Agrarbiodiv 5
Caterpillar diversity in field margins of different crops.
Schotthöfer, Annalena; Hahn, Melanie; Brühl, Carsten A.: Institut für Umweltwissenschaften, Universität Koblenz-Landau, Fortstraße 7, D-76829 Landau, Germany schotthoefer@uni-landau.de Field margins play an important role as habitats for many plant and animal species. In agricultural landscapes they account for a large part of semi-natural habitats. However, field margins can be influencedbyinputsofagrochemicals(pesticidesandfertilisers)fromadjacentfieldsorplantations or can be influenced by management activities such as mowing. An important group of organisms living in field margins are butterflies (Lepidoptera). In Germany, 200 diurnal and 2000 nocturnal species are verified. Today, most studies address the ecology of adult butterflies while the larval stage is left unattended although the habitat demands of both can differ a lot. Additionally, caterpillars play an important role in ecosystems’ food chains as primary consumers and also as food source for e.g. birds and their nestlings. Many caterpillars show strong specialization on their food plants (oligophagous or monophagous species). Because of their lower mobility compared to the adult stage, caterpillars rely notably on the presence of suitable habitats and a high quality of food plants for their development. Furthermore, as phytophagous organisms caterpillars consume contaminated plant material or are exposed to pesticides directly. Indirectly, they are affected by the loss of food plants caused by herbicides. Hence, they are especially susceptible to influences of agricultural activities. The aim of this diploma thesis is to find out whether field margins act as habitat for the development of caterpillars and whether margins of several crop plants differ in their suitability as habitat. Severalfieldmarginsofdifferentcrops(cereals,vine,andfruits)aswellascontrolareas(meadows) were selected in a study area around Landau (southern Rhineland Palatinate). The caterpillars were sampled using a sweep net on a transect along the field margins and the control areas. If possible they were identified after collection. The vegetation of each sampling site was recorded as well and the existence of potential food plants was noted. The study was carried out in two to three time intervals from May 2011 onwards. First results of this study will be presented and discussed.
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Tagungsband SETAC GLB Jahreskonferenz 2011 „ÖkoTOXIKOlogie und UmweltCHEMIE: Grenzen überwinden“