scholarly journals A Structure Analysis for Ecological Management of Moist Tropical Forests

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Adrien Djomo Njepang
Keyword(s):  
Species Composition ◽  
Stand Structure ◽  
Human Impacts ◽  
Basal Area ◽  
Diameter Distribution ◽  
Ecological Management ◽  
Natural Forests ◽  
Forest Types ◽  
Moist Forest ◽  
Commercial Species

Human interventions alter stand structure, species composition, and regeneration capacity of the forest. There is no enough information on how different management systems affect the forest structure. The main objective of this study was to analyze the differences on stand structure and species composition caused by different logging intensities. The study was conducted in a lowland evergreen moist forest of 22 000 ha in Cameroon. The forest was subdivided into three forest types with different human impacts:2-Logged,1-Logged, andUnlogged. The diameter corresponding to mean basal area of stems of2-Logged(31.8 cm,N=369) was almost equal to that ofUnlogged(30.1 cm,N=496).1-Loggedhad a lower diameter of 27.7 cm,N=530. In the three forest types, the diameter distribution followed the inverse J-shaped curve frequently observed in natural forests. The stand basal area increased from 29.4 m2/ha in2-Logged, to 32 m2/ha in1-Logged, and to 35.3 m2/ha inUnlogged. These results indicated that logging affected natural regeneration in2-Logged. Above 60 cm dbh, the logging effect was not visible. On 103 tree species found in the sample forest, only nine were classified as harvestable commercial species.

Changes in landscape composition and stand structure from 1945–2002 on an industrial forest in New Brunswick, Canada

2005 ◽  
Vol 35 (8) ◽  
pp. 1965-1977 ◽  
Author(s):  
David A Etheridge ◽  
David A MacLean ◽  
Robert G Wagner ◽  
Jeremy S Wilson
Keyword(s):  
Species Composition ◽  
New Brunswick ◽  
Stand Structure ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Basal Area ◽  
Landscape Composition ◽  
Balsam Fir ◽  
Forest Types ◽  
Industrial Forest

Detailed 1944–1947 cruise data and maps were used to compare species composition, age-class distribution, and stand structure between 1945 and 2002, for a 190 000 ha industrial forest in New Brunswick, Canada. Softwood forest area in 1945 and 2002 was similar, at 40% and 42%, respectively, but mixed hardwood–softwood decreased from 37% to 18%, and hardwood increased from 10% to 25%. Forest management from 1945 to 2002 resulted in the forest (1) becoming younger, with 86% of the trees >70 years old in 2002 versus 44% in 1945, (2) becoming denser, with 100–300 more stems per hectare and 4–7 m2/ha more basal area in 2002, and (3) having less balsam fir (Abies balsamea (L.) Mill.) — 31%–66% in 1945 versus 4%–38% in 2002 of basal area for stands with >30% softwood. Management reduced balsam fir to lower mortality associated with spruce budworm (Choristoneura fumiferana (Clem.)) outbreaks. The area of old (≥70 years old, with ≥10 trees/ha ≥30 cm DBH) and large (≥70 years old, with ≥5 trees/ha ≥45 cm DBH) spruce-fir and mixedwood wildlife habitats decreased from 112 600 and 55 200 ha in 1945 to 8200 and 7200 in 2002, respectively, while hardwood habitat increased from 22 800 to 71 500 ha. Management increased timber production while maintaining similar softwood species composition, but altered age structure and areas of mixedwood and hardwood forest types.

