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- Bell, David, et al.
(författare)
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Forest restoration to attract a putative umbrella species, the white-backed woodpecker, benefited saproxylic beetles
- 2015
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Ingår i: Ecosphere. - 2150-8925 .- 2150-8925. ; 6:12
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Tidskriftsartikel (refereegranskat)abstract
- Umbrella species are often spatially demanding and have limited ability to adapt to environmental changes induced by human land-use. This makes them vulnerable to human encroachment. In Sweden, broadleaved trees are disadvantaged by forestry, and commercially managed forests are often deprived of dead wood. This has led to a situation where previously widespread top predators in saproxylic food webs, such as the white-backed woodpecker (Dendrocopos leucotos), have become species of conservation concern. The white-backed woodpecker is generally considered an umbrella species, and it has been linked to forests with large volumes of dead wood from broadleaved trees. In recent years, forest stands have been restored for the white-backed woodpecker, but post-treatment evaluations have rarely included other species that also occur in broad-leaved forests (co-occurring species). Many co-occurring species are saproxylic beetles. In this study, we collected saproxylic beetles and environmental data in restored and commercially managed forests to evaluate if habitat restoration for the white-backed woodpecker also benefited other species with similar habitat associations. We found that volumes of coarse woody debris were higher in restored than in commercially managed forests, and that a majority of man-made snags and downed logs were created from birch trees (Betula spp.). Most spruce trees (Picea abies) were extracted during forest restoration, and this opened up the forest canopy, and created stands dominated by broadleaved trees. Many saproxylic beetles were more common in restored forests, and there were significant differences in species composition between treatments. These differences were largely explained by species traits. Effects of sun-exposure were particularly important, but many beneficiary species were also linked to dead wood from broadleaved trees. Red-listed saproxylic beetles showed a similar pattern with more species and individuals in restored sites. The white-backed woodpecker is still critically endangered in Sweden, but important prey species are already responding to forest restoration at the stand level. We recognize that landscape-level improvements will be required to bring the white-backed woodpecker back, but also that the umbrella species concept can provide a useful framework for successful forest restoration as many co-occurring saproxylic beetle species seemingly benefitted from restoration for the white-backed woodpecker.
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| 2. |
- Berglund, Christer, et al.
(författare)
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A note on inter-country differences in waste paper recovery and utilization
- 2002
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Ingår i: Resources, Conservation and Recycling. - 0921-3449 .- 1879-0658. ; 34:3, s. 175-191
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Tidskriftsartikel (refereegranskat)abstract
- Countries worldwide express waste paper recycling targets in terms of recovery and utilization rates. The main purpose of this paper is to identify and analyze the most important determinants of inter-country differences in these waste paper rates. By employing two regression models and using data for 89 and 81 countries, respectively, the paper concludes that relative waste paper recovery and use are largely market-determined, and depend thus on long-standing economic factors such as population intensity and competitiveness in the world market for paper and board products. We also find evidence that supports the conjecture that rich countries tend to recover relatively more waste paper than is the case in low-income countries, reflecting the higher demand for waste management and environmental policies in more developed economies. As recovery and utilization rates are determined largely by long-standing economic and demographic characteristics the degree of policy flexibility in affecting these rates may be limited. In particular, an ambitious utilization rate target may be very costly to enforce as it can conflict with existing trade patterns of paper and board products as well as with other environmental goals. Additional policy targets may, therefore, be desirable, especially since paper recycling is motivated primarily by environmental concerns and seldom is a benign activity in itself.
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| 3. |
- Berglund, Christer, et al.
(författare)
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Evaluating new institutional settings : a pilot study of new common property forest in Tanzania
- 1999
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Ingår i: Scandinavian Journal of Development Alternatives. - 0280-2791. ; 18:1, s. 43-54
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study is to evaluate the creation of institutions concerned with common forests in an economy in transition, Tanzania. The paper uses a framework developed by Ostrom [1990]. Focusing on successful community-oriented, organized irrigation networks Ostrom defines eight design principles. These eight principles are tools that can be used in evaluating common pool resource systems. The initial experiences of the two villages Duru and Ayasanda help to illustrate how the common forests of the villages will work in the future. In evaluating these forests, using Ostrom's framework, the paper finds that most of the fundamental requirements are fulfilled.
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