scholarly journals Height-Diameter Models for Araucaria angustifolia (Bertol.) Kuntze in Natural Forests

2018 ◽  
Vol 10 (8) ◽  
pp. 133 ◽  
Author(s):  
Emanuel Arnoni Costa ◽  
André Felipe Hess ◽  
Danieli Regina Klein ◽  
César Augusto Guimarães Finger

The height-diameter relationship of Araucaria angustifolia trees in different sociological positions (dominant, codominant, dominated) was evaluated in a native forest in the south of Brazil, aiming to find accuracy in its estimation and its use as a component of forest description, growth and yield. The total number of trees of the three sociological positions was 657. Part of these trees of each sociological position was used to estimate the parameters of models, and the remaining for model evaluation. Thus, the objective of this work was to find the best height estimate using nonlinear models, linear with dummy variable, principal component with nonlinear regression, and principal component with mixed nonlinear regression. The criteria for accuracy of fit were adjusted coefficient of determination, root mean square error and mean error. The results showed that the fit using principal component with mixed nonlinear regression obtained consistent results and better accuracy. It showed that height growth capacity depends on the sociological position.

FLORESTA ◽  
2014 ◽  
Vol 44 (4) ◽  
pp. 725
Author(s):  
Renata Diane Menegatti ◽  
Pedro Higuchi ◽  
Ana Carolina Da Silva ◽  
João Fert-Neto ◽  
Jean Correia ◽  
...  

O presente estudo teve como objetivo caracterizar a relação etnobotânica de proprietários rurais do município de Urupema, SC, com recursos florestais. Para isso, foram realizadas entrevistas, em cada uma das 35 propriedades amostradas, sobre as principais fontes de renda e sobre as principais espécies florestais utilizadas. O uso das espécies foi analisado por meio do Nível de Fidelidade (NF) e da Porcentagem de Concordância quanto aos Usos Principais (CUP). As fontes de renda relatadas com maior frequência foram a pecuária, a fruticultura e a aposentadoria. Os recursos florestais são utilizados, principalmente, para fins de alimentação e energético. Todas as espécies citadas apresentaram elevado NF (≥ 97%) e a Araucaria angustifolia (Bertol.) Kuntze é a espécie de maior valor de CUP (97,06%), por ser utilizada por quase a totalidade dos entrevistados (34), sempre para os mesmos fins. Os resultados demonstraram que a maioria dos entrevistados (83%) não obtém renda das florestas naturais, mesmo com quase metade (47%) tendo citado que seria possível sustentar a família por meio da exploração dos recursos florestais nativos. Dentre os recursos florestais explorados, destacou-se a extração de pinhão como fonte de renda.Palavras-chave: Floresta com Araucária; Planalto Catarinense; etnobotânica; produtores rurais. AbstractEthnobotanical connections of rural landowners in the municipality of Urupema, SC, with forest resources. The present research aimed to characterize the ethnobotanical connections of rural landowners in the municipality of Urupema, SC, with their use of forest resource. In order to do that, we conducted interviews, in each of the 35 surveyed properties, focusing the main source of income as well as the main used tree species. The species usages were analyzed by the Fidelity Level (NF) and Percentage of Main Use Concordance (CUP). The most frequent sources of income were livestock, fruit culture and retirement. The forest resources are mainly used as food and energy. All cited species revealed elevated values of NF (≥97%), and the more elevated value of CUP was observed for Araucaria angustifolia (Bertol.) Kuntze (97,06%), as such species had been reported by almost the totality of farmers, always for the same purpose. The results revealed that most of the interviewees (83%) do not get income from natural forests, even with almost half (47%) of them considering that it would be possible to sustain their family by native forest resources exploitation. Among the exploited forest resources, the extraction of pine nuts stood out as income source.Keywords: Araucaria Forest; Planalto Catarinense; forest resource usages; ethnobotany, farmers.


CERNE ◽  
2016 ◽  
Vol 22 (4) ◽  
pp. 493-500 ◽  
Author(s):  
Emanuel Arnoni Costa ◽  
Thomas Schroder ◽  
César Augusto Guimarães Finger

ABSTRACT Height-diameter relationships are used in order to make forest inventories less expensive and to assess growth and yield. This study aimed to develop height-diameter models for individual trees of Araucaria angustifolia (Bertol.) Kuntze for different locations and growth conditions in Southern Brazil. Our data include locations of at least one third of this species natural geographical distribution. We used Michailoff’s model, and compared height-diameter tendency through analytical methods. The model showed good overall precision and accuracy. Trees growing in forest conditions had a higher asymptotic height, and reached it at smaller diameters than open-grown trees. Different regions had contrasting height-diameter tendency indicating site potential, especially for natural forests. Individual tree asymptotic height was correlated with site altitude and mean annual precipitation. This study represents a source of parameters for height-diameter relationships in a large geographical span, for a species with high cultural and timber value in Southern Brazil.


