CRESCIMENTO, MORTALIDADE, INGRESSO E DISTRIBUIÇÃO DIAMÉTRICA EM FLORESTA OMBRÓFILA MISTA

FLORESTA ◽  
2010 ◽  
Vol 40 (4) ◽  
Author(s):  
Afonso Figueiredo Filho ◽  
Andrea Nogueira Dias ◽  
Thiago Floriani Stepka ◽  
Alex Roberto Sawczuk
Keyword(s):  
Mixed Forest ◽  
Basal Area ◽  
Diameter Distribution ◽  
Permanent Plots ◽  
Forest Fragment ◽  
Dynamic Changes ◽  
Forest Dynamic ◽  
Diameter Increment ◽  
Mean Diameter ◽  
The Mean

A dinâmica de uma Floresta Ombrófila Mista existente na Floresta Nacional de Irati foi avaliada e comparada com resultados de outras pesquisas similares no Sul do Brasil. Os dados advêm de parcelas permanentes (25 ha de área) medidas em 2002, 2005 e 2008. Todas as árvores com diâmetros à altura do peito maiores que 10 cm foram consideradas. Os incrementos em diâmetro e área basal por hectare foram determinados, bem como as taxas de mortalidade e ingresso. Os resultados são apresentados para a floresta como um todo e para as 10 espécies de maior ocorrência. Informações do número de espécies, gêneros, famílias e a evolução da distribuição diamétrica são relatadas. A floresta apresentou 567 árvores/ha, distribuídas em 117 espécies, 80 gêneros e 46 famílias. O incremento médio em diâmetro e em área basal foi de 0,24 cm e 0,23 m2/ha/ano. A taxa média anual de mortalidade e de ingresso foi de 1,77 e 1,38%. A área basal foi de 28,7, 29,9 e 30,1 m2/ha em 2002, 2005 e 2008. A floresta e algumas espécies têm uma distribuição diamétrica decrescente, com poucas alterações em sua dinâmica. O trabalho faz ainda uma retrospectiva dos estudos da dinâmica da Floresta Ombrófila Mista no Sul do Brasil.Palavras-chave: Floresta com araucária; incremento; dinâmica florestal; parcelas permanentes. AbstractGrowth, mortality, ingrowth, and diameter distribution in a Mixed Ombrophyllous Forest. The dynamic of a Mixed Ombrophyllous Forest fragment located in the Irati National Forest was evaluated and compared to the results obtained by other similar researches from Southern Brazil. The data came from permanent plots (25 ha) measured in the years 2002, 2005 and 2008. All the trees with DBH larger than 10 cm were considered. The mean diameter increments and the basal area per hectare were determined, as well as the mortality and ingrowth rates. The results were presented for all the species and for the 10 of higher occurrence. The number of species, genus, families, and the diametric distributions were also determined. A total of 567 trees/ha, from 117 species, 80 genus, and 46 families were observed. The annual mean diameter increment and the basal area were 0.24 cm and 0.23 m²/ha, respectively. The annual mean mortality was 1.77% and the ingrowth rate 1.38%. The basal area was 28.7, 29.9 and 30.1 m²/ha in the studied period. The forest and some species presented a decreasing diameter distribution with few dynamic changes. This research also presented a retrospective of other Ombrophyllous Mixed Forest dynamic studies in southern Brazil.Keywords: Araucaria forest; increment; forest dynamic; permanent plots.

scholarly journals Sustainability of High-Value Timber Species in Mixed Conifer–Broadleaf Forest Managed under Selection System in Northern Japan

Forests ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 484
Author(s):  
Kyaw Thu Moe ◽  
Toshiaki Owari
Keyword(s):  
Mixed Forest ◽  
Basal Area ◽  
Basal Area Increment ◽  
Diameter Distribution ◽  
Permanent Plots ◽  
Timber Species ◽  
Selection System ◽  
Management Options ◽  
Species Proportions ◽  
Northern Japan

