GROWTH AND YIELD OF EVEN-AGED Cupressus lusitanica  PLANTATIONS IN SOUTHERN BRAZIL

Plantation forestry in southern Brazil demands additional timber species to a higher market differentiation by providing high quality timber and exploitation of market niches. Cupressus lusitanica has long been recognized for this purpose but, until now, it was not properly region-wide quantified in terms of growth and yield. The present study delivers the lacking quantitative approach, which may encourage the commercial use of the species. With this study it was aimed at collecting and processing quantitative data from all known C. lusitanica stands in southern Brazil. Inventories were carried out (60 ha, 6-39 years of age) in order to model the development of dominant height (h100), basal area, volume and dominant diameter (d100). Dominant height was the basis for site quality evaluation, delivering site index curves, which, together with the commercial volume of the stands, allowed yield modelling. A wide amplitude of dominant height growth was detected (10-30 m at 20 years), indicating a great site quality variation. At age of 20 years, commercial volumes of 110 and 620 m³ ha-1 were observed for site indexes of 14 and 26, respectively, equivalent to a maximum of 6-31 m³ ha-1 year-1 at ages between 16-18 years. Results demonstrated in a robust manner that C. lusitanica has a high potential for cultivation in southern Brazil. Thus, offering the opportunity of market differentiation by promoting market niches whose demands timber for special solid end-uses.

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SITE QUALITY CURVES FOR AFRICAN MAHOGANY PLANTATIONS IN BRAZIL

CERNE ◽

10.1590/01047760201622042185 ◽

2016 ◽

Vol 22 (4) ◽

pp. 439-448 ◽

Cited By ~ 7

Author(s):

Andressa Ribeiro ◽

Antonio Carlos Ferraz Filho ◽

Margarida Tomé ◽

José Roberto Soares Scolforo

Keyword(s):

Site Index ◽

Growth And Yield ◽

Site Quality ◽

Site Classification ◽

Site Class ◽

African Mahogany ◽

Dominant Height ◽

Curve Method ◽

Dominant Height Growth ◽

The Stability

ABSTRACT Site quality estimation is an important tool in forest management since it is useful for modeling growth and yield for even-aged stands. Data from African mahogany (Khaya ivorensis A. Chev.) Brazilian plantations were used to develop a model to predict dominant height growth, comparing dynamic base-age invariant site index models with the guide curve method (static models). For the evaluation of the candidate models qualitative and quantitative criteria were used. We also verified the stability of the candidate models, preferring a model providing fewer site class changes when predicting site index from different ages. The Lundqvist-Korf function fitted with the guide curve method proved to be effective and accurate for site classification and dominant height predictions of African mahogany stands. The range of observed site index, at a reference age of 15, was between 17 and 33 meters.

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MODELAGEM DO CRESCIMENTO E PRODUÇÃO EM CLASSES DE PRECIPITAÇÃO PLUVIOMÉTRICA PARA Eucalyptus sp.

FLORESTA ◽

10.5380/rf.v45i1.33664 ◽

2014 ◽

Vol 45 (1) ◽

pp. 117 ◽

Cited By ~ 1

Author(s):

Rodrigo Otávio Veiga Miranda ◽

Andrea Nogueira Dias ◽

Afonso Figueiredo Filho ◽

Izabele Domingues Soares ◽

Jovane Pereira Cruz

Keyword(s):

