Deriving seasonal dynamics in ecosystem properties of semi-arid savannas using in situ based hyperspectral reflectance

The analysis of effects of varying sun / sensor geometry has been done over 15 days (of which 3 have been removed) during the peak of the growing season. This misses the highest zenith angles and times of different vegetation conditions. I suggest to repeat the analysis for other time periods as well to gain a full picture of sun / sensor geometry effects. Furthermore, why have only NDSIs been investigated and not the reflectances themselves? This information would help to understand the behaviour of the NDSIs and would support the claim in the discussion that NDSIs reduce angular effects.

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