Dimensionless numbers for the sustainable harvesting of a monospecific uneven-aged forest

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.

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Deriving Tree Size Distributions of Tropical Forests from Lidar

Remote Sensing ◽

10.3390/rs13010131 ◽

2021 ◽

Vol 13 (1) ◽

pp. 131

Author(s):

Franziska Taubert ◽

Rico Fischer ◽

Nikolai Knapp ◽

Andreas Huth

Keyword(s):

Size Distribution ◽

Spatial Scales ◽

Basal Area ◽

Tree Height ◽

Tree Size ◽

Diameter Distribution ◽

Forest Inventories ◽

Allometric Relations ◽

Lidar Measurements ◽

Derived Data

Remote sensing is an important tool to monitor forests to rapidly detect changes due to global change and other threats. Here, we present a novel methodology to infer the tree size distribution from light detection and ranging (lidar) measurements. Our approach is based on a theoretical leaf–tree matrix derived from allometric relations of trees. Using the leaf–tree matrix, we compute the tree size distribution that fit to the observed leaf area density profile via lidar. To validate our approach, we analyzed the stem diameter distribution of a tropical forest in Panama and compared lidar-derived data with data from forest inventories at different spatial scales (0.04 ha to 50 ha). Our estimates had a high accuracy at scales above 1 ha (1 ha: root mean square error (RMSE) 67.6 trees ha−1/normalized RMSE 18.8%/R² 0.76; 50 ha: 22.8 trees ha−1/6.2%/0.89). Estimates for smaller scales (1-ha to 0.04-ha) were reliably for forests with low height, dense canopy or low tree height heterogeneity. Estimates for the basal area were accurate at the 1-ha scale (RMSE 4.7 tree ha−1, bias 0.8 m² ha−1) but less accurate at smaller scales. Our methodology, further tested at additional sites, provides a useful approach to determine the tree size distribution of forests by integrating information on tree allometries.

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Deriving Tree Diameter Growth and Probability of Survival Equations from Successive Diameter Distributions

Forest Science ◽

10.1093/forestscience/54.1.31 ◽

2008 ◽

Vol 54 (1) ◽

pp. 31-35

Author(s):

Thomas G. Matney ◽

Emily B. Schultz

Keyword(s):

General Procedure ◽

Growth And Yield ◽

Diameter Distribution ◽

Diameter Growth ◽

Individual Tree ◽

Statistical Probability ◽

Growth And Survival ◽

Tree Diameter ◽

Growth And Yield Models ◽

Diameter Distributions

Abstract Many growth and yield models have used statistical probability distributions to estimate the diameter distribution of a stand at any age. Equations for approximating individual tree diameter growth and survival probabilities from dbh can be derived from these models. A general procedure for determining the functions is discussed and illustrated using a loblolly pine spacing study. The results from the spacing study show that it is possible to define tree diameter growth and survival probability functions from diameter distributions with an accuracy sufficient to obtain a link between the individual tree and diameter growth and yield models.

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TREE DIAMETER GROWTH FOLLOWING SILVICULTURAL TREATMENTS IN A SEMI-DECIDUOUS SECONDARY FOREST IN CENTRAL BRAZIL

CERNE ◽

10.1590/01047760201521011204 ◽

2015 ◽

Vol 21 (1) ◽

pp. 117-123 ◽

Cited By ~ 6

Author(s):

Fábio Venturoli ◽

Augusto César Franco ◽

Christopher William Fagg

Keyword(s):

Radial Growth ◽

Deciduous Forest ◽

Secondary Forest ◽

Basal Area ◽

Diameter Growth ◽

Annual Increment ◽

Tree Diameter ◽

Central Brazil ◽

Silvicultural Treatments ◽

Timber Market

In the Cerrado biome of Brazil, savannas and dry forests are intimately linked and form mosaics. These forests are composed of species of high commercial value, well accepted in the timber market, which causes intensive deforestation on the remaining vegetation. Thus, the management of these forests is an important alternative to reduce deforestation in the remaining vegetation. The objective of this study was to analyze the response of tree species in relation to silvicultural treatments of competition and liana cutting in a semi-deciduous forest in Central Brazil. The results showed that community basal area increased 24% over 4.8 years and the median periodic annual increment in diameter was about 20% higher in plots with silvicultural treatments: 2.9 mm.yr-1 in the control compared to 3.2 mm.yr-1 to 3.6 mm.yr-1 between treatments. This study demonstrated that it is possible to increase the rates of radial growth through silvicultural techniques.

