Table 2.
Main physical characteristics of the focal regions used to evaluate NDVI trends results. Acronyms: MAP, Mean annual precipitation; MAT, Mean annual temperature; MAPET, Mean annual potential evapotranspiration; AR, Argentina; BR, Brazil, CL: Chile; UY, Uruguay. Ecoregion name following Olson et al. [87], climatic information was extracted from CRU 2.0 [88] and soil type and land form from the SOTER-Latin America and the Caribbean [89] databases. The potential evapotranspiration was calculated using the same database and following Penman-Monteith method [90]. The calculation of the areas affected by changes was extracted from the superposition of the three series' average NDVI.
| Region | Eastern Paraguay | Western Bahia –BR | Uruguay River margins – AR, UY | Northern Chilean deserts | Patagonian Andes –AR, CL |
|---|---|---|---|---|---|
| Area affected (km2) | 83,300 | 65,700 | 3,400 | 24,400 | 370,000 |
| MAP (mm) | 1500-1800 | 1050-1750 | 1100 | 0-50 | 700-4500 |
| MAT (°C) | 21.0-23.5 | 23.0-24.5 | 18.0 | 13.0-15.0 | 5.0-7.0 |
| MAPET (mm) | 1200-1300 | 1400-1450 | 1150 | 1150-1350 | 500-850 |
| Soils | Acrisol, Arenosol | Ferralsol | Phaeozem, Vertisol | Regosol, Solonchak, Leptosol | Andosol, Cambisol, Leptosol, Phaeozem |
| Land forms | Plains to medium- gradient hills | Plateaus | Plains | Depressions to medium-gradient hills | Medium to high gradient hills and mountains |
| Ecoregion (and vegetation type) | Alto Paraná Atlantic (moist) Forest | Cerrado woodlands and savannas | Humid Pampa (prairies and grass steppes) and Uruguayan Savanna | Atacama Desert | Magellanic subpolar and Valdivian Temperate forests |
| Land use | Diversified dryland agriculture and grazing | Diversified agriculture with irrigation | Tree plantations and grazing | Negligible | Conservation, grazing and wood extraction |