Hi Yassir

I suggest that you consider all NDVI data >0.1. You can see the figure 1 in Article Monitoring of irrigated wheat in a semi-arid climate using c...

by the way, your are working on which crop?

Rachid

Hi rachid, thank you very much for your kind help. I will have a look at the paper. The crop is bambara groundnut an underutilized legume scientific name is vigna subterranea.

You are welcome Dear Yassir,

I don't know this crop. But after having a look in Google, i confirm that you have to consider NDVI values >=0.1-0.2 especially if you want to take into account for the early growing stages.

* you have to be carreful with this threshold. it depends on your data type (sensor) and also on the soil type. In general, very low values of NDVI

Dear Dr. Hadria,

Yes that's exactly what i was thinking i need to take ndvi greater than 0.1 to minimize background reflectance more pronounced in early crop stages. My sensor is a modified commercial canon s100 camera with the blue filter removed to allow it to capture the NIR bands. Basically, it captures R,G and NIR bands. Yes i did take ground measurements also. So far, the results are very good with average NDVI slowly increasing and reaching maximum value at flowering after that constant decline indicating senescence and foliage loss. However, the increase in average ndvi isn't comparable to wheat and sorghum as my crop is different. The soil is sandy clay loam.

Thank you very much for your advice. I greatly appreciate,

Kind regards,

yassir

Hi Yassir,

I would consider a different indices like MSAVI2 or NDVI 705. They are better than using NDVI for vegetation.

You may want to check this out.

Article Investigating Surface Urban Heat Island Characteristics over...

Welcome Yassir.

good luck with your research.