Статті в журналах: "Uneven-aged forest"

1

Yang, Feng’e, and Shashi Kant. "Forest-level analyses of uneven-aged hardwood forests." Canadian Journal of Forest Research 38, no. 2 (February 2008): 376–93. http://dx.doi.org/10.1139/x07-109.

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The matrix growth models of maple–beech and maple stands in the uneven-aged mixed species hardwood forests in the Algonquin region of Ontario are specified as a system of simultaneous growth equations with restrictions on the sum of transition probabilities. The specified system of growth equations is estimated using the seemingly unrelated regression technique. The estimated matrix growth models are used to predict the growth dynamics of stands. Linear and nonlinear programming models are used to seek optimal management regimes and to analyze the trade-offs between financial returns and structural diversity at the forest level as well as at the stand level. The optimal harvesting schedules obtained at the forest level without ecological (residual basal area or structural diversity) constraints are identical with those obtained at the stand level; however, for higher structural diversity at the forest level, the optimal harvesting schedules based on forest-level decision making are found to be different from those based on stand-level decision making.

2

Susaeta, Andres, Kotryna Klizentyte, Ajay Sharma, and Damian C. Adams. "Can uneven-aged management improve the economic performance of longleaf pine?" Canadian Journal of Forest Research 51, no. 9 (September 2021): 1307–15. http://dx.doi.org/10.1139/cjfr-2020-0437.

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Longleaf pine (Pinus palustris Mill.) is a keystone tree species in the Coastal Plain of the southern United States. To reverse habitat loss and restore critically important forest ecosystem services in this region dominated by private landownership, longleaf pine’s economic performance must be addressed. Uneven-aged forest management has been suggested as a viable alternative for longleaf pine, but evidence of its economic performance under uneven-aged versus even-aged management is lacking. Here, we compare the economic viability of three competing longleaf pine management scenarios — thinned even-aged, unthinned even-aged (conservation and non-conservation land objectives), and uneven-aged — considering timber and nontimber benefits. We find that managing existing uneven-aged longleaf pine forests with a 10-year cutting cycle is economically preferred to even-aged management for land conservation ($1643.9·ha−1 versus $1548.8 to $1641.6·ha−1). However, these estimates exclude costs associated with switching to uneven-aged management ($174.3 to $694.9·ha−1), which are considerable. Annual subsidies of between $5 and $22·ha−1 for 50 years would be required to offset costs of conversion to uneven-aged management. For establishment of new longleaf pine stands, an uneven-aged scenario would be the economically preferred management approach, providing higher economic gains ($176.9·ha−1) than unthinned, high-density even-aged management when the primary objective is timber production.

3

Rämö, Janne, and Olli Tahvonen. "Economics of harvesting uneven-aged forest stands in Fennoscandia." Scandinavian Journal of Forest Research 29, no. 8 (November 17, 2014): 777–92. http://dx.doi.org/10.1080/02827581.2014.982166.

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4

Treiman, Thomas, John Dwyer, and David Larsen. "Long-Term Economic Simulation: Even-Aged and Uneven-Aged Examples from the Missouri Ozark Forest Ecosystem Project (MOFEP)." Northern Journal of Applied Forestry 22, no. 1 (March 1, 2005): 42–47. http://dx.doi.org/10.1093/njaf/22.1.42.

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Abstract Much of the software and many of the algorithms commonly used to simulate forest growth and harvesting activities have been optimized for short-term projections based primarily on larger-sized trees and are focused on even-aged silvicultural systems. Using data on trees 1.5 in. dbh and larger from the Missouri Ozark Forest Ecosystem Project (MOFEP), we have adapted the widely available Landscape Management System (LMS) and Forest Vegetation Simulator (FVS) software to make long-term simulations using even and uneven-aged silvicultural management systems. MOFEP is designed to test the long-term effects of even-aged, uneven-aged, and no harvest treatments on a variety of ecosystem attributes. To simulate the economic outcomes of these three treatments, we have written new LMS algorithms that simulate the effects of uneven-aged harvesting. Our results show that in the Missouri Ozarks even-aged and uneven-aged management silvicultural systems yield long-term (100 years) economic outcomes that are not statistically different. This result reinforces the need for land managers or landowners to consider esthetics, nontraditional forest products, and other nonmarket values in their decision matrix. North. J. Appl. For. 22(1):42– 47.

5

Kuuluvainen, Timo, Olli Tahvonen, and Tuomas Aakala. "Even-Aged and Uneven-Aged Forest Management in Boreal Fennoscandia: A Review." AMBIO 41, no. 7 (May 12, 2012): 720–37. http://dx.doi.org/10.1007/s13280-012-0289-y.

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6

Hood, S. M., S. M. Zedaker,, W. M. Aust, and D. W. Smith. "Universal Soil Loss Equation (USLE)-Predicted Soil Loss for Harvesting Regimes in Appalachian Hardwoods." Northern Journal of Applied Forestry 19, no. 2 (June 1, 2002): 53–58. http://dx.doi.org/10.1093/njaf/19.2.53.

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Abstract Soil erosion from forest harvesting is a major environmental concern. While there has been research comparing soil erosion on clearcut regeneration harvests with that on uncut forests, there has been little focus on the differences among common silvicultural harvests. Forest certification standards that are currently being evaluated for adoption across the country often encourage uneven-aged systems over even-aged or two-aged systems. We estimated soil loss using the Universal Soil Loss Equation (USLE) for forest land on five harvested treatments in the southern Appalachians. Treatments included a clearcut, leave-tree harvest, shelterwood, group selection, and uncut control. Results predicted that the group selection would have approximately 10 tons/ac more soil loss over a 100 yr rotation than the other harvested treatments. The higher rate was primarily from skid trails when the treatment was reentered for harvesting. These results should be considered when weighing the benefits of uneven-aged silviculture over even-aged or two-aged silviculture.

7

Shanin, Vladimir, Sauli Valkonen, Pavel Grabarnik, and Raisa Mäkipää. "Using forest ecosystem simulation model EFIMOD in planning uneven-aged forest management." Forest Ecology and Management 378 (October 2016): 193–205. http://dx.doi.org/10.1016/j.foreco.2016.07.041.

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8

Bachofen, Hansheinrich. "Nachhaltige Verjüngung in ungleichförmigen Beständen | Sustainable recruitment in uneven aged stands." Schweizerische Zeitschrift fur Forstwesen 160, no. 1 (January 1, 2009): 2–10. http://dx.doi.org/10.3188/szf.2009.0002.

