Showing papers in "Canadian Journal of Forest Research in 2002"
TL;DR: A method for predictive vegetation mapping that applies direct gradient analysis and nearest-neighbor imputation to ascribe detailed ground at- tributes of vegetation to each pixel in a digital landscape map is presented.
Abstract: Spatially explicit information on the species composition and structure of forest vegetation is needed at broad spatial scales for natural resource policy analysis and ecological research. We prese...
538 citations
TL;DR: In this paper, a search for the minimum time for fire to travel among nodes in a two-dimensional network is considered, and the paths that produce the minimum travel time are chosen.
Abstract: Fire-growth modeling on complex landscapes can be approached as a search for the minimum time for fire to travel among nodes in a two-dimensional network. The paths producing minimum travel time be...
329 citations
TL;DR: Under global change, the severity of these stressors may increase, which would pose a serious concern for the future health, productivity, and carbon sequestration of aspen forests in the region.
Abstract: Trembling aspen (Populus tremuloides Michx.) is the most important deciduous tree in the Canadian boreal forest, with >1000 Tg of carbon stored in the aboveground biomass of this species. Since the early 1990s, aspen dieback has been noted over parts of the southern boreal forest and aspen parkland in western Canada. In this study, tree-ring analysis and forest health assessments were conducted in 18 aspen stands near Grande Prairie, Alta., to exam - ine causes of reduced growth and dieback. Defoliation histories were reconstructed based on light-colored ("white") tree rings and records of past insect outbreaks. The results indicated that several factors contributed to the observed dieback. Defoliation by forest tent caterpillar ( Malacosoma disstria Hbn.) and drought in the 1960s and 1980s led to reduced growth and predisposed some stands to secondary damage by wood-boring insects and fungal pathogens. Thaw-freeze events during a period (1984-1993) of unusually light snow cover in late winter may have also contrib- uted to the observed dieback. Under global change, the severity of these stressors may increase, which would pose a serious concern for the future health, productivity, and carbon sequestration of aspen forests in the region. Resume : Avec plus de 1000 Tg de carbone emmagasine dans la biomasse epigee de cette essence, le peuplier faux- tremble (Populus tremuloides Michx.) est l'espece decidue la plus importante dans la foret boreale canadienne. Depuis le debut des annees 1990, le deperissement du peuplier faux-tremble a ete note dans certaines parties de la foret bo- reale meridionale et les tremblaies de l'ouest du Canada. Dans cette etude, l'analyse des cernes annuels et l'evaluation de l'etat de sante de la foret ont ete realisees dans 18 peuplements de peuplier faux-tremble, pres de Grande Prairie en Alberta, afin d'examiner les causes de la reduction de croissance et du deperissement. L'historique des defoliations a ete reconstitue sur la base des cernes de couleur pâle (« blanc ») et des donnees sur les epidemies d'insectes passees. Les resultats montrent que plusieurs facteurs ont contribue au deperissement qui a ete observe. La defoliation par la livree des forets (Malacosoma disstria Hbn.) et la secheresse survenues au cours des annees 1960 et 1980 ont entraine une reduction de croissance et predispose certains peuplements aux attaques des insectes xylophages et des pathogenes fongiques. Des episodes de degel et gel lors d'une periode (1984-1993) ou la couverture de neige etait exceptionnelle- ment mince a la fin de l'hiver peuvent egalement avoir contribue au deperissement. Dans le contexte d'un rechauffe- ment global, la severite de ces stress pourrait augmenter, ce qui causerait une grande inquietude dans l'avenir pour la sante et la productivite des forets de peuplier faux-tremble dans la region et la sequestration du carbone par ces forets.
301 citations
TL;DR: The effects of litter quality and climate on decomposition rates of plant tissues were examined using percent mass remaining (MR) data of 10 foliar litter types and 1 wood type during 6 years exposure at 18 upland forest sites across Canada.
Abstract: The effects of litter quality and climate on decomposition rates of plant tissues were examined using percent mass remaining (MR) data of 10 foliar litter types and 1 wood type during 6 years expos...
300 citations
TL;DR: Moisture in gaps declined over multiple years, likely caused by encroachment of vegetation within and around gaps, but the variety of microenvironments in large gaps may facilitate diverse plant communities.
Abstract: The effects of gap formation on solar radiation, soil and air temperature, and soil moisture were studied in mature coniferous forests of the Pacific Northwest, U.S.A. Measurements were taken over ...
