| 1. |
- Halme, P., et al.
(författare)
-
Challenges of ecological restoration : Lessons from forests in northern Europe
- 2013
-
Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 167, s. 248-256
-
Forskningsöversikt (refereegranskat)abstract
- The alarming rate of ecosystem degradation has raised the need for ecological restoration throughout different biomes and continents. North European forests may appear as one of the least vulnerable ecosystems from a global perspective, since forest cover is not rapidly decreasing and many ecosystem services remain at high level. However, extensive areas of northern forests are heavily exploited and have lost a major part of their biodiversity value. There is a strong requirement to restore these areas towards a more natural condition in order to meet the targets of the Convention on Biological Diversity. Several northern countries are now taking up this challenge by restoring forest biodiversity with increasing intensity. The ecology and biodiversity of boreal forests are relatively well understood making them a good model for restoration activities in many other forest ecosystems. Here we introduce northern forests as an ecosystem, discuss the historical and recent human impact and provide a brief status report on the ecological restoration projects and research already conducted there. Based on this discussion, we argue that before any restoration actions commence, the ecology of the target ecosystem should be established with the need for restoration carefully assessed and the outcome properly monitored. Finally, we identify the most important challenges that need to be solved in order to carry out efficient restoration with powerful and long-term positive impacts on biodiversity: coping with unpredictability, maintaining connectivity in time and space, assessment of functionality, management of conflicting interests and social restrictions and ensuring adequate funding. © 2013 Elsevier Ltd.
|
|
| 2. |
- Jonsell, Mats, et al.
(författare)
-
Structure of insect community in the fungus Inonotus radiatus in riparian boreal forests
- 2016
-
Ingår i: Journal of Natural History. - : Informa UK Limited. - 0022-2933 .- 1464-5262. ; 50, s. 1613-1631
-
Tidskriftsartikel (refereegranskat)abstract
- Basidiomes of polypore fungi host many insects. Yet systematic information about insect assemblages from most fungal species is lacking. We studied the insect community associated with the wood-decaying fungus Inonotus radiatus (Sowerby: Fr.) P. Karst. (Hymenochaetales). More specifically, we studied the effect of successional stage and weight of basidiomes, as well as shore exposition (north or south), on species richness and composition, as well as occurrence and abundance of the most abundant fungivores. Basidiomes were collected from riparian forests at five lakes in Sweden. Insects were reared out from the basidiomes in the laboratory. A total of 5645 adult insect individuals of 117 taxa were obtained. Among these, 2782 specimens of 36 taxa use Inonotus radiatus basidiomes as breeding habitat. Eight species of parasitic wasps were new to Sweden. The most abundant fungi- vore was Ennearthron cornutum (Ciidae), which is a generalist breeding in many polypore species. Based on our material and literature, the melandryid beetles Abdera affinis and A. flexuosa seem to be specialists on the order Hymenochaetales. Other fre- quent fungivores were Dorcatoma dresdensis (Ptinidae), and the lepidopterans Archinemapogon yildizae, Nemapogon cloacellus and N. picarellus (Tineidae). The parasitoid community associated with the tineid moths was similar to the community associated with the other polypore species in the order Polyporales. In contrast, the parasitoids associated with Dorcatoma (and/or Abdera) were dif- ferent from the other Polyporales species, suggesting that the fungal host species is more important for these parasitoid species than the beetle host species itself. The most abundant and fre- quent parasitoids were the braconids Diospilus dispar and Colastes fritzeni, which both parasitise Dorcatoma. Species richness was significantly smaller in fresh than in more decayed basidiomes, but species composition did not differ. There was no difference in species composition or richness between north and south shorelines.
|
|
| 3. |
- Komonen, Atte
(författare)
-
Conservation ecology of boreal polypores: A review
- 2011
-
Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 144, s. 11-20
-
Forskningsöversikt (refereegranskat)abstract
- Here we quantitatively summarize the conservation ecology of one group of dead-wood-dependent organisms, the polyporous fungi, in boreal Europe. At the substrate scale, the decay stage is the strongest determinant of species richness, with large (>20 cm diameter) downed logs hosting more species than other dead-wood types. At the stand scale, the amount of dead wood is the strongest determinant of poly-pore species richness; the minimum average amount of dead wood for the occurrence of rare polypores appears to be 20-40 m(3)/ha. Species-area analysis shows that in mature boreal forests species accumulation levels off at around 20-30 ha. This leads us to suggest a heuristic 20/20/20 rule of thumb: a 20 ha stand, with an average of 20 m(3)/ha of dead wood of which many are logs >20 cm, is likely to be the minimum for the ecologically justified conservation of polypore diversity at the stand scale in boreal Europe. Equally crucial for polypore diversity, however, is the current and historic extent of suitable habitats at the landscape scale. The time lag between the isolation of a habitat patch and the new equilibrium in the number or occurrence of species seems to be around 100-150 years, indicating that an extinction debt is likely to exist in recently isolated fragments. Only a few studies have addressed the ecological efficiency of the new, biodiversity-oriented forest management tools (retention trees, woodland key habitats). Despite this it seems that the traditional large conservation areas are the most effective means of polypore conservation. (C) 2010 Elsevier Ltd. All rights reserved.
