The importance of grazing and fire for the open landscape and biodiversity

A unique research project is under way in the Ecopark right now. We are investigating how young saplings and vascular plants are affected by grazing and fire – two important natural disturbances. The purpose is to determine which methods can be used in our nature conservation work in order to maintain an open landscape.

Many scientists believe that before man started working the land, it was the large herbivores and naturally occurring fires that shaped the landscape. When agriculture later took over, the process was continued in the form of grazing cattle, mowing and so-called slash-burning. But today, the number of grazing cattle has fallen sharply and every effort is made to avoid fires. The result is that once-open landscapes rapidly become overgrown, something that is not conducive to diversity that requires a lot of light and continuous grazing.

What we want to study in our research is how different trees and shrubs, and also vascular plants, react to different kinds of disturbances. A disturbance is something that changes the environment in some way. It can be a prolonged drought, a flood or, as in our case, fires and grazing by large herbivores. You might imagine that such factors destroy nature, but it isn’t that simple. Nature needs to change if as many different species as possible are to thrive. We a set-up of 24 test sites in the Ecopark where we have planted various trees and bushes, as well as different types of vascular plants. The test areas are grazed by our own cattle and are subject to burning in different sequences. Several times a year, an inventory is carried out of the trees, shrubs and vascular plants to see how this treatment is affecting them.

The sowing of vascular plants is done using a special frame to make it easy to find the sowing spots during the inventory.

The trees are measured and examined several times a year to see how they are being affected.

This research is unique. It’s the first time anyone has studied the effect of both grazing and fire in this fashion at our latitudes. Similar studies have been conducted in Africa and also in Bialowieza, Poland, one of the last ancient woodlands in Europe. But those studies focused mainly on the impact of grazing by wild animals. We believe that using domestic grazing animals allows us to carry out a more controlled study. The hope is that the results will give us a better understanding of how we can preserve our species-rich landscape where flora, butterflies and other creatures thrive.

The project involves researchers from the Swedish University of Agricultural Sciences, the Mammal Research Institute in Bialowieza, Poland, and University West in Trollhättan. The study is supported by the Hasselblad Foundation and Thuréus forskarhem, and Svenska Skogsplantor AB donated some of the seedlings for the research.

For further information, please contact
Karin Amsten, research student, Nordens Ark, 0523-791 85
Mats Niklasson, scientific leader, Nordens Ark, 0523-797 82