Arkinmäki – a New Area Conserved in Rauma

The Finnish Natural Heritage Foundation obtained its third conservation area in the Satakunta region with the purchase of the 3,2-hectare Arkinmäki forest in Rauma. The deal was financed by an association called Rauman seudun luonnonystävät with the help of the resources donated by the association for the conservation fund of the Satakunta nature conservation district. The forest is located in the Sorkka village in Raumo, where it is embraced by the eastern section of the valuable Prami grove zone.

- It is thanks to our predecessors involved in the association. Our activists worked hard during the 1980s and 1990s to raise funds for the new conservation area by selling products, for instance, according to Esa Hankonen, the chairman of the association. - We are glad to find a protectable forest close to the Prami groves because our activists used to make an effort to have them also placed under protection.

The groves belong to the Natura 2000 network through the 76-hectare diabase area of Rauma. The natural values provided by the area are based on the diabase contained in the bedrock and appearing in the form of furrows developed over 1260 million years ago as a result of volcanic eruptions. The diabase ground is suitable for demanding rock plants, forest plants, and swamp plants.

The small Arkinmäki forest is a home for diversity.

Over half of the area, the north section in particular, is dominated by spruces with the fresh and grove-like heath enriched by grove blotches and swamps. The spruces are middle-aged, and they grow thick with a few mighty birches standing among them. The old trees toppled by the wind have started to decay.

The field layer provides a home for the common hepatica, the Alpine currant, and the alder buckthorn. The common hazel has also found a place to live in the eastern edge of the forest – on the Satakunta coast, the common hazel only appears in the Sorkka village in Rauma.

The environment is diversified by wetlands. In the heart of the forest, there is a hollow between the rocky slopes, and in the eastern section, there is a swamp with a few trees, and they both belong to the valuable forest environments protected by the Finnish law. In the southern section, there is an undrained flood meadow of several hundred square metres, and closer to the southern border, it has turned into a swampy wetland as a result of a drainage.

The Arkinmäki area includes sections that can be restored either naturally or manually: sapling stands of birches and willows, embroidered by small spruce-covered islets, as well as a piece of a swampy ditch to be blocked on the southern border.

Arkinmäki is the 48th conservation area of the foundation, the third one in the Satakunta region.

Photo: Esa Hankonen.