The effects of experimental forestry treatments on site conditions: short response study from an oak-hornbeam forest

Background Forest management alters the forest site, however, information is still limited about how different silvicultural treatments modify these conditions. In the past decades, besides rotation forestry, new silvicultural systems were introduced, fulfilling the requirements of multipurpose forestry. In this study we investigated the short-term effects of different forestry treatments on microclimate, litter and soil conditions in a European oak-dominated forest. Methods A forest ecological experiment was established in a homogenous, managed, 80 years old, Quercus petraea and Carpinus betulus dominated forest, in 2014. Five treatments of three different forestry systems were installed following a complete block design in six replicates: clear-cutting with a circular retention tree group as typical elements of the clear-cutting system, preparation cutting (partial harvest) belonging to the shelterwood system, gap-cutting as a common tool of continuous cover forestry in Europe and uncut control. Microclimate, litter and soil variables were measured systematically since 2014. Here we present the results of the analyses of the first growing season following the interventions (2015). Results We found that there is strong treatment effect in the case of microclimate and litter varibles, but for soil characteristics the impacts will presumably appear in longer term. The increment of total and diffuse light was the greatest in clear-cutting, in gap-cutting the illuminance was intermediate, while light-levels were lower and less variant in preparation cutting and retention tree group. Air and soil temperature as well as vapor pressure deficit increased the most in clear-cutting; both means and variances were the highest in this treamtment. Retention tree group could not buffer the means of the temperature variables, but a small group of tree individuals was able to ameliorate the extremes of the microclimate. Significant increase of soil moisture was measured as a consequence of gap-cutting and less pronouncedly in clear-cutting. Similarly, litter pH and moisture were the highest in these treatment types. Significant increment in soil pH was detected in retention tree group. Through the analysis of microclimate variables during the growing season, we could demonstrate the buffering effect of forest canopy: differences between treatments were the greatest in summer for all microclimate variables. Discussion We can conclude that in oak–hornbeam forest, only less intensive and spatially heterogeneous silvicultural treatments could preserve the stable, cooler and humid below-canopy microclimate, therefore, group selection using gaps and irregular shelterwood systems are favourable. Our findings can support the mitigation of the negative impacts of climate change in managed forest. Moreover, besides basic research we can formulate implications for foresters and conservationists to preserve biodiversity in temperate forests.

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The effects of experimental forestry treatments on site conditions: short response study from an oak-hornbeam forest

10.7287/peerj.preprints.26643 ◽

2018 ◽

Author(s):

Bence Kovács ◽

Flóra Tinya ◽

Erika Guba ◽

Csaba Németh ◽

Vivien Sass ◽

...

Keyword(s):

Forest Canopy ◽

Growing Season ◽

Soil Conditions ◽

Forest Site ◽

Clear Cutting ◽

Silvicultural Treatments ◽

Partial Harvest ◽

Gap Cutting ◽

Tree Group ◽

Microclimate Variables

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Logging impacts on the biogeochemistry of boreal forest soils and nutrient export to aquatic systems: A review

Environmental Reviews ◽

10.1139/a08-006 ◽

2008 ◽

Vol 16 (NA) ◽

pp. 157-179 ◽

Cited By ~ 184

Author(s):

David P. Kreutzweiser ◽

Paul W. Hazlett ◽

John M. Gunn

Keyword(s):

