An alternative to clear-cutting in the boreal forest of Alaska: a 27-year study of regeneration after shelterwood harvesting

2001 ◽  
Vol 31 (6) ◽  
pp. 999-1011 ◽  
Author(s):  
T L Wurtz ◽  
J C Zasada
Keyword(s):  
Forest Management ◽  
Boreal Forest ◽  
Picea Glauca ◽  
Management Practices ◽  
White Spruce ◽  
Seed Crop ◽  
Clear Cut ◽  
Calamagrostis Canadensis ◽  
Clear Cutting ◽  
All Treatment

We present 27-year results from a comparison of clear-cutting and shelterwood harvesting in the boreal forest of Alaska. Three patch clear-cut and three shelterwood units were harvested in 1972; about 100 dispersed white spruce (Picea glauca (Moench) Voss) leave trees per hectare were retained in the shelterwoods. Units were mechanically scarified and an exceptionally large seed-crop was dispersed that year. Shelterwood trees were removed after 15 years. After 27 years, overstory treatment had no effect on the density or growth of the species we studied, while scarification had highly significant effects. In 1999, scarified areas were densely populated with white spruce seedlings and saplings (118 000 – 129 000 stems/ha, with spruce in 100% of plots). Unscarified areas had far fewer spruce stems but were nevertheless well stocked (11 000 – 15 000 stems/ha, with 87% frequency). Initially, spruce grew best on scarified surfaces, but by 27 years, growth of the tallest spruce saplings was significantly greater on unscarified than scarified surfaces. By 27 years, cover of the grass Calamagrostis canadensis (Michx.) Nutt. had returned to preharvest levels in all treatment types. Because criteria for evaluating forest management practices have changed since this study was begun, partial overstory retention systems for the management of Alaska's boreal forest deserve further study.

scholarly journals Impacts of Clear-Cutting of a Boreal Forest on Carbon Dioxide, Methane and Nitrous Oxide Fluxes

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 961
Author(s):  
Patrik Vestin ◽  
Meelis Mölder ◽  
Natascha Kljun ◽  
Zhanzhang Cai ◽  
Abdulghani Hasan ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Nitrous Oxide ◽  
Forest Management ◽  
Boreal Forest ◽  
Total Carbon ◽  
Clear Cut ◽  
Clear Cutting ◽  
N2o Fluxes ◽  
Ch4 And N2o ◽  
Ghg Fluxes

The 2015 Paris Agreement encourages stakeholders to implement sustainable forest management policies to mitigate anthropogenic emissions of greenhouse gases (GHG). The net effects of forest management on the climate and the environment are, however, still not completely understood, partially as a result of a lack of long-term measurements of GHG fluxes in managed forests. During the period 2010–2013, we simultaneously measured carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes using the flux-gradient technique at two clear-cut plots of different degrees of wetness, located in central Sweden. The measurements started approx. one year after clear-cutting, directly following soil scarification and planting. The study focused on robust inter-plot comparisons, spatial and temporal dynamics of GHG fluxes, and the determination of the global warming potential of a clear-cut boreal forest. The clear-cutting resulted in significant emissions of GHGs at both the wet and the dry plot. The degree of wetness determined, directly or indirectly, the relative contribution of each GHG to the total budgets. Faster establishment of vegetation on the wet plot reduced total emissions of CO2 as compared to the dry plot but this was partially offset by higher CH4 emissions. Waterlogging following clear-cutting likely caused both plots to switch from sinks to sources of CH4. In addition, there were periods with N2O uptake at the wet plot, although both plots were net sources of N2O on an annual basis. We observed clear diel patters in CO2, CH4 and N2O fluxes during the growing season at both plots, with the exception of CH4 at the dry plot. The total three-year carbon budgets were 4107 gCO2-equivalent m−2 and 5274 gCO2-equivalent m−2 at the wet and the dry plots, respectively. CO2 contributed 91.8% to the total carbon budget at the wet plot and 98.2% at the dry plot. For the only full year with N2O measurements, the total GHG budgets were 1069.9 gCO2-eqvivalents m−2 and 1695.7 gCO2-eqvivalents m−2 at the wet and dry plot, respectively. At the wet plot, CH4 contributed 3.7%, while N2O contributed 7.3%. At the dry plot, CH4 and N2O contributed 1.5% and 7.6%, respectively. Our results emphasize the importance of considering the effects of the three GHGs on the climate for any forest management policy aiming at enhancing the mitigation potential of forests.

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

2014 ◽  
Vol 11 (21) ◽  
pp. 6095-6105 ◽  
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.

