in Italy there is a public research group that worked on MicroNIR (https://www.researchgate.net/publication/359004603_Use_of_Near_Infrared_Spectroscopy_for_estimation_of_Nitrogen_Credits_of_different_Cover_Crops ) calibrations to estimate the nitrogen ratio for cover crop aerial biomass in the field.
Have you ever thought about a technical approach of this type with your instrument?
We are working on similar approaches to mineral measurements, but not particularly N. We have no calibrations or wet chem measurements for Nitrogen currently and therefore we can’t train a model. In short, creating this models is technically possible, but we haven’t done it and we don’t have the needed material.
Our device (let’s call it UV/VIS) is a fast handheld device that works on 10 bands and is therefore less accurate in the spectral measurement than a NIR device like the one you are mentioning. In consequence, the typical model precision you get is lower, currently on the levels needed to make an in field decision but probably not for experimentation that relies on the measures to study further dimensions that will introduce their own noise.
The datasets we are sharing do have carbon measurements, though, and we are working on models for soil Carbon.
If you are interested on this line of work from a modelling perspective, we do have NIR measurements and several crop elements measured in our datasets, so you can evaluate NIR modelling for crop elements but not particularly Nitrogen. It can be used as a meta model trainer or for a study in feasibility.
Also the UV/VIS Reflectometer currently can be used to measure NDVI and estimate Chlorophyll Content. Both measurements can be indicators of leaf N content and overall plant health. This is mature work on our side that we can share if you are interested.
I am very interested.
As an agricultural technician I have a small laboratory (a centrifuge, a Hanna Instr. Bench reflectometer, a vortex). I consult farmer with Pfeiffer chromatographic analyzes (together with other laboratories I have formed a working group with which we do ring tests), POXC (Permanganate Oxidazable Carbon), mineral nitrogen (which I associate with the use of models, in particular use STICS of the French INRAE), and I have the carbon and total nitrogen done by another laboratory, and then obviously spade tests.
In my little one, I start to have a certain amount of data, in a fairly confined region (which has very advanced public soil maps available).
In one farm we started working with FarmOS, with the idea of storing all the data of the field practices.
I normally use R.
Only problem: at the moment “we are” alone, and the days are at most 24 hours, and I am not a researcher but a field technician.
But I am really very interested, also because the public administration of our region is spending a lot with the 4x1000 project.
How can I start?
Hello, Enrico! I’m very sorry I didn’t see your reply. Are you still interested on this. I’m guessing we could meet and I could show you some resources we have.