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

FLORESTA ◽  
2014 ◽  
Vol 45 (1) ◽  
pp. 117 ◽  
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.

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

FLORESTA ◽  
2021 ◽  
Vol 51 (4) ◽  
pp. 980
Author(s):  
Mário Dobner Jr.
Keyword(s):  
Basal Area ◽  
Site Index ◽  
Growth And Yield ◽  
Site Quality ◽  
Timber Species ◽  
Southern Brazil ◽  
Cupressus Lusitanica ◽  
Dominant Height ◽  
Dominant Height Growth ◽  
Quality Variation

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.

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

2019 ◽  
Vol 65 (6) ◽  
pp. 725-733 ◽  
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.

scholarly journals SITE QUALITY CURVES FOR AFRICAN MAHOGANY PLANTATIONS IN BRAZIL

CERNE ◽  
2016 ◽  
Vol 22 (4) ◽  
pp. 439-448 ◽  
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.

scholarly journals Use data from permanent sampling points in growth and yield modeling

2007 ◽  
Vol 31 (1) ◽  
pp. 59-69 ◽  
Author(s):  
Alexandre José Pereira ◽  
Helio Garcia Leite ◽  
João Carlos Chagas Campos ◽  
Agostinho Lopes de Souza
Keyword(s):  
Eucalyptus Grandis ◽  
Basal Area ◽  
Site Index ◽  
Minas Gerais ◽  
Growth And Yield ◽  
Western Region ◽  
Independent Variables ◽  
Yield Modeling ◽  
Sampling Points ◽  
Growth And Yield Modeling

This study was carried to evaluate the efficiency of the Bitterlich method in growth and yield modeling of the even-aged Eucalyptus stands. 25 plots were setup in Eucalyptus grandis cropped under a high bole system in the Central Western Region of Minas Gerais, Brazil. The sampling points were setup in the center of each plot. The data of four annual mesurements were colleted and used to adjust the three model types using the age, the site index and the basal area as independent variables. The growths models were fitted for volume and mass of trees. The efficiency of the Bitterlich method was confirmed for generating the data for growth and yield modeling.

scholarly journals Modeling Growth and Yield ofSchizolobium amazonicumunder Different Spacings

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.

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

2016 ◽  
Vol 25 (2) ◽  
pp. eRC08 ◽  
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.

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

Forests ◽  
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.

A Growth and Yield Model for Improved Eastern Cottonwood Plantations in the Lower Mississippi Delta

1991 ◽  
Vol 15 (4) ◽  
pp. 213-216 ◽  
Author(s):  
Quang V. Cao ◽  
Kenneth M. Durand
Keyword(s):  
Populus Deltoides ◽  
Mississippi Delta ◽  
Basal Area ◽  
Site Index ◽  
Growth And Yield ◽  
Annual Increment ◽  
Yield Model ◽  
Eastern Cottonwood ◽  
Volume Yield ◽  
Growth And Yield Model

Abstract A compatible growth and yield model was developed based on remeasurement data collected from 183 plots on unthinned improved eastern cottonwood (Populus deltoides Bartr.) plantations in the lower Mississippi Delta. The Sullivan and Clutter (1972) equation form was selected for predicting cubic-foot volume yield and projecting volume from site index and initial age and basal area. Yield equations explained 97% and 94%, respectively, of the variations in total outside bark and merchantable inside bark volumes. Mean annual increment of merchantable volume culminated between 8 and 15 years, depending on site index and initial basal area. South. J. Appl. For. 15(4):213-216.

scholarly journals DENSITY MANAGEMENT DIAGRAM FOR Eucalyptus grandis W. Hill. ex Maiden STANDS CONTROLLED BY DOMINANT HEIGHT

FLORESTA ◽  
2020 ◽  
Vol 51 (1) ◽  
pp. 240
Author(s):  
Gabriel Paes Marangon ◽  
Emanuel Arnoni Costa ◽  
César Augusto Guimarães Finger ◽  
Paulo Renato Schneider ◽  
Matheus Teixeira Martins
Keyword(s):  
Eucalyptus Grandis ◽  
Strong Relationship ◽  
Site Index ◽  
Graphical Analysis ◽  
Coefficient Of Determination ◽  
Permanent Plots ◽  
Volume Number ◽  
Dominant Height ◽  
Development Site ◽  
Relationship Of

Density management diagram for eucalyptus stands controlled by dominant height. The present study aimed to elaborate Density Management Diagrams (DMD) for Eucalyptus grandis W. Hill. ex Maiden stands including the dominant height. Data were obtained from permanent plots installed in the Centro Oriental Riograndense region and the Porto Alegre Metropolitan area, both located in the state of Rio Grande do Sul. The models to describe the relationships between average volume, number of trees per hectare, mean diameter, and dominant height were assessed by the statistical criteria of coefficient of determination (R²), standard error of the estimate in percentage (Syx%), and graphical analysis of residuals. The developed DMD allows for a better control of stocks in the management of stands due to the strong relationship of dominant height with stand development site and forest yield.Keywords: Growth, Site index, Forest regulation, Yield.

Stand growth responses after fertilization for thinned lodgepole pine, Douglas-fir, and spruce in forests of interior British Columbia, Canada

2019 ◽  
Vol 49 (11) ◽  
pp. 1471-1482
Author(s):  
Woongsoon Jang ◽  
Bianca N.I. Eskelson ◽  
Louise de Montigny ◽  
Catherine A. Bealle Statland ◽  
Derek F. Sattler ◽  
...  
Keyword(s):  
British Columbia ◽  
Picea Glauca ◽  
Lodgepole Pine ◽  
Basal Area ◽  
Stand Density ◽  
Site Index ◽  
Douglas Fir ◽  
Picea Sitchensis ◽  
Growth And Yield ◽  
Growth Responses

This study was conducted to quantify growth responses of three major commercial conifer species (lodgepole pine (Pinus contorta Douglas ex Loudon var. latifolia Engelm. ex S. Watson), interior Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. glauca (Beissn.) Franco), and spruce (white spruce (Picea glauca (Moench) Voss) and hybrid spruce (Picea engelmannii Parry ex. Engelm. × Picea glauca (Moench) Voss × Picea sitchensis (Bong.) Carrière))) to various fertilizer blends in interior British Columbia, Canada. Over 25 years, growth-response data were repeatedly collected across 46 installations. The fertilizer blends were classified into three groups: nitrogen only; nitrogen and sulfur combined; and nitrogen, sulfur, and boron combined. The growth responses for stand volume, basal area, and top height were calculated through absolute and relative growth rate ratios relative to a controlled group. Fertilizer blend, inverse years since fertilization, site index, stand density at fertilization, and their interactions with the fertilizer blend were used as explanatory variables. The magnitude and significance of volume and basal area growth responses to fertilization differed by species, fertilizer-blend groups, and stand-condition variables (i.e., site index and stand density). In contrast, the response in top height growth did not differ among fertilization blends, with the exception of the nitrogen and sulfur fertilizer subgroup for lodgepole pine. The models developed in this study will be incorporated into the current growth and yield fertilization module (i.e., Table Interpolation Program for Stand Yields (TIPSY)), thereby supporting guidance of fertilization applications in interior forests in British Columbia.

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