The influence of anthropogenic pressure on the structure of communities of parasitoids of the Pimplinae subfamily (Hymenoptera, Ichneumonidae) inhabiting urban green areas

Urban green areas have favourable conditions for the development of phytophagous species, which feed on plants and thus reduce their aesthetic value. The population of plant pests can be limited by parasitoids of the Pimplinae subfamily. The aim of this study was to determine the influence of low, medium, and high anthropogenic pressure on the qualitative and quantitative structure of Pimplinae communities inhabiting urban green areas and to determine the influence of this pressure on the catchability of insects. The research was conducted between 2014 and 2016 in allotment gardens in the city of Poznań. The research showed that there were individual species with the highest frequency of occurrence in the communities of parasitoids which were affected by low anthropogenic pressure. On the other hand, in the communities exposed to high anthropogenic pressure the frequencies of occurrence of individual species were similar to each other. There were significant differences in the catchability of parasitoids into individual Moericke traps. The research showed that the richness of plant species had the greatest influence on the qualitative and quantitative structure of Pimplinae communities, whereas the size of the area, distance from the city centre, and the intensity of air pollution exerted lesser influence.