scholarly journals Dominant Height Model for Site Classification ofEucalyptus grandisIncorporating Climatic Variables

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
José Roberto Soares Scolforo ◽  
Romualdo Maestri ◽  
Antonio Carlos Ferraz Filho ◽  
José Márcio de Mello ◽  
Antônio Donizette de Oliveira ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Eucalyptus Grandis ◽  
Site Index ◽  
Climatic Variables ◽  
Site Classification ◽  
Monthly Precipitation ◽  
Annual Increment ◽  
Dominant Height ◽  
Mean Annual Increment ◽  
Height Model

This study tested the effects of inserting climatic variables inEucalyptus grandisas covariables of a dominant height model, which for site index classification is usually related to age alone. Dominant height values ranging from 1 to 12 years of age located in the Southeast region of Brazil were used, as well as data from 19 automatic meteorological stations from the area. The Chapman-Richards model was chosen to represent dominant height as a function of age. To include the environmental variables a modifier was included in the asymptote of the model. The asymptote was chosen since this parameter is responsible for the maximum value which the dominant height can reach. Of the four environmental variables most responsible for database variation, the two with the highest correlation to the mean annual increment in dominant height (mean monthly precipitation and temperature) were selected to compose the asymptote modifier. Model validation showed a gain in precision of 33% (reduction of the standard error of estimate) when climatic variables were inserted in the model. Possible applications of the method include the estimation of site capacity in regions lacking any planting history, as well as updating forest inventory data based on past climate regimes.

Classification of Eucalyptus plantation Site Index (SI) and Mean Annual Increment (MAI) prediction using DEM-based geomorphometric and climatic variables in Brazil

2020 ◽  
pp. 1-18
Author(s):  
Aliny Aparecida Dos Reis ◽  
Steven E. Franklin ◽  
Fausto Weimar Acerbi Júnior ◽  
Antonio Carlos Ferraz Filho ◽  
José Marcio de Mello
Keyword(s):  
Site Index ◽  
Climatic Variables ◽  
Annual Increment ◽  
Eucalyptus Plantation ◽  
Mean Annual Increment

scholarly journals Dominant height projection model with the addition of environmental variables

CERNE ◽  
2011 ◽  
Vol 17 (3) ◽  
pp. 427-433 ◽  
Author(s):  
Antonio Carlos Ferraz Filho ◽  
José Roberto Soares Scolforo ◽  
Maria Zélia Ferreira ◽  
Romualdo Maestri ◽  
Adriana Leandra de Assis ◽  
...  
Keyword(s):  
Climatic Variables ◽  
Monthly Precipitation ◽  
Inventory Data ◽  
Conventional Model ◽  
Projection Model ◽  
Richards Model ◽  
Dominant Height ◽  
Southern Bahia ◽  
Climatic History ◽  
Height Model

This study investigated the behavior of climatic variables inserted as inclination modifiers of the Chapman-Richards model for estimating dominant height. Thus, 1507 data pairs from a Continuous Forestry Inventory of clonal eucalyptus stands were used. The stands are located in the States of Espírito Santo and southern Bahia. The climatic variables were inserted in the dominant height model because the model is a key variable in the whole prognosis system. The models were adjusted using 1360 data pairs, where the rest of the data was reserved for model validation. The climatic variables were selected by using the Backward model construction method. The climatic variables indicated by the Backward method and inserted in the model were: mean monthly precipitation and solar radiation. The inclusion of climatic variables in the model resulted in a precision gain of 19.8% for dominant height projection values when compared with the conventional model. The advantage of the method used in this study is the actualization of inventory data contemplating climatic history and productivity estimates in areas without prior plantation.