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Sustainable recruitment is necessary in uneven aged and inhomogeneous forest stands (selection forests, group plenter forests, continuous cover forests) to guarantee long-lasting structure. In protection forests, an abundant tree regeneration is of utmost importance. If the regeneration rate is small, the protection function will eventually be at risk. Today, adequate methods are missing that precisely estimate self-sustaining regeneration rates. Therefore, in this study the actual state of regenerating trees was assessed in monitoring plots at various altitudes. The results can be considered as generalised ranges of sustained regeneration rates. It was found that regeneration rates in selection forests at higher altitudes were lower than in more productive forests at lower altitudes. According to theoretical considerations, mortality in youth forests is dependent on height growth. It follows that mortality of regenerating trees in less productive, balanced selection forests is smaller than in more productive ones.

9

Dwyer, John P., Daniel C. Dey, William D. Walter, and Randy G. Jensen. "Harvest Impacts in Uneven-Aged and Even-Aged Missouri Ozark Forests." Northern Journal of Applied Forestry 21, no. 4 (December 1, 2004): 187–93. http://dx.doi.org/10.1093/njaf/21.4.187.

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Abstract Forest managers are concerned about the potential damage to residual trees and site from cyclic harvest re-entries into the same forest stand. This study summarizes logging and felling damage resulting from the harvesting of silvicultural treatments on a large landscape experiment in southern Missouri that is designed to compare impacts of even-aged, uneven-aged and no management on a wide array of ecosystem components. Although damage levels to bole and crown of leave trees was low for all treatments, the individual tree selection (uneven-aged) treatment did show: (1) higher levels of surface area skidder impact; (2) higher percentage of leave trees with one or more bole wounds; (3) higher number of bole wounds; (4) higher percentage of wounded trees in the dominant and co-dominant crown classes; and (5) the highest percentage of leave trees impacted by logging activity. Preharvest planning that involves the layout and discussion with the skidder operator(s) will reduce the area impacted by skidding to less than 12%. Also, the probability of a bole wound to a residual tree can be reduced to less than 5% if skid trails are kept 30 ft or more from the leave tree. North. J. Appl. For. 21(4):187–193.

10

Willim, Katharina, Melissa Stiers, Peter Annighöfer, Martin Ehbrecht, Christian Ammer, and Dominik Seidel. "Spatial Patterns of Structural Complexity in Differently Managed and Unmanaged Beech-Dominated Forests in Central Europe." Remote Sensing 12, no. 12 (June 12, 2020): 1907. http://dx.doi.org/10.3390/rs12121907.

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One of the main goals of modern silviculture is to emulate the structural complexity of old-growth forests. In this context, it is of advantage to identify a target state of structural complexity at the stand level and to analyze the spatial characteristics that led to the desired complexity of forest structures in primary forest references. In this study, we used 3D forest scenes captured by terrestrial laser scanning (TLS) to identify spatial patterns of structural complexity of differently managed and unmanaged European forests dominated by beech (Fagus sylvatica L.). We scanned in managed even-aged and uneven-aged stands, as well as in formerly managed forests (National Parks) and primary forests. For three different forest strata, representing the understory, the midstory, and the overstory of a forest stand, we determined the structural complexity mathematically using fractal analysis. Beyond that, we analyzed the density, as well as the horizontal and vertical distribution of plant material. For all three forest strata, we observed differences in structural complexity between the different forest types. Within the lower and middle strata, the investigated primary forests showed a random to regular distribution of plant material, as well as a complex understory structure as a result of pronounced natural decay. Compared to the primary forests, the managed uneven-aged stands showed quite similar spatial patterns of distribution of plant material, but on average a higher space occupation in the lower and middle forest stratum. Our results suggest that single tree or group selection cutting is a useful management tool to imitate old-growth structures of undisturbed beech-dominated forests.

11

Wagner, John E., Diane Kiernan, and Eddie Bevilacqua. "Economically derived yields for even- and uneven-aged stands." Canadian Journal of Forest Research 43, no. 8 (August 2013): 691–98. http://dx.doi.org/10.1139/cjfr-2012-0503.

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We propose an approach to develop economic-based yields for even- and uneven-aged stands that could be compared with yields generated by using silvicultural treatments. Economic-based yields are derived from economic parameters that describe markets and the landowner’s ownership goals and objectives. This study highlights five conclusions. First, economic-based yields define a lower bound on silvicultural-based yields required to just satisfy these economic parameters and provide a metric of confidence that a silvicultural prescription would increase (or decrease) the landowner’s wealth. Second, a main driver of the economic-based yields is the opportunity costs of the reserve growing stock or regeneration costs and the land. Third, the economic-based yields followed a similar pattern regardless of whether the stand was defined as even- or uneven-aged. Fourth, the economic-based yields illustrate the physical impacts that recreational leases, taxes, or the sale of nontimber forest ecosystem goods and services have on this lower bound. Finally, if the economic-based yields are greater than the silvicultural-based yields and if physical output estimates could be derived for the suite of nontimber forest ecosystem goods and services resulting from the forest structure, then implied economic values for this suite of goods and services could be derived using the models presented.

12

Jayathunga, Sadeepa, Toshiaki Owari, and Satoshi Tsuyuki. "Digital Aerial Photogrammetry for Uneven-Aged Forest Management: Assessing the Potential to Reconstruct Canopy Structure and Estimate Living Biomass." Remote Sensing 11, no. 3 (February 8, 2019): 338. http://dx.doi.org/10.3390/rs11030338.

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Scientifically robust yet economical and efficient methods are required to gather information about larger areas of uneven-aged forest resources, particularly at the landscape level, to reduce deforestation and forest degradation and to support the sustainable management of forest resources. In this study, we examined the potential of digital aerial photogrammetry (DAP) for assessing uneven-aged forest resources. Specifically, we tested the performance of biomass estimation by varying the conditions of several factors, e.g., image downscaling, vegetation metric extraction (point cloud- and canopy height model (CHM)-derived), modeling method ((simple linear regression (SLR), multiple linear regression (MLR), and random forest (RF)), and season (leaf-on and leaf-off). We built dense point clouds and CHMs using high-resolution aerial imagery collected in leaf-on and leaf-off conditions of an uneven-aged mixed conifer–broadleaf forest. DAP-derived vegetation metrics were then used to predict the dominant height and living biomass (total, conifer, and broadleaf) at the plot level. Our results demonstrated that image downscaling had a negative impact on the accuracy of the dominant height and biomass estimation in leaf-on conditions. In comparison to CHM-derived vegetation metrics, point cloud-derived metrics performed better in dominant height and biomass (total and conifer) estimations. Although the SLR (%RMSE = 21.1) and MLR (%RMSE = 18.1) modeling methods produced acceptable results for total biomass estimations, RF modeling significantly improved the plot-level total biomass estimation accuracy (%RMSE of 12.0 for leaf-on data). Overall, leaf-on DAP performed better in total biomass estimation compared to leaf-off DAP (%RMSE of 15.0 using RF modeling). Nevertheless, conifer biomass estimation accuracy improved when leaf-off data were used (from a %RMSE of 32.1 leaf-on to 23.8 leaf-off using RF modeling). Leaf-off DAP had a negative impact on the broadleaf biomass estimation (%RMSE > 35% for SLR, MLR, and RF modeling). Our results demonstrated that the performance of forest biomass estimation for uneven-aged forests varied with statistical representations as well as data sources. Thus, it would be appropriate to explore different statistical approaches (e.g., parametric and nonparametric) and data sources (e.g., different image resolutions, vegetation metrics, and leaf-on and leaf-off data) to inform the interpretation of remotely sensed data for biomass estimation for uneven-aged forest resources.