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Influence of canopy tree size on stand basal area may reflect uncoupling of crown expansion and trunk diameter growth

Austral Ecology ◽

10.1046/j.1442-9993.2003.01279.x ◽

2003 ◽

Vol 28 (2) ◽

pp. 216-218 ◽

Cited By ~ 9

Author(s):

Christopher H. Lusk ◽

Carolina Jara ◽

Teresa Parada

Keyword(s):

Basal Area ◽

Tree Size ◽

Diameter Growth ◽

Trunk Diameter ◽

Canopy Tree ◽

Stand Basal Area

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Thinning Response and Potential Basal Area in a Mixed Sub-humid Low-elevation Oak-Hornbeam Forest

10.21203/rs.3.rs-698917/v1 ◽

2021 ◽

Author(s):

Mathias Neumann ◽

Hubert Hasenauer

Keyword(s):

Stand Structure ◽

Basal Area ◽

Climatic Conditions ◽

Diameter Distribution ◽

Stem Density ◽

Growing Stock ◽

A Site ◽

Water Nutrients ◽

Related Mortality

Abstract Competition for resources (light, water, nutrients, etc.) limits the size and abundance of alive trees a site can support. This carrying capacity determines the potential carbon sequestration in alive trees as well as the maximum growing stock. Lower stocking through thinning can change growth and mortality. We were interested in the relations between stand structure, increment and mortality using a long-unmanaged oak-hornbeam forest near Vienna, Austria, as case study. We expected lower increment for heavy thinned compared to unmanaged stands. We tested the thinning response using three permanent growth plots, whereas two were thinned (50% and 70% basal area removed) and one remained unmanaged. We calculated stand structure (basal area, stem density, diameter distribution) and increment and mortality of single trees. The heavy thinned stand had over ten years similar increment as the moderate thinned and unthinned stands. Basal area of the unthinned stand remained constant and stem density decreased due to competition-related mortality. The studied oak-hornbeam stands responded well even to late and heavy thinning suggesting a broad “plateau” of stocking and increment for these forest types. Lower stem density for thinned stands lead to much larger tree increment of single trees, compared to the unthinned reference. The findings of this study need verification for other soil and climatic conditions.

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Long-Term Effects of Early Pruning and Thinning Treatments on Growth of Natural Longleaf Pine

Southern Journal of Applied Forestry ◽

10.1093/sjaf/4.2.77 ◽

1980 ◽

Vol 4 (2) ◽

pp. 77-79

Author(s):

Robert C. Sparks ◽

Norwin E. Linnartz ◽

Harold E. Harris

Keyword(s):

Longleaf Pine ◽

Basal Area ◽

Pinus Palustris ◽

Diameter Growth ◽

Stocking Rate ◽

Long Term Effects ◽

Natural Stand ◽

Stocking Rates ◽

Pruning Intensity

Abstract Pruning and thinning a young natural stand of longleaf pine (Pinus palustris Mill.) in southwest Louisiana had little influence on height. However, diameter growth was reduced substantially as pruning intensity or stocking rate increased up to 25-percent live crown and 200 stems per acre, respectively. Improved diameter growth at lower stocking rates was not sufficient to equal the total basal area increment of 200 trees per acre.

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Conversion of Pinus nigra Plantations with Natural Regeneration in the Slovenian Karst: The Importance of Intermediate, Gradually Formed Canopy Gaps

Forests ◽

10.3390/f10121136 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1136

Author(s):

Jurij Diaci ◽

Tomaž Adamič ◽

Andrej Rozman ◽

Gal Fidej ◽

Dušan Roženbergar

Keyword(s):

