Overwintering of arthropods in soils of arable fields and adjacent semi-natural habitats

Lukas Pfiffner and Henryk Luka

Sponsor(s)/Partners

Financial support provided by the Basellandschaft canton administration, and the Swiss Agency for the Environment, Forests and Landscape.

Purpose

To compare the overwintering arthropod populations in organic and intergrated managed arable fields with populations in various adjacent semi-natural habitats.

Methods

These landscapes were defined in northwest Switzerland to include 2 arable fields at an integrated organic farm and six different adjacent field margins and semi-natural habitats. On three dates between December 1995 - January 1996 soil samples were collected from six paired habitats. Large arthropods were sorted manually while smaller ones were mechanically extracted with a modified MacFayden apparatus.

Results

With one exception all comparisons showed a wider range of arthropods, specifically staphylinids, carabids, spiders and chilopods, in semi-natural habitats. The highest population number and diversity were found in the sown wildflower strip, hedge, permanent meadow and under cherry trees on the organic farm. The organic land, which was more diversified, had 2 to 5 times the abundance of arthropods than the integrated sites.