Monte Desert Monte Desert The Monte Desert is a South American ecoregion, lying entirely within Argentina and covering approximately the submontane areas of Catamarca, La Rioja, San Juan, San Luis and Mendoza Provinces, plus the western half of La Pampa Province and the extreme north of Río Negro Province. The desert lies southeast of the Atacama Desert in Chile, north of the larger Patagonian Desert, east of the Andes and west of the Sierra de Córdoba. The delineations between the Monte Desert, the Atacama Desert, and the Patagonian Desert are not exact and the desert seems to be more-or-less continuous with the
Monte Desert other two nearby deserts. The geography of the land is very similar to that of the interior Patagonian Desert, with volcanic sediments, piedmont plains, large mountain blocks and many usually dry salt lakes. The major river is the Río Colorado and its tributary the Río Desaguadero, which meet in the south of the region and provide its principal source of irrigation water for wine crops. Due to the region lying on the eastern, or leeward, side of the Andes and west of the Sierra de Córdoba, it experiences very little rain. These rain shadow effects are the primary reason for