I am new in remote sensing, and I would like to ask the community what are some good methods to calculate the Leaf Area Index (LAI) using Remote Sensing Data, for agriculture mostly applications.
closed as too broad by Andre Silva, PolyGeo♦ Feb 28 '16 at 0:01
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The methods to calculate LAI vary greatly with the data you want to use. Calculation by combining multispectral data and in-situ measurements use different methods than ones based on high-res LiDAR data or hyperspectral images.
I'd suggest you start out by reading a review about the topic, such as:
Zheng& Moskal (2009): Retrieving Leaf Area Index (LAI) Using Remote Sensing: Theories, Methods and Sensors. Sensors. doi:10.3390/s90402719.
This article is Open Access and accessible by anyone.
Then you need to either select a method and start collecting the necessary data or you already have data and select a method that works with your dataset.
While it is not my area of expertise, I have read a couple of articles that rely on the PROSAIL model.
LAI is not a directly observable parameter, so it has to be modeled based. Depending on your area of interest, and forest composition, you may be able to do something simple, like a regression between a standard vegetation index (such as NDVI, EVI or SAVI) and in-situ LAI measurements, or you may have to go through a physical model like PROSAIL.