297 citations
TL;DR: In this article, allometric equations were developed relating aboveground biomass, coarse root biomass, and sapwood area to stem diameter at 17 study sites located in the boreal forests near Thompson, Man.
Abstract: Allometric equations were developed relating aboveground biomass, coarse root biomass, and sapwood area to stem diameter at 17 study sites located in the boreal forests near Thompson, Man. The six ...
248 citations
TL;DR: Simulations indicate partial harvest and minimal fire use may provide as many forest products as the traditional clearcut - broadcast-burn system while increas- ing C stores, and an adequate supply of wood products may not be incompatible with a system that increases C stores.
Abstract: We used a new model, STANDCARB, to examine effects of various treatments on carbon (C) pools in the Pacific Northwest forest sector. Simulation experiments, with five replicates of each treatment, ...
216 citations
TL;DR: Duff characteristic data were collected from two burns and comparable unburned areas of mixedwood forest in western Canada to describe and explain patterns of duff consumption within and between top-slope Pinus banksiana Lamb.
Abstract: Postfire tree recruitment in the boreal forest is restricted to patches from which the duff (organic layer) has been removed by fire. Duff consumption occurs by smoldering combustion, propagation of which is determined by bulk density, moisture content, and depth. This study investigated interactions among these factors, their spatial distribution, and spatial patterns of duff consumption in two wildfires. A hypothesized positive relationship between moisture content and depth was supported by a laboratory study. Duff characteristic data were collected from two burns and comparable unburned areas of mixedwood forest in western Canada to describe and explain patterns of duff consumption within and between top-slope Pinus banksiana Lamb. Picea mariana (Mill.) BSP stands and lower slope pure stands of Picea mariana on glaciofluvial hillslopes. In unburned stands, bulk density did not differ significantly between stands, while depths were significantly greater in Picea stands. With moist duff, consumption w...
199 citations
TL;DR: The ability of rare disturbances to increase heteroge- neity of forest structure and composition in this ecosystem, especially through interactions with other disturbances, is illustrated.
Abstract: A major ice storm in January 1998 provided an opportunity to study the effects of a rare, intense distur- bance on the structure of the northern hardwood forest canopy. Canopy damage was assessed using visual damage classes within watersheds of different ages at the Hubbard Brook Experimental Forest (HBEF) and changes in leaf area index in two of these watersheds. Ice thickness was measured, and ice loads of trees were estimated using regression equations. In the 60- to 120-year-old forests (mean basal area 26 m 2 ·ha -1 ), damage was greatest in trees >30 cm diam- eter at breast height and at elevations above 600 m. Of the dominant tree species, beech (Fagus grandifolia Ehrh.) was the most damaged, sugar maple (Acer saccharum Marsh.) was the most resistant, and yellow birch (Betula alleghaniensis Britt.) was intermediate. Trees with advanced beech bark disease experienced heavier ice damage. Little damage occurred in the 14-year-old forest, while the 24- to 28-year-old forest experienced intense damage. In the young stands of this forest, damage was greatest between 600 and 750 m, in trees on steep slopes and near streams, and among pin cherry (Prunus pensylvanica L.). Recovery of the canopy was tracked over three growing seasons, and root growth was monitored 1 year after the storm. Because of the high density of advance regeneration from beech bark disease and root sprouting potential in ice-damaged beech, HBEF will likely see an increase in beech abundance in older forests as a result of the storm. There will also be a more rapid change from pioneer species to mature north- ern hardwoods in the younger forests. These predictions illustrate the ability of rare disturbances to increase heteroge- neity of forest structure and composition in this ecosystem, especially through interactions with other disturbances. Resume : En janvier 1998, une importante tempete de verglas a fourni une occasion d'etudier les effets d'une perturba- tion rare et severe sur la structure du couvert dans une foret de feuillus nordiques. Les dommages subis par le couvert ont ete evalues visuellement a l'aide de classes de dommages dans des bassins d'âge different situes a la foret experi-
169 citations
TL;DR: In this paper, the authors analyzed three years (1996-1998) of eddy-covariance carbon dioxide flux measurements from two contrasting deciduous forest ecosystems in the boreal and temperate regions of central Canada.
