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This paper examines how the conflict over the management of the boreal forest of Quebec has been constructed through the documentary film l'Erreur boreale. It pays particular attention to the kind of discourses and practices used by the filmmakers to present the forest as a threatened entity. The paper shows that despite raising questions over the accessibility of the forest, the film promotes dominant industrial relationships with the forest which undermine other ways of imagining the relationships between forest users and the non-humans making up the forest. The paper suggests that the debate that resulted from the film offered few novel ideas to re-imagine relationships with the forest other than through the epistemic realm of forestry science and ecology. [ABSTRACT FROM AUTHOR]

Climate drives ecosystem processes and impacts biodiversity. Biodiversity patterns over large areas, such as Canada's boreal, can be monitored using indirect indicators derived from remotely sensed imagery. In this paper, we characterized the historical space–time relationships between climate and a suite of indirect indicators of biodiversity, known as the Dynamic Habitat Index (DHI) to identify where climate variability is co-occurring with changes in biodiversity indicators. We represented biodiversity using three indirect indicators generated from 1987 to 2007 National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer images. By quantifying and clustering temporal variability in climate data, we defined eight homogeneous climate variability zones, where we then analyzed the DHI. Results identified unique areas of change in climate, such as the Hudson Plains, that explain significant variations in DHI. Past variability in temperatures and growing season index had a strong influence on observed vegetation productivity and seasonality changes throughout Canada's boreal. Variation in precipitation, for most of the area, was not associated with DHI changes. The methodology presented here enables assessment of spatial–temporal relationships between biodiversity and climate variability and characterizes distinctive zones of variation that may be used for prioritization and planning to ensure long-term biodiversity conservation in Canada. [ABSTRACT FROM PUBLISHER]

Northern forested ecosystems are predicted to change dramatically in response to climate change during the next century. The purpose of this paper was to use logistic regression analysis to model the effects of climate and topography on the spatial distribution of the northern forest around Churchill, Manitoba, Canada. Climate maps were modeled using kriging interpolation of actual climate data collected from 34 long-term monitoring sites distributed throughout the study area, and topographic information was derived from commercially available digital elevation models. Five of the 18 independent variables contributed appreciably (p < 0.15) to the final logistic regression model: distance from the Hudson Bay coast, summer soil temperature, snow density, slope, and snow water equivalent. Current forest distribution was predicted with 66% accuracy using the final model, and Kappa statistics indicated significant agreement between modeled and actual forest extents. Significant explanatory variables demonstrate important synergistic effects of Hudson Bay, wind, and snow in determining forest distribution. Modeled forest extents were further south than actual forest limits, which suggest that the treeline is not likely in equilibrium with the present climate. [ABSTRACT FROM AUTHOR]

This paper reviews the doctoral thesis of Viktor Toivo Aaltonen, published in 1919. The study was the first, and to this date the only detailed ecological description of the structure and regeneration of natural Pinus sylvestris-dominated dry heath forests in northern Finland. The average density of Pinus seedlings was 8766 ha-1. In general, Calluna sites had the most seedlings, followed by Cladina sites, postfire areas and Empetrum sites. Seedling abundance and quality declined with decreasing site fertility and increasing canopy cover. The main limiting factor for regeneration was regarded to be not canopy cover (shading), but its correlate, the intensity of below-ground competition. The mostly small understorey seedlings (10-30 cm) were considered to be unable to grow into the dominant tree layer unless a gap had formed in this layer. Several examples of the asymmetric competition between large trees and seedlings were provided. These included the distance-dependent adverse influence of isolated trees as well as gap and forest edge environments on seedling number and size. Special microhabitats, such as logs and their surroundings as well as uprooting spots, were found to be favourable regeneration sites. A special regeneration microsite effect was demonstrated by groups of seedlings around isolated large canopy trees, termed Tapio's gardens by local people. The study illustrates how the small-scale spatial heterogeneity observed in unmanaged dry pine forests influences tree population dynamics, leading to a wide range of variability in stand structures and successional stages. The value of Aaltonen's study perhaps especially lies in the description of a relatively intact ecosystem type, whose ecological quality has recently declined to the extent of becoming classified as a nationally threatened habitat type. [ABSTRACT FROM AUTHOR]