Langfristige Entwicklung von zwei Waldgesellschaften im Białowieża-Urwald

2008 ◽  
Vol 159 (4) ◽  
pp. 80-90 ◽  
Author(s):  
Bogdan Brzeziecki ◽  
Feliks Eugeniusz Bernadzki
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
Stand Structure ◽  
Temporal Dynamics ◽  
Structural Parameters ◽  
Forest Communities ◽  
Natural Forests ◽  
Tree Species Composition ◽  
Strong Trend ◽  
Long Term Study

The results of a long-term study on the natural forest dynamics of two forest communities on one sample plot within the Białowieża National Park in Poland are presented. The two investigated forest communities consist of the Pino-Quercetum and the Tilio-Carpinetum type with the major tree species Pinus sylvestris, Picea abies, Betula sp., Quercus robur, Tilia cordata and Carpinus betulus. The results reveal strong temporal dynamics of both forest communities since 1936 in terms of tree species composition and of general stand structure. The four major tree species Scots pine, birch, English oak and Norway spruce, which were dominant until 1936, have gradually been replaced by lime and hornbeam. At the same time, the analysis of structural parameters indicates a strong trend towards a homogenization of the vertical stand structure. Possible causes for these dynamics may be changes in sylviculture, climate change and atmospheric deposition. Based on the altered tree species composition it can be concluded that a simple ≪copying≫ (mimicking) of the processes taking place in natural forests may not guarantee the conservation of the multifunctional character of the respective forests.

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

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.

scholarly journals Stand structure and species composition of merbau in logged-over forest in Papua, Indonesia

2018 ◽  
Vol 19 (1) ◽  
pp. 163-171
Author(s):  
PRIJANTO PAMOENGKAS ◽  
ISKANDAR Z. SIREGAR ◽  
AJI NURALAM DWISUTONO
Keyword(s):  
Species Composition ◽  
Stand Structure ◽  
Selective Logging ◽  
Primary Forest ◽  
Growth Stages ◽  
Timber Species ◽  
Natural Forests ◽  
Selective Cutting ◽  
Average Value ◽  
Reference Plot

Pamoengkas P, Siregar IZ, Dwisutono AN. 2018. Stand structure and species composition of merbau in logged-over forest in Papua, Indonesia. Biodiversitas 19: 163-171. Single selective cutting is the most common form of timber extraction in natural forest in the tropics. Although, vast tracts natural forests are already logged-over, the effect of logging on the structure and species composition has been sparsely documented, especially for merbau (Intsia bijuga). Merbau is an excellent timber species and intensively harvested in Papua. The objective of this study was to analyze the structure and species composition of merbau in the several logged-over forests at different ages, i.e., 1, 5, 11, 16, 21 years old after selective logging and primary forest as the reference plot. The study was conducted in February 2016 at Sarmi District, Papua. The distributions of merbau in each plot varies but when they were compared with that in the primary forest that had reached 9.81%. Thus, the decrease of merbau trees in the plots of logged forest areas was not significant. Index of Diversity of all growth stages was high. In general, the number of merbau seedling regeneration in the study plots are above the average value standardized in Selective Cutting and Replanting System (TPTI) regulation. With regard to the condition of sapling regeneration, we concluded that selective logging might not provide enough growing space for regeneration of merbau. Providing appropriate growing space is one of the key factors to achieve adequate merbau natural regeneration.

Forest Regrowth on the Cumberland Plateau and Implications for Productive Management

1983 ◽  
Vol 7 (4) ◽  
pp. 208-212 ◽  
Author(s):  
Robert N. Muller
Keyword(s):  
Species Composition ◽  
Basal Area ◽  
Stand Density ◽  
Cumberland Plateau ◽  
Old Growth ◽  
Nutrient Pools ◽  
Old Growth Forest ◽  
Composition And Structure ◽  
Second Growth ◽  
Commercial Species

Abstract An old-growth forest and a 35-year-old, second-growth forest on the Cumberland Plateau were studied to compare species composition and structure. Species composition and total basal area of the two stands did not differ, although total stand density was 19 percent lower and basal area of commercial species was 25 percent higher in the old-growth than in the second-growth stand. Analysis of size-class distributions showed that both stands were best represented by an inverse J-shaped distribution, which best describes old-age stands. The rapid regeneration of the second-growth stand seems to be the result of minimal disturbance to accumulated nutrient pools in the soil. The importance of these accumulated nutrient pools and implications for forest management on the Cumberland Plateau are discussed.