Abstract: Boreal and temperate deciduous forests at northern mid-latitudes play an important role in the global carbon cycle. We analyze 3 years (1996-1998) of eddy-covariance carbon dioxide flux measurements from two contrasting deciduous forest ecosystems in the boreal and temperate regions of central Canada. The two forest stands have similar ages, heights, and leaf area indices but differ in species composition and climate. Mean annual net ecosystem produc- tivity (NEP) was similar for the two ecosystems, varying between 0.7 and 2.7 t C·ha -1 (boreal) and 0.6 and 2.4 t C·ha -1 (temperate). In the boreal ecosystem, interannual differences in NEP were primarily controlled by early spring tempera - ture. The warm spring of 1998 caused early leaf out and increased photosynthesis but had little effect on respiration. In the temperate ecosystem, the same warm spring not only caused early leaf out but also increased respiration and drought stress. The contrasting impact of the warm spring on annual NEP at the two sites illustrates the complexity of interpreting climatic impacts on the forest carbon balance. It also illustrates two competing influences of climate change on NEP: spring warming, which promotes photosynthesis and increases NEP, and increased soil temperature and drought, which promote respiration and reduce photosynthesis, thus reducing NEP. We discuss the need for a con- sistent data post-processing methodology in ecosystem intercomparisons. We also compare our results with a recent synthesis of data from European forests. Resume : Les forets decidues temperees et boreales situees dans la partie nord des latitudes moyennes jouent un role important dans le cycle global du carbone. Nous avons analyse trois annees (1996-1998) de mesures de flux de dioxyde de carbone effectuees avec la methode des correlations turbulentes dans deux ecosystemes forestiers decidus contrastes des regions temperees et boreales du centre du Canada. Les deux peuplements forestiers ont un âge, une hauteur et un indice de surface foliaire similaires mais different par leur composition en especes et par le climat. La
162 citations
TL;DR: Both harvesting treatments increased the volume and biomass of non-decayed, small-diameter CWD, with the 20% treatment showing a greater increase than the 10% treatment and both treatments showing greater increases than the control.
Abstract: We examined the dynamics of down coarse woody debris (CWD) under an expanding-gap harvesting system in the Acadian forest of Maine. Gap harvesting treatments included 20% basal area removal, 10% ba...
TL;DR: The independent error term was necessary with the individual tree additive genetic model to avoid substantial positive bias in estimates of additive genetic variance in the AR1 model and ...
Abstract: Spatial analysis, using separable autoregressive processes of residuals, is increasingly used in agricultural variety yield trial analysis. Interpretation of the sample variogram has become a tool for the detection of global trend and "extraneous" variation aligned with trial rows and columns. We applied this methodology to five selected forest genetic trials using an individual tree additive genetic model. We compared the base design model with post-blocking, a first-order autoregressive model of residuals (AR1), that model with an independent error term (AR1η), a combined base and autoregressive model, an autoregressive model only within replicates and an autoregressive model applied at the plot level. Post-blocking gave substantial improvements in log-likelihood over the base model, but the AR1η model was even better. The independent error term was necessary with the individual tree additive genetic model to avoid substantial positive bias in estimates of additive genetic variance in the AR1 model and ...
TL;DR: Within a single genus, both eastern and western tree species showed the same overall acclimation to light and height, and Pinus species showed less variation in growth and morphological responses to light than Abies and Picea species.
Abstract: The effects of gradients in light levels and tree height on growth and crown attributes of six conifer species were studied in eastern and western Canada. Three conifers were studied in British Columbia (Abies lasiocarpa (Hook.) Nutt., Picea glauca (Moench) Voss x Picea engelmannii Parry ex Engelm., and Pinus contorta Dougl. ex Loud. var. latifolia Engelm.), and three in Quebec (Abies balsamea (L.) Mill., Picea glauca, and Pinus banksiana Lamb.). For several growth and morphological parameters, conifers reacted strongly to both an increase in light and tree height. Significant or nearly significant interactions between light classes and height were found for height and diameter growth of most species as well as for many crown attributes for both Abies and Picea. These interactions usually indicated that growth or morphological changes occurred with increasing height from a certain light level. Within a single genus, both eastern and western tree species showed the same overall acclimation to light and height. As generally reported, Pinus species showed less variation in growth and morphological responses to light than Abies and Picea species.
TL;DR: In this article, the authors studied regional variation in growth-limiting factors and responses to climatic variability in subalpine forests by analyzing growth patterns for 28 tree-ring growth chronologies from sub-pine forests.