Eucalyptus Grandis ◽

Basal Area ◽

Site Index ◽

Growth And Yield ◽

Eucalyptus Urophylla ◽

Volumetric Growth ◽

Dominant Height ◽

Dominant Height Growth ◽

Key Steps ◽

A Site

Uma das etapas fundamentais na modelagem do crescimento e produção é a identificação dos sítios, geralmente determinados pela relação entre altura dominante e idade. Porém há situações em que se torna interessante o uso de outras variáveis, como a precipitação pluviométrica, devido à grande correlação com a produtividade do povoamento. O objetivo deste estudo foi verificar a influência da estratificação por classes de precipitação pluviométrica no crescimento e produção volumétrica de Eucalyptus sp. Os dados provêm de plantios de híbridos de Eucalyptus grandis W. Hill ex Maiden x Eucalyptus urophylla S. T. Blake, do estado da Bahia, distribuídos em sete classes de precipitação, consideradas como estratos conforme o teste de Dette e Neumeyer (2001). Foram determinados os índices de sítio a cada classe de precipitação, sendo utilizada a área basal inicial média em cada um desses sítios. O modelo de Clutter foi empregado para a modelagem e as estimativas de produção foram comparadas pelo teste F de Graybill. A precipitação média influenciou no crescimento em altura dominante. A modelagem realizada por classe de precipitação gerou resultados similares àqueles obtidos pela modelagem sem estratificação, porém com maior precisão, sendo considerada adequada para estimar a produção para povoamentos clonais de eucalipto.Palavras-chave: Eucalipto; ANCOVA não paramétrica; modelo de Clutter. AbstractModeling of growth and yield by pluviometric precipitation classes for Eucalyptus sp. One of the key steps in modeling of growth and yield is the identification of different sites, which are generally determined by the relation of dominant height and age. However, there are situations in which it becomes interesting to use other variables, such as pluviometric precipitation, due to the high correlation with the productivity of the stand. This research aims to investigate influence of stratification by classes of precipitation in volumetric growth and yield of Eucalyptus sp. We collected data in hybrid stands of Eucalyptus grandis W. Hill ex Maiden x Eucalyptus urophylla S. T. Blake, from the state of Bahia, Brazil; such stands were distributed in seven classes of precipitation, each considered a site accordingly to Dette and Neumeyer (2001) test. We determined the site index for each class of precipitation, using the initial average basal area in each site. The Clutter model was used for modeling, and production estimates compared by Graybill F test. The average precipitation influenced the dominant height growth. The modeling performed by precipitation classes generated similar results to those obtained by modeling without stratification, but more accurately; we can consider it appropriate to estimate production to clonal eucalyptus stands.Keywords: Eucalypt; nonparametric ANCOVA; Clutter model.

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A Dynamic Stand Growth Model System for Loblolly Pine Responding to Mid-Rotation Treatments

Forests ◽

10.3390/f12050556 ◽

2021 ◽

Vol 12 (5) ◽

pp. 556

Author(s):

Mauricio Zapata-Cuartas ◽

Bronson P. Bullock ◽

Cristian R. Montes ◽

Michael B. Kane

Keyword(s):

Growth Model ◽

Loblolly Pine ◽

Basal Area ◽

Model System ◽

Growth And Yield ◽

Site Quality ◽

Response To Treatment ◽

Plantation Management ◽

Vegetation Control ◽

Dominant Height

Intensive loblolly pine (Pinus taeda L.) plantation management in the southeastern United States includes mid-rotation silvicultural practices (MRSP) like thinning, fertilization, competitive vegetation control, and their combinations. Consistent and well-designed long-term studies considering interactions of MRSP are required to produce accurate projections and evaluate management decisions. Here we use longitudinal data from the regional Mid-Rotation Treatment study established by the Plantation Management Research Cooperative (PMRC) at the University of Georgia across the southeast U.S. to fit and validate a new dynamic model system rooted in theoretical and biological principles. A Weibull pdf was used as a modifier function coupled with the basal area growth model. The growth model system and error projection functions were estimated simultaneously. The new formulation results in a compatible and consistent growth and yield system and provides temporal responses to treatment. The results indicated that the model projections reproduce the observed behavior of stand characteristics. The model has high predictive accuracy (the cross-validation variance explained was 96.2%, 99.7%, and 98.6%; and the prediction root mean square distance was 0.704 m, 19.1 trees ha−1, and 1.03 m2ha−1 for dominant height (DH), trees per hectare (N), and basal area (BA), respectively), and can be used to project the current stand attributes following combinations of MRSP and with different thinning intensities. Simulations across southern physiographic regions allow us to conclude that the most overall ranking of MRSP after thinning is fertilization + competitive vegetation control (Fert + CVC) > fertilization only (Fert) > competitive vegetation control only (CVC), and Fert + CVC show less than additive effect. Because of the model structure, the response to treatment changes with location, age of application, and dominant height growth as indicators of site quality. Therefore, the proposed model adequately represents regional growth conditions.

