Ecosystem activity
Vegetation activity as captured by NDVI from MODIS and LANDSAT images showed divergent temporal trends for croplands, native vegetation and wetlands (Table 2 and Figure 9). The long-term analysis of the whole El Morro catchment based on MODIS data revealed a decreasing greenness across the forests > grassland/pasture > cropland (all differences being significant with p<0.01, Table 2). An increased vegetation activity with time, and likely water transpiration, was observed comparing the second decade (2011-2020) with the first (2000-2010) with average greenings of 5.5 and 3.5 % for forests and grasslands/pastures, respectively. In the same temporal comparison, croplands and sediment deposits experienced a -1.1 and -6.7 % drops, respectively (Table 2). The catchment as whole, displayed a small decadal greenness increase of 1.3% as the previous contrasting trends compensated out, particularly between the dominant components of grassland/pastures vs. croplands (Table 2).
With the higher spatial resolution of LANDSAT imagery, we targeted vegetation types and change trajectories more precisely focusing on the shorter period that encompassed the last erosion episode and our field observations (Figure 9). Forest sustained the highest greenness throughout the whole period while croplands the most temporally variable.  Pre existing wetlands and new wetlands emerging in croplands, displayed a sustained and stable greenness raise (Figure 9). Deposits landed on croplands in 2015 showed a sharp greenness decline followed by a steady recovery that was still not completed but close to wetlands and croplands four years later. The single dried wetland location (site B), had a high greenness that matched that of forests until one year after the new incisions drained the area. After that time its greenness dropped steadily for three consecutive years approaching levels that are close to those in the recovering sediment deposits (Figure 9).