| 1. |
- Lundström, Johanna, et al.
(författare)
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Cost-effective age structure and geographical distribution of boreal forest reserves
- 2011
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Ingår i: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 48, s. 133-142
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Tidskriftsartikel (refereegranskat)abstract
- P>1. Forest reserves are established to preserve biodiversity, and to maintain natural functions and processes. Today there is heightened focus on old-growth stages, with less attention given to early successional stages. The biodiversity potential of younger forests has been overlooked, and the cost-effectiveness of incorporating different age classes in reserve networks has not yet been studied.2. We performed a reserve selection analysis in boreal Sweden using the Swedish National Forest Inventory plots. Seventeen structural variables were used as biodiversity indicators, and the cost of protecting each plot as a reserve was assessed using the Heureka system. A goal programming approach was applied, which allowed inclusion of several objectives and avoided a situation in which common indicators affected the result more than rare ones. The model was limited either by budget or area.3. All biodiversity indicators were found in all age classes, with more than half having the highest values in ages >= 100 years. Several large-tree indicators and all deadwood indicators had higher values in forests 0-14 years than in forests 15-69 years.4. It was most cost-effective to protect a large proportion of young forests since they generally have a lower net present value compared to older forests, but still contain structures of importance for biodiversity. However, it was more area-effective to protect a large proportion of old forests since they have a higher biodiversity potential per area.5. The geographical distribution of reserves selected with the budget-constrained model was strongly biassed towards the north-western section of boreal Sweden, with a large proportion of young forest, whereas the area-constrained model focussed on the south-eastern section, with dominance by the oldest age class.6. Synthesis and applications. We show that young forests with large amounts of structures important to biodiversity such as dead wood and remnant trees are cheap and cost-efficient to protect. This suggests that reserve networks should incorporate sites with high habitat quality of different forest ages. Since young forests are generally neglected in conservation, our approach is of interest also to other forest biomes where biodiversity is adapted to disturbance regimes resulting in open, early successional stages.
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| 2. |
- Lundström, Johanna, et al.
(författare)
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Lichen species richness on retained aspens increases with time since clear-cutting
- 2013
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Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 293, s. 49-56
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Tidskriftsartikel (refereegranskat)abstract
- In modem forestry, attempts to mitigate negative effects on biodiversity include the integration of conservation actions into forestry activities, e.g. by leaving trees at harvesting. This practice has been used on a large scale for more than two decades without solid scientific support of whether desirable effects are achieved or not. To increase the knowledge of changes in the lichen flora on retained aspen trees (Populus tremula) with time since clear-cutting we made a study in boreal Sweden where 720 retained aspens in 24 stands were surveyed. Twelve stands were clear-felled 0-4 years and 12 where clear-felled 10-16 years prior to the inventory. Total lichen species richness increased with time since clear-cutting, as did richness of aspen-dependent lichens and lichens adapted to open environments. There was no difference between the age classes regarding the number of cyanolichens. We show that retained aspens function as lifeboats for old-forest lichens and as a new habitat for lichens adapted to open, sun-exposed habitats. Our results indicate that epiphytic species richness on retained trees is higher after the logging, due to coexistence of remaining species and colonizing species. We suggest that the retention of old aspen and the promotion of aspen generation in the production forest would benefit epiphytic lichens and are thus important conservation measures. (C) 2012 Elsevier B.V. All rights reserved.
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| 3. |
- Perhans, Karin, et al.
(författare)
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Co-variation of lichens, bryophytes, saproxylic beetles and dead wood in Swedish boreal forests
- 2010
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Ingår i: Systematics and Biodiversity. - : Informa UK Limited. - 1477-2000 .- 1478-0933. ; 8, s. 247-256
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Tidskriftsartikel (refereegranskat)abstract
- In order to effectively identify and protect the most valuable forest areas for conservation, it is essential to understand species diversity patterns and the co-variation of different taxonomic groups. In this study we analysed the extent to which lichens, bryophytes and saproxylic beetles co-vary, their ability to represent each other in a reserve network (surrogate capacity), and their patterns of beta-diversity. We also tested the surrogate capacity of dead wood. A species and dead wood inventory was conducted in forest sites in a boreal forest region in central Sweden. Overall, the correlations in species richness between taxa were weak, but some were statistically significant, i.e. those between red-listed lichens and red-listed bryophytes. Beetles were weakly positively correlated with bryophytes, but never with lichens. None of the tested taxa provided a reliable surrogate for representing the other taxa. However, dead wood diversity did represent saproxylic beetles and bryophytes better than random selection and might therefore function as a conservation surrogate for those taxa. Beta-diversity differed significantly between the taxa; lichens had the lowest, while beetles had the highest. Altogether beetles showed low association with the other taxa but high beta-diversity, which implies that they may require specific conservation planning.
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| 4. |
- Perhans, Karin, et al.
(författare)
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Fine-scale conservation planning outside of reserves: Cost-effective selection of retention patches at final harvest
- 2011
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Ingår i: Ecological Economics. - : Elsevier BV. - 0921-8009 .- 1873-6106. ; 70, s. 771-777
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Tidskriftsartikel (refereegranskat)abstract
- Retaining forest patches at final harvest is a key conservation measure in boreal forests, but guidelines for how to increase its cost-effectiveness are lacking. In a study in boreal Sweden, we compared the cost-effectiveness of three different approaches a forest owner may use to select patches: selection based on the conservation value of patches alone, economic cost alone or both of them combined. We also compared the cost-effectiveness of six different common types of patches. Conservation value was measured as species richness of bryophytes and lichens and as structural characteristics of patches. Compared to the selection approach in which both conservation value and cost were used, cost-effectiveness was 5-14% lower when only conservation value was used, depending on how conservation value was measured. On the contrary, using only the economic cost decreased the cost-effectiveness by only 1-2%. Among the patch types, swamp forest areas and deciduous tree groups were cost-effective types to retain. However, the patch types were complementary in their species composition and all hosted unique species. We argue that, ideally, assessments of both conservation values and economic costs of retaining patches should be made prior to harvest to enable planners to make well-informed and cost-effective decisions. (C) 2010 Elsevier B.V. All rights reserved.
