| 1. |
- Gunnarsson, Bengt, 1954, et al.
(författare)
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Effects of logging residue removal on ground-active beetles in temperate forests
- 2004
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Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127. ; 201:2-3, s. 229-239
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Tidskriftsartikel (refereegranskat)abstract
- Logging residue ("slash") left on clear-cuttings may affect the microhabitat complexity, and thereby indirectly the beetle (Coleoptera) populations. In three regions (West, North and East) of south and central Sweden, we studied short-term effects of slash removal on species richness and abundance of beetles, collected by pitfall trapping in 16 clear-cuttings (<1 year old) in coniferous and mixed forests. The sites were managed in two alternative ways, either slash was removed (SR), or slash was left (SL). Overall, the number of morphospecies per trap was significantly higher on SL sites than on SR sites. Species richness differed significantly between the regions, the Western region being the poorest in number of species per trap. Rarefaction plots of species richness in four sites suggested that accumulation rate of species differed between two SR sites but rates were similar for two SL sites. Microhabitat structure was measured by aboveground height of slash heaps. Slash height was positively correlated with the number of sticks in slash heap and fractal dimension, respectively. There was a positive relationship between the number of individuals per trap and slash height in SR sites in the Western and Eastern regions, but not in the Northern one. We concluded that extensive slash removal leads to impoverish species richness of Coleoptera. at a local scale. Slash heaps left on site may provide important refuges for ground-active beetles. Moreover, our results supported the general theory that microhabitat structure affects arthropod abundance and diversity. (C) 2004 Elsevier B.V. All rights reserved.
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| 2. |
- Jonsell, Mats, et al.
(författare)
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Saproxylic beetles in natural and man-made deciduous high stumps retained for conservation
- 2004
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Ingår i: Biological Conservation. - : Elsevier. - 0006-3207 .- 1873-2917. ; 118:2, s. 163-173
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Tidskriftsartikel (refereegranskat)abstract
- Intensive forest management in Scandinavia has decreased the amount of dead wood required by saproxylic (wood-living) organisms. To reduce this problem, some dead wood is now retained during forest operations, often in the form of man-made high stumps (ca. 4 m high). Most often these stumps are cut with a harvester, although the stumps in this study were made with explosives. The aims of this study were to determine whether such stumps of aspen (Populus tremula) and birch (Betula spp.) could be used by red-listed saproxylic beetles (Coleoptera), and to examine how the fauna of man-made high stumps differs from that of natural stumps. We also studied how tree species, sun-exposure, stage of decay and trunk diameter influenced the fauna. In 169 samples of bark from high stumps 116 saproxylic species were found, of which 21 were red-listed. Many species, including red-listed ones, were more associated with man-made stumps than with natural stumps. However, in total, more species were found in the natural than in the man-made stumps. This is probably because man-made stumps provide a more homogeneous type of wood substrate than natural ones. Among the other variables the difference between aspen and birch was the most important. We conclude that man-made high stumps are valuable habitats for many saproxylic beetle species.
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| 3. |
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| 4. |
- Nittérus, Karolina, 1972, et al.
(författare)
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Commercial harvest of logging residue in clear-cuts affects the diversity and community composition of ground beetles (Coleoptera : Carabidae)
- 2007
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 22:3, s. 231-240
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Tidskriftsartikel (refereegranskat)abstract
- Structural complexity of the habitat is known to influence the diversity and abundance of arthropod populations. Earlier studies have shown that presence of logging residue ( slash) on the ground contributes to microhabitat complexity and removal of slash for biofuel in clear-cuts can have short-term ( similar to 1 year) effects on ground-active beetle populations. This study examines the consequences of slash removal on carabids (Coleoptera: Carabidae) 5-7 years after harvest. Sampling of beetles was done by pitfall trapping in three matched clear-cut pairs, in spruce forest in central Sweden. The number and diversity (Berger-Parker dominance index) of carabid species were significantly higher in clear-cuts with slash harvest than in sites where slash was left on the ground. No difference in the overall rank-abundance pattern was found between clear-cuts with different slash treatments, but for species with certain habitat preferences the community was significantly altered. In all clear-cuts, slash removal caused a shift in dominance with an increase in generalist species and a decline in forest species. The results show that removal of slash may have long-lasting effects on the carabid community composition and structure. Hence, in forest landscapes with large-scale biofuel harvest, generalist carabid species may increase their abundance. Following the precautionary principle, it is suggested that every fifth clear-cut should be free of slash harvest.
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| 5. |
- Nittérus, Karolina, 1972, et al.
(författare)
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Effect of microhabitat complexity on the local distribution of arthropods in clear-cuts
- 2006
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Ingår i: Environmental Entomology. - 0046-225X. ; 35:5, s. 1324-1333
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Tidskriftsartikel (refereegranskat)abstract
- Structural complexity may affect activity and abundance of ground-dwelling arthropods. In this field experiment, the short-term effect on abundance of ground-active carabid beetles (Coleoptera: Carabidae) and lycosid spiders (Araneae: Lycosidae) from slash (logging residue) on the ground was studied. Arthropods were collected by pitfall trapping in three clear-cuts in southwest Sweden. The distribution of slash on the ground was manipulated, and two types of microhabitats were created adjacent to traps, i.e., either slash was cleared (bare ground traps) or slash was aggregated in heaps (slash-covered traps). Overall, carabids were significantly less abundant on the bare ground compared with the slash covered ground. For lycosids, no difference in abundance between the two microhabitat types was found. In reference plots, where no manipulation of microhabitat complexity was carried out, an overall positive relationship between structural complexity (slash height) and abundance of carabids was found. For lycosids, however, no correlations in reference plots were found. Bare ground microhabitats are mimicking structural complexity in clear-cuts after commercial slash harvest for biofuel. Large-scale removal of structural elements in clear-cuts might have short-term local effects, such as altered composition of arthropod communities.
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| 6. |
- Nittérus, Karolina, 1972, et al.
(författare)
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Insects reared from logging residue on clear-cuts
- 2004
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Ingår i: Entomologica Fennica. - 0785-8760. ; 15:1, s. 53-61
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Tidskriftsartikel (refereegranskat)abstract
- Coniferous and deciduous logging residue ("slash") was collected from six 1-year old and six 4-year old clear-cuts in South-West Sweden during the spring of 2002. In the laboratory, insects were emerged under standardised conditions. Insects emerged in 41% of the rearing-tubes with 1-year old slash. In 4-year old slash, 54% of the tubes contained insects. The most successfully emerged order was Coleoptera, represented by 10 families, 22 species and 425 individuals. The second most abundant order was Hymenoptera. The most abundant Coleoptera family was Curculionidae that comprised 48% of all the beetles. Four distinct species groups among Coleoptera. were found, each group being separated by slash age and tree category (deciduous/coniferous). Significantly more species were found in the 4-year old deciduous slash, compared to the 1-year old. In coniferous slash, there was a tendency for more species in the 1-year old slash than in the 4-year old. The results suggest that slash is valuable as breeding substrate and/or food supply to the beetle fauna on clear-cuts.
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| 7. |
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