Humid Pampas

The Humid Pampa (Spanish: Pampa Húmeda) is an extensive region of flat, fertile grassland of loessic origin in Argentina. It has a precipitation average of 900 mm per year, in contrast with the Dry Pampas to the west, which average less than 700 mm.

Like the Pampas in general, the region's terrain is predominantly hilly and of a temperate climate, though rich mollisols are more abundant here than to the west, where soils of loessic origin are more common. Except for a few bluffs near the Paraná and Río de la Plata rivers, as well as the Tandilia and Ventania mountain ranges to the south, the region's slope rarely exceeds 6 degrees. It covers Buenos Aires Province almost completely, the centre and south of Santa Fe Province, most of Córdoba Province and the eastern third of La Pampa Province, totalling at least 600,000 km².

The Uruguayan savanna, which lies east of the rivers in Entre Ríos Province of Argentina, Uruguay and the south of Brazil, is sometimes considered part of the Humid Pampa. The Uruguayan savanna is not as flat as the named aforementioned areas.

The flatlands are also interrupted by low hill's ranges like Tandilia in the southeast, namely at Sierra de los Padres, Balcarce, Olavarría, Tandil and like the higher system of the Sierra de la Ventana to the south, near Bahía Blanca. Finally, there are also some dunes at the Atlantic coast, such as at the city of Banderaló.

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