Boreal Forest ◽

Nutrient Availability ◽

Soil Nutrient ◽

Soil Conditions ◽

Soil Nutrient Availability ◽

Clear Cutting ◽

Partial Harvest ◽

Forest Watersheds ◽

Logging Impacts ◽

Receiving Waters

Logging disturbances in boreal forest watersheds can alter biogeochemical processes in soils by changing forest composition, plant uptake rates, soil conditions, moisture and temperature regimes, soil microbial activity, and water fluxes. In general, these changes have often led to short-term increases in soil nutrient availability followed by increased mobility and losses by leaching to receiving waters. Among the studies we reviewed, dissolved organic carbon (DOC) exports usually increased after logging, and nitrogen (N) mineralization and nitrification often increased with resulting increased N availability and exports to receiving waters. Similar processes and responses occurred for phosphorus (P), but to a lesser extent than for N. In most cases, base cations were released and exported to receiving waters after logging. Several studies demonstrated that stem-only or partial-harvest logging reduced the impacts on nutrient release and exports in comparison to whole-tree clear-cutting. Despite these logging-induced increases in soil nutrient availability and movement to receiving waters, most studies reported little or no change in soil chemical properties. However, responses to logging were highly variable and often site specific. The likelihood, extent and magnitude of logging impacts on soil nutrient cycling and exports in boreal forest watersheds will be dependent on soil types, stand and site conditions, hydrological connectivity, post-logging weather patterns, and type and timing of harvest activities. Additionally, logging impacts can interact with, and be confounded by, atmospheric pollutant deposition and climate change. Further watershed-level empirical studies and modeling efforts are required to elucidate these interactions, to improve predictive capabilities, and to advance forest management guidelines for sustaining forest soil productivity and limiting nutrient exports.

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Short-term effects of thinning, clear-cutting and stump harvesting on methane exchange in a boreal forest

Biogeosciences ◽

10.5194/bg-11-6095-2014 ◽

2014 ◽

Vol 11 (21) ◽

pp. 6095-6105 ◽

Cited By ~ 14

Author(s):

E. Sundqvist ◽

P. Vestin ◽

P. Crill ◽

T. Persson ◽

A. Lindroth

Keyword(s):

Boreal Forest ◽

Management Practices ◽

Soil Conditions ◽

Forest Site ◽

Managed Forests ◽

Short Term ◽

Clear Cut ◽

Clear Cutting ◽

Ch4 Production ◽

Short Term Effects

Abstract. Forest management practices can alter soil conditions, affecting the consumption and production processes that control soil methane (CH4) exchange. We studied the short-term effects of thinning, clear-cutting and stump harvesting on the CH4 exchange between soil and atmosphere at a boreal forest site in central Sweden, using an undisturbed plot as the control. Chambers in combination with a high-precision laser gas analyser were used for continuous measurements. Both the undisturbed plot and the thinned plot were net sinks of CH4, whereas the clear-cut plot and the stump harvested plot were net CH4 sources. The CH4 uptake at the thinned plot was reduced in comparison to the undisturbed plot. The shift from sink to source at the clear-cut and stump harvested plots was probably due to a rise in the water table and an increase in soil moisture, leading to lower gas diffusivity and more reduced conditions, which favour CH4 production by archea. Reduced evapotranspiration after harvesting leads to wetter soils, decreased CH4 consumption and increased CH4 production, and should be accounted for in the CH4 budget of managed forests.

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Short-term effects of thinning, clear-cutting and stump harvesting on methane exchange in a boreal forest

Biogeosciences Discussions ◽

10.5194/bgd-11-4637-2014 ◽

2014 ◽

Vol 11 (3) ◽

pp. 4637-4667 ◽

Cited By ~ 2

Author(s):

E. Sundqvist ◽

P. Vestin ◽

P. Crill ◽

T. Persson ◽

A. Lindroth

Keyword(s):

Boreal Forest ◽

Management Practices ◽

Soil Conditions ◽

Forest Site ◽

Managed Forests ◽

Short Term ◽

Clear Cut ◽

Clear Cutting ◽

Ch4 Production ◽

Short Term Effects

Abstract. Forest management practices can alter soil conditions, affecting the consumption and production processes that control soil methane (CH4) exchange. We studied the short-term effects of thinning, clear-cutting and stump harvesting on the CH4 exchange between soil and atmosphere at a boreal forest site in central Sweden, using an undisturbed plot as the control. Chambers in combination with a high precision laser gas analyser were used for continuous measurements. Both the undisturbed plot and the thinned plot were net sinks of CH4, whereas the clear-cut plot and the stump harvested plot were net CH4 sources. The CH4 uptake at the thinned plot was reduced in comparison to the undisturbed plot. The shift from sink to source at the clear-cut and stump harvested plots was probably due to a rise of the water table and an increase in soil moisture, leading to lower gas diffusivity and more reduced conditions which favour CH4 production by archea. Reduced evapotranspiration after harvesting leads to wetter soils, decreased CH4 consumption and increased CH4 production, and should be accounted for in the CH4 budget of managed forests.