Abstract: We studied regional variation in growth-limiting factors and responses to climatic variability in subalpine forests by analyzing growth patterns for 28 tree-ring growth chronologies from subalpine ...
TL;DR: In this paper, the response of net ecosystem productivity and evaporation in a boreal aspen (Populus tremuloides Michx.) forest and a black spruce (Picea mariana (Mill.) BSP) forest in Canada was compared.
Abstract: The response of net ecosystem productivity (NEP) and evaporation in a boreal aspen (Populus tremuloides Michx.) forest and a black spruce (Picea mariana (Mill.) BSP) forest in Canada was compared u...
TL;DR: The feasibility and efficiency of predicting cellulose content using near infrared reflectance (NIR) analysis was examined for Eucalyptus globulus Labill, and calibrations indicated that NIR analysis could be used as a reliable predictor.
Abstract: Determining kraft pulp yield in the traditional way is slow and expensive, limiting the numbers of samples that may be processed. An alternative is to use a secondary standard, such as cellulose content of the wood, which is strongly correlated with kraft pulp yield. The feasibility and efficiency of predicting cellulose content using near infrared reflectance (NIR) analysis was examined for Eucalyptus globulus Labill. Calibrations for NIR prediction of cellulose content indicated that NIR analysis could be used as a reliable predictor. Standard errors of calibration were 1% or lower, and there was excellent agreement between laboratory and predicted cellulose values. Cellulose content was under moderate genetic control (h2 ranging from 0.32 to 0.57), and genetic correlations with tree diameter and basic density were variable (ranging from 0.11 to 0.51 and 0.33 to 0.67, respectively). The advantages, disadvantages, and potential applications of NIR analysis for predicting cellulose content are examined.
TL;DR: In this paper, the authors studied old Pinus sylvestris L. dominated forests in three geographic regions in the middle boreal vegetation zone: (i) in Hame in southwestern Finland, characteriz...
Abstract: Coarse woody debris (CWD) was studied in old Pinus sylvestris L. dominated forests in three geographic regions in the middle boreal vegetation zone: (i) in Hame in southwestern Finland, characteriz...
TL;DR: It is demonstrated that mineral soil, thin Polytrichum Hedw.
Abstract: We studied the post-wildfire establishment of jack pine (Pinus banksiana Lamb.), black spruce (Picea mariana (Mill.) BSP), and white spruce (Picea glauca (Moench) Voss) in the southern mixedwood boreal forest of Saskatchewan, Canada. The major objective of the study was to determine the influence of post-wildfire seedbed types on the juvenile survivorship of trees. Through a combination of permanent plots and sowing experiments, we demonstrated that mineral soil, thin Polytrichum Hedw. moss, and humus are much more favorable than the organic fermentation (Of) and litter seedbeds. We also show that differences among seedbeds are significantly more important than differences among species. In addition, the first year of a cohort has the highest rate of mortality, about 85% on mineral and humus seedbeds and 98% on Of seedbeds; differences in age-specific survivorship between seedbeds become muted by the end of the second year, and survivorship rates approach 1 by the end of the third summer. Finally, age str...
TL;DR: This work examined fine root turnover using both the minirhizotron and radiocarbon methods within the organic horizon of a northern hardwood forest to better understand discrepancies in turnover estimates.
Abstract: We examined fine root turnover using both the minirhizotron and radiocarbon methods within the organic horizon of a northern hardwood forest to better understand discrepancies in turnover estimates...
TL;DR: A close relationship was found between the wood density and fibre properties, especially with the proportion of cell wall in a cross section in a nutrient optimization experiment in northern Sweden.
Abstract: The effect of fertilization on wood density, fibre length, fibre diameter, lumen diameter, proportion of cell wall area, and cell wall thickness of Norway spruce (Picea abies (L.) Karst.) were stud...
TL;DR: The zone-specific all-factor model for application, which explained 82% of the variation of site index and provided unbiased and precise predictions, is recommended for application.
Abstract: To evaluate the variation in trembling aspen (Populus tremuloides Michx.) productivity at a large geographic scale, we examined the relationships between site index and environmental factors from 1...
TL;DR: Time series of seed production and tree-ring width of Norway spruce (Picea abies (L.) Karst.
Abstract: Time series of seed production and tree-ring width of Norway spruce (Picea abies (L.) Karst.) in southern Norway were analysed for their relationship to various climatic factors occurring during "k...