13

Knoke, Thomas. "Zur finanziellen Attraktivität von Dauerwaldwirtschaft und Überführung: eine Literaturanalyse | On the financial attractiveness of continuous cover forest management and transformation: a review." Schweizerische Zeitschrift fur Forstwesen 160, no. 6 (June 1, 2009): 152–61. http://dx.doi.org/10.3188/szf.2009.0152.

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Even after decades of discussion on the economic advantages or disadvantages of a forestry management practice using uneven-aged stands there is still no consistent description of the conditions which make continuous cover forests more economically interesting than forests with an age-class gradation. Based on existing references this paper tries to point out such preconditions. Studies of comparative statics at management unit level are presented; these often reveal a clear advantage of continuous cover forests in Central European circumstances. The greater resistance of a forest with continuous cover to abiotic and biotic damage, together with the possibility of harvesting trees when their individual financial maturity is attained, are important reasons for this result. Studies at stand level on the transformation of even-aged into uneven-aged forests do not always show an advantage for continuous cover forest. Here, it seems to be important whether or not interest rates form the basis for the conclusions, and if so how high these interest rates are, also at what age transformation begins. Earlier and more regular net revenues during the process of stand transformation into continuous cover systems can lead to superior financial results when compared to even-aged silvicultural systems . However, present knowledge is still relatively scarce in what concerns possible differences in logging and overhead costs as well as costs for forest roads in the two silvicultural systems under comparison.

14

Zeller, Laura, Astor Toraño Caicoya, and Hans Pretzsch. "Analyzing the effect of silvicultural management on the trade-off between stand structural heterogeneity and productivity over time." European Journal of Forest Research 140, no. 3 (February 1, 2021): 615–34. http://dx.doi.org/10.1007/s10342-020-01350-z.

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AbstractThis study combined an empirically based simulation with an analysis of the trade-off between structural heterogeneity and stand productivity depending on time, spatial scale, and silvicultural management, whereas volume growth and tree species diversity have been examined in detail, the role of forest structure and its interdependencies with stand productivity has only lately become a stronger research focus. We used the growth simulator SILVA to examine the development of stand structural heterogeneity and its trade-off with stand productivity in age-class versus uneven-aged pure and mixed spruce and beech stands at different spatial scales over 100 years. Those stands were based on typical forest types in Bavaria and were representative of forests in Central Europe. We examined how stand structure and its trade-off with productivity were modified by a multifunctional, a production-oriented, and a set-aside management scenario. The production-oriented management scenario applied to uneven-aged stands led to a reduction in structural heterogeneity per unit of productivity over time. In age-class stands, the production-oriented scenario was able to maintain the initial structural heterogeneity. The structural heterogeneity per unit of productivity increased more strongly with increasing spatial scale in age-class stands compared to uneven-aged stands. Combining forest stand simulation with scenario analyses is an exemplary method for testing the effect of silvicultural management alternatives on forest structure. This approach can later be connected to climate models considering long-term changes in growing conditions and support the planning of multifunctional forests.

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Vítková, Lucie, Dominik Saladin, and Marc Hanewinkel. "Financial viability of a fully simulated transformation from even-aged to uneven-aged stand structure in forests of different ages." Forestry: An International Journal of Forest Research 94, no. 4 (March 2, 2021): 479–91. http://dx.doi.org/10.1093/forestry/cpab005.

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Abstract For the first time, an economic analysis of a fully simulated forest transformation process from even-aged to uneven-aged stand structure using natural regeneration was performed using an individual tree growth simulator. A comparison to a ‘business as usual’ management approach (i.e. age-class scenario) was also made. Norway spruce (Picea abies (L.) Karst.)-dominated forests of different ages were selected for the simulation: forest at thinning stage (52 years; hereafter, ‘younger stand’) and a mature stand (95 years) to explore different starting points for the transformation. The harvested and remaining stand volume showed only little fluctuation over the course of the simulation period in the case of the transformation (uneven-aged) scenario. The age-class scenario, on the other hand, showed peaks and drops in the timber volume. The land expectation values at the end of transformation were higher (i = 1 or 2 per cent) or equal (i = 3 per cent) to those of the age-class scenario for the younger stand. The transformation of younger forests appears to be economically interesting (under interest rates above 2 per cent) as the early revenues of more intensive thinnings achieve an equilibrium growing stock well below the potential maximum growing stock of an even-aged stand. This suggests transformation management to be economically efficient under the given silvicultural and economic conditions. The transformation of mature stands was found to be less economically viable due to the lower holding values for the transformation (uneven-aged) scenario compared with the age-class scenario. However, the holding values of the younger stand were higher for all interest rates compared with the age-class scenario. This study concludes that transformation (uneven-aged) scenario yielded more economically viable silvicultural approach (in the case of younger forests) and a steadier trend in harvested and remaining timber volume showing no major fluctuations. Transformation approach also forms a better foundation where other ecosystem services can be built.

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Kutyavin, Ivan, Aleksey Manov, Andrey Osipov, and Mikhail Kuznetsov. "Stand Structure of Northern Taiga Pine Forests." Lesnoy Zhurnal (Forestry Journal), no. 2 (April 4, 2021): 86–105. http://dx.doi.org/10.37482/0536-1036-2021-2-86-105.