scholarly journals Effects of Oak Decline on Species Composition in a Northern Arkansas Forest

2003 ◽  
Vol 27 (4) ◽  
pp. 264-268 ◽  
Author(s):  
Eric Heitzman
Keyword(s):  
Species Composition ◽  
Tree Mortality ◽  
Stand Structure ◽  
Acer Rubrum ◽  
Basal Area ◽  
Red Oak ◽  
Oak Decline ◽  
Northern Red Oak ◽  
Red Maple ◽  
White Oak

Abstract Since 1999, widespread and locally severe oak decline and mortality have occurred throughout the Ozark Mountains of northern Arkansas and southern Missouri. A contributing factor in the decline and mortality is an outbreak of the red oak borer [Enaphalodes rufulus (Haldeman) (Coleoptera: Cerambycidae)]. In northern Arkansas, a 2,150 ac mature oak forest severely affected by decline was selected as a case study to describe changes in species composition and stand structure and to assess regeneration potential of oaks and non-oak species. Mortality reduced total overstory basal area from 105 to 57 ft2/ac, and overstory density decreased from 156 to 89 trees/ac. Most dead and dying trees were northern red oak (Quercus rubra L.) and black oak (Q. velutina Lam.). Basal area and density of overstory red oaks were reduced from 51 to 11 ft2/ac and from 60 to 11 trees/ac, respectively. These trees died regardless of dbh class. Mortality was less common in white oak (Q. alba L.) and was generally limited to smaller trees. Understory trees and taller seedlings were predominantly red maple (Acer rubrum L.), flowering dogwood (Cornus florida L.), blackgum (Nyssa sylvatica Marsh.), and black cherry (Prunus serotina Ehrh.). Oaks less than 3 ft tall were abundant, but taller oak seedlings and saplings were uncommon. Tree mortality increased the proportion of white oak and hickories (Carya spp.) in the overstory, and stimulated a regeneration response of mostly non-oak species. South. J. Appl. For. 27(4):264–268.

Structural stocking guides: a new look at an old friend

2004 ◽  
Vol 34 (5) ◽  
pp. 1044-1056 ◽  
Author(s):  
Jeffrey H Gove
Keyword(s):  
Basal Area ◽  
Primary Objective ◽  
Diameter Distribution ◽  
Minimal Amount ◽  
Forest Types ◽  
Quadratic Mean ◽  
Parameter Recovery ◽  
Distribution Shape ◽  
New Information ◽  
New Type

A parameter recovery-based model is developed that allows the incorporation of diameter distribution information directly into stocking guides. The method is completely general in applicability across different guides and forest types and could be adapted to other systems such as density management diagrams. It relies on a simple measure of diameter distribution shape, the basal area larger than quadratic mean stand diameter, to estimate the parameters of the unknown distribution. This latter quantity is shown to have high correlation with stocking guide variables in northeastern forest types. A primary objective of this new type of guide is that its use should require a minimal amount of new information from the user and that the underlying model should be as simple as possible.

scholarly journals Evaluating Efficiency of Sampling Schemes in Tropical Natural Forests: Review and Simulation Experience from Kenya

2019 ◽  
pp. 1-15
Author(s):  
Joseph Hitimana ◽  
James Legilisho Ole Kiyiapi ◽  
Balozi Kirongo Bekuta
Keyword(s):  
Forest Type ◽  
Sampling Error ◽  
Basal Area ◽  
Sampling Technique ◽  
Montane Forest ◽  
Systematic Sampling ◽  
Natural Forests ◽  
Forest Types ◽  
Sampling Schemes ◽  
Plot Size