TL;DR: To estimate the age of Norway spruce logs by means of decay classes, and to assess how long it takes for downed logs to decompose, logs were dated dendrochronologically by a number of methods.
Abstract: To estimate the age of Norway spruce (Picea abies (L.) Karst.) logs by means of decay classes, and to assess how long it takes for downed logs to decompose, we dated logs dendrochronologically by a...
TL;DR: Post-fire timber harvesting (salvage logging) is becoming more prevalent as logging companies try to recover some of the economic losses caused by fire.
Abstract: Post-fire timber harvesting (salvage logging) is becoming more prevalent as logging companies try to recover some of the economic losses caused by fire. Because salvaging is a relatively new practi...
TL;DR: The data suggest that decomposing fine roots could release at least 20 kg N/ha annually in mature Douglas- fir forests of the Pacific Northwest, and initial N concentration and soil N availability were not correlated with fine-root decomposition rates.
Abstract: We examined the effects of species, initial substrate quality, and site differences (including temperature, pre - cipitation, and soil N availability) on fine-root (<2 mm diameter) decomposition in litter bags and its N dynamics in Sitka spruce (Picea sitchensis (Bong) Carriere), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) forests in Oregon, U.S.A. Species significantly influenced fine-root mass loss during the first 2 years of decomposition. Over the same period, site differences had little impact on decom - position of fine roots. The percentage of initial mass remaining of decomposing fine roots fitted a single-exponential model. The decomposition rate constant (k) for all 15 species examined ranged from 0.172 year -1 for Engelmann spruce (Picea engelmanni Parry ex Engelm.) to 0.386 year -1 for Oregon ash (Fraxinus latifolia Benth.). Initial C qual- ity indices (e.g., cellulose concentration, lignin concentration) of fine roots were correlated with fine-root decomposi - tion rates. In contrast, initial N concentration and soil N availability were not correlated with fine-root decomposition rates. The rate of N released from decomposing roots was positively correlated with the initial N concentration of the fine roots. The data suggest that decomposing fine roots could release at least 20 kg N/ha annually in mature Douglas- fir forests of the Pacific Northwest. Resume : Nous avons etudie les effets dus a l'espece, a la qualite initiale du substrat et aux differences entre les sites (incluant la temperature, la precipitation et la disponibilite de N dans le sol) sur la decomposition des racines fines (<2 mm de diametre) en sacs de litiere et la dynamique de N dans des forets d'epinette de Sitka (Picea sitchensis (Bong.) Carriere), de douglas de Menzies (Pseudotsuga menziesii (Mirb.) Franco) et de pin ponderosa (Pinus ponderosa Dougl. ex P. & C. Laws.) en Oregon, aux Etats-Unis. L'espece influence significativement la perte de masse des raci- nes fines pendant les deux premieres annees de decomposition. Pendant la meme periode, les differences entre les sites ont eu peu d'impact sur la decomposition des racines fines. Ce qui restait de la masse initiale suite a la decomposition des racines fines suit une courbe exponentielle unique. La constante du taux de decomposition (k) pour l'ensemble des 15 especes etudiees varie de 0,172 an -1 pour l'epinette d'Engelmann (Picea engelmannii Parry ex Engelm.) a 0,386 an -1 pour le frene de l'Oregon (Fraxinus latifolia Benth.). Les indices de qualite du C initial (p. ex., concentration de cellu- lose et de lignine) des racines fines sont correles aux taux de decomposition des racines fines. Au contraire, la concen- tration initiale de N et la disponibilite de N dans le sol ne sont pas correlees aux taux de decomposition des racines fines. Le taux de liberation de N provenant de la decomposition des racines fines est positivement correle a la concen - tration initiale de N dans les racines fines. Les donnees indiquent que la decomposition des racines fines pourrait libe - rer au moins 20 kg N/ha annuellement dans les forets matures de douglas de Menzies dans la region du Pacifique Nord-Ouest. (Traduit par la Redaction) Chen et al. 331
TL;DR: In this paper, the authors presented methods to generate fuel type maps from remote sensing data at a spatial and temporal scale adequate for operational fire management applications, using a fuel type classification system adapted to the ecological characteristics of the European Mediterranean basin.