Nitrogen uptake characteristics for roots of conifer seedlings and common boreal forest competitor species

2003 ◽  
Vol 33 (1) ◽  
pp. 156-163 ◽  
Author(s):  
Ryan D Hangs ◽  
J Diane Knight ◽  
Ken CJ Van Rees
Keyword(s):  
Boreal Forest ◽  
Populus Tremuloides ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
N Uptake ◽  
White Spruce ◽  
Jack Pine ◽  
Calamagrostis Canadensis ◽  
Successional Species ◽  
Menten Kinetic

Little is known about the N uptake abilities of competitor species and planted seedlings in the boreal forest. The objective of this study was to determine the Michaelis–Menten kinetic parameters of NH4+ and NO3– for white spruce (Picea glauca (Moench) Voss) and jack pine (Pinus banksiana Lamb.) seedlings, and three competitive common boreal forest early successional species: aspen (Populus tremuloides Michx.), fireweed (Epilobium angustifolium L.), and cala magrostis (Calamagrostis canadensis (Michx.) Beauv.). Uptake kinetics were measured in hydroponic cultures and expressed as maximum uptake (Imax) and ion affinity (Km). The ranking of Imax values (pmol·cm-2·s–1) for NH4+ uptake was calamagrostis (84.6), fireweed (58.1), white spruce (20.7), aspen (12.5), and jack pine (10.9), and for NO3– uptake was calamagrostis (17.7), fireweed (12.5), aspen (5.8), white spruce (4.5), and jack pine (2.1). The ranking of Km values (µM) for NH4+ uptake was calamagrostis (125.9), fireweed (163.8), aspen (205.7), white spruce (217.1), and jack pine (270.5), and for NO3– uptake was calamagrostis (229.9), fireweed (274.6), aspen (336.5), white spruce (344.5), and jack pine (350.5). Calamagrostis exhibited the greatest uptake rates and affinity for NH4+ and NO3–, suggesting that silviculture practices that specifically reduce establishment of this grass should benefit the growth of planted seedlings.

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

2014 ◽  
Vol 11 (3) ◽  
pp. 4637-4667 ◽  
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.

Radial Growth Decline of White Spruce (Picea glauca) During Hot Summers without Drought: Preliminary Results from a Study Site South of a Boreal Forest Border

2022 ◽  
Author(s):  
Andrei Lapenis ◽  
George Robinson ◽  
Gregory B. Lawrence
Keyword(s):  
New York ◽  
Boreal Forest ◽  
Picea Glauca ◽  
Radial Growth ◽  
Summer Precipitation ◽  
White Spruce ◽  
Southern Limit ◽  
Central New York ◽  
Growth Decline ◽  
Hot Days

Here we investigate the possible<sup></sup> future response of white spruce (Picea glauca) to a warmer climate by studying trees planted 90 years ago near the southern limit of their climate tolerance in central New York, 300 km south of the boreal forest where this species is prevalent. We employed high-frequency recording dendrometers to determine radial growth phenology of six mature white spruce trees during 2013-2017. Results demonstrate significant reductions in the length of radial growth periods inversely proportional to the number of hot days with air temperature exceeding 30 oC. During years with very hot summers, the start of radial growth began about 3 days earlier than the 2013-2017 average. However, in those same years the end of radial growth was also about 17 days earlier resulting in a shorter (70 versus 100 day), radial growth season. Abundant (350-500 mm) summer precipitation, which resulted in soil moisture values of 20-30% allowed us to dismiss drought as a factor. Instead, a likely cause of reduced radial growth was mean temperature that exceeded daily average of 30<sup> o</sup>C that lead to photoinhibition.

Dynamics of regeneration gaps following harvest of aspen stands

2006 ◽  
Vol 36 (7) ◽  
pp. 1818-1833 ◽  
Author(s):  
Daniel A MacIsaac ◽  
Philip G Comeau ◽  
S Ellen Macdonald
Keyword(s):  
Spatial Heterogeneity ◽  
Populus Tremuloides ◽  
Picea Glauca ◽  
Natural Disturbance ◽  
White Spruce ◽  
Deciduous Trees ◽  
Trembling Aspen ◽  
Calamagrostis Canadensis ◽  
Edaphic Conditions ◽  
Over Time

This study assessed the dynamics of gap development in postharvest regeneration in five stands in northwestern Alberta dominated by trembling aspen (Populus tremuloides Michx.). The pattern of gap development over time was determined from analysis of air photographs taken preharvest and 1, 4, 10, and 12 years postharvest. The area of each stand covered by gaps increased after harvest because of the addition of harvest-related gaps over and above those that had been present prior to harvest. The blocks we studied had a combined gap area of up to 29% of stand area 12 years postharvest. We measured regeneration characteristics, microsite, soil, light, and browse conditions in 30 aspen regeneration gaps (gaps in regeneration that were not gaps preharvest and were not due to obvious harvest-related disturbance) 14 years following harvest. Although deciduous trees within postharvest regeneration gaps were the same age as those outside (i.e., in a fully stocked matrix of newly established even-aged aspen stems), they were often suppressed, with significantly lower density and growth. Within the 14-year-old postharvest regenerating aspen stands, aspen height varied from 1 to 11 m; this substantial variability appeared to be largely due to the influence of browsing. There was little evidence of ongoing regeneration within postharvest regeneration gaps, indicating that these gaps will probably persist over time. This may impact future deciduous stocking and volume. It is unknown what may have initiated the formation of these gaps, although results suggest that they are not due to edaphic conditions or disease in the preharvest stands. There is evidence that bluejoint (Calamagrostis canadensis (Michx.) Beauv.) cover and browsing are important factors in the maintenance of postharvest regeneration gaps. The spatial heterogeneity resulting from gaps could be advantageous, however, either as part of ecosystem-based management emulating natural disturbance or as a template for mixedwood management, where white spruce (Picea glauca (Moench) Voss) are established in gaps.

