## 3 Results  
### Seasonal Variability of Field Observations and Remote Sensing Data  
The seasonality in the data during the study period (2015-2017) can be seen in Figure 2. Some parameters evaluated present a phase with precipitation (i.e., soil moisture, stem growth and photosynthetic activity (EVI)), others present seasonal behavior in the phase with net radiation (i.e., litter and leaf flush (Gcc)). The most severe drought episode recorded in the study region using the SPI index was in 2003, as also observed by [64]. A light-level drought was recorded in RJA between November 2015 and May 2016, coincided with the occurrence of the 2015/2016 El-Nino event [8; 65]. However, the months with low rainfall lasted until July 2017 (Figure 2A,D). The total annual rainfall (\(\pm\)SD, standard deviation) for the period 1983-2017 had an average of 1926 \(\pm\) 141 mm. The confidence interval for precipitation determined for the wet season is 237.43 mm \(\leq\mu\leq\) 252.62 mm, and for the dry season it is 36.39 mm \(\leq\mu\leq\) 47.16 mm, with 95% confidence. The water table depth reaches the lowest quota in the transition between the dry and wet seasons (Sep.-Oct.), and fluctuated out of phase with the rains, with a delay (_Lag_) of 3 months (\(R^{2}\) = 0.83, \(p\)-value \(<\)0.001). This lag demonstrates that the wet season rainfall is crucial for groundwater recharge during the dry period (Figure 2B). The water table reaches its maximum limit at the end of the wet season, when rainfall and soil moisture decrease, taking about 4 months for the water table to recharge (Figure 2B). The production of total litter (leaves and miscellaneous) occurs throughout the year, but tends to show greater productivity during the dry period (Figure 2E). The production in the 2016 dry season was 9.13 Mg ha\({}^{-1}\), whose season comprises the period after the El-Nino drought, but with persistent negative rainfall anomaly. In the 2017 dry season, in which the rainfall pattern in the region was normal, litter production was 7.94 Mg ha\({}^{-1}\), representing a 13% decrease from one year to the other. In the wet season of 2016/17, the total litter production was 5.91 Mg ha\({}^{-1}\). The total litter production in 21 months of monitoring was 26.69 Mg ha\({}^{-1}\), which gives the RJA site an average annual production of 15.25 Mg ha\({}^{-1}\) yr\({}^{-1}\), in the period evaluated. The mean monthly production is 1.27 \(\pm\) 0.82 Mg ha\({}^{-1}\) mth\({}^{-1}\), and the confidence interval is 0.92 Mg ha\({}^{-1}\) mth\({}^{-1}\)\(\leq\mu\leq\) 1.62 Mg ha\({}^{-1}\) mth\({}^{-1}\). The total annual stem growth in RJA had an average of 0.18 \(\pm\) 0.15 cm (Figure 2F). During the 2015/16 wet season (0.16 cm), there was a higher stem growth compared to the 2016/17 wet season (0.09 cm) (\(p\)-value = 0.047, KW). In the 2016 dry season, stem grew 0.08 cm. The mean monthly stem growth is 0.015 \(\pm\) 0.01 cm, and the interval confidence is 0.011 cm \(\leq\mu\leq\) 0.019 cm. The diameter class DBH \(\geq\) 40 cm (0.19 \(\pm\) 0.18 cm) showed greater stem growth in the wet season of 2015/16 followed by the class 20-30 cm in diameter (0.16 \(\pm\) 0.11 cm), in the same period of 2016/17 the class of 30-40 cm (0.13 \(\pm\) 0.11 cm) showed the greatest seasonal increase. In the 2016 dry period, trees between 30-40 cm (0.10 \(\pm\) 0.13 cm) represented the diameter class with the greatest stem growth. In terms of stem growth, an increase trend was observed in the wet season compared to the dry season, whose seasonality was statistically significant (\(p\) = 0.007, KW). The EVI increases in mid-September and decreases in mid-February/March during the wet season (Figure 2G). Average EVI was 0.49 \(\pm\) 0.03, with interval confidence of 0.48 \(\leq\mu\leq\) 0.50. In Gcc, it is possible to identify 2 peaks in the values, one at the apex of the dry season and the other at the beginning of the wet season (Figure 2H, red line). Average Gcc was 0.49 \(\pm\) 0.01, with interval confidence of 0.494 \(\leq\mu\leq\) 0.496.