HemiView Forest Canopy Image Analysis System by Delta-T Devices is developed to measure LAI in the woody canopies.
The device uses upward looking high resolution fish-eye camera to capture hemispherical photograph of the forest canopy. Measurements should be done preferably in evenly overcast or clear conditions. The instrument uses Norman and Campbell (1989) algorithm to calculate LAI, leaf angle distribution, angular distribution of gap frequencies with the help of HemiView analysis System.
The devise is suitable for rapid surveys of LAI in forested canopies; however, some studies report issues such as underestimated LAI, influence of woody components and/or under-storey canopy.
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Sidabras, N. & Augustaitis, A. Application Perspectives of the Leaf Area Index (LAI) Estimated by the Hemiview System in Forestry. Proc. Latv. Univ. Agric. 33, 26–34 (2015).
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