Assessing the implications of a carbon market for boreal forest management

2011 ◽  
Vol 87 (03) ◽  
pp. 367-381
Author(s):  
Stewart Elgie ◽  
Geoffrey R. Mccarney ◽  
Wiktor L. Adamowicz
Keyword(s):  
Forest Management ◽  
Boreal Forest ◽  
Management Practices ◽  
Sustainable Forest Management ◽  
Carbon Price ◽  
Integrated Modelling ◽  
Harvest Scheduling ◽  
Boreal Plains ◽  
Management Changes ◽  
Modelling Approach

Canada's forests —particularly the boreal—are a major storehouse of carbon. How they are managed could significantly affect Canada's greenhouse gas emissions while also presenting a new revenue source for forest managers. This study attempts to assess how a carbon price could affect forest management, particularly in Canada's boreal plains region. An integrated modelling approach is developed to incorporate both forest carbon and timber supply considerations within an optimal management framework. This modelling approach allows for consideration of alternative market and regula tory scenarios, along with a range of possible management intensity and harvest scheduling options over the landscape. The overall conclusion is that carbon incentives will increase the value of the boreal forest—potentially quite signifi cantly— and will generally encourage management changes consistent with sustainable forest management practices.

Clear-cutting and regeneration practices in Quebec boreal balsam fir forest: effects on snowshoe hare

2001 ◽  
Vol 31 (1) ◽  
pp. 41-51 ◽  
Author(s):  
Sonia de Bellefeuille ◽  
Louis Bélanger ◽  
Jean Huot ◽  
Agathe Cimon
Keyword(s):  
Boreal Forest ◽  
Natural Regeneration ◽  
Lepus Americanus ◽  
Seedling Stage ◽  
Snowshoe Hare ◽  
Short Term ◽  
Clear Cut ◽  
Clear Cutting ◽  
Term Basis ◽  
Protective Cover

We compared utilization by the snowshoe hare (Lepus americanus Erxleben) of recent clearcuts subjected to three regeneration scenarios commonly used in boreal forest: natural regeneration, plantation with herbicide release (glyphosate), and plantation with manual release (brushsaw). Refuges for snowshoe hare, on a landscape dominated by clearcuts, were also investigated. Colonization of regenerating sites by the hare comes late in the humid boreal forest because clear-cut stands take more than 10 years to reach the sapling stage. Our sites were in the seedling stage 7–9 years after cutting, and hares avoided them year round because of an inadequate protective cover. Therefore, regeneration treatments did not affect habitat use by the hare on a short-term basis. During the seedling stage, the snowshoe hare were found in the remaining forest which occupied at least 25% of the area of each home range. The preservation of residual forests is thus essential to maintain local populations on an area dominated by commercial clearcuts.

scholarly journals Group selection harvesting supports diversity of forest specialist carabids

2019 ◽  
Vol 2 ◽  
Author(s):  
Bela Tóthmérész ◽  
Tibor Magura ◽  
Szabolcs Mizser ◽  
David D. Nagy
Keyword(s):  
Forest Management ◽  
Group Selection ◽  
Environmental Changes ◽  
Control Area ◽  
Oak Forests ◽  
Pitfall Traps ◽  
Clear Cut ◽  
Clear Cutting ◽  
Specialist Species ◽  
Selection Harvesting

Increased fragmentation and considerable environmental changes in native forests caused by the timber-oriented forest managements are threatening the biodiversity of forests. As a remediation, uneven-aged approach is recommended during forest management, because this is less intensive and could be less harmful than even-aged practices. We tested the effects of clear-cutting (as even-aged method) and group selection harvesting (as uneven-aged method) on carabids in lowland oak forests. Pitfall traps and litter sifting were used during the study. We found that the total number of species was significantly higher in the gaps harvested by group selection and in the clear-cut than in the mature forests (control area). The species richness of forest specialist species was significantly lower in the clear-cuts than in the other area. Our findings demonstrated that the conventional clear-cutting caused a decrease in the number of forest specialist species. Therefore, group selection method should be favoured during forest management to maintain diversity.

Sign in / Sign up

Export Citation Format

Share Document