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Modelling bi-directional fluxes of methanol and acetaldehyde with the FORCAsT canopy exchange model

10.5194/acp-2016-522 ◽

2016 ◽

Author(s):

Kirsti Ashworth ◽

Serena H. Chung ◽

Karena A. McKinney ◽

Ying Liu ◽

Bill J. Munger ◽

...

Keyword(s):

Stomatal Conductance ◽

Atmospheric Chemistry ◽

Forest Canopy ◽

Global Scale ◽

Exchange Model ◽

Forest Site ◽

Canopy Exchange ◽

Harvard Forest ◽

Leaf Level ◽

Underlying Mechanisms

Abstract. The FORCAsT canopy exchange model was used to investigate the underlying mechanisms governing foliage emissions of methanol and acetaldehyde, two short chain oxygenated volatile organic compounds ubiquitous in the troposphere and known to have strong biogenic sources, at a northern mid-latitude forest site. The explicit representation of the vegetation canopy within the model allowed us to test the hypothesis that stomatal conductance regulates emissions of these compounds to an extent that its influence is observable at the ecosystem-scale, a process not currently considered in regional or global scale atmospheric chemistry models. We found that FORCAsT could only reproduce the magnitude and diurnal profiles of methanol and acetaldehyde fluxes measured at the top of the forest canopy at Harvard Forest if light-dependent emissions were introduced to the model. With the inclusion of such emissions FORCAsT was able to successfully simulate the observed bi-directional exchange of methanol and acetaldehyde. Although we found evidence that stomatal conductance influences methanol fluxes and concentrations at scales beyond the leaf-level, particularly at dawn and dusk, we were able to adequately capture ecosystem exchange without the addition of stomatal control to the standard parameterisations of foliage emissions, suggesting that ecosystem fluxes can be well enough represented by the emissions models currently used.

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Natural Regeneration of the Tree Stand in the Bilberry Spruce Forest—Clear-Cutting Ecotone Complex in the First Post-Logging Decade

Forests ◽

10.3390/f12111542 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1542

Author(s):

Nadezhda V. Genikova ◽

Viktor N. Mamontov ◽

Alexander M. Kryshen ◽

Vladimir A. Kharitonov ◽

Sergey A. Moshnikov ◽

...

Keyword(s):

Natural Regeneration ◽

Forest Canopy ◽

Forest Cover ◽

Forest Type ◽

Ground Cover ◽

Woody Species ◽

Forest Edge ◽

Tree Canopy ◽

Clear Cut ◽

Clear Cutting

Bilberry spruce forests are the most widespread forest type in the European boreal zone. Limiting the clear-cuttings size leads to fragmentation of forest cover and the appearance of large areas of ecotone complexes, composed of forest (F), a transition from forest to the cut-over site under tree canopy (FE), a transition from forest to the cut-over site beyond tree canopy (CE), and the actual clear-cut site (C). Natural regeneration of woody species (spruce, birch, rowan) in the bilberry spruce stand—clear-cut ecotone complex was studied during the first decade after logging. The effects produced by the time since cutting, forest edge aspect, and the ground cover on the emergence and growth of trees and shrubs under forest canopy and openly in the clear-cut were investigated. Estimating the amount and size of different species in the regeneration showed FE and CE width to be 8 m—roughly half the height of first-story trees. Typical forest conditions (F) feature a relatively small amount of regenerating spruce and birch. The most favorable conditions for natural regeneration of spruce in the clear-cut—mature bilberry spruce stand ecotone are at the forest edge in areas of transition both towards the forest and towards the clear-cut (FE and CE). Clear-cut areas farther from the forest edge (C) offer an advantage to regenerating birch, which grows densely and actively in this area.