This article is a review of a classic paper (1936) by the late Professor Rutger Sernander. This work by Sernander includes the very first formulations of a general theory about forest dynamics driven by storm fellings in fire refugia. Sernander discussed forest dynamics on three different scales: at the landscape, stand and individual tree scale. This article discusses all the important variables and the different stages in forest dynamics brought up by Sernander, such as different susceptibility to storm damage of stands growing on different soil types, the importance of different wind directions and speed, and differences between tree species with regard to susceptibility to wind. It also discusses differences in gap sizes and forms, decomposition degrees of fallen trees, different regeneration modes in connection with gap creation, the effects of wind disturbance on the field-layer vegetation and other stand characteristics, as observed by Sernander. [ABSTRACT FROM AUTHOR]

Forecasts of future resource states are central to resource management planning. Many simulation models and planning tools are used to produce such forecasts and apply knowledge of resource change dynamics as key input. Consistency among knowledge sources is therefore important to avoid knowledge ambiguity and uncertainty in resource forecasts and management plan outcomes. Using Ontario's boreal forest landscape as a case study, this paper examined two knowledge sources of forest resource change, practitioner expertise and research studies, commonly applied in plans and policies for large forest landscapes. The two knowledge sources were quantitatively compared by constructing networks of forest cover change for both sources and determining their agreement in structure and transition times. Some networks agreed well, indicating little knowledge ambiguity and comparatively low uncertainty if they were used to forecast forest landscapes. Other networks showed low agreement, thus indicating higher knowledge ambiguity and a dilemma of choice for forest landscape planners who may have to select from these knowledge sets. It is suggested that knowledge disagreements may be widespread in knowledge-driven management planning of many natural resource types and their causes similar. These disagreements signal areas of knowledge uncertainty, where resource planners must address resulting uncertainty of management outcomes and research should focus on improving resource change knowledge. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Permafrost mounds covered by open or dense forests (or krummholz - stunted trees) correspond to the category of wooded palsas and wooded peat plateaux extensively distributed in wetlands of North America. Very few data exist on the origin and development of wooded palsas, in particular their inception during the Holocene and the structure and dynamics of their forest/krummholz cover over time. Aim: The main objective of this paper is to fill the gap of knowledge on the origin and structure of wooded palsas, with a focus on wooded palsas located at their range limit at the treeline in eastern Canada. Methods: Each of the nine sites studied was surveyed along a line transect to measure the topography, to record the vegetation cover, to infer the snow thickness and to measure the thickness of the active layer at the time of sampling. The size structure of the black spruce (Picea mariana) populations of three dense wooded palsas was described. Basal stem discs of living and dead Picea were recovered for age determination, except in one site where only dead stems were sampled. The minimum age of wooded palsas at each site was evaluated based on tree-ring dating of the oldest stems and radiocarbon dating of the organic layers. Results: The inception of wooded palsas occurred during two principal periods of permafrost expansion as shown by the combined tree-ring and radiocarbon dates obtained for each of the nine studied sites. Three wooded palsas formed between 750 and 1000 AD, whereas the inception of the other palsas occurred during the 1500s. The up-thrusting of the wetland surface associated with permafrost growth facilitated tree establishment more intensively during the first period than during the second period when full Little Ice Age conditions prevailed in wind-exposed peatlands. Conclusions: The maintenance of a permafrost mound under forest cover is a rare situation in northern environments, and wooded palsas in eastern Canada form peculiar ecosystems where forest and permafrost coexist; these have survived over the last 500 to 1000 years. It is believed that the inception of wooded palsas was facilitated during a prolonged period of snow-poor winter conditions. Tree establishment was possible due to well-drained soil conditions associated with palsa up-thrusting. Although thicker snowpack preventing deeper frost penetration into the soil is maintained by the development of a forest/krummholz cover, wooded palsas at the treeline can survive because of low annual temperatures, reduced solar radiation beneath the tree canopy, variable accumulation and duration of annual snowpack. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Pathology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The James Bay Agreement reinforces the rights of the Crees to 500,000 km² of territory in the boreal forest and taiga of northern Quebec. In it, consultation and environmental assessment (EA) mechanisms were set up to ensure the Crees' direct involvement in environmental decisions. This paper addresses three matters: the influence of Native involvement in the EA process; updating the EA process under the Agreement to in-corporate the apparently new tools of strategic environmental assessments (SEAs); and adaptation of the concept of SEA to the Native context. Our analysis focuses on the experience gained from large hydroelectric development projects, recent and planned mining developments, and forestry operations. [ABSTRACT FROM AUTHOR]

