Substrate quality regulates density loss, cellulose degradation and nitrogen dynamics in downed woody debris in a boreal forest

Managed coniferous forest dominates much of the black-backed woodpecker’s ( Picoides arcticus Swainson) breeding range. Despite this, little is known about the fine-scale foraging behaviour of this focal species in unburned managed forest stands in the absence of insect outbreaks. To investigate the foraging substrates used in such a habitat, we employed radio-telemetry to track a total of 27 black-backed woodpeckers. During two successive summers (2005–2006), 279 foraging observations were recorded, most of which were on dying trees, snags, and downed woody debris. Individuals frequently foraged by excavation, suggesting that in the absence of insect outbreaks the black-backed woodpecker forages mainly by drilling. The majority of foraging events occurred on recently dead snags with a mean dbh (±SE) of 18.3 ± 0.4 cm. Our results suggest that in unburned boreal forest stands, substrate diameter and decay class are important predictors of suitable foraging substrates for black-backed woodpeckers. We suggest that conservation efforts aimed at maintaining this dead-wood dependent cavity nesting species within the landscape, should endeavour to maintain 100 ha patches of old-growth coniferous forest. This would ensure the continuous production of a sufficient quantity of recently dead or dying trees to meet the foraging needs of this species.

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Post-fire recovery of ecosystem carbon pools in a tropical mixed pine-hardwood forest

Forest Systems ◽

10.5424/fs/2020291-14984 ◽

2020 ◽

Vol 29 (1) ◽

pp. e001

Author(s):

Shatya Devi Quintero-Gradilla ◽

Angelina Martínez-Yrizar ◽

Felipe Gracía-Oliva ◽

Ramón Cuevas-Guzmán ◽

José Enrique Jardel-Peláez

Keyword(s):

Woody Debris ◽

Mineral Soil ◽

Biosphere Reserve ◽

Hardwood Forest ◽

Carbon Pools ◽

Research Station ◽

C Storage ◽

Ecosystem Carbon ◽

Sierra De Manantlán ◽

Downed Woody Debris

Aim of the study: To analyze the recovery pattern of carbon pools in terms of size and the relative contribution of each pool to total ecosystem C along a fire chronosequence of tropical mixed pine-hardwood forest.Area of the study: Las Joyas Research Station (LJRS), core zone of Sierra de Manantlán Biosphere Reserve (SMBR) in the state of Jalisco, central western Mexico.Materials and methods: Carbon stored in aboveground plant biomass, standing dead trees, downed woody debris, forest floor, fine roots and mineral soil, was compared with a nested analysis of variance (ANOVA) in post-fire stands of eight-year-old, 28- and 60-year-old stands of mixed Pinus douglasiana-hardwood forest.Main results: The total ecosystem carbon in eight-year-old stands was 50% lower than that of 60-year-old stands. Carbon content in the biomass and mineral soil increased with stand age. The carbon in the biomass recovered to the undisturbed forest in the 28 years of succession. The main C storage in the eight-year-old stands were the mineral soil (64%) and downed woody debris (18%), while in the 28- and 60-year-old stands, live tree biomass and mineral soil were the two largest components of the total C pool (43% and 46%, respectively).Research highlights: We found a significant effect of high-severity fire events on ecosystem C storage and a shift in carbon distribution. The relatively fast recovery of C in ecosystem biomass suggests that mixed Pinus douglasiana hardwood forest possess functional traits that confer resilience to severe ﬁre events.Key words: chronosequence; carbon dynamics; mineral soil; Pinus douglasiana; fire effects.Abbreviations used: LJRS, Las Joyas Research Station; DBH, diameter at breast height; DL, duff layer; LL, litter layer; DWD, downed woody debris; ANOVA, analysis of variance; CO2, carbon dioxide; SMBR, Sierra de Manantlán Biosphere Reserve; C, carbon. AGV, above ground vegetation.

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Epixylic vegetation abundance, diversity, and composition vary with coarse woody debris decay class and substrate species in boreal forest

Canadian Journal of Forest Research ◽

10.1139/cjfr-2017-0283 ◽

2018 ◽

Vol 48 (4) ◽

pp. 399-411 ◽

Cited By ~ 7

Author(s):

Praveen Kumar ◽

Han Y.H. Chen ◽

Sean C. Thomas ◽

Chander Shahi

Keyword(s):