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Modeling Dominant Height Growth of Cedar (Cedrus libani A. Rich) Stands in Turkey

Forest Science ◽

10.1093/forsci/fxz038 ◽

2019 ◽

Vol 65 (6) ◽

pp. 725-733 ◽

Cited By ~ 1

Author(s):

Ramazan Özçelik ◽

Quang V Cao ◽

Esteban Gómez-García ◽

Felipe Crecente-Campo ◽

Ünal Eler

Keyword(s):

Sustainable Forest Management ◽

Model Development ◽

Autoregressive Process ◽

Site Index ◽

Height Growth ◽

Growth And Yield ◽

Site Classification ◽

Cedrus Libani ◽

Dominant Height ◽

Dominant Height Growth

Abstract Sustainable forest management requires accurate prediction from a growth and yield system. Such a system relies heavily on some measure of site productivity, which is often the site index. A model was developed for predicting dominant height growth and site index of even-aged cedar (Cedrus libani A. Rich.) stands in Turkey. Stem-analysis data from 148 trees were used for model development and validation. Six dynamic height–age equations were derived using the generalized algebraic difference approach (GADA). Autocorrelation was modeled by expanding the error term as an autoregressive process. Based on numerical and graphical analysis, a GADA formulation derived from the Chapman–Richards model was selected. Based on relative error in dominant height prediction, 80 years was selected as the best reference age. The resulting equation provided the best compromise between biological and statistical aspects and, therefore, is recommended for height growth prediction and site classification of cedar stands in Turkey.

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The growth and yield responses of a high site quality red pine plantation to seven thinning treatments and two thinning intervals

Canadian Journal of Forest Research ◽

10.1139/x86-091 ◽

1986 ◽

Vol 16 (3) ◽

pp. 513-520 ◽

Cited By ~ 5

Author(s):

Hal O. Liechty ◽

Glenn D. Mroz ◽

David D. Reed

Keyword(s):

Volume Growth ◽

Basal Area ◽

Site Index ◽

Red Pine ◽

Growth And Yield ◽

Site Quality ◽

Pine Plantation ◽

High Site ◽

Yield Responses ◽

Lower Site

Seven thinning treatments with residual densities between 60 and 160 ft3/acre (13.8 and 36.8 m2/ha) of basal area were applied to a highly productive (site index, 81 ft (24.7 m); base age, 50 years) red pine (Pinusresinosa Ait.) plantation. After 10 years, periodic basal area growth was maximized over a lower and much broader range of residual densities than previously found in lower site quality stands. Total and merchantable cubic foot volume growth for the 10 year period was not significantly different between treatments. Application of these thinning treatments on a 6- compared with a 10-year interval reduced total and merchantable cubic foot volume growth while increasing the average stand diameter.

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La qualité des stations et la productivité des plantations de pin rouge (Pinus resinosa Ait.) au Québec.

The Forestry Chronicle ◽

10.5558/tfc51016-1 ◽

1975 ◽

Vol 51 (1) ◽

pp. 16-20

Author(s):

S. Popovich

Keyword(s):

Basal Area ◽

Pinus Resinosa ◽

Site Index ◽

Red Pine ◽

Growth And Yield ◽

Site Quality ◽

Average Height ◽

Stand Volume ◽

Factors Affecting ◽

The Relationship

This paper presents an evaluation of site quality based on the relationship between volume per square foot of basal area and age of plantation, for planted red pine (Pinus resinosa Ait.) in Quebec.A graph for the three site index classes is included with indication for its use. There is a table showing the values of volume per square foot of basal area as a function of average height and average form quotient of a stand, permitting a rapid evaluation of stand volume of a plantation. Finally, several factors affecting growth and yield of red pine plantations for various sites in Quebec are discussed.

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Building a dynamic growth model for trembling aspen in western Canada without age data

Canadian Journal of Forest Research ◽

10.1139/cjfr-2012-0366 ◽

2013 ◽

Vol 43 (3) ◽

pp. 256-265 ◽

Cited By ~ 13

Author(s):

Oscar García

Keyword(s):

Populus Tremuloides ◽

Site Occupancy ◽

Basal Area ◽

Site Index ◽

Growth And Yield ◽

Site Quality ◽

Diameter Distribution ◽

Stand Age ◽

Parameter Estimates ◽

Trembling Aspen

A biologically inspired whole-stand growth and yield model was developed for even-aged thinned or unthinned stands dominated by trembling aspen (Populus tremuloides Michx.). The estimation used permanent sample plot data from British Columbia, Alberta, Saskatchewan, and Manitoba, supplemented by published site index and young stand information. An ingrowth imputation procedure was devised to facilitate the use of plot measurements where small trees are not measured. Two published site index models were closely approximated by a simple age-base invariant equation. Good parameter estimates for mortality and basal area growth were obtained without using age observations, which were unreliable or missing. Four differential equations describe the dynamics of top height, trees per hectare, basal area, and a site occupancy factor. Current values of these variables are used to estimate total and merchantable volumes up to any diameter limit and diameter distribution parameters. When an independent source of site quality estimates is available, the final model does not require stand age knowledge for making growth and yield predictions.

