The subject of the study as to get an overview of the changes in forest cover in the last 1,500 years. The research covered an area of 4,250 hectares, the natural boundaries of which are determined by the lowering of Lake Jasień. The reconstruction of forest cover evolution in the older part of the studied period (5th/6th‒17th centuries) was conducted on the basis of geological structure analysis of 9 landforms. Within them, slope sediments were separated, the emergence of which was associated with deforestation and the development of agricultural land use. The approximate age of these events was determined on the basis of 11 examples of radiocarbon dating of the material taken under the slope sediments and within their area. Changes during the younger period (1618–2017) were examined using large-scale cartographic materials and an orthophotomap as well as data from the Forests Data Bank.

It was found that from 5th/6th till the mid-19th century, forested area used to decrease, and deforestation grew in two periods. The first of them took place from the turn of the 5th and 6th centuries till the 9th century and the second between the 12th and the mid-19th century, when afforestation rate dropped to the lowest point ever, recorded of 20%. From the mid-19th century forest cover started to increase systematically. In 2017 forests covered 69% of the studied area and that was the highest value in over 400 years.

Afforestation rate and the size of forest cover changes in the studied area in recent 400 years most often did not coincide with changes in Western Pomerania. This proves that local transformations of tree stands could have significantly departed from the general trend for much larger areas.