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In Northern taiga conditions pine forests occupy about 1.8 mln ha of the territory of the Komi Republic and are mainly represented by sphagnum, green-moss and lichen forest types. The studies were carried out at the Zelenoborsk Forest Station of the Institute of Biology of the Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences in green-moss and sphagnum pine forests developing at the site of fires and clearcuts. Tree layer has a mix composition with the predominance of pine trees and admixture of spruce, birch, larch and aspen. Pine stands form three types of age structure: conventionally evenaged; conventionally uneven-aged, represented by one generation; and stepped uneven-aged, consisting of two or three generations of pine trees. Trees left behind during clearcut and felling residuals at the cutting area by the burn method contribute to the formation of stands of stepped uneven-aged age structure. The variation coefficients of tree age are 5.8–10.8 % in pine forests with one generation and 39.7–45.6 % in forests with two or three generations. The number of generations and the type of age structure had no effect on the diameter and height of trees in the stand, which varied respectively within 25.2–49.5 % and 15.7–27.8 %. In pine forests developing after fires, the peak of pine settlement occur in the second or third decade, while in cutting areas, the maximum renewal occurs in the first or second decade after clearcuts. The amplitude of tree age fluctuations varies from 16 to 33 years in conventionally even-aged and conventionally uneven-aged forests developed after clearcuts and from 30 to 45 years in post-fire stands. In stepped uneven-aged stands tree age fluctuations changes from 120 to 167 years, and from 22 to 66 years in generations. The curves showing the distribution of trees by diameter in stands of pine trees had a left-handed shift, the asymmetry is represented by positive values and varies from 0.05 to 1.03. Trees of associate species are inferior in development, both in diameter and in height to pine trees of similar age. A close correlation between the diameter and height of trees in the stands was revealed. The relationship of age with diameter and height of trees varies from weak to significant at almost all of the sites studied. A close correlation between age and diameter was found in stepped uneven-aged pine forests (R = 0.79–0.96). The correlation between diameter and age increase with an increase in tree age fluctuations amplitude.

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Banaś, Jan, Stanisław Zięba, and Leszek Bujoczek. "An Example of Uneven-Aged Forest Management for Sustainable Timber Harvesting." Sustainability 10, no. 9 (September 15, 2018): 3305. http://dx.doi.org/10.3390/su10093305.

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This paper presents a system of uneven-aged forest management consistent with the principles of close-to-nature silviculture with treatments adopted to the requirements of individual tree stands, depending on their development phase, growing stock volume, DBH distribution and regeneration status. The study involves an experimental forest (property of the University of Agriculture in Cracow, Poland) with an area of 455.86 ha, located in the Western Carpathians. Data about stand characteristics and development processes, including regeneration, survival and removal, were obtained by measurements conducted at 10-year intervals on 413 permanent sample plots in the years 1976–2016, resulting in a total of four measurement periods. In the first period (1976–1986), harvesting intensity was low at 2.16 m3/ha/year but subsequently increased with the development of growing stock, higher volume increments and improved age and species structure, to finally reach 10.34 m3/ha/year in 2006–2016. The mean volume of timber harvested over the entire study period was 6.12 m3/ha/year, corresponding to 65.2% of the volume increment and 2.8% of the total growing stock. Management by the close-to-nature silviculture method had a positive impact on the forest characteristics. The improved species and age structure and the increased volume increment and growing stock translated into greater stand productivity without detriment to the implementation of non-timber forest functions.

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Remeš, J., and J. Kozel. "Structure, growth and increment of the stands in the course of stand transformation in the Klokočná Forest Range." Journal of Forest Science 52, No. 12 (January 9, 2012): 537–46. http://dx.doi.org/10.17221/4534-jfs.

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This paper deals with transformation of pure even-aged forest stands to uneven-aged irregular stands on an example of the Klokočná Forest Range. The fully operational management system according to principles of shelterwood or selection systems has been executed here since 1993. An investigation of this transformation process started in 1999 and it is focused on the places with more distinct structural differences. On the basis of research analysis, it is possible to consider about the permanent uneven-aged forest stands in future here. But for successful achievement of this goal it is necessary to continue this transformation step by step for a long time. The transformation is still at the beginning and its result depends on the effort and the forest management goal and the priority of the particular forest functions.

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Kelty, Matthew J., David B. Kittredge, Thom Kyker–Snowman, and Adrian D. Leighton. "The Conversion of Even-Aged Stands to Uneven-Aged Structure in Southern New England." Northern Journal of Applied Forestry 20, no. 3 (September 1, 2003): 109–16. http://dx.doi.org/10.1093/njaf/20.3.109.

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Abstract Partial cutting is common in mature even-aged stands in southern New England because the level of disturbance associated with even-aged regeneration methods is unacceptable to many private owners of small forest properties. This cutting often consists of high-grading, but foresters seeking an alternative generally turn to the selection method to begin the conversion of these stands to uneven-aged structure. However, the single-tree or small-group selection methods used may produce long-term results that are similar to high-grading in shifting stand composition toward shade tolerant species (many of which have low timber value). A review was made of the extensive research on the use of the selection method in northern New England and central Appalachian forest types, as well as of the limited research in the southern New England transition hardwood-white pine (Pinus strobus)-hemlock (Tsuga canadensis) type. Recent management experience in a Massachusetts public watershed forest was also reviewed. These provide general guidelines for using selection cutting in the region to regenerate species of a wide range in shade tolerance: (a) use patch selection (rather than single-tree or group selection) with a minimum patch size of 0.3 ac, and with understory as well as overstory trees removed in the patches; (b) use area control (proportion of stand to be harvested) rather than a target diameter distribution (q-value or other method) to regulate the stand cutting level. This approach is likely to be effective in meeting regeneration goals and in being logistically feasible, given the intensity of management possible on most of these properties. North. J. Appl. For. 20(3):109–116.

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Farnden, Craig. "Simulated conversion of unmanaged interior spruce-subalpine fir stands to a regulated uneven-aged structure." Forestry Chronicle 76, no. 3 (June 1, 2000): 465–74. http://dx.doi.org/10.5558/tfc76465-3.

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A localized version of the Forest Vegetation Simulator (FVS) individual tree growth model was developed to simulate stand level impacts under a variety of uneven-aged management regimes in old-growth interior spruce-subalpine fir forests near Prince George British Columbia. Options for using uneven-aged management to satisfy a range of management objectives were simulated using different sets of BDq regulation parameters, and by varying species composition and rules for reserve trees. The greatest timber yields were attained by promoting the highest possible spruce component, using high q ratios, low to moderate maximum diameters and 20 to 25 year cutting cycles, and allowing no reserves. Using strategies to promote stand structures maintaining some old-growth attributes resulted in much lower timber yields. Key words: white spruce, Engelmann spruce, subalpine fir, uneven-aged management, BDq regulation, simulated yield

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Pukkala, Timo, Erkki Lähde, Olavi Laiho, Kauko Salo, and Juha-Pekka Hotanen. "A multifunctional comparison of even-aged and uneven-aged forest management in a boreal region." Canadian Journal of Forest Research 41, no. 4 (April 2011): 851–62. http://dx.doi.org/10.1139/x11-009.

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The choice between even- and uneven-aged forest management is a topical issue as the negative impacts of clear-felling are being increasingly criticized and the profitability of even-aged management has been questioned. This study compared these management systems in spruce and pine stands in terms of timber, carbon, and bilberry benefits, all of which can be predicted with reasonable accuracy and quantified in terms of money. Management was optimized by maximizing the total net present value (NPV) of the three benefits in a steady-state situation. The currently recommended type of even-aged management was also included in the comparisons. Uneven-aged management was the best in terms of the total NPV and with respect to bilberry benefits (NPV of bilberry harvesting). It was also better than even-aged management in terms of timber benefits when the discount rate was more than 1%. The ranking was less clear in terms of carbon sequestration and discounted carbon benefits.