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.

scholarly journals Results of 20 years old Douglas-fir provenance experiment established on the northern slopes of Rila Mountain in Bulgaria

2014 ◽  
Vol 60 (No. 9) ◽  
pp. 394-399 ◽  
Author(s):  
E.B. Popov
Keyword(s):  
Douglas Fir ◽  
Average Height ◽  
Provenance Trial ◽  
Annual Increment ◽  
Growing Stock ◽  
Breast Height ◽  
Dominant Height ◽  
Seed Zone ◽  
Stock Volume ◽  
Mean Annual Increment

The purpose of this study is to facilitate the detection of provenances relevant to the reforestation practice in Bulgaria. Studies were carried out in a Douglas-fir provenance trial plantation established at an altitude of 800 m a.s.l. on the northern slopes of Rila Mountain. To establish the productivity, assess the stands and rank provenances biometric procedures, methods of descriptive statistics and ANOVA were used. The diameter at breast height, average height, dominant height, total growing stock volume, assortment timber structure and survival of trees were analyzed in the stands of 55 Douglas-fir provenances. The provenances were characterized in terms of productivity of forest stands at 20 years of age and their ability to produce high quality timber was evaluated. Provenances: Newhalem No. 4 (Seed zone 402), Darrington No. 7 (Seed zone 403), Parkdale No. 19 (Seed zone 661) and Idanha No. 29 (Seed zone 452) have been recommended. Among the recommended provenances are those with growing stock volume with branches from 296 to 354 m<sup>3</sup>&middot;ha<sup>&ndash;1</sup>, mean annual increment from 14.8 to 17.7 m<sup>3</sup>&middot;ha<sup>&ndash;1</sup> and dominant heights of up to 17.9 m. &nbsp;

Assessing multiple estimates of plantation productivity

1989 ◽  
Vol 19 (8) ◽  
pp. 948-954 ◽  
Author(s):  
David D. Reed ◽  
Elizabeth A. Jones
Keyword(s):  
Site Index ◽  
Classification Systems ◽  
Pine Plantations ◽  
Annual Increment ◽  
Habitat Classification ◽  
Soil Site ◽  
Plantation Productivity ◽  
Mean Annual Increment ◽  
True Values ◽  
Forest Managers

Forest managers are often faced with several estimates of plantation productivity. Not only are there different measures of productivity, such as site index or mean annual increment at some fixed age, but estimates of each may be obtained from several sources, including habitat classification systems, soil site equations, and growth measures from young stands. Site index cannot be truly observed until the stand reaches index age, and mean annual increment cannot be truly observed without measuring standing volume at the age of interest. Without observations of these "true" values, common measures of accuracy have only generally evaluated performance compared to a standard method that accurately predicts these values. In this paper, a technique of assessing alternative estimates of site index and mean annual increment in the absence of observations of the true values is presented and is illustrated through a quantitative evaluation of the alternative productivity estimates for young red pine plantations.

Adjustment of the age–height relationship for uneven-aged black spruce stands

2008 ◽  
Vol 38 (7) ◽  
pp. 2003-2012 ◽  
Author(s):  
Hakim Ouzennou ◽  
David Pothier ◽  
Frédéric Raulier
Keyword(s):  
Black Spruce ◽  
Information Criterion ◽  
Diversity Indices ◽  
Site Index ◽  
Diameter Distribution ◽  
Large Network ◽  
Permanent Sample Plots ◽  
Dominant Height ◽  
Spruce Stands ◽  
Height Model

Site index (SI) is commonly used in natural stands, even when their diameter distribution deviates from that of the monospecific, even-aged, fully stocked stands used to develop basic age–height relationships. Since deviations from basic age–height trajectories can be reflected in deviations of stand diameter distribution from a bell shape, we incorporated different diameter diversity indices into an age–height equation to help improve height predictions and determine which index is best related to stand dominant height. This procedure was performed using black spruce ( Picea mariana (Mill.) BSP) stands from a large network of permanent sample plots established across the province of Quebec, Canada. The age–height model that minimized the Akaike’s information criterion used the Shannon evenness index (ESh) as an equation modifier accounting for the diameter diversity variable. The model showed that for stands established on relatively poor sites (SI = 9), no substantial differences in dominant height were found between two contrasting ESh values. For SI = 15, however, the larger ESh value increased the dominant height by as much as 1 m at 80 years. These results suggest that introduction of ESh into an age–height model can improve calculation of site index, particularly in regions characterized by the presence of numerous uneven-aged stands.

scholarly journals USO DE MODELOS ESTATÍSTICOS PARA CLASSIFICAÇÃO DE SÍTIOS EM POVOAMENTOS DE Pinus taeda NA REGIÃO DE CAÇADOR – SC

