The impact of the vegetation of apple orchard edges on quantity and quality structure of predatory hoverflies (Diptera: Syrphidae) communities
SummaryThe research on the impact of apple orchard edges vegetation on quantity and quality structure of predatory Syrphidae was carried out between 2008 and 2010 in the vicinity of Czempiń in the western part of Wielkopolska, Poland. Quality and quantity analyses of Syrphidae communities in the apple orchards and on their edges were conducted; the edges included fields, shrubberies and a road lined with trees and bushes. The total of 35 Syrphidae species were found, which constituted 8.8% of the national fauna of this family. In the orchards 24 species and on the edges 32 species were caught. The total number of specimens of the family was 5080, out of which 2338 were caught in the orchards and 2742 on the edges.. Apple orchards with developed edge vegetation yielded higher abundances of Syrphidae than the orchard bordering on the fields. All the orchards and their edges were dominated by two species, namely Episyrphus balteatus (De Geer, 1776) and Eupeodes corollae (Fabricius, 1794). It was found that the majority of Syrphidae flies communities inhabiting the orchards and their edges showed a high similarity in their quality and qualityquantity structures. The research showed that the occurrence of well-developed vegetation with diversified species on apple orchard edges positively influences the species richness and abundance of predatory Syrphidae occurring in the orchard habitat.
1. The studies included cultural landscapes of simple (agricultural land) and complex (forest) structure in Wielkopolska.
2. The goal of the studies was to define biocoenotic function of marginal habitats such as – shrubs, field border, road borders, and forest edges – structural elements of agricultural landscape making suitable habitats for parasitoid hymenoptera of subfamily Pimplinae (Hymenoptera, Ichneumonidae)
3. The authors wanted to establish:
i. which of marginal habitats are most attractive for Pimplinae;
ii. which of these habitats are similar to forest habitats, due to the qualitative and quantitative structure of parasitoid hymenoptera communities living there; and
iii. whether linear marginal habitats (like road sides) can fulfil the function of ecological corridors for parasitoid hymenoptera, between agricultural and forest habitats.
4. The species diversity of Pimplinae in all the habitats of agricultural landscape and forest environment (national park) was similar.
5. On the forest edges (high heterogeneity landscape), the communities of Pimplinae were most numerous. In the low heterogeneity landscape, the greatest species diversity occurred in shrubs. The majority of Pimplinae populations living in agricultural landscape and forest showed great similarity in their qualitative structure and less similarity in their quantitative structure.
6. The conclusion can be made that marginal habitats of agricultural landscape make attractive environment for parasitoids of Pimplinae and that vegetation alongside roads can make function as ecological corridors.
Invasive plants directly and indirectly disrupt the ecosystem functioning, of which indirect effects, for example, through trophic cascades, are particularly difficult to predict. It is frequently assumed that the impact of an invading species on the ecosystem is proportional (linearly related) to its density or abundance in a habitat, but this assumption has rarely been tested. We hypothesised that abundance and richness of plants and potentially pollinators of wet meadows change as a result of invasion of steeplebush Spiraea tomentosa and that these changes are proportional to the density of the shrub. We selected 27 sites amongst wet meadows habitats invaded by S. tomentosa with coverage ranging from 0% to 100% and examined the diversity of plants, as well as the abundance and diversity of flower visitors (bees, butterflies with moths and flies). Our results showed that the richness of plants, as well as the richness and number of individuals of flower visitors, decrease significantly and linearly with an increase of the S. tomentosa cover. This finding supports the hypothesis that the impact of an invasive species can be proportional to their population density, especially if this species is limiting the available resources without supplying others. Our study is the first to show such an unequivocal negative, linear effect of an invasive shrub on the abundance and richness of potential pollinators. It proves that the negative impact of S. tomentosa on the wetland ecosystem appears even with a minor coverage of the invader, which should be taken into account when planning activities aimed at controlling the population of this transformer species. The simultaneously detected linear dependence allows us to assume that the benefits of controlling secondary populations of the shrub can be proportional to the incurred effort.
The aim of the study was a comparison of species composition and abundance of two insect families, i.e. ground beetles, Carabidae and hoverflies, Syrphidae, occurring on a mix of flowering plants at the two localities in western part of Poland. The studies were conducted in Jarosławiec (Wielkopolska province) and Pągów (Opole province), on the experimental fields belonging to BASF Polska Sp. z o.o., in 2012-2013. Pitfall traps were used for collecting Carabidae while entomological nets as well as yellow traps were used for collecting Syrphidae ecological analyses of ground beetles and hoverflies assemblages showed significant differences between the two compared localities, in particular qualitative evaluation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.