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Anderson, David J., and B. Bruce Bare. "A dynamic programming algorithm for optimization of uneven-aged forest stands." Canadian Journal of Forest Research 24, no. 9 (September 1, 1994): 1758–65. http://dx.doi.org/10.1139/x94-227.

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A deterministic dynamic programming formulation of the transition uneven-aged stand management problem is presented. Using a previously published northern hardwoods growth model, a forward recursive, discrete, two-state problem that maximizes the net present value of harvested trees at each stage is developed. State variables represent the total number of trees and the total basal area per acre. A neighborhood storage concept previously published is used to reduce the number of states considered at each stage. Two harvest allocation rules are used to assign the harvested basal area to individual diameter classes. Terminal end point conditions and stage to stage sustainability are not required. Results from four base runs of the model are presented and compared with previously published results. Each run produces significantly different optimal paths, with one showing a higher net present value than any previously published. Sensitivity runs illustrate the impact of changes in interest rates, width of neighborhood storage class, and initial conditions. Dynamic programming offers promise for analyzing uneven-aged stand management problems.

23

Loewenstein, Edward F., Paul S. Johnson, and Harold E. Garrett. "Age and diameter structure of a managed uneven-aged oak forest." Canadian Journal of Forest Research 30, no. 7 (July 1, 2000): 1060–70. http://dx.doi.org/10.1139/x00-036.

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We studied the age and diameter structure on one section (259 ha) of a 63 000-ha privately owned forest in the Ozark Highlands of Missouri. The forest has been managed using a partial cutting strategy since 1954. Because a majority of the trees predate current management practices, the existing stand structure is a function of not only the current silvicultural system and the dynamics of this ecosystem but also the initial stand conditions. To determine age structure and evaluate the relationship of diameter and age, a random sample of 600 oaks [Formula: see text]4 cm DBH were collected from ten 0.4-ha plots. Based on the test of a binomial proportion, the oak populations on 7 of the 10 plots were deemed uneven aged, two were deemed two aged, and one was even aged. DBH accounted for 40 (red oaks) to 62% (white oaks) of the variation in tree age. Although the overall diameter frequency distribution of oaks formed a reverse-J shape, the age-frequency distribution approximated a normal (bell-shaped) distribution. We show how this apparent inconsistency between diameter and age distributions can be an artifact of a minimum sampling diameter. Such a truncation of the sampled population reduces the observed frequency of trees in the younger age-classes, which in turn results in a bell-shaped rather than a reverse-J-shaped age-frequency distribution. Thus, the lack of a reverse- J-shaped age distribution should not be interpreted as a failure to sustain regeneration in an uneven-aged stand.

24

Chang, Sun Joseph, and Klaus V. Gadow. "Application of the generalized Faustmann model to uneven-aged forest management." Journal of Forest Economics 16, no. 4 (December 2010): 313–25. http://dx.doi.org/10.1016/j.jfe.2010.06.002.

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25

Zhang, Lianjun, Jeffrey H. Gove, Chuangmin Liu, and William B. Leak. "A finite mixture of two Weibull distributions for modeling the diameter distributions of rotated-sigmoid, uneven-aged stands." Canadian Journal of Forest Research 31, no. 9 (September 1, 2001): 1654–59. http://dx.doi.org/10.1139/x01-086.

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The rotated-sigmoid form is a characteristic of old-growth, uneven-aged forest stands caused by past disturbances such as cutting, fire, disease, and insect attacks. The diameter frequency distribution of the rotated-sigmoid form is bimodal with the second rounded peak in the midsized classes, rather than a smooth, steeply descending, monotonic curve. In this study a finite mixture of two Weibull distributions is used to describe the diameter distributions of the rotated-sigmoid, uneven-aged forest stands. Four example stands are selected to demonstrate model fitting and comparison. Compared with a single Weibull or negative exponential function, the finite finite mixture model is the only one that fits the diameter distributions well and produces root mean square error at least four times smaller than the other two. The results show that the finite mixture distribution is a better alternative method for modeling the diameter distribution of the rotated-sigmoid, uneven-aged forest stands.

26

Piazza, Adriana. "A Discussion of Vintage Optimization Models in Forest Economics." Forest Science 66, no. 4 (October 9, 2019): 469–77. http://dx.doi.org/10.1093/forsci/fxz056.

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Abstract Optimal forest harvesting is a problem that dates back many centuries. Modern forest-management needs models taking into account the relatively long rotation, the multiaged structure, the age-dependent timber content of trees, and the multiple services forests provide. Approaches to characterize the optimal management policy range from models that represent the forest by a unique state variable that can usually be solved analytically (i.e., models that consider forests composed by a unique even-aged stand or allow a uneven aged forest but only consider its total biomass), to much more sophisticated linear and integer programming harvest scheduling models. In this survey, we focus on dynamic optimization problems where the forest is represented with an age-class structure. These models present richer dynamics than one-variable models while preserving their analytic tractability to some extent.

27

Dong, Lingbo, Hongyang Wei, and Zhaogang Liu. "Optimizing Forest Spatial Structure with Neighborhood-Based Indices: Four Case Studies from Northeast China." Forests 11, no. 4 (April 7, 2020): 413. http://dx.doi.org/10.3390/f11040413.

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The fine-scale spatial patterns of trees and their interactions are of paramount importance for controlling the structure and function of forest ecosystems; however, few management techniques can be employed to adjust the structural characteristics of uneven-aged mixed forests. This research provides an accurate, efficient, and impersonal comprehensive thinning index (P-index) for selecting candidate harvesting trees; the index was proposed by weighting the commonly used quantitative indices with respect to stand fine-scale structures, competition status, tree vigor, and tree stability. The applications of the proposed P-index in evaluating and simulating the process of thinning operations were examined using four 1-ha mapped plots with different forest types, namely, natural secondary forest, natural pine-broadleaved mixed forest, natural larch-birch mixed forest, and natural oak forest, which were widely distributed across the Heilongjiang Province in Northeast China. The results indicated that the proposed P-index could effectively affect the structural differentiations between different forest types and alternative thinning intensities. The marginal benefits of alternative thinning intensities on the integrated forest structure indicated that removing 10% of the trees from the plots might be the optimal thinning intensity from the perspective of optimizing stand structure, in which the P-index values could be increased by approximately 5%–11% for the four tested plots. The main conclusion from this paper was that the proposed P-index could be used as a quantitative tool to manage uneven-aged mixed forests.

28

Coordes, Renke. "Waldbau und die Faustmann-Theorie." Schweizerische Zeitschrift fur Forstwesen 165, no. 10 (September 1, 2014): 321–28. http://dx.doi.org/10.3188/szf.2014.0321.