Species Richness ◽

Species Diversity ◽

Boreal Forest ◽

Plant Communities ◽

Coarse Woody Debris ◽

Woody Debris ◽

Percent Cover ◽

Diverse Range ◽

Decay Class ◽

Wide Range

Although the importance of coarse woody debris (CWD) to understory species diversity has been recognized, the combined effects of CWD decay and substrate species on abundance and species diversity of epixylic vegetation have received little attention. We sampled a wide range of CWD substrate species and decay classes, as well as forest floors in fire-origin boreal forest stands. Percent cover, species richness, and evenness of epixylic vegetation differed significantly with both CWD decay class and substrate species. Trends in cover, species richness, and evenness differed significantly between nonvascular and vascular taxa. Cover, species richness, and species evenness of nonvascular species were higher on CWD, whereas those of vascular plants were higher on the forest floor. Epixylic species composition also varied significantly with stand ages, overstory compositions, decay classes, substrate species, and their interactions. Our findings highlight strong interactive influences of decay class and substrate species on epixylic plant communities and suggest that conservation of epixylic diversity would require forest managers to maintain a diverse range of CWD decay classes and substrate species. Because stand development and overstory compositions influence CWD decay classes and substrate species, as well as colonization time and environmental conditions in the understory, our results indicate that managed boreal landscapes should consist of a mosaic of different successional stages and a broad suite of overstory types to support diverse understory plant communities.

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Essais de jardinage sans martelage dans des peuplements irréguliers de sapin baumier et d’épinette noire

The Forestry Chronicle ◽

10.5558/tfc86498-4 ◽

2010 ◽

Vol 86 (4) ◽

pp. 498-510 ◽

Cited By ~ 3

Author(s):

Jérôme Cimon-Morin ◽

Jean-Claude Ruel ◽

Marcel Darveau ◽

Jean-Martin Lussier ◽

Philippe Meek ◽

...

Keyword(s):

Black Spruce ◽

Woody Debris ◽

Abies Balsamea ◽

Basal Area ◽

Shannon Index ◽

Simplified Approach ◽

Selection Cutting ◽

Quadratic Mean Diameter ◽

Downed Woody Debris ◽

Index Tree

It is increasingly accepted that silviculture must now try to maintain complex stands. In this context, selection cutting has been suggested as an option for irregular boreal stands. However, selection cutting in virgin stands could prove difficult to apply at a reasonable cost. In an attempt to reduce harvesting costs, two selection cutting patterns were implemented, avoiding tree marking. The efficacy of this approach was evaluated by comparing the results of plots harvested without tree marking to those with tree marking. To proceed in the absence of tree marking, silvicultural types were defined as well as a rule for the selection of stems to harvest; the final choice of stems to fell was therefore left to the operator upon harvesting. The effects of the different silvicultural and tree marking treatments were examined in relation to their ability to maintain the main structural and functional attributes of irregular boreal stands. A follow-up was conducted with regards to structure, composition, residual stand basal area, abundance of woody debris and mortality. The absence of marking did not affect the performance of selection cutting treatments in terms of basal area, quadratic mean diameter and Shannon index. Tree vigour was not modified by harvesting, both with and without tree marking. Stand composition was not influenced by the absence of marking. Snag abundance was reduced to similar levels regardless of marking. Tree marking did not influence the abundance of downed woody debris. As a consequence, it seems possible to apply a simplified approach of selection cutting, without compromising the success of the treatment in these stands.Key words: black spruce, Picea mariana, balsam fir, Abies balsamea, irregular stand, selection cutting, ecosystem management, forest attributes

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Biomass Harvesting Guidelines affect downed woody debris retention

Biomass and Bioenergy ◽

10.1016/j.biombioe.2014.08.010 ◽

2014 ◽

Vol 70 ◽

pp. 382-391 ◽

Cited By ~ 24

Author(s):

S.R. Fritts ◽

C.E. Moorman ◽

D.W. Hazel ◽

B.D. Jackson

Keyword(s):

Woody Debris ◽

Biomass Harvesting ◽

Downed Woody Debris

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Fire severity as a determinant factor of the decomposition rate of fire-killed black spruce in the northern boreal forest

Canadian Journal of Forest Research ◽

10.1139/x10-218 ◽

2011 ◽

Vol 41 (2) ◽

pp. 370-379 ◽

Cited By ~ 16

Author(s):

Yan Boulanger ◽

Luc Sirois ◽

Christian Hébert

Keyword(s):

Moisture Content ◽

Boreal Forest ◽

Decomposition Rate ◽

Black Spruce ◽

Woody Debris ◽

Fire Severity ◽

Decomposition Process ◽

Vertical Position ◽

Decomposition Rates ◽

Considerable Impact

Several attributes might influence the decomposition process of fire-killed trees. Here, we tested various tree- and plot-level variables on the decomposition rate of fire-killed black spruce ( Picea mariana (Mill.) BSP) in the northern boreal forest. Data were collected from 474 individuals burned 17 years prior to sampling. Mean decomposition rate was relatively slow (k = 0.013) and was lowest for severely burned snags (k = 0.001) and highest for lightly burned logs (k = 0.027–0.036). Vertical position and fire severity were the most important variables influencing the decomposition rates, while plot-level variables were marginally significant. Both predictors strongly influenced the moisture content of fire-killed trees. Logs with greater contact with the ground and lightly burned trees had higher moisture content and faster decomposition rates. Very severely burned trees had lower moisture content because of faster bark shedding. This hampered the decomposition process by slowing the snag falling rate. Higher decomposition rates in lightly burned trees may result from greater colonization by early xylophagous species. By having a considerable impact on the decomposition of woody debris, fire severity may strongly influence many post-fire biological processes related to the woody necromass as well as carbon emission from burned stands.

