6th October we are celebrating UNESCO's International Geodiversity Day. It is a time to focus on biodiversity's silent partner, on which life and culture on Earth is built.
Natural diversity consists of two parts: biodiversity and its underlying geodiversity, which forms the basis for all life and human cultural diversity. Geodiversity has enabled ancient cultural developments, the industrial revolution and the modern information society. It also lays the foundation for a future based on renewable energy.
So what does geodiversity mean? Simply, the fact that there are many different geological formations in the area in question, both quantitatively and qualitatively. For example, the bedrock can contain several types of stone of different ages, and the soil covering the bedrock can contain soil deposits created at many different stages – moraines, ridges, peat deposits – or other geological phenomena, such as groundwater discharge sites or springs. Geological diversity can be present in the most diverse forms.
Geoparks are naturally areas of high geodiversity. This manifests itself in diverse geological sites. In the Lauhanvuori – Hämeenkangas Geopark, there are several chapters in the development story of the landscape, starting with the events of two billion years ago, continuing to the development stages of hundreds and tens of millions of years ago, as well as the Ice Age and the development after it. In few places in Finland, as many geological development stages and the geological formations created by them can be seen.
The geodiversity center of the Geopark area is located in Lauhanvuori National Park and its surroundings. Most of the geological development phases of the area are represented there. The same stages can also be seen elsewhere in the Geopark area, individually in some places even more spectacular than on Lauhanvuori, but there is no similar entity elsewhere.
The connection between geodiversity and biodiversity is also very noticeable in Kauhaneva – Pohjankangas National Park and Hämeenkangas. In particular, the interaction between glaciofluvial deposits, groundwater and mires creates diverse habitats, good examples of which are the springs of Hämeenkangas.
The connection between geodiversity and cultural diversity can be seen, for example, in the agricultural landscape of Hyypänjokilaakso, the remnants of Haapakeidas bog farms, and the historic peat production areas of Aitoneva. In Karijoki, the handprint of the Iso-Kakkori stonemasons can be seen in the old stone bridges of the river valley, whose original construction method differs from the usual. In the surroundings of Alkkianvuori, the landscape has been shaped by swamp farming, bog forestry and forest research.
The connection of geodiversity, biodiversity and cultural diversity is very visible in Hämeenkangas, where the airport area built on the flat terrace area of the edge formation of the glacier has also become an open heath favored by many rare species. The landscape reminds of the region’s past – once treeless or sparsely forested heath covered almost the entire Hämeenkangas.
In addition to the sites that can be seen today, geological diversity is also visible in the history of the Geopark area. Geological formations, from gravel ridges to swamps and lakes, have for hundreds of years guided the movement of people, the placement of settlements and the development of infrastructure important to the functioning of society. Some of the geodiversity has also been lost in the mists of history, such as the lush peat bogs along the riverbanks, which were cleared for farmland a long time ago.
Finally, a small task: look around you and think about which of the everyday objects and things around you are not related to geodiversity. I’m sure you won’t find many things that are not related to geological diversity in any way.
Text: Pasi Talvitie
Images: Pasi Talvitie, Terttu Hermansson, Mirja Koivisto, Jenni Rankaviita, Joonas Vinnari
Video: UNESCO / Oxford Geoheritage Virtual Conference