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Silviculture and the Faustmann theory The Faustmann model is the heart of a theory seeking to explain the management and evolution of forests as a social process. A weak spot of the theory, however, is its inability to model diverse silvicultural treatments of forest stands. Basically, the Faustmann model represents the management of trees in plantations alternating between clear-cuts and uniform regeneration. Probably the main limitation of the Faustmann model is its lack to address thinnings, which constitute a considerable part of the timber harvested, in particular in Central Europe. New developments within forestry economic theory, however, help interpreting the Faustmann model as a special case of a homogeneous and independent or else heterogeneous and interdependent forest management. With variable basic units and the introduction of interdependencies, any forest management regime can basically be analysed. Accordingly, thinnings in homogeneous stands might be understood as special cases of the management of mixed stands, which, in turn, represent a special case of uneven-aged management of stands and entire forests. First, the introduction of variable basic units and interdependencies is outlined, taking the example of thinnings. On this basis, the necessary adjustments and conclusions for mixed and uneven-aged forest stands are discussed, which finally allow for a general silvicultural model on an economic basis.

29

Fortin, Mathieu, Steve Bédard, Josianne DeBlois, and Sébastien Meunier. "Predicting individual tree mortality in northern hardwood stands under uneven-aged management in southern Québec, Canada." Annals of Forest Science 65, no. 2 (January 2008): 205. http://dx.doi.org/10.1051/forest:2007088.

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30

Duduman, Gabriel. "A forest management planning tool to create highly diverse uneven-aged stands." Forestry: An International Journal of Forest Research 84, no. 3 (May 26, 2011): 301–14. http://dx.doi.org/10.1093/forestry/cpr014.

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31

Lohmander, P., and S. Mohammadi Limaei. "Optimal Continuous Cover Forest Management in an Uneven-Aged Forest in the North of Iran." Journal of Applied Sciences 8, no. 11 (May 15, 2008): 1995–2007. http://dx.doi.org/10.3923/jas.2008.1995.2007.

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32

Lussier, Jean-Martin. "Changing our mental model from growing volume to producing value: The case of uneven-aged hardwood management." Forestry Chronicle 85, no. 3 (June 1, 2009): 382–86. http://dx.doi.org/10.5558/tfc85382-3.

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The selection system is a common management system in uneven-aged tolerant hardwoods stands in Crown forests of eastern Canada. This silvicultural system aims to produce a sustained yield of products and services at the stand level, using frequent partial cuttings that harvest the mature and valuable portion of the forest, while tending the rest of the stand to increase its productivity and value for future cuttings. Current practices involve the use of empirical partial cutting guides to decide the number of trees to both harvest and maintain at each cutting cycle, typically to maximize longterm sawlog and veneer production. This paper demonstrates that by replacing this objective function with the maximization of the net value of the harvest for the whole value chain by using a simple mathematical optimization model, forest management can be greatly improved in terms of profitability. Nevertheless, further developments are needed for improving forest management optimization models in order to better balance short-term profitability and long-term ecological, economic and societal objectives. Key words: Selection system, hardwoods, uneven-aged silviculture, optimization, economic, value chain, profitability, steering treatment

33

Niese, Jeffrey Neal, and Terry F. Strong. "Economic and tree diversity trade-offs in managed northern hardwoods." Canadian Journal of Forest Research 22, no. 11 (November 1, 1992): 1807–13. http://dx.doi.org/10.1139/x92-236.

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Forest ecologists have long believed that greater tree species diversity in hardwood forests reduces biological risk, but researchers have not yet linked diversification with economic returns for managed hardwood forests. This paper shows how management of northern hardwood forests affects tree species diversity and economic returns. Shannon's index is used to measure regeneration diversity for eight even- and uneven-aged cutting methods from a 40-year study on the Argonne Experimental Forest. These indices of tree species diversity are compared with the potential economic returns for the research sites.

34

Gill, Kyle G., Anthony W. D’Amato, and Shawn Fraver. "Multiple developmental pathways for range-margin Pinus banksiana forests." Canadian Journal of Forest Research 46, no. 2 (February 2016): 200–214. http://dx.doi.org/10.1139/cjfr-2015-0321.

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Empirical knowledge of forest structure and development in early successional and range-margin populations is often lacking, limiting our ability to effectively model and manage these forests. Such is the case for jack pine (Pinus banksiana Lamb.) in central Minnesota, USA, where it reaches its southwestern range limit. Our objective was to quantify this population’s historical range of variability of structural conditions and developmental pathways. We collected structural, spatial, and dendrochronological data on 0.25 ha plots from 10 jack pine dominated sites that initiated and developed outside of active management. Our results revealed a broad range of structural characteristics and developmental pathways, including rapid and protracted recruitment windows (5–50 years), with subsequent even- and uneven-aged structures, and random and clumped stem spatial arrangements. As such, these mature, early successional forests often displayed a degree of complexity more typically associated with old-growth forests. Our findings suggest that this population, like other southern range-margin populations with mostly nonserotinous cones, historically followed a variety of stand development pathways and did not solely follow the rapid establishment, even-aged pathway often attributed to this forest type. We suggest that even- and uneven-aged silvicultural systems should be used to reflect this historical range of developmental pathways and to increase resilience and adaptability.

35

Kant, Shashi. "The marginal cost of structural diversity of mixed uneven-aged hard maple forests." Canadian Journal of Forest Research 32, no. 4 (April 1, 2002): 616–28. http://dx.doi.org/10.1139/x02-001.

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Theoretical concepts pertaining to the marginal cost (MC) of the structural diversity of a forest stand are developed. A matrix growth model is estimated for mixed uneven-aged forest stands of hard maple (Acer saccharum Marsh.) from southern Ontario. The estimated growth model is used to derive the MC equations for the Shannon and the Simpson indices of total structural diversity (TSD), species diversity (SD), and tree-size diversity (TD). The effects of exclusion and inclusion of the opportunity cost (OC) on the MC of the TSD are compared. The contributions of SD and TD to the MC of the TSD are disaggregated. The MCs of TSD, SD, and TD for the Shannon and the Simpson indices are iso-elastic. The elasticity of the MC of the TSD for the inclusion of OC is greater than the elasticity of MC of the TSD for the exclusion of OC. The elasticities of MC of TSD, SD, and TD for the Shannon index are greater than the elasticities of MC of TSD, SD, and TD, respectively, for the Simpson index. The elasticities of MC of SD are smaller than the elasticities of MC of TD, for both indices. However, these results are specific to the hard maple forests of southern Ontario and cannot be generalized. Some general features of MC equations of structural diversity are discussed.

