Tree biophysical parameter retrieval using close range photographs Upgupta Sujata1,*, Tiwari Poonam S2, Singh Sarnam3 1Wildlife Institute of India, Dehradun, Uttarakhand 2Indian Institute of Remote Sensing, Dehradun, Uttarakhand 3Nalanda University, Rajgir, Nalanda, Bihar *Email: sujata.upgupta1@gmail.com; profsarnam.singh@gmail.com
Online published on 10 May, 2021. Abstract An approach to generate the 3D model of individual standing trees and retrieve their biophysical parameters has been presented in this paper. The technology requires little user intervention and allows full or semi-automated external orientation of images, camera calibration and creation of 3D models based on image correlation techniques. Close range photographs of isolated trees taken from multiple angles were used. The 3D models generated were used to obtain measurements on tree height, crown base height and crown diameter. Accuracy and precision of the results were tested, and validated using conventional ground based measurements. It was found that the field observed and model estimated parameters were in good agreement and the error in measurement was 4.64% for height and 13.75% for crown diameter. The correlation coefficient between phytomass based on the field data and 3D modeled data was 0.7 for Eucalyptus sp. and 0.56 for Tectona grandis (Teak). More repetitive experiments and methodological studies particularly in forest ecosystem are required using very high-resolution close range digital photographs to understand the rate of growth, carbon pool assessment and carbon sequestration in forests with higher accuracies. Top Keywords Biophysical parameters, Close-range photographs, Digital camera, 3D model. Top |