Arthropod Communities in Different Agroforesty Landscapes

The responses of arthropod communities to an agroforestry landscape was studied at the Leeds University Field Station (Bramham), in northern England. The experimental design consisted of tree rows (containing four species of furniture timber trees, hazel bushes and grass alleys between the tree rows), forestry plots (comprising three species of timber trees and hazel bushes) and natural woodlots (consisting of mostly pine and beech trees). Forty tree sparrow nest-boxes with guards were constructed to study the structure of this model community. The material used for nest construction was determined based on a used tree sparrow nest obtained from a hedge at the field station. Numbers of arthropods found in tree rows were significantly higher compared to both the forest plots and woodlots. Similarly, the number of green lacewings, flies and beetles were all significantly higher in the tree rows than the forestry plots and woodlots. However, no significant difference between the varying resources of artificial nesting materials was found in total fauna. The common earwigs, Forficula auricularia were attacked by a tachinid fly, Triarthria. setipennis. The rate of parasitism was 43%. This tachinid fly was further parasitised by two hymenopteran, the pteromalids, Dibrachys. cavus and D. boarmiae. There were no significant differences observed between the brood sizes of the tachinid hyperparasitoids.