EAS Publisher | Advancing Height–Diameter Modeling in Pine Stands: A Comparative Analysis of Mixed-Effects Allometry and Age-Dependent Covariates

Advancing Height–Diameter Modeling in Pine Stands: A Comparative Analysis of Mixed-Effects Allometry and Age-Dependent Covariates

DOI : https://doi.org/10.36349/easjals.2026.v09i05.001

PDF

HTML

XML

8 Downloads 14 Views

Accurate estimation of tree height from diameter at breast height (DBH) is essential for biomass estimation, productivity assessment, and carbon accounting. This study evaluated five modeling frameworks namely: linear, logarithmic, polynomial, fixed allometric, and mixed-effects allometric, using measurements from 432 pine trees collected across managed plantation plots in central Uganda. The dataset covered a wide DBH range (5.2–54.8 cm), ensuring representation across multiple growth stages. Among fixed-effects models, the polynomial structure achieved strong predictive performance (R² = 0.914). However, the age-integrated mixed-effects allometric model produced superior predictive reliability (R² = 0.932; RMSE = 1.48 m) and substantially reduced Akaike Information Criterion (AIC) values. Residual analysis indicated stable variance and absence of systematic error patterns. The integration of stand age therefore, significantly improved prediction accuracy and captured vertical growth differences among developmental stages / ages and subsequently offer practical benefits for forest inventory and carbon estimation programs.

TOP EDITORS

Dr. T. Selvankumar
Chief Editor
EAS Journal of Biotechnology and Genetics

Dr. James Kay, PhD
Chief Editor
EAS Journal of Psychology and Behavioural Sciences

Dr. Rejeesh Menon
Chief Editor
EAS Journal of Medicine and Surgery

Dr. S. Jayachandran
Chief Editor
EAS Journal of Dentistry and Oral Medicine

Dr. Md. Habibur Rahman
Chief Editor
EAS Journal of Pharmacy and Pharmacology

Dr. Benard Chemwei, PhD
Chief Editor
East African Scholars Multidisciplinary Bulletin

NFI Joseph Lon
Chief Editor
EAS Journal of Humanities and Cultural Studies

Prof. Dr. Nazir Ahmad Suhail
Chief Editor
East African Scholar Journal of Engineering and Computer Sciences

Dr. Hamid Osman Hamid
Chief Editor
EAS Journals of Radiology and Imaging Technology

Dr. BOUCENNA Mounir
Chief Editor
EAS Journal of Veterinary Medical Science

OPEN ACCESS JOURNALS

Professor Thomas Count Dracula, MD, PhD

Distinguished Professor of Haematology Head — Experimental, Historical & Sensory Haematology Vlad the Impaler University, Wolf’s Lane, Wooden Stakes Grove 666, Transylvania.

BEST AUTHOR

Of The Month

TRACK YOUR ARTICLE

Enter the Manuscript Reference Number (MRN)

Get Details