MSAVI2 and NDVI
The MSAVI2 vegetation index obtained from Sentinel 2 images showed
values between 0.023 and 0.096 (Fig. 5). The maximum values were found
in November and the minimum in May. The GAM fitted to the data had a
significant treatment effect (Table 4). During the analyzed period,
MSAVI2 in +W was not different from C except during summer when it was
higher than in C (Fig. 5A). MSAVI2 in +N and +NW was higher than in C
throughout the year (Fig. 5A).
The ground based daily NDVI values recorded from July 2019 to July 2020
ranged from 0.05 to 0.32, showing the maximum value in November and the
minimum value in June (Fig. 6A). The results of the GAM fitting
throughout the period (Table 4, Fig. 6A), as well as the results of the
ANOVA tested with all daily values (Table 3, Fig. 6B), indicated
significant effects of the treatments on NDVI. The treatments
significantly increased NDVI compared to the control
(p <0.0001), the effect being higher in +NW
(p <0.0001). It should be noted that the maximum
difference in NDVI between +W and C occurred in spring while it was much
lower in autumn and winter (Fig. 6A).