Landscapes are created by people through their experience and engagement with the world around them and through their activities and movements on the ground. Human groups humanize an environment by mapping themselves onto the landscape using their knowledge of specific landforms and waterways, resources including minerals, plants and animals, and human settlements. Once established, this human imprint transforms the natural landscape into a cultural landscape and establishes a pattern of land use which can persist for generations, if not millennia. The objective of this paper is to examine and compare native perceptions and uses of landscapes using historic maps, established travel and trade routes, and ethnographic data on settlement locations for groups occupying the boreal forest and northwestern Plains of Canada. The data indicate that native perceptions of the landscape are rooted in the landforms and vegetation present in an area as well as the transportation technology available to the group. Although movement and vegetation influence the selection of landmarks on the landscape, mythology and oral traditions describe the origin and spiritual relationships of features on the landscape. [ABSTRACT FROM AUTHOR]

The microclimate of streamside habitats are protected from the effects of logging with buffer strips of retained trees. However, these buffer strips are often narrow due to their financial loss. Wider, selectively logged buffers might protect the microclimate while providing the same economic return. This study investigates the effects of logging on the microclimate and the growth of the bryophyte Hylocomium splendens on two streamside buffers: a standard unlogged narrow buffer (∼15 m) and a wider buffer (∼30 m) selectively logged with decreasing intensity towards the stream. The study was conducted in Central Finland on eight sites where the two buffers were logged next to each other. The near-stream change in air temperature and relative humidity was measured from pre-logging to post-logging. Additionally, post-logging microclimate gradients and the growth of H. splendens was measured on a 30 m transect away from the stream. The results showed no significant differences in the ability of the two kinds of buffers in maintaining streamside microclimate, and neither buffer seems to protect the microclimate from the negative effects of logging. The growth of H. splendens also decreased in both buffers. We conclude that wider, unlogged buffer strips are required to protect riparian forest microclimate. [ABSTRACT FROM AUTHOR]

This is a study about cultivated and 'wild' plants as components of the material heritage of crofters, an overlooked group of people in former agrarian landscapes. Despite abundant remains of crofts in Sweden, inhabited during the period from the eighteenth century until the 1940s, crofters have been subject to few studies. We used a survey conducted 1967 of botanical remains at abandoned croft as a basis for a re-survey in 2019. As with all biological traces of former human activities, cultivated plants and wild species favoured by former management ultimately disappear, but with long delays. We describe the patterns of this decline. In general, about a third of the species were gone after 52 years. The rate of disappearance of single species occurrences was about 1% annually. We discuss the interpretation of botanical remains from since long abandoned crofts in the context of heritage. In some cases, the botanical remains were the only material evidence left. We conclude that the material heritage of crofters deserves further studies and that botanical remains at abandoned crofts should be documented and at least at some sites protected. [ABSTRACT FROM AUTHOR]