|
|
| 4. |
- Komonen, Atte
(författare)
-
Forest characteristics and their variation along the lakeshore-upland ecotone
- 2009
-
Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 24, s. 515-526
-
Tidskriftsartikel (refereegranskat)abstract
- In forestry operations riparian buffer zones have been retained mainly to protect water quality. Because riparian forests are also important for maintaining terrestrial biodiversity, the associated ecotones need to be characterized and defined. Forest characteristics were studied along 50 m lakeshore-upland gradients in semi-natural forests in boreonemoral Sweden. Significant changes in the density of living and dead trees, as well as in their diameters, were recorded. The edge influence was generally discernible 10-30 m from the shoreline and was manifested in the very high density of understorey and midcanopy trees. The species-specific responses reflected the known shade and flooding tolerances of tree species. Most dead trees were standing, or broken from the roots or tree base; relatively few uprooted trees were recorded, suggesting that wind is only a moderate mortality factor. In comparison with the literature, the studied lakeshore forests are distinct from managed and set-aside upland forests in terms of tree species composition and woody debris characteristics; they thus contribute to landscape heterogeneity. If buffer zones along lakes were designed so that they captured the entire riparian ecotone, this would increase their contribution to the conservation of terrestrial biodiversity.
|
|
| 5. |
- Komonen, Atte, et al.
(författare)
-
Ips typographus population development after a severe storm in a nature reserve in southern Sweden
- 2011
-
Ingår i: Journal of Applied Entomology. - : Wiley. - 0931-2048 .- 1439-0418. ; 135, s. 132-141
-
Tidskriftsartikel (refereegranskat)abstract
- Large-scale natural disturbances pose challenges for the management of protected areas and may have undesirable consequences for commercial plantations nearby. A storm, which felled nearly 10 000 m3 of spruce forest in the Osaby nature reserve in southern Sweden, allowed us to study the subsequent population development of the spruce bark beetle (Ips typographus L.). Two summers after the storm, an exceptionally high proportion (74%) of wind-felled trees had been successfully colonized by the bark beetle, and all living spruce trees had been killed. On standing trees, colonization density was three times higher, and reproductive success one-fourth, that on wind-felled trees. The negative relationship between colonization density and reproductive success indicates that intra-specific competition is one of the main mechanisms reducing I. typographus population growth when the beetles switch from wind-felled to standing trees after storm disturbances. Indeed, there was no significant difference in beetle production between wind-felled and standing trees. Furthermore, there were no differences in colonization density, reproductive success or production at different heights in standing trees; however, a higher proportion of the new adults emerged at the tree-tops rather than lower down before overwintering. Our results also demonstrate that a large proportion (ca. 50%) of the I. typographus population that developed in the storm-fell area apparently overwintered under the bark of standing trees.
|
|
| 6. |
- Komonen, Atte
(författare)
-
Missing the rarest: is the positive interspecific abundance-distribution relationship a truly general macroecological pattern?
- 2009
-
Ingår i: Biology Letters. - : The Royal Society. - 1744-9561 .- 1744-957X. ; 5, s. 492-494
-
Tidskriftsartikel (refereegranskat)abstract
- Lepidopterists have long acknowledged that many uncommon butterfly species can be extremely abundant in suitable locations. If this is generally true, it contradicts the general macroecological pattern of the positive interspecific relationship between abundance and distribution, i.e. locally abundant species are often geographically more widespread than locally rare species. Indeed, a negative abundance-distribution relationship has been documented for butterflies in Finland. Here we show, using the Finnish butterflies as an example, that a positive abundance-distribution relationship results if the geographically restricted species are missed, as may be the case in studies based on random or restricted sampling protocols, or in studies that are conducted over small spatial scales. In our case, the abundance-distribution relationship becomes negative when approximately 70 per cent of the species are included. This observation suggests that the abundance distribution relationship may in fact not be linear over the entire range of distributions. This intriguing possibility combined with some taxonomic biases in the literature may undermine the generalization that for a given taxonomic assemblage there is a positive interspecific relationship between local abundance and regional distribution.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
