Distance of agricultural land from natural habitat affects the functional trait diversity and species diversity but not abundance of Hymenoptera parasites

In agricultural landscapes, natural habitat may enhance species diversity or the abundance of natural enemies in arable lands, and thereby suppress pest populations effectively. However, there is a lack of studies in Tropical regions about these interactions. The aim of this study was to investigate the community structure of Hymenoptera parasites at two distances (<200 m and > 400 m) from edges of natural habitat to cucumber fields. This research was carried out in twelve cucumber fields in West Java, Indonesia. Hymenopteran parasites were collected by yellow pan trap and hand picking of parasitized lepidopteran larvae. In total, 19 family and 130 parasitoid species, comprising 19,167 individuals, were collected in our experiments. A number of 56 (43.1%) hymenopteran parasites species found only in cropping with a certain distance away from the natural habitat. Of these, as many as 39 species (69.6%) hymenopteran parasites found in cucumber fields within close natural habitats, while the crop is being of natural habitats found 17 species (13.1%). Moreover, the functional diversity of hymenopteran parasites tends to increase on cropland closed to natural habitat. We conclude that distance of agricultural land to natural habitat affect hymenopteran parasites.