Abstract: This paper presents methods to generate fuel type maps from remote sensing data at a spatial and temporal scale adequate for operational fire management applications. Fuel type maps account for structural characteristics of vegetation related to fire behaviour and fire propagation. A fuel type classification system adapted to the ecological characteristics of the European Mediterranean basin was adopted for this study. The Cabaneros National Park (in cen- tral Spain) area was selected for testing and validating the methods. Fuel type maps were derived from two Landsat TM satellite images and digital elevation data. Atmospheric and topographic corrections of the satellite images were performed to reduce spectral variability. A sensitivity analysis was carried out to determine the most appropriate bands for fuel type mapping. The final classification was checked by an intense field survey, the final classification accuracy being estimated at 83%. The main problem was discriminating among those fuel types that differ only in vegetation height or composition of the understory layer. The mean mapping accuracy was 15 m (0.6 pixels), and no areal dis- crepancy or boundary displacement with vegetation maps was apparent. Resume : Cet article presente des methodes pour generer des cartes de types de combustible a partir de donnees de te- ledetection a des echelles spatiale et temporelle adequates pour etre utilisees dans la gestion operationnelle des feux. Les cartes de types de combustible tiennent compte des caracteristiques structurales de la vegetation en lien avec le comportement et la propagation du feu. Un systeme de classification des types de combustible adapte aux caracteristi- ques ecologiques du bassin de la Mediterannee europeenne a ete adopte pour cette etude. La region du parc national Cabaneros (dans le centre de l'Espagne) a ete choisie pour tester et valider les methodes. Les cartes de types de com- bustible ont ete produites a partir de deux images satellitaires Landstat capteur TM et de donnees digitales d'altitude. Les images satellitaires ont ete corrigees pour tenir compte des conditions atmospheriques et topographiques afin de re- duire la variabilite spectrale. Une analyse de sensibilite a ete effectuee pour determiner quelles bandes sont les plus ap- propriees pour cartographier les types de combustible. La classification finale a ete verifiee par un inventaire intensif sur le terrain et sa precision a ete estimee a 83 %. La principale difficulte consiste a distinguer les types de combus - tible qui different seulement par la hauteur ou la composition de la vegetation de sous-etage. La precision moyenne de la cartographie est de 15 m (0,6 pixels) et aucune divergence dans la superficie ni modification des contours ne sont apparentes comparativement aux cartes de vegetation.
TL;DR: Pollen and charcoal from East Sooke Fen, Pixie Lake, and Whyac Lake were used to reconstruct the post glacial vegetation, climate, and fire-disturbance history across a precipitation gradient on so...
Abstract: Pollen and charcoal from East Sooke Fen, Pixie Lake, and Whyac Lake were used to reconstruct the post glacial vegetation, climate, and fire-disturbance history across a precipitation gradient on so...
TL;DR: In this paper, the export of microbially produced nitrate from an ecosystem is expected to increase δ15N in the remaining soil organic matter and NH4+ in the USA.
Abstract: Export of microbially produced nitrate from an ecosystem is expected to increase δ15N in the remaining soil organic matter and NH4+. To test the hypothesis that nitrification and nitrate loss induc...
TL;DR: The effect of fire on soil climate was most pronounced in P. mariana stands, which experienced a mean seasonal temperature increase of 58°C in the upper 1 m of the soil profile, a 200% increase in the rate of active layer thaw, and ...
Abstract: Boreal forests contain large amounts of stored soil carbon and are susceptible to periodic disturbance by wildfire. This study evaluates the relationship between post-fire changes in soil temperature, moisture, and CO2 exchange in paired burned and control stands of three Alaskan forest systems: Picea mariana (Mill.) BSP, Picea glauca (Moench) Voss, and Populus tremuloides Michx. In these systems, the environmental factor that most directly controlled rates of carbon exchange varied depending upon burn status and soil drainage. In mature unburned stands, CO2 flux was highly correlated with seasonal patterns of soil temperature. Following fire, these soils became significantly warmer, and carbon exchange became more sensitive to fluctuations in surface moisture conditions. The effect of fire on soil climate was most pronounced in the P. mariana stands, which experienced a mean seasonal temperature increase of 58°C in the upper 1 m of the soil profile, a 200% increase in the rate of active layer thaw, and ...
TL;DR: Since species compo- sition varied with time since the last fire, it is important to preserve the diversity of successional stages at the land - scape level and the structural diversity at the stand level to maintain the bryophyte and lichen communities.
Abstract: We sampled 22 black spruce (Picea mariana) - feathermoss (Pleurozium schreberi) sites (80 to >200 years) to describe and assess the diversity of bryophyte and lichen communities as a function of ti...