Understanding the sustainability of high-value timber species in managed forests provides useful information for the management of these species in the long-run. Using nearly 50 years of census data in long-term permanent plots, we investigated the sustainability of three high-value timber species—monarch birch (Betula maximowicziana Regel), castor aralia (Kalopanax septemlobus (Thunb.) Koidz), and Japanese oak (Quercus crispula Blume)—in cool-temperate mixed forest under a selection system in northern Japan. We used stocking, demographic parameters, and species proportions of these species as measures of sustainability. Results showed that the tree density and basal area of the three high-value timber species increased during the study period. Moreover, the basal area increment of these species showed an increasing trend across census periods. However, while no significant differences in the tree mortality of these species were observed, the numbers of in-growth fluctuated across census periods. Increasing trends in species proportions of monarch birch and Japanese oak were observed. Even though there were some fluctuations across census periods, especially in smaller diameter classes, diameter distribution curves of high-value timber species followed a reversed J-shaped pattern. The results revealed that the sustainability measures of high-value timber species can be achieved in forest stands managed under single-tree selection system. In addition, the results also indicated the changing structure and composition of the forest stand. The stocking and basal area increment of conifers decreased while those of broadleaves increased. The proportion of conifers decreased to 33.01% in 2008–2016 from 48.35% in 1968–1978. The results of this study would be useful for adapting silvicultural practices and harvesting practices as well as for simulating various silvicultural and management options for high-value timber species.

Inoptimality losses in forest management decisions caused by errors in an inventory based on airborne laser scanning and aerial photographs

2010 ◽  
Vol 40 (12) ◽  
pp. 2427-2438 ◽  
Author(s):  
Md. Nurul Islam ◽  
Mikko Kurttila ◽  
Lauri Mehtätalo ◽  
Timo Pukkala
Keyword(s):  
Input Data ◽  
Laser Scanning ◽  
Basal Area ◽  
Airborne Laser Scanning ◽  
Aerial Photographs ◽  
Stand Age ◽  
Inventory Data ◽  
Airborne Laser ◽  
Mean Diameter ◽  
The Mean

Errors in inventory data may lead to inoptimal decisions that ultimately result in financial losses for forest owners. We estimated the expected monetary losses resulting from data errors that are similar to errors in laser-based forest inventory. The mean loss was estimated for 67 stands by simulating 100 realizations of inventory data for each stand with errors that mimic those in airborne laser scanning (ALS) based inventory. These realizations were used as input data in stand management optimization, which maximized the present value of all future net incomes (NPV). The inoptimality loss was calculated as the difference between the NPV of the optimal solution and the true NPV of the solution obtained with erroneous input data. The results showed that the mean loss exceeded €300·ha–1 (US$425·ha–1) in 84% of the stands. On average, the losses increased with decreasing stand age and mean diameter. Furthermore, increasing errors in the basal area weighted mean diameter and basal area of spruce were found to significantly increase the loss. It has been discussed that improvements in the accuracy of ALS-based inventory could be financially justified.

scholarly journals Size and Charge Stability of Oil Bodies from Peanut

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Lihua Hao ◽  
Fusheng Chen ◽  
Yimiao Xia ◽  
Lifen Zhang ◽  
Ying Xin
Keyword(s):  
Salt Concentration ◽  
Aqueous Extraction ◽  
Diameter Distribution ◽  
Oil Bodies ◽  
Absolute Value ◽  
Mean Diameter ◽  
Median Diameter ◽  
Charge Stability ◽  
The Mean ◽  
The Absolute