FLORESTA ◽  
2011 ◽  
Vol 41 (1) ◽  
Author(s):  
Saulo Jorge Téo ◽  
Diego Ricardo Bressan ◽  
Reinaldo Hoinacki da Costa
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Statistical Models ◽  
Site Index ◽  
Site Classification ◽  
Santa Catarina ◽  
Dominant Height ◽  
Pinus Taeda L ◽  
Santa Catarina State

Este trabalho teve como objetivo testar diferentes modelos estatísticos para ajuste de curvas de índice de sítio e verificar se as curvas anamórficas geradas foram satisfatórias para classificação de sítios em povoamentos de Pinus taeda L. na região de Caçador, SC. Os dados de altura dominante (hdom) utilizados nesta pesquisa foram obtidos de parcelas permanentes de área fixa e formato retangular, com áreas de 500 e 625 m². As parcelas foram distribuídas de forma aleatória nos povoamentos, a fim de abranger a maior variabilidade possível de produtividade. A seleção do melhor modelo estatístico ajustado foi feita por meio das seguintes estatísticas de ajuste e precisão: coeficiente de determinação ajustado (R²aj), erro padrão da estimativa (Syx), erro padrão da estimativa em porcentagem (Syx%) e distribuição de resíduos em porcentagem. O modelo monomolecular apresentou os melhores resultados para os critérios de seleção, portanto foi escolhido para a construção das curvas de índice de sítio pelo método da curva guia. Depois de se proceder à classificação de sítios, foram realizados testes de anamorfismo, os quais indicaram o padrão anamórfico das curvas geradas pelo modelo estatístico ajustado para classificação de sítios dos povoamentos de Pinus taeda na região de Caçador, SC.Palavras-chave:  Modelos estatísticos; teste de anamorfismo; curvas de índice de sítio; altura dominante. AbstractUse of statistical modells for site classification of Pinus taeda plantation in the region of Caçador, Santa Catarina State, Brazil. This study aimed to test different statistical models for fitting site index curves and check if the anamorphic curves generated were satisfactory to classify the loblolly pine (Pinus taeda L.) plantations in the region of Caçador, Santa Catarina State, Brazil. The data of dominant height (hdom) used in this study were obtained from permanent plots of fixed area and rectangular shape, with areas of 500 and 625 square meters. The plots were distributed randomly in the stands to cover the largest possible variability of productivity. The selection of the best equation was made by the following fitting and precision statistics: adjusted coefficient of determination (R²aj), standard error of estimation (Syx), standard error of estimate in percentage (Syx%) and graphical distribution of the residuals in percentage. The monomolecular model showed the best performance, so it was chosen for the construction of the site index curves by guide curve method. After construction of the site index curves, the stability of the curves was also tested, which indicated the anamorphic pattern of the curves generated by the equation for site classification of loblolly pine plantations in the region of Caçador, Santa Catarina State, Brazil.Keywords:  Statistical models; test of anamorphism; site index curves; dominant height.

Yield Comparison of Three Douglas-Fir Plantations on Former Farmland in Western Washington

1990 ◽  
Vol 5 (4) ◽  
pp. 123-126
Author(s):  
Marshall D. Murray ◽  
Constance A. Harrington
Keyword(s):  
Pseudotsuga Menziesii ◽  
Nutrient Availability ◽  
Site Index ◽  
Douglas Fir ◽  
Annual Increment ◽  
Volume Yield ◽  
Western Washington ◽  
Natural Stands ◽  
Mean Annual Increment ◽  
Enhanced Yield

Abstract Yields of three Douglas-fir (Pseudotsuga menziesii) plantations on former farmland were substantially greater than DFSIM yields for the plantations based on site index estimates from adjacent natural stands. Volume yield per acre of trees 1.6 in. dbh and larger was 40 to 57% greater in the actual plantations than in the simulations. For trees 7.6 in. dbh and larger, volume yield of the actual plantations was 85 to 151% greater than the simulated yields. Mean annual increment of the actual plantations was 56 to 69% greater than the simulated values. In addition, top height was greater in two of the plantations than predicted. Running a second set of simulations with site index estimates based on plantation trees reduced the discrepancy in yields but still resulted in substantial underpredictions. Some possible reasons for enhanced yield of the plantations on former farmland are greater site uniformity, reduced vegetative competition, and increased nutrient availability. West. J. Appl. For. 5(4):00-00, October 1990.

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