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| 5. |
- Perhans, Karin, et al.
(författare)
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Retention patches as potential refugia for bryophytes and lichens in managed forest landscapes
- 2009
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Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 142, s. 1125-1133
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Tidskriftsartikel (refereegranskat)abstract
- Leaving small patches of forest intact at harvesting is now a standard procedure to mitigate negative effects on biodiversity. One purpose of the patches is to "life-boat" species over the forest regeneration phase, although the capacity of small forest fragments to do so is very uncertain. We investigated the survival of red-listed and indicator species of bryophytes and lichens in 74 retention patches in boreal Sweden. The patches were between 0.01 and 0.5 ha in size and of six different types with respect to tree species composition and location on the harvested area. Species presence and abundance were recorded shortly after harvest in transects covering the whole patches, and an identical inventory was carried out 6 years after the first. During this time, bryophytes generally decreased, most pronounced for liverworts. The largest decreases were found in buffer zones to streams and lakes and the smallest in tree groups dominated by deciduous trees. By contrast, among the lichens some species decreased while others increased, and there was no difference between retention patch types. Among the species abundant enough to be analyzed individually, the lichens Calicium parvum and Micarea globuloselia decreased less in larger patches and the bryophyte Hylocomiastrum umbratum decreased more in patches of irregular shape. The results imply that retention patches of this size might be too small to function as refugia for sensitive bryophytes and lichens until the surrounding forest regenerates, but that some lichens appear to persist or even increase. Retention harvesting is still a young management practice and further studies on its long-term conservation benefits will be valuable. (C) 2009 Elsevier Ltd. All rights reserved.
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| 6. |
- Perhans, Karin, et al.
(författare)
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The value of information in conservation planning: Selecting retention trees for lichen conservation
- 2014
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Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 318, s. 175-182
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Tidskriftsartikel (refereegranskat)abstract
- Conservation planning studies at small scales such as forest stands and below are uncommon. However, for retention forestry, developed during the last two decades and with current wide and increasing application in boreal and temperate regions, the need for cost-effective selection of individual trees is evident. In retention forestry certain trees are left at final harvest to promote flora and fauna. There is also a scarcity of studies on information costs and how these relate to the cost-effectiveness of conservation. We addressed both of these issues by studying whether decisions about the retention of aspen Populus tremula L. trees can be made more cost-effectively by including information about tree characteristics. We analyzed data from 12 recently harvested stands in middle Sweden containing 131 epiphytic lichen species (a biodiversity proxy) on 360 aspen trees. We related the presence of lichen species to bark and stem attributes and used those relationships to prioritize trees for retention. We estimated the value of using different sets of survey information (lichens, tree characteristics) to select retention trees to achieve various conservation goals. Depending on species or species groups of interest, and the type of tree information being collected, the value of collecting the information is up to 20% of the total value of all potential retention trees, which, given current labor costs, allows up to four hours for planning and selecting the right trees on an average-sized clearcut. The current practice of almost randomly selecting aspen trees to retain at final harvest can be improved by adding easily collected information on tree characteristics, such as black-colored bark, slow tree growth, inclining stems and speckled bark. This can lead to attainment of a given level of a conservation goal (like maximizing the number of lichen species of conservation concern) with fewer retention trees. Inventory of tree information often can be performed quickly, and if part of the gains from using such information to guide tree selection would be spent on additional conservation efforts, this would benefit biodiversity. Studies on more organism groups and tree species are needed to increase the applicability of results. (C) 2014 The Authors. Published by Elsevier B.V.
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| 7. |
- Wikberg, Sofie, et al.
(författare)
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Cost-effectiveness of conservation strategies implemented in boreal forests: The area selection process
- 2009
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Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 142, s. 614-624
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Tidskriftsartikel (refereegranskat)abstract
- To protect land from commercial exploitation is a common conservation practice. However, this requires large financial resources and it is therefore important to evaluate the cost-effectiveness of different strategies used in the selection of these conservation areas. In this study we compare four strategies and relate the differences in cost-effectiveness to differences in the selection process. We measure conservation benefits both as the amount of three tree structures and as the number of species in three species groups. We also estimate both the information cost associated with selecting conservation areas and the opportunity cost. we found the key habitat strategy to be the over-all most cost-effective. in this strategy, the areas have a flexible size and are selected by the authorities in a national field survey. The least cost-effective strategy was one where the selection was based only on forest classes in a satellite map. Intermediate were the retention group strategy, where small areas are left by the forest owner at harvesting, and the nature reserve strategy, where large areas are selected by the authorities. We emphasize that the differences we found are associated with the selection process and that other aspects, such as long-term survival of species, may rank the strategies differently. We conclude that the cost-effectiveness of a selection strategy depends on the size of the planning area for selection of conservation areas, the size of the conservation areas, the objective of the agent making the selection, and the amount and type of information on which the selection is based. (C) 2008 Elsevier Ltd. All rights reserved.
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