In order to offer scientific bases for the application of oil bodies from peanut in food, this research was undertaken to study the size and charge stability of oil bodies from five peanut varieties. It showed that the mean diameter of oil bodies fromyuhua9719andyuhua9830is obviously larger thanyuhua23,yuhua27, andyuhua9502in the peanut cell. Moreover, the analysis of diameter distribution of oil bodies also showed that the median diameter of oil bodies increased dramatically in the order ofyuhua9719>yuhua9830>yuhua23>yuhua27>yuhua9502after aqueous extraction. The charge stability of oil bodies from peanut was observed with zeta (ζ) potential measurements, which indicated that charge properties and the absolute value of oil bodies from five peanut varieties were significantly affected by pH and salt concentration, but the degree of influence is different. Of the five peanut varieties,yuhua27andyuhua9830possessed excellent charge stability (ζ-potential>35 mV) in neutral microenvironment without salt concentration.

scholarly journals Structural and compositional responses to timber harvesting for an old-growth forest on Changbai Mountain, China – Short Communication

2008 ◽  
Vol 54 (No. 6) ◽  
pp. 281-286 ◽  
Author(s):  
H. Gu ◽  
L. Dai
Keyword(s):  
High Intensity ◽  
Vegetation Type ◽  
Mixed Forest ◽  
Basal Area ◽  
Timber Harvesting ◽  
Diameter Distribution ◽  
Pinus Koraiensis ◽  
Korean Pine ◽  
Important Species ◽  
Old Growth Forest

Broadleaved-Korean pine (<I>Pinus koraiensis</I>) mixed forest is a dominant native vegetation type in the eastern Eurasian Continent. We intended to examine the implications of high-intensity timber harvesting (ca 70% of stand volume) for the sustainable management of a mixed forest ecosystem. We measured trees at three sites: control without cutting, older-cut site cut in 1987 and newer-cut site (cutting in 1997). There were significant differences in structure and composition between these three sites in 2003. There were 4,441 trees of 14 species with basal area 56 m<sup>2</sup> at control plot, 6,314 trees of 16 species with basal area 9 m<sup>2</sup> at newer-cut site and 8,438 trees of 21 species with basal area 31 m<sup>2</sup> at older-cut site (all on the area of 1 ha). The high-intensity timber harvesting system helped promote natural regeneration and the growth of small trees but it also allowed light-demanding tree species to invade into the forest. Dominant position and suitable diameter distribution of economically important species (<I>Pinus koraiensis</I> and <I>Tilia amurensis</I>) were maintained across the three sites. The existing timber harvesting appears to consider short-term economic values to a larger extent than long-term ecological values. To manage the broadleaved-Korean pine mixed forest for both timber production and biodiversity conservation, timber-harvesting intensity must be lowered.

scholarly journals Anthropic disturbances as the main driver of a semideciduous seasonal forest fragment in Minas Gerais

Rodriguésia ◽  
2019 ◽  
Vol 70 ◽  
Author(s):  
Tainá Mamede Cirne Silva ◽  
Warley Augusto Caldas Carvalho ◽  
Marcela de Castro Nunes Santos Terra ◽  
Rubens Manoel dos Santos ◽  
Alisson Borges Miranda Santos ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Basal Area ◽  
Permanent Plots ◽  
Forest Fragment ◽  
Ecological Processes ◽  
Successional Stage ◽  
Tree Community ◽  
Main Driver ◽  
Semideciduous Seasonal Forest ◽  
Protium Spruceanum

Abstract The new environmental conditions imposed by disturbance events often create a mosaic of spots in different successional stages. Our objective was to describe the temporal variation of a semideciduous seasonal forest based on its anthropic disturbance history, verifying possible changes in forest dynamics and structure. We sampled the arboreal vegetation with a diameter at breast height (1.3 m above the ground; DBH) ≥ 5 cm in 15 permanent plots of 20 × 20 m where we performed four inventories (2003, 2005, 2007 and 2015). We observed a density decrease and a basal area increase, which indicates the late successional stage of the analyzed tree community. The phytosociological structure, richness and species diversity of the tree community did not show changes throughout the monitoring. However, the Protium spruceanum predominance may be a response to the environmental changes caused by the mining occurred in the area 250 years ago. The anthropic disturbances enduring influences make this type of work indispensable because it allows the ecological processes understanding, allowing a factual management of the forests by the its effective management and conservation.

