National Academy of Agricultural Sciences (NAAS)
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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
The study investigates linear and non-linear regression models for estimating the volume of Tectona Grandis in the Thithimathi forest, Kodagu district, India. With increasing demand for teak plantations under national afforestation programs, accurate volume estimation is essential for productivity and sustainable forest management. Data were collected from three sample plots, each with 30 trees, measuring diameter at breast height (Dbh) and height to calculate tree volume. Karl Pearson’s correlation analysis revealed a strong positive correlation between volume and Dbh, while the relationship between volume and height was weak across plots. Regression models- linear, quadratic and logarithmic were fitted to the data and evaluated using R2 and RMSE values. Results showed that quadratic models consistently provided the best fit, with R2 value 0.9999 and minimal error, outperforming linear and logarithmic models. Multiple linear regression yields high predictive accuracy (R2 = 0.9821). The findings confirm that quadratic regression models are most suitable for teak volume estimation in the Thithimathi forest, offering reliable tools for forest productivity and management.
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