A Leaf Area Index visualization method using wireless sensor networks

Leaf Area Index (LAI) is one of indicators in observing plant growth. Continuous estimation of LAI can increase productivity of agriculture. Since LAI has high correlation with light transmittance into under-foliage, monitoring light transmittance makes it possible to estimate LAI continuously. In this paper, we present a design, implementation, and evaluation of a continuous LAI monitoring system. Our contribution is three-fold. First, through a preliminary experiment, we show that in order to accurately estimate LAI, it is necessary to properly determine measurement timing for avoiding effects from direct sunlight. Second, we provide design and implementation of a determination method of measurement timing of light intensity, and prove the accuracy of light transmittance measurement and LAI estimation. Finally, we demonstrate an application example of the system for determining the light absorption coefficients of different cultivars for further agricultural analysis.