Natural Regeneration ◽

Soil Depth ◽

Pinus Nigra ◽

Quercus Petraea ◽

Summer Drought ◽

Natural Disturbances ◽

Site Factors ◽

Insect Infestations ◽

One Year ◽

Ostrya Carpinifolia

Since the mid-19th century, Pinus nigra plantations have played a key role in the restoration of degraded European landscapes. Nowadays, these plantations are aging and prone to natural disturbances, insect infestations, and diseases. For their successful gradual conversion, knowledge of optimal gap spatiotemporal dynamics is crucial. We studied herb and natural regeneration patterns along with site factors on 477 subplots within 44 plots distributed over four stand types: closed stand (14% diffuse light), open stand (21%), gap edge (23%), and gap (57%). Despite the abundant Quercus petraea, Q. cerris, and Q. pubescens mast year, no one-year seedlings were recorded, which is likely due to the summer drought. Short seedlings (h < 20 cm) of Quercus sp., Fraxinus ornus and Ostrya carpinifolia were more successful within closed stands. Short Quercus seedlings were positively associated with soil depth and negatively associated with soil nutrients, distance to seed trees, and Sesleria autumnalis coverage. Taller Quercus seedlings required more light than both of its strongest competitors and were positively related to humid soils and less rocky sites. Ungulate overbrowsing significantly impeded natural regeneration. The results indicate a satisfactory Quercus density for conversion and the importance of advanced regeneration, which should be gradually, but persistently, released by progressively widening gaps.

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Disturbance history affects dead wood abundance in Newfoundland boreal forests

Canadian Journal of Forest Research ◽

10.1139/x06-195 ◽

2006 ◽

Vol 36 (12) ◽

pp. 3194-3208 ◽

Cited By ~ 29

Author(s):

Martin T Moroni

Keyword(s):

Boreal Forests ◽

Dead Wood ◽

Black Spruce ◽

Woody Debris ◽

Abies Balsamea ◽

Natural Disturbance ◽

Diameter Distribution ◽

Natural Disturbances ◽

A Minor ◽

Almost All

Dead wood (dead standing tree (snag), woody debris (WD), buried wood, and stump) abundance was estimated in Newfoundland balsam fir (Abies balsamea (L.) Mill.) and black spruce (Picea mariana (Mill.) BSP) forests regrown following natural and anthropogenic disturbances. Although harvesting left few snags standing, natural disturbances generated many snags. Most were still standing 2 years after natural disturbance, but almost all had fallen after 33–34 years. Snag abundance then increased in stands aged 86–109 years. Natural disturbances generated little WD 0–2 years following disturbance. Harvesting, however, immediately generated large amounts of WD. Thirty-two to forty-one years following disturbance, most harvesting slash had decomposed, but naturally disturbed sites had large amounts of WD from collapsed snags. Harvested sites contained less WD 32–72 years following disturbance than naturally disturbed sites. Amounts of WD in black spruce regrown following harvesting and fire converged 63–72 years following disturbance, despite significant initial differences in WD quantities, diameter distribution, and decay classes. Abundance of WD increased from sites regrown 32–72 years following disturbance to older sites. Precommercial thinning had a minor impact on dead wood stocks. Stumps contained minor biomass. Buried wood and WD biomass were equivalent at some sites.

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INVESTIGATING SILVICULTURAL CHARACTERISTICS OF YEW (TAXUS BACCATA L.) STAND USING FULL-CALLIPERING IN NORTHERN FORESTS OF IRAN

International Journal of Biomathematics ◽

10.1142/s1793524512500672 ◽

2013 ◽

Vol 06 (01) ◽

pp. 1250067 ◽

Cited By ~ 1

Author(s):

MIR MOZAFFAR FALLAHCHAI ◽

SEYED ARMIN HASHEMI ◽

GASEM RAHANJAM

Keyword(s):

Distribution Curve ◽

Basal Area ◽

Diameter Distribution ◽

Maximum Height ◽

Taxus Baccata ◽

Height Distribution ◽

Annual Increment ◽

Restricted Area ◽

Northern Forests ◽

Low Rate

In this research, some of site and silvicultural characteristics of Yew stand in northern forests of Iran was studied. For this purpose, compartment number 16 of district 4 Shir-ghalaye was selected. According to research purposes, stands with an area of 20 ha were chosen in center of the compartment and was separated from map. Due to restricted area of region and according to few number of Yew trees in the stand, the full-callipering method was conducted for measuring quantitative and qualitative characteristics. In the stand diameter at breast height (D.B.H.), height and canopy diameter of all Yew trees were measured. The results showed that the diameter distribution curve and height distribution curve of Yew trees were similar to even-age forests curve. But according to average annual increment, mixture type of Yew trees in stand, diameter distribution of other species and low rate regeneration of Yew, it can be concluded that the studied Yew stand, is an uneven-age stand and because of low rate regeneration in previous years the number of young Yew trees were reduced and even-age forest curve was formed subsequently. The maximum height and diameter of Yew trees were recorded 26.8 m and 112 cm, respectively. Also, the number of trees per hectare and basal area per hectare of Yew trees were calculated 14.55 and 3.23 m2 respectively.

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