Towards an Optimized Method of Olive Tree Crown Volume Measurement

Sensors

Antonio Miranda-Fuentes¹  Jordi Llorens¹  Juan L. Gamarra-Diezma¹  Jesús A. Gil-Ribes¹ 

[1] Dpto. de Ingeniería Rural, Área de Mecanización y Tecnología Rural, Universidad de Córdoba, 14005 Córdoba, Spain; E-Mails:

关键词: terrestrial LiDAR;    canopy characterization;    olive tree;    tree crown volume;   

DOI  :  10.3390/s150203671

来源: mdpi

【 摘 要 】

Accurate crown characterization of large isolated olive trees is vital for adjusting spray doses in three-dimensional crop agriculture. Among the many methodologies available, laser sensors have proved to be the most reliable and accurate. However, their operation is time consuming and requires specialist knowledge and so a simpler crown characterization method is required. To this end, three methods were evaluated and compared with LiDAR measurements to determine their accuracy: Vertical Crown Projected Area method (VCPA), Ellipsoid Volume method (V_E) and Tree Silhouette Volume method (V_TS). Trials were performed in three different kinds of olive tree plantations: intensive, adapted one-trunked traditional and traditional. In total, 55 trees were characterized. Results show that all three methods are appropriate to estimate the crown volume, reaching high coefficients of determination: R² = 0.783, 0.843 and 0.824 for VCPA, V_E and V_TS, respectively. However, discrepancies arise when evaluating tree plantations separately, especially for traditional trees. Here, correlations between LiDAR volume and other parameters showed that the Mean Vector calculated for VCPA method showed the highest correlation for traditional trees, thus its use in traditional plantations is highly recommended.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.