scholarly journals Growth performance of Tectona grandis in the western Terai of Nepal

1970 ◽  
Vol 15 (2) ◽  
pp. 6-12 ◽  
Author(s):  
H.B. Thapa ◽  
S.K. Gautam
Keyword(s):  
Rotation Period ◽  
Basal Area ◽  
Tectona Grandis ◽  
Stem Volume ◽  
Wood Production ◽  
Leaf Production ◽  
Diameter Increment ◽  
Standing Trees ◽  
The Mean ◽  
One Year

Assessment of growth, biomass and volume of Tectona grandis (teak) was done at a 13-year old plantation established at Shankarnagar, Rupandehi district. Operations such as prunning, prunning and singling, and thinning were carried out at 4, 7.5 and 8.5 years respectively. Diameter increment was 2.3 cm within one year of thinning. Estimated average fresh wood production was 58.8 kg (87.6 tons ha-1) and 29.6 kg (16.1 tons ha-1) in thinned trees and 75.5 kg (71.4 tons ha-1) for trees after thinning. Likewise green leaf production was 5.1 kg tree-1 (7.5 tons ha-1). Above ground green biomass was 32.6 kg tree-1 (17.7 tons ha-1) for thinned trees, 63.9 kg tree-1 (95.1 tons ha-1) for trees before thinning and 81.9 kg tree-1 (77.2 tons ha-1) for trees after thinning. The mean over bark stem volume was 0.0707 m3. In thinning, 21 m3 per ha-1 volume was removed. The volume of standing trees before thinning at 7.5 years was 105.2 m3 ha-1. After thinning, per unit and mean basal area, biomass and over bark stem volume has increased considerably during 4-years from 7.5 years to 11.5 years. This rotation period could be applied for future plantations and already established teak plantations on good sites in the Terai / Inner Terai of Nepal to supply the wood for veneer and small timbers. Key words: Tectona grandis, growth, biomass, volume, rotation, thinning, Nepal Banko Janakari Vol.15(2) 2005 pp6-12

scholarly journals COMMUNITY STRUCTURE AND REGENERATION STATUS OF TREE SPECIES IN KYONGNOSLA ALPINE SANCTUARY, EASTERN HIMALAYA, INDIA

2021 ◽  
Vol 8 (2) ◽  
pp. 241-257
Author(s):  
Subhajit Lahiri ◽  
Sudhansu Sekhar Dash
Keyword(s):  
Tree Species ◽  
Mixed Forest ◽  
Basal Area ◽  
Habitat Destruction ◽  
Eastern Himalaya ◽  
Diameter Distribution ◽  
Mature Trees ◽  
Regeneration Status ◽  
Adult Trees ◽  
Over Exploitation

Habitat destruction, over exploitation, monoculture are major reasons for loss of primary forests in Himalaya. Tree population, composition and diversity particularly in the temperate Himalaya play a key role in the maintenance of many ecosystem services and natural biogeochemical cycles. The present study explores composition and regeneration status of tree species in a temperate mixed forest in Kyongnosla Alpine Sanctuary, East Sikkim, India.  Two sites at an elevation range of 2800–3800 m were selected and 20 plots of 20 m × 20 m for trees, 80 plots of 5 m × 5 m for saplings, and 160 plots of 1 m × 1 m for seedlings were sampled to study the regeneration status. A total of 17 tree species belonging to 9 genera and 8 families were recorded of which Rhododendron was the most dominant genus with maximum number of species. All the phytosociological attributes, such as relative density, abundance and important value index were calculated. The average species richness of adult trees and saplings was 13.5± 0.7 and for seedlings it was 12.5 ± 0.07. The mean density of seedlings was 3609.77 ± 494.39 individuals/ ha, for saplings  1540 ± 113.13 individuals/ha and of mature trees  548.75 ± 8.83 individuals/ha. Total basal area cover ranged from 36.61 to 40.35 m2/ha for trees, from 1.54 to 1.71 m2/ha for saplings.  Fair regeneration was observed in 64.72% of total species; good regeneration observed in 17.64% species, 11.76 % species exhibited poor regeneration while 5.88% showed no regeneration.  Density-diameter distribution exhibited decrease in tree densities towards higher DBH classes. The study not only provides reliable information on the ecosystem’s health of the sanctuary but also will help in understanding the complexity of the ecosystem function and an approach to conservation of biota.