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Electromagnetic Induction Is a Fast and Non-Destructive Approach to Estimate the Influence of Subsurface Heterogeneity on Forest Canopy Structure

Water ◽

10.3390/w13223218 ◽

2021 ◽

Vol 13 (22) ◽

pp. 3218

Author(s):

Simon Damien Carrière ◽

Nicolas K. Martin-StPaul ◽

Claude Doussan ◽

François Courbet ◽

Hendrik Davi ◽

...

Keyword(s):

Forest Structure ◽

Electromagnetic Induction ◽

Forest Canopy ◽

Soil Depth ◽

Soil Conditions ◽

Mediterranean Forests ◽

Area Index ◽

Edaphic Conditions ◽

Plant Area Index ◽

Plant Area

The spatial forest structure that drives the functioning of these ecosystems and their response to global change is closely linked to edaphic conditions. However, the latter properties are particularly difficult to characterize in forest areas developed on karst, where soil is highly rocky and heterogeneous. In this work, we investigated whether geophysics, and more specifically electromagnetic induction (EMI), can provide a better understanding of forest structure. We use EMI (EM31, Geonics Limited, Ontario, Canada) to study the spatial variability of ground properties in two different Mediterranean forests. A naturally post-fire regenerated forest composed of Aleppo pines and Holm oaks and a monospecific plantation of Altlas cedar. To better interpret EMI results, we used electrical resistivity tomography (ERT), soil depth surveys, and field observations. Vegetation was also characterized using hemispherical photographs that allowed to calculate plant area index (PAI). Our results show that the variability of ground properties contribute to explaining the variability in the vegetation cover development (plant area index). Vegetation density is higher in areas where the soil is deeper. We showed a significant correlation between edaphic conditions and tree development in the naturally regenerated forest, but this relationship is clearly weaker in the cedar plantation. We hypothesized that regular planting after subsoiling, as well as sylvicultural practices (thinning and pruning) influenced the expected relationship between vegetation structure and soil conditions measured by EMI. This work opens up new research avenues to better understand the interplay between soil and subsoil variability and forest response to climate change.

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ForBioFunCtioN: Forest soil carbon and the effects of climate change and forest management

10.5194/egusphere-egu21-5553 ◽

2021 ◽

Author(s):

Carl-Fredrik Johannesson ◽

Klaus Steenberg Larsen ◽

Brunon Malicki ◽

Jenni Nordén

Keyword(s):

Climate Change ◽

Forest Management ◽

Forest Soil ◽

Large Scale ◽

C Sequestration ◽

Soil Conditions ◽

High Temporal Resolution ◽

Soil C ◽

Positive Effects ◽

Clear Cutting

Boreal forests are among the most carbon (C) rich forest types in the world and store up to 80% of its total C in the soil. Forest soil C development under climate change has received increased scientific attention yet large uncertainties remain, not least in terms of magnitude and direction of soil C responses. As with climate change, large uncertainties remain in terms of the effects of forest management on soil C sequestration and storage. Nonetheless, it is clear that forest management measures can have far reaching effects on ecosystem functioning and soil conditions. For example, clear cutting is a widely undertaken felling method in Scandinavia which profoundly affects the forest ecosystem and its functioning, including the soil. Nitrogen (N) fertilization is another common practice in Scandinavia which, despite uncertainties regarding effects on soil C dynamics, is being promoted as a climate change mitigation tool. A more novel practice of biochar addition to soils has been shown to have positive effects on soil conditions, including soil C storage, but studies on biochar in the context of forests are few.In the face of climate change, the ForBioFunCtioN project is dedicated to investigating the response of boreal forest soil CO2 and CH4 fluxes to experimentally increased temperatures and increased precipitation &#8211; climatic changes in line with projections over Norway &#8211; within a forest management context. The experiment is set in a Norwegian spruce-dominated bilberry chronosequence, including a clear-cut site, a middle-aged thinned stand, a mature stand and an old unmanaged stand. Warming, simulated increased precipitation, N fertilizer and biochar additions will be applied on experimental plots in an additive manner that allows for disentangling the effects of individual parameters from interaction effects. Flux measurements will be undertaken at high temporal resolution using the state-of-the-art LI-7810 Trace Gas Analyzer (&#169;LI-COR Biosciences). The presentation will show the experimental setup and first measurements from the large-scale experiment.