36

Kellomäki, Seppo, Hannu Väisänen, Miko U. F. Kirschbaum, Sara Kirsikka-Aho, and Heli Peltola. "Effects of different management options of Norway spruce on radiative forcing through changes in carbon stocks and albedo." Forestry: An International Journal of Forest Research 94, no. 4 (March 16, 2021): 588–97. http://dx.doi.org/10.1093/forestry/cpab010.

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Abstract Norway spruce (Picea abies Karst. (L.)) in the boreal zone can be managed as even-aged or uneven-aged stands, or be grown with no management at all. Here, we investigated how these management options affect carbon dynamics, particularly the carbon stocks in the forest ecosystem (trees and soil), and albedo, and their combined effect on radiative forcing compared to a reference case, clear-cut site before planting seedlings. This allowed us to assess the potential of different management regimes to mitigate global warming. We ran long-term simulations under the current climate on a sub-mesic site in central Finland (62oN) using an eco-physiological forest-ecosystem model. Compared to even-aged management, no management (old-growth forest) increased ecosystem carbon stocks by 47 per cent and decreased albedo by 15 per cent, whereas uneven-aged management reduced ecosystem carbon stocks by 16 per cent and increased albedo by 10 per cent. Only the no management option resulted in a significant net cooling effect whereas for even-aged and uneven-aged management, the opposing effects of changes in albedo and carbon stocks largely cancelled each other with little remaining net effect. On the other hand, the latter one even made a small net warming contribution. Overall, maintaining higher ecosystem carbon stocks implied the larger cooling benefits. This was evident even though lower albedo enhanced radiation absorption, and thus warming. Increasing use of the no management option by forest owners may require proper incentives such as compensation for lost harvest incomes.

37

Chatterjee, A., G. F. Vance, and D. B. Tinker. "Carbon pools of managed and unmanaged stands of ponderosa and lodgepole pine forests in Wyoming." Canadian Journal of Forest Research 39, no. 10 (October 2009): 1893–900. http://dx.doi.org/10.1139/x09-112.

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Forest management practices can have a significant effect on above- and below-ground carbon (C) pools. To better understand the distribution of forest C pools, we evaluated representative forest stands within two dominant Wyoming forest types to assess differences resulting from management practices that have occurred over several decades. Study sites included four ponderosa pine ( Pinus ponderosa Douglas ex Lawson & C.Lawson) treatments (100-year-old unmanaged, 46-year-old even-aged, 110-year-old uneven-aged, and 90-year-old intensively harvested) and two lodgepole pine ( Pinus contorta Engelm. var. latifolia (Engelm. ex Wats.) Critchfield) treatments (145-year-old unmanaged and 45-year-old even-aged). Comparisons of aboveground C pools revealed that distributions of live and dead biomass C pools were different between unmanaged and managed stands; however, belowground soil C pools were similar among stands within the two forest types. Overall, unmanaged stands of both forest types had higher total ecosystem C pools (249 and 247 Mg C·ha–1 for ponderosa and lodgepole pine, respectively) compared with managed stands (ponderosa pine: even-aged, 164 Mg C·ha–1; uneven-aged, 170 Mg C·ha–1; intensively harvested, 200 Mg C·ha–1; and lodgepole pine even-aged, 117 Mg C·ha–1). Our results indicate timber harvesting has a major influence on total ecosystem C pools by reducing live tree biomass.

38

Kulla, L., J. Tutka, and R. Marušák. "Forest yield index and its applicability to the assessment of future forest yields." Journal of Forest Science 55, No. 1 (February 3, 2009): 41–50. http://dx.doi.org/10.17221/45/2008-jfs.

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The paper suggests and examines a simplified relative indicator of forest production, with special regard to possibilities of its use in projecting future forests. Forest yield index (<I>I</I><sub>Y</sub>), based on an economic parameter “value of final cutting yield” was proposed, and examined in the model territory of Kysuce in north-western Slovakia. The current values of final cutting yield, dependent on tree species, site index and the length of rotation period served as a basis for the assessment of expected yields. The possibilities and limitations of index applicability in long-term strategic forest management decision-making are discussed, considering the uncertainty of ecological and economic conditions during the long forest production cycle, as well as the complexity of tree species growth and production in the mixed forests, uneven aged forests and forests under climate change.

39

Parsakhoo, A., and S. A. Hosseini. "Forest Damage Caused by Earth Working Operations in Uneven Aged Deciduous Stands." Research Journal of Environmental Sciences 3, no. 6 (June 1, 2009): 631–39. http://dx.doi.org/10.3923/rjes.2009.631.639.

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40

Buongiorno, Joseph. "Quantifying the implications of transformation from even to uneven-aged forest stands." Forest Ecology and Management 151, no. 1-3 (October 2001): 121–32. http://dx.doi.org/10.1016/s0378-1127(00)00702-7.

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41

López Torres, Ignacio, and Carmen Fullana Belda. "Dimensionless numbers for the sustainable harvesting of a monospecific uneven-aged forest." Canadian Journal of Forest Research 45, no. 11 (November 2015): 1535–45. http://dx.doi.org/10.1139/cjfr-2015-0140.

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This study proposes a simple and direct method based on dimensionless numbers to provide reliable approximations of the population growth rate, the “sustainable/stable” harvest rate, the proportion of trees that has to remain unharvested to retain the stable diameter distribution, and the stable diameter distribution of a forest stand. Those numbers, obtained under conditions of stable equilibrium from a matrix model, could also serve to estimate boundaries between sustainable and unsustainable harvesting. To exemplify and test the results, the model uses data from uneven-aged managed Pinus nigra Arnold stands, considering three levels of tree diameter growth, six levels of basal area, and 33 levels of recruitment, creating a total of 594 planning scenarios. The best approximation of all the variables observed occurred in any case for the scenarios with the lowest level of diameter growth, the lowest level of basal area, and the highest recruitment level. Furthermore, the study reveals the existence of a strong positive linear correlation between those variables and their respective approximations, as well as a small distance between the stable diameter distribution of the stand and its approximation. Finally, we incorporate natural disturbances into the dimensionless numbers and criteria.

42

CAMERON, A. D., and G. JANO. "DEFINING THE EQUILIBRIUM CONDITION IN A MIXEDSPECIES UNEVEN-AGED FOREST IN SCOTLAND." Applied Ecology and Environmental Research 16, no. 5 (2018): 7327–44. http://dx.doi.org/10.15666/aeer/1605_73277344.

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43

Jacobsen, Jette Bredahl, and Finn Helles. "Adaptive and nonadaptive harvesting in uneven-aged beech forest with stochastic prices." Forest Policy and Economics 8, no. 3 (April 2006): 223–38. http://dx.doi.org/10.1016/j.forpol.2004.06.004.

