Leaf Area Index (LAI) Definition
The one-sided green leaf area per unit ground surface area under broadleaf canopies. For example, if all the green plant leaves in a 10 m² area have a one-sided leaf area of 10 m², then the LAI = 1.0; if the leaves in a 10 m² area have a one-sided leaf area of 20 m², the LAI = 2.0.