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Temporal changes in boreal forest tree canopy cover along a gradient of gamma radiation

Canadian Journal of Botany ◽

10.1139/b85-003 ◽

1985 ◽

Vol 63 (1) ◽

pp. 15-20 ◽

Cited By ~ 8

Author(s):

B. D. Amiro ◽

J. R. Dugle

Keyword(s):

Gamma Radiation ◽

Boreal Forest ◽

Gamma Rays ◽

Forest Canopy ◽

Canopy Cover ◽

Woody Species ◽

Tree Canopy ◽

Forest Site ◽

Dose Rates ◽

Tree Canopy Cover

A forest site in southeastern Manitoba has been irradiated by a point source of gamma rays continuously since 1973, and measurements have been made yearly to study the change in boreal forest canopy cover along the radiation gradient. After 10 years of chronic irradiation, a zone of total tree death has resulted from mean dose rates between 25 and 62 mGy h−1. Tree canopy cover was reduced at mean dose rates exceeding ~ 4.5 mGy h−1 and the largest reduction occurred in the first 2 years of irradiation. The temporal responses of seven woody species to gamma radiation are presented. Bebb's willow, trembling aspen, speckled alder, and paper birch were less sensitive to radiation than black spruce, balsam fir, and jack pine. The results confirm that gymnosperms are more sensitive to gamma rays than angiosperms.

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Are resources allocated differently to symbiosis and reproduction in Geranium sylvaticum under different light conditions?

Canadian Journal of Botany ◽

10.1139/b03-142 ◽

2004 ◽

Vol 82 (1) ◽

pp. 89-95 ◽

Cited By ~ 16

Author(s):

Jarkko Korhonen ◽

Minna-Maarit Kytöviita ◽

Pirkko Siikamäki

Keyword(s):

Resource Allocation ◽

Forest Canopy ◽

Light Availability ◽

Growing Season ◽

High Light ◽

Mycorrhizal Colonization ◽

Fungal Colonization ◽

Low Light ◽

Light Levels ◽

Dark Septate Fungi

Light levels under the forest canopy are low and generally limit plant photosynthetic gains. We hypothesized that in low-light habitats, plant photosynthate acquisition is too low to allow the same magnitude of resource allocation to symbiosis and reproduction as in high-light habitats. We tested this hypothesis in a field study where Geranium sylvaticum L. plants were collected on three occasions during the growing season from shade and light habitats. In addition, we investigated the relationship between mycorrhizal colonization level and soil nutrient levels in shade and high-light habitats over a growing season. We found that light availability affects resource allocation in G. sylvaticum. Plants were intensively colonized with both arbuscular mycorrhizal and dark septate fungi, and the colonization intensities of these two different groups of fungi correlated positively with each other. In comparison with high-light meadows, mycorrhizal colonization levels were as high or higher in low-light forest habitats, but plants produced fewer flowers. This indicates that allocation to symbiosis was of higher priority than allocation to reproduction in low light. Seed size was not affected by light levels and did not correlate with fungal colonization levels. We found no relationship between fungal colonization levels and soil characteristics.Key words: arbuscular mycorrhiza, dark septate fungi, Geranium sylvaticum, reproduction, shade.

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