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Allometric Models for Estimating Site Index of Teak (Tectona grandis Linn F.) in Kanya Forest Plantation, Kebbi State, Nigeria

Asian Journal of Environment & Ecology ◽

10.9734/ajee/2019/v10i130110 ◽

2019 ◽

pp. 1-7

Author(s):

A. Dantani ◽

S. B. Shamaki ◽

M. A. Gupa ◽

M. Sa’idu ◽

R. B. Mukhtar ◽

...

Keyword(s):

Basal Area ◽

Tectona Grandis ◽

Site Index ◽

Growth And Yield ◽

Site Quality ◽

Forest Plantation ◽

Age Classes ◽

Total Height ◽

Yield Values ◽

Predicted Height

This study aims to develop site index for Teak (Tectona grandis) in Kanya Forest Plantation, Nigeria. Site index is defined as the total height of the dominant or co-dominant trees at an arbitrary index age, it is a method used for quantifying site quality for pure even-aged stands which is essential in growth and yield modelling. The data used in this study were obtained from six different age classes. Five sample plots each were selected across all age classes in which a total of 712 trees were measured, variables measured include total height, diameter at the base, middle, top, and diameter at the breast height were taken from 30 temporary sampled plots of 25x25m approximately from the centre, 180 dominant trees were selected from 712 trees. Basal area and volume of sampled trees were computed. Yield values obtained from the dominant trees are (B = 249.312 m3/ha, D = 196.128 m3/ha, F = 134.976 m3/ha, C = 119.328 m3/ha, E = 100.320 m3/ ha and A = 86.976 m3/ha). The results showed that B was the best and A was the poorest. Seventeen models were generated and paired sampled t-test was used for model validation, comparing the actual and predicted height. Two out of 17 were rejected (significant P<0.05). The first model Hd=12075.346-354.809(Age)+3.448(Age)2-135193.126(1/Age) is the recommended height estimation of Teak in Kanya Forest plantation for its best performance.

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Modeling Growth and Yield ofSchizolobium amazonicumunder Different Spacings

International Journal of Forestry Research ◽

10.1155/2013/675137 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10

Author(s):

Gilson Fernandes da Silva ◽

Salvador Alejandro Gezan ◽

Carlos Pedro Boechat Soares ◽

Luciano Zumerle Zaneti

Keyword(s):

Basal Area ◽

Site Index ◽

Growth And Yield ◽

Average Height ◽

Study Region ◽

Significant Bias ◽

Dominant Height ◽

Available Information ◽

Area And Volume ◽

Modeling Growth

This study aimed to present an approach to model the growth and yield of the speciesSchizolobium amazonicum(Paricá) based on a study of different spacings located in Pará, Brazil. Whole-stand models were employed, and two modeling strategies (Strategies A and B) were tested. Moreover, the following three scenarios were evaluated to assess the accuracy of the model in estimating total and commercial volumes at five years of age: complete absence of data (S1); available information about the variables basal area, site index, dominant height, and number of trees at two years of age (S2); and this information available at five years of age (S3). The results indicated that the 3 × 2 spacing has a higher mortality rate than normal, and, in general, greater spacing corresponds to larger diameter and average height and smaller basal area and volume per hectare. In estimating the total and commercial volumes for the three scenarios tested, Strategy B seems to be the most appropriate method to estimate the growth and yield of Paricá plantations in the study region, particularly because Strategy A showed a significant bias in its estimates.

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FlorNExT®, a cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait.) stands in Northeastern Portugal

Forest Systems ◽

10.5424/fs/2016252-08975 ◽

2016 ◽

Vol 25 (2) ◽

pp. eRC08 ◽

Cited By ~ 3

Author(s):

Fernando Pérez-Rodríguez ◽

Luis Nunes ◽

Ângelo Sil ◽

João Azevedo

Keyword(s):

Cloud Computing ◽

Pinus Pinaster ◽

Basal Area ◽

Site Index ◽

Maritime Pine ◽

Growth And Yield ◽

Forest Modelling ◽

Transition Functions ◽

Dominant Height ◽

Pinus Pinaster Ait

Aim of the study: To introduce and describe FlorNExT®, a free cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait.) even-aged stands in the Northeast of Portugal (NE Portugal).Area of study: NE Portugal.Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves) and basal area, as well as output functions for tree and stand volume, biomass, and carbon content.Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/.Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal.Keywords: forest management; maritime pine; forest modelling; knowledge transfer tool.

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