Ten years later, half of all oil species disappeared from the parks in Malmö, while the number of species in other green areas remained unchanged. A new study points to the challenge of preserving untouched green areas where butterflies thrive when densely packed.
The younger mitter needs the untouched grass to survive in its larvae. Commodity photography.
In the years from 2006 to 2015, Lund University, in cooperation with SLU, invented butterflies in the parks and green areas in Malmö. In the traditional parks, half of all butterflies have disappeared during this period. In the less-favored areas, the species also disappeared, but they were replaced by new ones, so over time the species kingdom was almost the same.
– There are several aspects that make biodiversity important in cities. In part, the very biodiversity and pollination services that insects do, "says Anna Person, a researcher at the Center for Environmental and Climate Studies at Lund University.
"Then there is also value in experiencing biodiversity We often have the opportunity to experience the nature in our daily life and there are studies that show that today we are so urbanized that we have lost our understanding of nature Young people can not cater for these species to disappear because the nature they are accustomed to is so poor on its own, she continues.
Butterflies feel better in meadows and untouched areas, the so-called ruderamark where the butterfly hotels are located. There the old butterflies can drink nectar and the larvae eat other parts of the plant. The larvae are picky and can survive only a few plant species.
The study highlights the importance of preserving untouched green areas when urbanization becomes more compact. This not only wins butterflies but also other pollinating insects.
"These are just very well-managed, heavy parks that lose most species, which shows that there is great value in thinking about how to care for the green area and maybe dare to have meadows with more home-grown plants," says Anna Person .
Butterflies and host plants
There are about 150000 different butterflies on the host. There are more than 2800 species in Sweden.
Adult butterflies can drink nectar from several different plants. But they lay eggs on certain plants that the larva can eat, the so-called host plants. Butterflies have evolved along with the growth of their host and have adapted their digestion and what substances they can destroy and receive after the growth of the host.
For example, lemon oils are dependent on brakes and diapers. The larvae of Kamgrassfjäril, the mower and the small moth larvae live in a few simple grass species and therefore depend on the fact that the grass is not cut off.
Source: Lund University