Crown Projection Area Models for Neem ( Azadirachta indica Linn) in Majia Fuelwood Reserve, DangeShuni, Sokoto State, Nigeria
Abstract
This research was conducted in order to develop crown projection area models for Neem (Azadirachta indica) in Majia Fuelwood Reserve. Both non-linear and linear regression models were used. Adjusted coefficient of determination (R2adj) and minimum Standard Error of Estimate (SEE) were deemed suitable criteria for choosing the optimum model. Validation of the models was done by separating the data into two datasets: (75%) of the data for calibration of models, and the other dataset (25%) for validation of the models using a paired sample T-test, and R statistical software was used for the analysis. The study also evaluated various models for predicting canopy characteristics, and one particular model stood out in terms of goodness of fit and simplicity. All the candidate model parameters were found to be statistically significant at 5% with the exception of Model 10 (CPA = b0 + b1LnSLC). This indicates that at least one predictor variable (DBH or SLC) is significant in explaining the dependent variable. Few models fitted well with the data, while most of the models could not predict CPA. Equation 10 (CPA = 26.99861 + 0.101247SLC - 5.9087LnSLC) was found to be the most appropriate in predicting the Crown Projection Area (CPA) of Azadirachta indica. The suggested model offers a useful tool for the prediction of canopy attributes, facilitating informed decision-making in future forest management and timber production. The selected model is considered effective for predicting future growth values, which is essential for sustainable timber production and planning.
Keywords
Azadirachta indicaCrown Projection AreaModelsHeightDiameter at Breast
References
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