Effects of management cessation on hoverflies (Diptera: Syrphidae) across Austrian and Swiss mountain meadows

Abstract

Abstract. Extensively managed grasslands, particularly in mountain regions, are considered to be one of the most diverse agroecosystems worldwide. Their decline due to land use abandonment affects the diversity of both plants and associated pollinators. Extensive grasslands constitute an important habitat type and food resource for hoverflies (syrphids); however, not much is known about the effects of abandonment on this important pollinator group. In the present study, we investigated how abandonment affects species richness and the composition of syrphids in mountainous meadows. We recorded the richness of vascular plants, vegetation cover, flower cover and the surrounding landscape to examine whether and how syrphids are affected by plant and landscape parameters. We investigated the species richness, abundance and species composition of syrphids by sweep netting and by using observation plots in 18 semidry meadows across two Austrian regions and one Swiss region. For each region, we selected three meadows abandoned for more than 20 years and three annually mown non-fertilized meadows. Abandonment or mowing had no significant effect on the total number of syrphid species or individuals or on the number of aphidophagous and non-aphidophagous species and individuals. However, the total number of species and the number of non-aphidophagous species significantly increased with the increasing number of plant species. The surrounding landscape and other plant parameters showed no association with the assessed syrphid parameters. Although syrphids were unaffected by abandonment, higher syrphid species numbers in response to a higher plant richness in annual mown meadows suggest that the management of mountain meadows is beneficial in preserving syrphid richness.

Understanding the Dynamics of Sex-Specific Responses Driven by Grassland Management: Using Syrphids as a Model Insect Group

“…It is known that extensive grasslands support high biodiversity, including an abundance of pollinators like syrphids [54]. This increase in biodiversity is more noticeable when pollinator diversity in extensive grassland was studied compared to abandoned grassland [55].…”

Soil and Vegetation Characteristics of Grassland Have a Greater Influence on the Abundance and Diversity of Earthworms than the Mowing Intensity in a Managed Nature Reserve

“…When grassland is no longer managed, it tends to revert to a more natural state, with substantial changes in plant and aboveground animal communities [6,7], but also in terms of soil biodiversity and ecosystem functioning [8][9][10][11]. However, while the effects of grassland management on vegetation parameters [12][13][14] and aboveground faunal communities [15][16][17] are well documented, much less is known about the potential effects on soil organisms such as earthworms [18,19].…”

Effects of Traditional Orchard Abandonment and Landscape Context on the Beneficial Arthropod Community in a Mediterranean Agroecosystem

“…Many studies have attempted to shed light on this topic, and the rough conclusion seems to be that in Europe, agricultural abandonment reduces overall biodiversity, especially in traditional landscapes and after long periods [ 11 , 16 , 17 ]. Conversely, some studies have found increased diversity in late successional stages or an overall beneficial effect of maintaining both managed and abandoned plots in the landscape [ 18 , 19 , 20 , 21 , 22 , 23 ].…”