2020 ◽  
Vol 13 (2) ◽  
pp. 112-121
Author(s):  
Sudiyar . ◽  
Okto Supratman ◽  
Indra Ambalika Syari

The destructive fishing feared will give a negative impact on the survival of this organism. This study aims to analyze the density of bivalves, distribution patterns, and to analyze the relationship of bivalves with environmental parameters in Tanjung Pura village. This research was conducted in March 2019. The systematic random system method was used for collecting data of bivalves. The collecting Data retrieval divided into five research stasions. The results obtained 6 types of bivalves from 3 families and the total is 115 individuals. The highest bivalve density is 4.56 ind / m², and the lowest bivalves are located at station 2,1.56 ind / m²,  The pattern of bivalve distribution in the Coastal of Tanjung Pura Village is grouping. The results of principal component analysis (PCA) showed that Anadara granosa species was positively correlated with TSS r = 0.890, Dosinia contusa, Anomalocardia squamosa, Mererix meretrix, Placamen isabellina, and Tellinella spengleri were positively correlated with currents r = 0.933.


2020 ◽  
Vol 14 (1) ◽  
pp. 45-60
Author(s):  
Yashinta Yashinta ◽  
Dwi Hurriyati

This study aims to determine the relationship of loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city. Research subjects numbered 220 people using random sampling methods. Data was collected using a 60 item problematic internet use scale and a 60 item loneliness. Realibility is generated on scale of problematic internet use of 0,955 and loneliness of 0,946.Hypothesis testing uses product moment correlation analysis techniques. Hypothesis test results showed a positive relationshif between loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city r= 0,684 with a significance level of 0,000 (p<0,01). Loneliness in this study made an effective contribution of 46,8% to problematic internet use which can be seen from the coefficient of determination (r²) that is equel to 0,468.


2018 ◽  
Vol 13 (1) ◽  
pp. 38-48
Author(s):  
Mudofar Mudofar

The purpose of this study is to determine the effect of facilities, motivation, and workdiscipline on the work performance of PT Zebra Asaba Industrui employees. The research methodused is descriptive method with regression and correlation approaches which is a method that aims todescribe the influence and relationship of something that is going on at the time the research isconducted. The results of this study indicate partially or simultaneously facility variables,motivation, and work discipline have a significant effect on employee performance. The magnitude ofthe correlation value (R) is 0.924 which means that there is a strong correlation / relationshipbetween facilities, motivation, and work discipline with employee performance. The amount ofadjusted coefficient of determination (R2) is 0.793 or 79.3%, which means that independentvariables can explain changes in employee performance variables by 79.3% while the remaining20.7% is explained by other factors beyond this research.


Author(s):  
Sunil K. Deokar ◽  
Nachiket A. Gokhale ◽  
Sachin A. Mandavgane

Abstract Biomass ashes like rice husk ash (RHA), bagasse fly ash (BFA), were used for aqueous phase removal of a pesticide, diuron. Response surface methodology (RSM) and artificial neural network (ANN) were successfully applied to estimate and optimize the conditions for the maximum diuron adsorption using biomass ashes. The effect of operational parameters such as initial concentration (10–30 mg/L); contact time (0.93–16.07 h) and adsorbent dosage (20–308 mg) on adsorption were studied using central composite design (CCD) matrix. Same design was also employed to gain a training set for ANN. The maximum diuron removal of 88.95 and 99.78% was obtained at initial concentration of 15 mg/L, time of 12 h, RHA dosage of 250 mg and at initial concentration of 14 mg/L, time of 13 h, BFA dosage of 60 mg respectively. Estimation of coefficient of determination (R 2) and mean errors obtained for ANN and RSM (R 2 RHA = 0.976, R 2 BFA = 0.943) proved ANN (R 2 RHA = 0.997, R 2 BFA = 0.982) fits better. By employing RSM coupled with ANN model, the qualitative and quantitative activity relationship of experimental data was visualized in three dimensional spaces. The current approach will be instrumental in providing quick preliminary estimations in process and product development.


2017 ◽  
Vol 48 (1) ◽  
Author(s):  
Thais Destefani Ribeiro ◽  
Taciana Villela Savian ◽  
Tales Jesus Fernandes ◽  
Joel Augusto Muniz

ABSTRACT: The goal of this study was to elucidate the growth and development of the Asian pear fruit, on the grounds of length, diameter and fresh weight determined over time, using the non-linear Gompertz and Logistic models. The specifications of the models were assessed utilizing the R statistical software, via the least squares method and iterative Gauss-Newton process (DRAPER & SMITH, 2014). The residual standard deviation, adjusted coefficient of determination and the Akaike information criterion were used to compare the models. The residual correlations, observed in the data for length and diameter, were modeled using the second-order regression process to render the residuals independent. The logistic model was highly suitable in demonstrating the data, revealing the Asian pear fruit growth to be sigmoid in shape, showing remarkable development for three variables. It showed an average of up to 125 days for length and diameter and 140 days for fresh fruit weight, with values of 72mm length, 80mm diameter and 224g heavy fat.


