Automatic estimation of olive tree dendrometric parameters based on airborne laser scanning data using alpha-shape and principal component analysis
Edyta Hadaś , Andrzej Borkowski , Javier Estornell , Przemysław Tymków
AbstractThe aim of this study is to present an automatic approach for olive tree dendrometric parameter estimation from airborne laser scanning (ALS) data. The proposed method is based on a unique combination of the alpha-shape algorithm applied to normalized point cloud and principal component analysis. A key issue of the alpha-shape algorithm is to define the a parameter, as it directly affects the crown delineation results. We propose to adjust this parameter based on a group of representative trees in an orchard for which the classical field measurements were performed. The best value of the a parameter is one whose correlation coefficient of dendrometric parameters between field measurements and estimated values is the highest. We determined crown diameters as principal components of ALS points representing a delineated crown. The method was applied to a test area of an olive orchard in Spain. The tree dendrometric parameters estimated from ALS data were compared with field measurements to assess the quality of the developed approach. We found the method to be equally good or even superior to previously investigated semiautomatic methods. The average error is 19% for tree height, 53% for crown base height, and 13% and 9% for the length of the longer diameter and perpendicular diameter, respectively.
|Journal series||GIScience & Remote Sensing, ISSN 1548-1603, (A 30 pkt)|
|Publication size in sheets||0.95|
|Keywords in English||remote sensing; airborne laser scanning; alpha-shape; principal component analysis; agriculture; trees|
|Internal identifier||64131; PX-5a0d4cccd5de60d919fdc790|
|Score||= 30.0, 10-07-2020, ArticleFromJournal|
|Publication indicators||= 2; = 5; : 2017 = 1.053; : 2017 = 2.852 (2) - 2017=2.195 (5)|
|Citation count*||8 (2020-09-26)|
|Uwagi||This article was originally published with errors. This version has been corrected. Please see erratum (https://doi.org/10.1080/15481603.2017.1355643)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.