Logging and forestry have traditionally been seen as a purely masculine sphere. The aim of this study is to analyze women's introduction into and situations in the forestry sector in twentieth century northern Sweden. We interviewed 30 women who worked as cooks between the 1930s and the 1960s, and examined written sources. We found that driving forces behind the emergence of a system involving forestry cooks included state investigations, rationalization of the forest sector, the effects of WW2, and overall modernization of society. Our informants were unmarried and young when they started working, and their introductions to the job were characterized by encouragement and pressure in their surroundings. They had prior knowledge of cooking, but few underwent formal training. They were, in most cases, hired by the forest workers, and portray the camps as egalitarian social systems. It is clear that the Swedish system was rather unusual internationally, and these women had a definite impact on modernizing a workspace far from cities and industries. For the women, the job entailed hardships, but also a sense of freedom. Conceivably, a seed of women's liberation in twentieth century Sweden was planted by these thousands of young women working in the northern forests. [ABSTRACT FROM AUTHOR]

Permafrost thawing could increase soil contaminant mobilization in the environment. Our objective was to quantify metal accumulation capacities for plant species and functional groups common to Alaskan military training ranges where elevated soil metal concentrations were likely to occur. Plant species across multiple military training range sites were collected. Metal content in shoots and roots was compared to soil metal concentrations to calculate bioconcentration and translocation factors. On average, grasses accumulated greater concentrations of Cr, Cu, Ni, Pb, Sb, and Zn relative to forbs or shrubs, and bioconcentrated greater concentrations of Ni and Pb. Shrubs bioconcentrated greater concentrations of Sb. Translocation to shoots was greatest among the forbs. Three native plants were identified as candidate species for use in metal phytostabilization applications. Elymus macrourus, a grass, bioconcentrated substantial concentrations of Cu, Pb, and Zn in roots with low translocation to shoots. Elaeagnus commutata, a shrub, bioconcentrated the greatest amounts of Sb, Ni, and Cr, with a low translocation factor. Solidago decumbens bioconcentrated the greatest amount of Sb among the forbs and translocated the least amount of metals. A combination of forb, shrub, and grass will likely enhance phytostabilization of heavy metals in interior Alaska soils through increased functional group diversity. [ABSTRACT FROM AUTHOR]

In the last decades a drastic increase in air temperature but a stable precipitation regime in Mongolia has led to gradual drying conditions. Thus, we evaluated the effect of spatial and climatic characteristics on the soil-plant nitrogen dynamics in three representative larch stands (Larix sibirica) with different geographical and climatic conditions using stable nitrogen isotopes. The results showed significant differences in the soil inorganic N content among sites and consequently a different isotopic composition in the plant-soil system. Litter, bark and wood had the lowest δ15N values for all sites, slightly higher δ15N values for needles, while the highest δ15N values were observed for roots and soil. These differences could be the result of the larch stands age themselves, but were in agreement with the spatial and climatic characteristics of the sites. Based on the δ15N value a higher reliance on ectomycorrhizal fungi (ECMF) was observed in the warmest and driest site, while lower dependency was shown in the cooler northern site with higher soil inorganic N content. In both sites, the rate of air temperature increase has been similar in the last decades; however, their soil-plant N dynamics showed different characteristics. [ABSTRACT FROM AUTHOR]

The vertical partitioning of fungi in forest soils regulates nutrient cycling. Chemical stress inhibits the organic matter turnover, and the role of fungal niche partitioning in this phenomenon needs exploration. Using next-generation sequencing, we studied fungal communities in organic and mineral soil horizons in control (unpolluted) and industrially polluted spruce-fir forests. Community composition and structure followed the pattern commonly observed in forest soils, with dominating ectomycorrhizal and saprotrophic mycelial fungi. In the control area, the ratio of ectomycorrhizal to saprotrophic fungal abundances was lower in the organic than in the mineral horizon. The strongest pollution-induced decrease of relative abundance and diversity was registered for saprotrophs, which are more exposed to heavy metals, and for those biotrophs, which lose most of their potential hosts. Therefore, the ratio of ectomycorrhizal to saprotrophic fungal abundances increased in the organic horizon in the polluted area, indicating a vertical repartition of fungal trophic guilds. [ABSTRACT FROM AUTHOR]

