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- Dahms, Henriette, et al.
(author)
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Contrasting diversity patterns of epigeic arthropods between grasslands of high and low agronomic potential
- 2010
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In: Basic and Applied Ecology. - : Elsevier BV. - 1618-0089 .- 1439-1791. ; 11:1, s. 6-14
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Journal article (peer-reviewed)abstract
- Abstract in UndeterminedIncreasing demand for food, fuel and fibre promotes the intensification of land-use, particularly in areas favourable for agricultural production. In less-favourable areas, more wildlife-friendly farming systems are often either abandoned or under pressure of conversion, e.g. for bioenergy production. This raises the question, to which extent areas of different agronomicpotential contribute to regional biodiversity. To approach this question on a regional scale, we established our study within a region where sites of high and lowagronomicpotential (AP) alternate on a small spatial scale. We selected 13 high-AP and 13 low-AP grasslands to quantify the contribution of these classes to the regional diversity of four epigeicarthropod taxa (ants, springtails, functional groups of ground beetles, and spiders). The regional diversity (γ) was partitioned into species richness per site (α-diversity), diversity among sites within one class (βwithin-diversity), and diversity between the two classes (βbetween-diversity). The β-diversity generally accounted for the largest share of the γ-diversity, with patterns of diversity components being highly taxon- and class-specific. Carnivorous carabids had a higherα-diversity at high-AP sites. Ants, springtails, and cursorial spiders had a higherβwithin-diversity in low-AP grasslands. Low-AP sites also harboured many more species that occurred exclusively in one grassland class. We conclude that grasslands that may be unfavourable for agricultural production contributed more to regional diversity of epigeicarthropods than favourable grasslands. We therefore suggest that future agricultural schemes should promote arthropod biodiversity by specifically targeting agri-environment schemes or other wildlife-friendly farming approaches to areas of lowagronomicpotential, since this bears the greatest potential to preserve a comparatively high species turnover (β-diversity) and in consequence high regional diversity.
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| 2. |
- Dahms, Henriette, et al.
(author)
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Restoration of Seminatural Grasslands : What is the Impact on Ants?
- 2010
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In: Restoration Ecology. - 1061-2971 .- 1526-100X. ; 18:3, s. 330-337
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Journal article (peer-reviewed)abstract
- The number of species-rich seminatural grasslands in Northern Europe has decreased significantly due to the abandonment of traditional land use practices. To preserve these habitats, an increasing number of abandoned and overgrown grasslands have been restored by cutting down trees and shrubs and reintroducing grazing. These practices are considered a useful tool to recover the species richness of vascular plants, but their impact on other taxa is hardly known. Here we studied ants as one important group of grassland insects. We investigated (1) the effects of restoration of nongrazed and afforested seminatural grasslands, compared to continuously managed reference sites; and (2) the modulating impacts of habitat characteristics and time elapsed since restoration. We found a total of 27 ant species, 11 of these were characteristic of open habitats and seven characteristic of forests. Neither species richness per site nor the number of open-habitat species, nor the number of forest species differed between restored and reference sites. Yet, within the restored sites, the total species richness and the number of open-habitat species was positively related to the time since restoration and the percentage of bare rock. High frequencies of most open-habitat species were associated with low vegetation, older restored sites, and reference sites. Most forest species showed their highest frequencies in tree- and shrub-dominated habitat. We conclude that restoration efforts have been successful in terms of retrieving species richness. A regular and moderate grazing regime subsequent to the restoration is suggested in order to support a high abundance of open-habitat species.
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