We are anticipating to use PIX4D Field quite a bit this year on our experiments. One of them will be a Canola Photosynthesis trial. Here we will collect data on 180 genotypes of canola. The first bunch of data will be canopy cover. We want to know which lines will close the ground faster. For canopy cover, which index to do you think will be recommended (NDVI?). Is there some literature about this that I can follow?
For your Canola Photosynthesis trial, NDVI (Normalized Difference Vegetation Index) is indeed a suitable index to measure canopy cover. NDVI is widely used to assess plant vigor, biomass, and canopy cover, as it takes into account the difference between near-infrared (NIR) and red light reflectance from the plant canopy.
To calculate NDVI, you can use the following formula:
NDVI = (NIR - Red) / (NIR + Red)
In your case, you can use PIX4Dfields to create NDVI maps based on the multispectral data you collect from your drone flights. By comparing NDVI values across different genotypes, you can determine which lines close the ground faster and better understand their growth patterns. For that use the annotation tools, to draw your plots, that will allow you to get plot average index data you can use for ranking the different varieties.
Here is a source for further reading:
Agricultural Applications of High-Resolution
Digital Multispectral Imagery: Evaluating
Within-Field Spatial Variability of Canola
(Brassica napus) in Western Australia
Thank you Julius,
You are a great man. I am new to this type of data collection. we are expecting to have our Mavic 3 multispectral within the next 3 weeks. Once I get the first flights I might need to contact you again.
Thanks again for your feedback.
We are happy to help, we love that stuff as much as you do :). Here is a video which should give you an idea how to use the annotation tools in PIX4Dfields to get your plot level data (at minute 5:30):
You demonstrate importing geometry shape files, but where are these obtained from? Geometry files for what?
You either get them from you client or you created them in a GIS system like QGIS or Google Earth, we support .kml ; shapefile and .geojson.
Thanks. I tried Google Earth and exported a boundary, but get this error message when importing the kml file. Is that expected?
Make sure the boundary does not contain any error when drawing it (complicated edges).
Try creating a simple geometry and importing it in PIX4Dfields. If it fails, please share the file with us so we have a look.