The article deals with various types of specially protected territories participating in preservation of biological diversity of boreal coniferous forests of the West Siberian Plain. Data are presented on species diversity of certain territories of Tomsk oblast established in various landscape and geographical conditions and under various conditions including areas within the Great Vasyugan Mire and the outskirts of Tomsk. The article reviews species of dominant plant families of rivers and lakes of the Polto system in the basin of the Tym river; and the condition of certain species of Orchidaceae, Empetraceae, Cupressaceae, Tiliaceae and Lamiaceae in other parts of the Tomsk region. There is also some analysis of species along with description of sites where 6 plant species were discovered (Orchis militaris,Orchis fuchsii,Juniperus communis,Empetrum nigrum,Tilia cordata,Stachys silvatica) that are protected in the area of study. [ABSTRACT FROM AUTHOR]

Historically, oak forests and woodlands intergraded with southern boreal forest, temperate mesic forest, and grassland biomes, forming complex fire-mediated relationships in the Great Lakes region of Minnesota, Wisconsin, and Michigan, USA. Variability in fire recurrence intervals allowed oaks to mix with grasses or with mesic forest species in areas with high (2–10 yr) or moderate (several decades) fire frequencies, respectively. In the southern boreal forest, oak colonization was limited by cold climate. In recent decades former savannas have been largely converted to agricultural fields and the fate of oak remnants is controlled by human fire use. In mesic temperate forests, fire exclusion, wetter climate, and deer browsing have led to mesophication and increasing maple dominance. With ongoing warming, however, mesophication could reverse due to increased drought and fire frequency, and earthworm invasion, which enhances the understory environment for oak seedlings. Oaks are also likely to invade large tracts of southern boreal forest. However, deer grazing on oak seedlings will partially negate the positive influence of warming and fire. On balance, oaks have a more positive future outlook in the Lake States, as the climate becomes more favorable to oaks compared to temperate mesic and boreal forests. [ABSTRACT FROM PUBLISHER]

The foliage biomass–sapwood relationship (the pipe model) is critical for tree growth and is used in tree growth models for understanding the implications of this structural relationship on the allocation of resources. In this research, we compared this relationship for two commercially important and sympatric species, black spruce (Picea mariana(Mill.) B.S.P.) and white spruce (Picea glauca(Moench) Voss). At locations in eastern Canada, 57 black and 50 white spruce trees were destructively sampled to obtain foliage biomass, crown structure, and tree stem measures. Using a model-based approach, we compared foliage biomass–branch basal area and foliage biomass–sapwood relationships at the tree and disk (i.e. along the tree stem) levels (i.e. pipe-model ratios) between these two species. We found that (i) branch foliage biomass–branch basal area was greater for black spruce than white spruce and (ii) pipe-model ratios along the tree stem given tree size were greater for black spruce than for white spruce. We attributed these differences to: (i) greater shade tolerance and leaf longevity of black spruce; (ii) slower growth rates of black spruce; and (iii) differing hydraulic strategies and mechanical requirements. [ABSTRACT FROM PUBLISHER]

Our objective was to automatically recognize the species composition of a boreal forest from high-resolution airborne winter imagery. The forest floor was covered by snow so that the contrast between the crowns and the background was maximized. The images were taken from a helicopter flying at low altitude so that fine details of the canopy structure could be distinguished. Segments created by an object-oriented image processing were used as a basis for a linear discriminant analysis, which aimed at separating the three dominant tree species occurring in the area: Scots pine, Norway spruce, and downy birch. In a cross validation, the classification showed an overall accuracy of 81.9%, and a kappa coefficient of 0.73. [ABSTRACT FROM AUTHOR]