Forest measurements, especially in natural forests are cumbersome and complex. 100% enumeration is costly and inefficient. This study sought to find out reliable, efficient and cost-effective sampling schemes for use in tropical rain forest (TRF), moist montane forest (MMF) and dry woodland forest (DWF) in Kenya. Forty-eight sampling schemes (each combining sampling intensity (5, 10, 20, 30%), plot size (25, 50, 100, 400 m2) and sampling technique (simple random sampling, systematic sampling along North-South and along East-West orientations) were generated for testing estimates of forest attributes such as regeneration through simulation using R-software. Sampling error and effort were used to measure efficiency of each sampling scheme in relation to actual values. Though forest sites differed in biophysical characteristics, cost of sampling increased with decreasing plot size regardless of the forest type and attribute. Accuracy of inventory increased with decreasing plot size. Plot sizes that captured inherent variability were 5mx5m for regeneration and trees ha-1 across forest types but varied between forest types for basal area. Different sampling schemes were ranked for relative efficiency through simulation techniques, using regeneration as an example. In many instances systematic sampling-based sampling schemes were most effective. Sub-sampling in one-hectare forest unit gave reliable results in TRF (e.g. SSV-5mx5m-30%) and DWF (e.g. SSV-10mx10m-30%) but not in MMF (5mx5m-100%). One-hectare-complete-inventory method was found inevitable for regeneration assessment in montane forest.

scholarly journals Species Composition and Structure of a Northern Hardwood Stand After 61 Years of Group/Patch Selection

1999 ◽  
Vol 16 (3) ◽  
pp. 151-153 ◽  
Author(s):  
W. B. Leak
Keyword(s):  
Species Composition ◽  
New Hampshire ◽  
Basal Area ◽  
Diameter Distribution ◽  
Patch Selection ◽  
Northern Hardwood ◽  
Composition And Structure ◽  
Species Composition And Structure

Abstract The 61-year results from a study of group/patch selection in New Hampshire (four entries, 0.5 ac average opening size) showed that this system will maintain a continued proportion of about 20% of the basal area in bitches and ash, or about one-third in all intolerant/intermediate species.The diameter distribution closely followed the J-shaped curve typical of unevenaged forests. There was a dead standing component of about 20 trees per acre including 3 sawtimber-sized stems. North. J. Appl. For: 16(3):151-153.

scholarly journals Changes in forest structure over 60 years: tree densities continue to increase in the Pilliga forests, New South Wales, Australia

2012 ◽  
Vol 60 (1) ◽  
pp. 1 ◽  
Author(s):  
Robyn K. Whipp ◽  
Ian D. Lunt ◽  
Peter G. Spooner ◽  
Ross A. Bradstock
Keyword(s):  
Stand Structure ◽  
New South ◽  
New South Wales ◽  
Basal Area ◽  
Forest Types ◽  
Natural Ecosystems ◽  
South Wales ◽  
Eucalyptus Crebra ◽  
Callitris Glaucophylla

Studies of long-term vegetation changes are critical for enhancing our understanding of successional dynamics in natural ecosystems. By comparing forest inventory data from the 1940s against field data from 2005, we document changes in stand structure over 60 years in forests co-dominated by Callitris glaucophylla J.Thompson & L.Johnson, Allocasuarina luehmannii (R.Baker) L.Johnson and Eucalyptus crebra F.Muell., in central Pilliga, New South Wales (NSW), Australia. Sampling was stratified across two forest types and across a 1951 wildfire boundary, to assess the effects of initial stand structure and early disturbance on stand dynamics. Stems in the size range tallied in the 1940s (>8.9 cm DBH for Callitris and >11.4 cm for Allocasuarina and Eucalyptus) of each genus increased about three-fold in density and about four-fold in basal area over 60 years, with similar trends in both forest types and fire zones. On average, there were 3638 stems ha–1 in 2010, of which 86% were small Allocasuarina and Callitris (<11.4-cm and <8.9-cm diameter at breast height, DBH, respectively). These results illustrate a continuation of forest encroachment that was initially documented in the late 1800s. However, increases in Allocasuarina have received little attention compared with Callitris recruitment. In the absence of disturbance, ongoing increases in stand stocking may be expected.

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