Eastern cottonwood clonal mixing study: predicted diameter distributions

1994 ◽  
Vol 24 (2) ◽  
pp. 405-414 ◽  
Author(s):  
Steven A. Knowe ◽  
G. Sam Foster ◽  
Randall J. Rousseau ◽  
Warren L. Nance
Keyword(s):  
Weibull Distribution ◽  
Basal Area ◽  
Diameter Distribution ◽  
Minimum Diameter ◽  
Quadratic Mean ◽  
Parameter Recovery ◽  
Eastern Cottonwood ◽  
Mean Diameter ◽  
Quadratic Mean Diameter ◽  
Diameter Distributions

A parameter recovery procedure for the Weibull distribution function was modified to incorporate monocultures and mixtures of eastern cottonwood (Populusdeltoides Bartr.) clones planted in Mississippi and Kentucky. Components of the system included functions to predict stand-level basal area and four percentiles (0th, 25th, 50th, and 95th) of the cumulative diameter distribution. Basal area was predicted as a function of surviving number of trees, dominant height, age, planting location, and the proportion of each clone planted. Clonal proportions, which accounted for 3.6% of the variation in observed basal area, were more important than differences in planting locations, which accounted for 3.0% of the variation. Interactions between clones in mixtures were not significant (p = 0.5676), but some cases of both over- and under-compensation appeared to be developing. Percentiles of the cumulative diameter distribution were predicted as functions of quadratic mean diameter, and therefore included indirect effects of both genetic and planting site differences. Only the minimum diameter (D0) was directly affected by proportions of clones planted. Most of the monocultures and mixtures of clones had smaller minimum diameters than expected for a given value of quadratic mean diameter. The predicted quadratic mean diameter and percentiles were used to recover parameters of the Weibull distribution such that the predicted diameter distribution has the same quadratic mean diameter as obtained from the stand basal area model. The predicted distributions indicated that a common stand-level model was not sufficient for accounting for variations in diameter distributions of eastern cottonwood clones. As a result of the differences in diameter distributions, monocultures and mixtures of the Texas clones appeared to have less volume and greater stand variance than the Mississippi clones.

Properties of the quadratic mean diameter in balanced diameter distributions

1985 ◽  
Vol 15 (2) ◽  
pp. 474-476
Author(s):  
Donald J. Weatherhead ◽  
Roger C. Chapman ◽  
John H. Bassman
Keyword(s):  
Stand Structure ◽  
Basal Area ◽  
Tree Size ◽  
Diameter Distribution ◽  
Quadratic Mean ◽  
Growing Stock ◽  
Mean Diameter ◽  
Quadratic Mean Diameter ◽  
Stand Basal Area ◽  
Diameter Distributions

Balanced diameter distributions are widely used to describe stand structure goals for residual growing stock in uneven-aged forests. The quadratic mean diameter is frequently used as a descriptor of a balanced diameter distribution. In this paper the quadratic mean diameter is shown to be independent of stand basal area for balanced diameter distributions with a common class width, maximum and minimum diameters, and de Liocourt's q ratio. Additionally it is shown that the quadratic mean diameter is relatively insensitive to changes in maximum tree size and q ratios for q ratios 1.5 and larger.

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