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Cavities made by birds are an important microhabitat for many taxa in forests. Long-term dynamics of cavity patterns and the effect of forest management on cavities are, however, largely unknown. We studied cavity production, measured as nest cavity production rates (CPR = no. of new cavities/km2/year), of woodpeckers and tits in forests with different management intensity in southern Finland, based on a data from 37 years. Forests were divided into managed, seminatural and natural stands. The data covered 56 forest stands with the total area of 1690 ha. Stands were inventoried annually for new cavities. The total numbers of woodpecker and tit cavities were 2238 and 329, respectively. There were large differences in CPRs between forest stands with different management intensity. For woodpeckers, the CPR was highest in natural forests (5.7) and lowest in managed forests (1.5). For the tit species, the respective numbers were 0.9 and 0.3. The CPRs of different cavity-making bird species and cavity tree characteristics (e.g. tree condition and species) were consistent, suggesting that different cavity-makers benefit from similar forest and tree characteristics. The results also suggest that forests managed with currently prevailing methods limit the production of cavities. To promote cavities, the results from this and other studies suggest that managed forests should include more features of natural forests, such as more diverse tree species and within-stand structural variability distribution (tree-level heterogeneity), larger amount of decayed wood, more retention trees and snags and longer rotation periods. [ABSTRACT FROM AUTHOR]

The rotation forestry system provides high biomass production, but could also have a negative impact on species sensitive to disturbance. Continuous cover forestry (CCF) could contribute to solving these conflicting goals, but its feasibility in nutrient limited boreal forests is yet unresolved. In a unique experiment, we simultaneously assessed the short-term effect of single-tree selection on both biomass production and biodiversity (vascular plants, bryophytes, wood-inhabiting fungi), and tested fertilization as a way to mediate growth-biodiversity trade-offs. We found that unharvested stands and stands subjected to single-tree selection had a similar species assemblage of vascular plants, bryophytes, and wood-inhabiting fungi. Fertilization increased growth by 37% and induced shifts in two understory species (favoring the grass Avenella flexuosa and disfavoring the bryophyte Hylocomium splendens). We conclude that single-tree selection may become a useful tool to enhance biodiversity in managed forests. [ABSTRACT FROM AUTHOR]

Intensive management of boreal forests has replaced natural disturbances, leading to losses of residual deadwood and saproxylic biodiversity. Declining population sizes have been well documented for insect groups such as bark and wood-boring beetles, whilst other groups such as flat bugs (Heteroptera: Aradidae) are less well-studied and little is known about their response to forest restoration. We conducted two restoration experiments addressing this lack of knowledge. We predicted the following responses to restoration: (1) artificial gap-creation and prescribed burning will attract more flat bugs than control stands, (2) increasing pre-burning fuel loads will have a positive influence on flat bug response to fire restoration. To test these predictions we conducted two field experiments; in Sweden we compared prescribed burning of standing forest with artificial gap-creation and in Finland we compared differing levels of fuel-load prior to burning. We found partial support for our first prediction, total numbers of flat bugs collected was higher in burned forest stands compared to controls in both countries. By contrast, gap-cutting only resulted in a marginal increase in the numbers and species of flat bugs collected. We found no support for our second hypothesis. The red-listed Aradus angularis and A. laeviusculus were primarily found in burned stands. Aradus betulae, A. betulinus and A. lugubris were more frequent in burned stands than gap-cuttings and untreated controls. Our study therefore suggests that ecological restoration, especially burning, is an efficient way of attracting flat bugs to suitable habitat, we therefore recommend ecological restoration to be incorporated in boreal forest management. [ABSTRACT FROM AUTHOR]

Assessing ecological sustainability involves monitoring of indicators and comparison of their states with performance targets that are deemed sustainable. First, a normative model was developed centered on evidence-based knowledge about (a) forest composition, structure, and function at multiple scales, and (b) performance targets derived by quantifying the habitat amount in naturally dynamic forests, and as required for presence of populations of specialized focal species. Second, we compared the Forest Stewardship Council (FSC) certification standards' ecological indicators from 1998 and 2010 in Sweden to the normative model using a Specific, Measurable, Accurate, Realistic, and Timebound (SMART) indicator approach. Indicator variables and targets for riparian and aquatic ecosystems were clearly under-represented compared to terrestrial ones. FSC's ecological indicators expanded over time from composition and structure towards function, and from finer to coarser spatial scales. However, SMART indicators were few. Moreover, they poorly reflected quantitative evidence-based knowledge, a consequence of the fact that forest certification mirrors the outcome of a complex social negotiation process. [ABSTRACT FROM AUTHOR]

Boreal flat bugs include a high proportion of species that are considered negatively affected by forestry. Knowledge on the biology and habitat demands of individual species is generally limited. We examined the influence on flat bugs of stand-age and clear-cutting, comparing five classes of spruce stands. The five classes were: clear-cut, unthinned, and thinned (all three products of current clear-cutting forestry), mature managed and old-growth stands (these two had never been clear-cut). We also compared unburned and recently burned mature pine forest. Fire, but not stand age, had a pronounced effect on species richness and total abundance. Aradus depressus showed a significant association with older forest stands. Aradus betulae occurred only in clear-cuts and burned forest indicating that this species is favored by disturbance in general. Aradus lugubris, Aradus crenaticollis and Aradus brevicollis were found only in the burned forest. Aradus brevicollis has not previously been shown to be associated with fire. [ABSTRACT FROM AUTHOR]

Fire is important in maintaining a diversity of communities and landscapes in boreal ecosystems, but, in recent times, forest management has suppressed fires. Managers now commonly burn a proportion of clear-cuts in Sweden to conserve components of the fire-favoured fauna, but effects of these treatments on the ant fauna are unknown. We compared ant communities between burned and control clear-cuts to determine their value for this important faunal group. Ants were collected in 1995 and 1996 from 5 burned and 5 control clear-cuts in mid-boreal Sweden. We compared abundances of workers and reproductive females of common species between the treatments. Burned and control clear-cuts supported similar abundances of common species, differing only in the abundance of Leptothorax acervorum queens collected in 1995. This suggests that L. acervorum was attracted to the burning, but we did not detect an increase in the abundance of its workers the following year. The abundance of dominant red wood ants ( F. rufa group) was not correlated with that of any other species, suggesting that their patchy occurrence did not conceal differences between treatments. Our findings suggest that nests of many ant species survive low severity fires. Habitat structure is likely to be important in determining ant community structure and low severity burning in disturbed open habitats, such as the clear-cuts examined in this study, may not significantly alter habitat structure relative to unburned habitats in the short term. [ABSTRACT FROM AUTHOR]