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Decomposition of woody debris in Western Australian forests

Canadian Journal of Forest Research ◽

10.1139/x26-105 ◽

1996 ◽

Vol 26 (6) ◽

pp. 954-966 ◽

Cited By ~ 57

Author(s):

Sandra Brown ◽

Jiangming Mo ◽

James K. McPherson ◽

David T. Bell

Keyword(s):

Moisture Content ◽

Cold Water ◽

Woody Debris ◽

Water Soluble ◽

Nutrient Concentrations ◽

Substrate Quality ◽

Clear Cut ◽

Moisture Regimes ◽

Sclerophyll Forest ◽

Decomposition Coefficient

Changes in mass and nutrients in experimental logs of six tree species during 5 years of exposure in the three major forest production regions of southwest Western Australia were measured to determine how climate, substrate quality, and substrate size interact to regulate decomposition of woody debris in this Mediterranean-type climate. Branch (3–5 cm in diameter) and bole (10–15 cm in diameter) material of the six species was set out in representative areas of a regenerating clear-cut Eucalyptusdiversicolor F. Muell. wet sclerophyll forest, selectively cut Eucalyptusmarginata Donn ex Smith dry sclerophyll forest, and clear-cut areas of a former Pinuspinaster Aiton plantation. Experimental logs were collected at about 0.5, 2, and 5 years after placement and were separated into bark and wood components. Samples of initial material were analyzed for moisture content, water-soluble and NaOH-soluble extractives, and nutrient concentrations (N, P, K, Ca, and Mg). At each collection, moisture content and changes in mass and nutrient concentration were determined for the sample logs. Eucalyptuscalophylla R.Br, the major associate of the two native forests, lost the most mass during this time, up to 65% of the initial mass (decomposition coefficient k = 0.22 year−1). Decomposition was least in P. pinaster and E. marginata, at about 24–26% of original mass (k = 0.05 year−1 and 0.07 year−1, respectively). Mass losses were greatest in Manjimup, the wettest site, and least at Gnangara, the driest site, but differences in overall levels of decomposition were small despite the range in climatic moisture regimes. Small logs decomposed faster than large logs. Changes in nutrient concentrations occurred in all logs at all sites, indicating activity by decomposer organisms and (or) leaching losses. Nitrogen was the only element to be immobilized over the 5-year period. Mineralization rates were of the order P ≈ Ca < Mg < K. Concentrations of compounds extractable in cold water and NaOH decreased during the 5 years of exposure. Differences in decomposition rates were partly explained by initial concentrations of N only; there appeared to be no relationship between decomposition and concentration of the other elements and extractives.

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Interactions between Hillslope Hydrochemistry, Nitrogen Dynamics, and Plants in Fennoscandian Boreal Forest

Global Biogeochemical Cycles in the Climate System ◽

10.1016/b978-012631260-7/50019-4 ◽

2001 ◽

pp. 227-233 ◽

Cited By ~ 9

Author(s):

Peter Högberg

Keyword(s):

Boreal Forest ◽

Nitrogen Dynamics

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Contrasting downed woody debris dynamics in managed and unmanaged northern hardwood stands

Canadian Journal of Forest Research ◽

10.1139/x08-130 ◽

2008 ◽

Vol 38 (11) ◽

pp. 2850-2861 ◽

Cited By ~ 28

Author(s):

Mark C. Vanderwel ◽

Hilary C. Thorpe ◽

Jennifer L. Shuter ◽

John P. Caspersen ◽

Sean C. Thomas

Keyword(s):

Matrix Model ◽

Woody Debris ◽

Fruiting Bodies ◽

Northern Hardwood ◽

Decay Class ◽

Species Type ◽

Downed Woody Debris ◽

Cut Surface ◽

Selection Silviculture

The reported effects of selection silviculture on downed woody debris (DWD) vary. To investigate the processes underlying potential management impacts on DWD stocks and fluxes, we conducted a repeated census of downed wood in selection-harvested, selectively harvested, and unmanaged (old-growth) stands in central Ontario. DWD was significantly more abundant in stands harvested within the last 20 years than in stands harvested earlier, and shifted towards more advanced decay classes over the first 20 years after harvest. These results are consistent with persistence of a harvest-related DWD pulse for up to two decades in managed stands. The transition of DWD from early and middle decay classes to more advanced decay classes proceeded more slowly in managed than unmanaged stands. Species type, identity of fungal fruiting bodies, presence of a cut surface, and plot moisture class were significant predictors of variation in decay dynamics within particular decay classes; however, these factors did not account for observed differences in decay-class transitions between managed and unmanaged stands. A decay class matrix model projected DWD half-lives of 19 years for unmanaged stands and 21 years for managed stands. Over the long term, slower decay dynamics may help somewhat in maintaining relatively high DWD abundances in stands managed under selection silviculture.

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