CERNE ◽  
2010 ◽  
Vol 16 (3) ◽  
pp. 347-357 ◽  
Author(s):  
Afonso Figueiredo Filho ◽  
Andrea Nogueira Dias ◽  
Sintia Valerio Kohler ◽  
Aline Angélica Verussa ◽  
Ademar Luiz Chiquetto

The aim of this study was to assess and model the evolution of the hypsometric relationship in Araucaria angustifolia plantations grown in the 1940's and 1960's in the Irati National Forest, in the mid-south region of Paraná state, Brazil. Using the complete stem analysis method, it was possible to reconstitute the past annual growth of the diameter at 1.3 m (d) and of the total height (h) of a sample of 30 trees, selected so as to cover diametric and age variability. Eleven discs were removed from each tree at 0.1 and 1.3 m and at 15, 25, 35,..., 95% of the total height. Eleven models traditionally used in hypsometric relationships were tested, two of which were considered generic because they involved the age variable. The models were selected based on the Adjusted Coefficient of Determination (R²Adj), Standard Estimate Error (Syx), absolute (m) and relative (%), and on the graphic distribution of residues in percentage. In the models tested by age, no tendencies were observed and erros (Syx) remained below 14.6%, except for ages 5 and 11. However, the coefficients of determination were low, ranging from 0.29 to 0.55. The Curtis generic model (1970), selected to represent the h/d curve for all ages, also presented a satisfactory performance (R²Adj = 0.87 and Syx = 16%), with results similar to those obtained for the models in each age. As age increases, the h/d curve shifts to the right and changes level, remaining steep at the younger ages and more stable and flat as the population nears the end of its cycle.


2021 ◽  
Author(s):  
Attah Fakeye ◽  
Olusegun Ige ◽  
Olufemi Ogunsanwo

California Bearing Ratio (CBR) is an important parameter used in designing pavement layers in road construction but testing this parameter requires time, labor, and huge cost. The study therefore applies multivariate approach to evaluate CBR based on contrasted geotechnical parameters along Ilorin-Lokoja highway. The results obtained showed that the migmatite-gneiss-derived soils are slightly more fines (< 0.075 mm; 7.4–59.6%), more plastic (PI; 1.6–39%), and have low strength (MDD = 1.8 mg/m3; CBR = 29.0%) than the metasediments (11–57.7%, 2.0–30%, 1.6 mg/m3, 23.6%) and older granite soils (8.2–32.7%, 2.6–13.4%, 1.7 mg/m3, 27.8%), respectively. The principal component analysis (PCA) revealed three major components (eigenvalues >1) which accounted for 83.8% of the total variance at the rate of 33.4, 14.7, and 11.4%. Major contributing variables for the components were fines (R = 0.87), plasticity index (R = 0.7), and coarse sand (R = 0.67%). Spatial distribution of these groups established interplay of sediment-gradation and moisture-connection evident in hierarchical cluster analysis that revealed patterns of homogeneity and soil relationships. Regression analysis established five models from predictor variables such as fines, activity, free swell, liquid and plastic limits, weighted plasticity index, optimum moisture content, and maximum dry density with the coefficient of determination (R2 = 0.33) and root mean square error (RMSE) of 7.80.


2021 ◽  
Author(s):  
Gastón Mauro Díaz

1) Hemispherical photography (HP) is a long-standing tool for forest canopy characterization. Currently, there are low-cost fisheye lenses to convert smartphones into high-portable HP equipment; however, they cannot be used whenever since HP is sensitive to illumination conditions. To obtain sound results outside diffuse light conditions, a deep-learning-based system needs to be developed. A ready-to-use alternative is the multiscale color-based binarization algorithm, but it can provide moderate-quality results only for open forests. To overcome this limitation, I propose coupling it with the model-based local thresholding algorithm. I call this coupling the MBCB approach. 2) Methods presented here are part of the R package CAnopy IMage ANalysis (caiman), which I am developing. The accuracy assessment of the new MBCB approach was done with data from a pine plantation and a broadleaf native forest. 3) The coefficient of determination (R^2) was greater than 0.7, and the root mean square error (RMSE) lower than 20 %, both for plant area index calculation. 4) Results suggest that the new MBCB approach allows the calculation of unbiased canopy metrics from smartphone-based HP acquired in sunlight conditions, even for closed canopies. This facilitates large-scale and opportunistic sampling with hemispherical photography.


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