The entomofauna of cultivated fields, fallows and meadows (malaise-trap samples)
1993
Greiler, H.-J. (Karlsruhe Univ. (Germany). Zoologisches Inst.) | Tscharntke, T.
In 1990, effects of abandonment of grain-fields were examined near Karlsruhe (Southwest Germany). Insects of cultivated and uncultivated fields were caught by malaise-traps (each treatment: n = 4):(1) rye fields, (2) one year old fallows sown with clover-grass mixtures, (3) one year old fallows with naturally developed vegetation, (4) two year old fallows with naturally developed vegetation, and (5) meadows with fruit-trees. Further, vegetation of each field was mapped. As was to be expected, results on plant mapping showed a highly significant increase in the number of species with the sequenceof treatment from (1) to (5). But treatment (1) and (2) had the maximum number of insect individuals. With respect to insects, predator-prey relationships showed the same tendency as the species number of plants (an increase from treatment 1 to 5). The numbers of individuals of the Hymenoptera Parasitica (Ichneumonoidea, Chalcidoidea, Proctotrupoidea, Ceraphronoidea, Cynipoidea) did not show such significant differences between treatments. Similarly, the number of parasitoid families did not differ between the five treatments
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