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44

Joelsson, Klara, Joakim Hjältén, Timothy Work, Heloise Gibb, Jean-Michel Roberge, and Therese Löfroth. "Uneven-aged silviculture can reduce negative effects of forest management on beetles." Forest Ecology and Management 391 (May 2017): 436–45. http://dx.doi.org/10.1016/j.foreco.2017.02.006.

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45

Kellomäki, S., H. Strandman, and H. Peltola. "Effects of even-aged and uneven-aged management on carbon dynamics and timber yield in boreal Norway spruce stands: a forest ecosystem model approach." Forestry: An International Journal of Forest Research 92, no. 5 (June 28, 2019): 635–47. http://dx.doi.org/10.1093/forestry/cpz040.

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Abstract We used a gap-type forest ecosystem model to study how even- and uneven-aged management affected the carbon dynamics and timber production in boreal Norway spruce stands. In business-as-usual management, the intensity of thinnings (from below) and single-tree selective cuttings followed those recommended for even-aged (BT) and uneven-aged management (BSC) in practical forestry in Finland. Moreover, higher or lower basal area thresholds, and shorter or longer production cycles, were used in simulations. We found that, the mean annual carbon uptake, volume growth, and carbon stock in trees and harvested timber, were nearly the same under even-aged (BT) and uneven-aged (BSC) management, when assuming full seed crop in latter one. However, the carbon stock in the soil and ecosystem and the mean annual net ecosystem exchange were slightly smaller under BT. The carbon retention time was longer under BSC. The net present value (NPV with interest rate of 3 per cent) of timber production was clearly lower under BT, when the calculation was initiated at planting on clear-cutting area, in opposite to when initiating calculation a few years before the second thinning. Higher basal area thresholds and longer production cycles increased carbon stocks, carbon retention and timber yield, regardless of management system. On the other hand, the results of uneven-aged management (BSC) were very sensitive to the success of natural regeneration and ingrowth of seedlings, as a reduction of the seed crop by 25–75 per cent from the full seed crop decreases the volume growth by 44–74 per cent and timber yield up to 46 per cent.

46

Bergeron, Yves, and Nicole J. Fenton. "Boreal forests of eastern Canada revisited: old growth, nonfire disturbances, forest succession, and biodiversity." Botany 90, no. 6 (June 2012): 509–23. http://dx.doi.org/10.1139/b2012-034.

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Boreal forests have commonly been described as dominated by monospecific postfire stands that are reburnt well before other ecological process than those occurring immediately after fire can take place. Research undertaken over the last 30 years has given us a very different perspective of the complexity of Canadian boreal forests. Old-growth forests are common and their development is controlled by nonfire disturbances. Consequently, monospecific even-aged stands can develop towards more diversified uneven-aged stands with increasing time since fire. This complex disturbance regime, including both fire and nonfire disturbances, is partially responsible for a higher than expected biodiversity (e.g., understory) in these forests. The dominating forest management model in Canadian boreal forests, based on clear-cut harvesting and regeneration of short rotation even-aged stands, does not reflect the complexities of the disturbance–succession cycle observed in Canadian natural boreal forests.

47

Lilieholm, R. J., L. S. Davis, R. C. Heald, and S. P. Holmen. "Effects of Single Tree Selection Harvests on Stand Structure, Species Composition, and Understory Tree Growth in a Sierra Mixed Conifer Forest." Western Journal of Applied Forestry 5, no. 2 (April 1, 1990): 43–47. http://dx.doi.org/10.1093/wjaf/5.2.43.

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Abstract After 20-28 years of single tree selection harvests in initially irregular even-aged stands, stand structure is approaching a target uneven-aged diameter distribution. Seedling stocking in managed stands is nearly three times greater than that of unmanaged stands. Although shade-tolerant species comprise the bulk of most size classes in both managed and unmanaged stands, selection harvests have resulted in adequate quantities of seedlings from all five conifer species, including pines. In managed stands, current small-tree stocking and rates of growth appear adequate to sustain single tree selection harvests over much of a 90-year growth simulation. Simulated peak growth rates of uneven-aged stands compare favorably with actual and anticipated yields from the forest's uneven- and even-aged stands. West. J. Appl. For. 5(2):43-47, April 1990.

48

Lefort, P., B. Harvey, J. Parton, and G. KM Smith. "Synthesizing knowledge of the Claybelt to promote sustainable forest management." Forestry Chronicle 78, no. 5 (October 1, 2002): 665–71. http://dx.doi.org/10.5558/tfc78665-5.

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A review of the scientific literature relevant to the Claybelt region was undertaken under the initiative of Lake Abitibi Model Forest (LAMF) and in collaboration with the Canadian Forest Service, the Ontario and Quebec Ministries of Natural Resources and the NSERC-UQAT-UQAM (Natural Sciences and Engineering Research Council Université du Québec en Abitibi-Témiscamingue Université du Québec à Montréal) Industrial Chair in Sustainable forest Management. The objective was to synthesize this information in order to develop better forestry practices and identify knowledge and research gaps. Forestry-related knowledge was gathered on six broad topics: i) natural disturbances, ii) forest ecosystems, iii) past and present forest practices, iv) biological diversity, v) forest management and vi) examples of current applications of natural disturbance-based forest management. The work allowed us to synthesize a large body of knowledge into one publication that will be a useful reference for foresters in both provinces. Key words: biodiversity, Claybelt, even-aged/uneven-aged forests, fire, silvicultural practices

49

Kulla, Ladislav, Michal Bošeľa, Vlastimil Murgaš, Joerg Roessiger, and Vladimír Šebeň. "Reconstructing past forest status using inventory and tree ring data to support uneven-aged forest management." Central European Forestry Journal 63, no. 4 (September 26, 2017): 203–11. http://dx.doi.org/10.1515/forj-2017-0022.

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Abstract The decision to change forest management system from the traditional even-aged to the selection one based on statistical inventory is often limited by a missing previous inventory. To avoid this issue, we used available forest inventory data from ca 2 000 ha of mixed uneven-aged beech-fir-spruce-pine forest and tree ring data from 831 trees to reconstruct forest status from one decade ago. For this purpose, we have created three sets of species-specific models: 1) diameter-stump models to reconstruct the diameter of missing trees, 2) diameter-increment models based on tree ring data to estimate past diameters, and 3) height-diameter models to estimate past tree heights. This approach has allowed us to completely reconstruct the state of the forest as it was ten years ago and use the results as a substitution for a previously missing inventory.

50

Schall, Peter, Martin M. Gossner, Steffi Heinrichs, Markus Fischer, Steffen Boch, Daniel Prati, Kirsten Jung, et al. "The impact of even-aged and uneven-aged forest management on regional biodiversity of multiple taxa in European beech forests." Journal of Applied Ecology 55, no. 1 (June 30, 2017): 267–78. http://dx.doi.org/10.1111/1365-2664.12950.

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