The Late Pliocene (3.6–2.6 Ma) was a period of significant global warmth, considered a potential analogue for future anthropogenic climate change. Newly discovered fine-grained sediments from between the gold-bearing lower and upper White Channel Gravels show the presence of a wetland or lake within Bonanza Creek, Dawson Mining District, Yukon. This environment was surrounded by a diverse Pinaceae-dominated boreal forest with significant stands of angiosperms in favourable sites. Quantitative climate reconstructions derived from pollen and spores reveal a mean annual temperature at least 6 °C warmer than today with warm summers and relatively mild winters. Finally, the new pollen assemblage is used to discuss the age of the White Channel Gravels. [ABSTRACT FROM PUBLISHER]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Commercial thinning has recently been applied in the boreal forest of Quebec (Canada) to increase the volume growth of the residual trees. We aimed to discover if the growth response influences the transversal tracheid dimension of thinned black spruce (Picea mariana (Mill.) B.S.P.) and Jack pine (Pinus banksiana Lamb.) stands at 0.2 m stem height. All 20 studied stands have shown a significant growth response after the treatment (p<0.0001), especially trees with the lowest radial growth before thinning in comparison with the stand mean. Growing conditions met by suppressed trees before thinning might favour them in the competition for light, water and biomass production after the treatment. Trees with a positive growth response did not significantly modify their measured transversal tracheid dimension except for trees which increased twofold their ring-width after thinning. In this case, lumen area and radial cell diameter extended significantly. However individuals with a growth decrease after thinning registered significantly lower values in their ring width, earlywood and latewood cell numbers (p<0.0001) in both species. [ABSTRACT FROM AUTHOR]

Background: Spatial patterns within forests reflect their formative processes. In Kamchatka, the dominant stone birch (Betula ermanii) forest exists in a primeval state. Betula species can reproduce via clonally produced ramets, leading to a clustered distribution of stems, or from seed on open ground, although subsequent mortality may obscure initial establishment patterns. Methods: Spatial patterns of all trees and regenerating stems in a fully mapped 0.25 ha plot were analysed using the g(r) function and the pattern of trees modelled using a Matern cluster process. Mark correlation analysis was used to detect patterns in stem sizes. Results: Clustering of trees at scales up to 3 m occurred, with model parameters indicating a density of 180 clusters ha-1, each containing on average three stems >1 cm diameter at breast height (DBH) within a 1.6 m radius. Stem size compensation was detected, with nearby trees smaller than expected by chance. Regenerating stems were strongly clustered at scales below 3.5 m and from 5-8 m, and were aggregated around small trees (<10 cm DBH) but not large trees (≥10 cm DBH), or in gaps. Conclusions: These patterns are consistent with clonal reproduction followed by competition as the processes determining spatial structure in old-growth stone birch forests. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effects of dead wood on enchytraeids and nematodes were studied in thinned and uncut Norway spruce forests in two experiments. Fifteen pairs of small spruce logs (one enclosed in polyethylene sheet and another untreated control) were returned to the forest floor in a complete randomized block design after thinning. Soil under the logs and at distances of 0-6 cm and 6-12 cm from each log was sampled after one growing season, and enchytraeids and nematodes were extracted and forest floor properties measured. Log enclosure increased enchytraeid length irrespective of the distance from the log. Soil moisture or pH were not affected by enclosure, but organic matter content was reduced, suggesting that log enclosure indirectly enhanced organic matter decomposition and enchytraeid growth rate. Soil samples were taken beneath fallen large-diameter spruces and at three distances from tree trunks at one thinned and one uncut site. Enchytraeids were significantly smaller beneath the trunks than in the surrounding soil, although forest floor properties were similar at all distances from the trunk. It is possible that the enchytraeid size distribution reflects past rather than present forest floor properties. Nematode abundance was not affected by the distance from tree trunk or log enclosure. [ABSTRACT FROM AUTHOR]

According to the Kyoto Protocol, a Joint Implementation project is a mechanism whereby one industrialized country can finance a greenhouse gas-reducing project in another country. The investors in the project can, in return, claim credits for the reduction in carbon (C) emissions and carbon sequestration. The purpose of this case study was to investigate the potential for carbon sequestration from such projects. The study covers afforestation with Scots pine on unforested land (burnt areas, cleared spaces, gaps, etc.) in the Povolgie region of Russia. Three scenarios were compared: (1) no afforestation (baseline scenario); (2) afforestation with pine, and carbon sequestration only considering above-ground tree biomass; (3) afforestation with pine, but accounting for carbon sequestration in all pools. On average, carbon sequestration in the above-ground tree biomass could be around 80 t C ha-1 during 50 years of pine (Pinus sylvestris L.) plantation growth with 54 t C ha-1 in equilibrium storage. A considerable amount of carbon will be bound in the lower layer of the pine forest stand (24 t C ha-1), which is usually underestimated in afforestation Joint Implementation projects, and wood-based products (35 t C ha-1). Sequestered carbon in equilibrium storage is allocated in the following proportions: 46% in pine stands, 21% in the lower level and 33% in wood-based products. To extend the carbon sequestration, harvested wood should be used to manufacture products for long-term use. The results indicate good potential for such projects in the investigated territory in a long-term perspective, in compliance with international costs for sequestered carbon. [ABSTRACT FROM AUTHOR]

