3.1 Regional NDVI dynamics
Vegetation recovered on the MP between 2000 and 2015, and the area in which restoration was statistically significant exceeded that in which degradation predominated in each subregion during three equal subperiods (Table 2).
3.1.1 DSR
In the DSR, the overall change was more severe for the whole 2000–2015 period than that in each subperiod. The NDVI area with a statistically significant change (significant restoration and degradation) is larger than the sum of the NDVI changes from each period. The significant restoration area is more than 25% in the DSR between 2000 and 2015, and the vegetation recovery area is always larger than the degradation area during each period. This shows that vegetation activity was enhanced and the DSR experienced a period of vegetation restoration (Figure 3).
3.1.2 GSR
In the GSR, the extent and proportion of vegetation change over the entire period between 2000 and 2015 was greater than that in each subperiod (Figure 4). The significantly recovered area was more than 31% of the GSR. The area with vegetation restoration was always larger than that with degradation in any investigated time period. This shows that, overall, vegetation recovery occurred in the GSR over the study period.
3.1.3 FSR
Vegetation dynamics were more intense during the entire 2000–2015 period than in each subperiod in the FSR (Figure 5). The significant restoration area was more than 50% in the FSR. The significant recovery area was larger than that of the significant degradation area in each period, which shows that overall vegetation recovery occurred in the FSR over our study period.