declined from 75 cubicmeter per hectar in 1860 to 46 cubicmeter per hectar in 1944. Then the volume slowly started to recover and in 1989 it reached 60 cubicmeter per hectar.

The major changes in the forest structure during the 20th century is the loss of old forestsstands and increase of more conform and younger and even aged stands. The quantities of dead wood has also radically declined. In contrary to the forests of the 19th century with its multistoried, grazed, open landscape, the next centuries forests will be dominated by even aged, conform, younger stands with increasing woodsupplies.