In a growth chamber experiment, root suckering of aspen (Populus tremuloides Michx.) was assessed in relation to timing of cutting and soil temperature. Aspen seedlings were grown in large pots for 3 years before experimentation. In a 2 × 2 factorial experiment, 3-year-old seedlings were cut at the end of the dormant period or after leaf flush and grown at two soil temperatures (8 or 20°C) for 39 days. Root systems were evaluated for suckering response and carbohydrate reserve status. There were no differences between the two soil temperatures and times of cut in the number of sucker buds initiated on the roots, but the number of buds that developed into suckers was much greater at 20°C. Cutting the dormant seedlings delayed suckering by nearly a week, resulting in smaller suckers at the time of harvest. However, cutting the seedlings when dormant produced almost twice the number of suckers than when cutting occurred after leaf-out. Total non-structural carbohydrates (TNC) of roots declined from 35.6% of dry weight at the end of the dormant season to 21.6% at the time of leaf-out, but there were no differences between the soil temperature and timing of cut treatments. After the 39 day growth period, root systems had 7% lower root TNC in the 20°C treatment than in the 8°C treatment, likely to support the development of the emerging suckers and higher respiration demands. [ABSTRACT FROM AUTHOR]

The coarse woody debris (CWD) was inventoried in two boreal Estonian conifer-dominated forest landscapes/national parks, Lahemaa and Karula, with different forestry history and management intensity. The inventoried areas in both national parks consisted of a core with a strict nature reserve (unmanaged) and the surrounding protected special and restricted management zones (management activities in the past). Stands with no records of silvicultural activity since the 1920s (unmanaged) were compared with traditionally harvested stands. CWD was measured as standing dead trees, logs and snags » 10 cm in diameter and » 1.3min length in 304 circular plots (Lahemaa 134 plots, Karula 170 plots; r =11.28 m, 400 m2. The volumes of CWD varied considerably between individual stands. The mean volume of CWD (standing and down combined) in Lahemaa was 48.5 m3 ha-1, ranging from 0.6 to 148.6 m3 ha-1. The mean volume of CWD in Karula was 27.6 m3 ha-1, ranging from 0.2 to 193.7 m3 ha-1 from stand to stand. On average, 19.5 m3 ha-1(40.2%) of CWD in Lahemaa was standing dead wood and 29.1 m3 ha-1 (59.8%) down dead wood. In Karula standing dead wood formed 15.2 m3 ha-1 (55.7%) and down dead wood 12.2 m3 ha-1 (44.3%). Variation in CWD volumes was clearly dependent on the management history of the stands. Stands with a documented history of management (e.g. cuttings and thinnings) had significantly lower CWD volume than natural stands found mainly in strict nature reserves. Stands selectively logged a long time ago (more than approximately 60 years) did not differ considerably from natural stands in the amount of CWD. The amount of CWD in managed stands (Lahemaa 14.1 m3 ha-1 and Karula 10.6 m3 ha-1) was comparable to other studies in silviculturally managed forests in the boreal zone. The study shows that CWD amounts in Estonian conditions are similar to previous studies in this region. [ABSTRACT FROM AUTHOR]

Abstract A pollen diagram from a small lake, Kutulahdenlampi, in northern Finland is interpreted in terms of the development of forest vegetation during the Holocene. The abundance of each of the forest taxa is considered independently by means of pollen accumulation rates (PARs), using as the reference material, long term average pollen deposition values monitored by a network of pollen traps. Particular attention is paid to the arrival of spruce and to the species in the original forests that this newcomer replaces. A model of pollen dispersal and deposition developed by Sugita is used to estimate the area around the lake that the pollen assemblage is most clearly reflecting. This relevant source area of pollen (RSAP), for the present day situations is c. 1,500 m. Pollen loadings calculated for a simulated landscape that mimics (i) that of the present day and (ii) for the situation at 8,000 BP (as deduced from the PARs) are compared with the pollen assemblages from the diagram at those points in time, and are seen to be compatible. The advantages of combining PAR and modelling to look at the spatial scale of vegetation reconstructions are discussed. [ABSTRACT FROM AUTHOR]

Through time primeval Europe was transformed into a landscape where managed woodlands (forestis) became repositories for resources and wild woods (silva) were seen as being occupied by wild men, the savages. The importation into the New World of these attitudes resulted in verdant North America being classified as 'wilderness'. It was generally assumed that the worlds of the past were essentially unaltered by hunter-gatherer activities. By the twentieth century, forest management practices in North America, supported by the myth of the primeval past, encouraged old growth forests through fire suppression. The fallacy of the unmanaged forest of prehistory is now being challenged. In its place are put forward models of forests as managed sustainers of a wide range of resources. In such models, fire is an essential management tool, not an ecodisaster. [ABSTRACT FROM AUTHOR]

The effects of forest management on the field layer vegetation were compared between Finnish and Russian Karelia in a total of 46 mature stands representing pine, spruce and deciduous forests. In Finland, the number of species was slightly higher in each forest type. Many grassland species, such as Galium boreale, Lathyrus pratensis, and Veronica officinalis, were more abundant in Finnish deciduous stands (14.4 species, mean cover 15.8%) than in Russian stands (9.6 species, mean cover 11.5%). Dwarf shrubs, such as Calluna vulgaris (mean cover: Fin 3.3%, Rus 7.7%) and Vaccinium vitis-idaea (Fin 25.0%, Rus 26.9%) in pine stands, and Vaccinium myrtillus (Fin 22.9%, Rus 31.5%) in spruce stands, were more abundant in Russia. Ferns and graminoids exhibited no differences between the two countries. The observed differences were likely to result from the lower tree stand density, more extensive fragmentation and fertilisation of forests in Finland, the higher frequency of forest fires and more intensive grazing in Russian forests, and from differences in natural conditions between Finnish and Russian Karelia. [ABSTRACT FROM AUTHOR]

An index of tree growth based on the mean growth curve of black spruce shows that tree growth in the boreal forest of central Canada decreases linearly as the forest-tundra boundary is approached. A theoretical tree line is defined by black spruce growth data. The distribution of tree growth and the theoretical tree line indicate that the forest-tundra boundary is the mean summer position of the arctic front. The growth of white spruce is briefly considered, but because of a small sample size, no conclusions are drawn. [ABSTRACT FROM AUTHOR]

Nine indicators of biodiversity conservation have been defined by the nations participating in the Montreal Process for assessing sustainability of temperate and boreal forests. Five of these indicators address compositional and spatial diversity of ecosystems; two address species diversity; and two are indirect measures of genetic diversity.Our objective was to evaluate their applicability for assessing biodiversity on rangeland ecosystems. In addition to assessing applicability, we also address whether data and methods exist to measure each indicator, and review research that is needed to improve implementation. In general, we found no ecological arguments for disqualifying anyof the proposed indicators as applicable to rangelands. We did find,however, that unambiguous definitions, data, and methods were woefully lacking. Although some data exist for some indicators and some taxa, none of the indicators can be quantified in a thorough and rigorous manner at a national scale. Consequently, initial assessments of biodiversity on rangelands will have to be based on incomplete data. Research in the areas of definition clarification, inventory design, and testing of critical assumptions is necessary to conduct comprehensive, broad-scale assessments of biodiversity. [ABSTRACT FROM AUTHOR]