Soils from the Highlands

Abstract

The Andean Highlands are made of the western and eastern cordilleras arranged in a north–south direction, with very steep outer slopes characterized by a gradual decline in altitude as they diffuse into the coastal plain or the Amazonia , and a decreasing massiveness also from north to south. Highlands are divided into three regions: Northern, Central, and Southern Highlands. The northern part received recent contributions of volcanic projections (ash and lapilli) over which diverse fertile and generally deep Andisols have developed, characteristics closely linked to climate and parent material. The Central Highlands do not have active volcanoes or recent pyroclastic projections and parent material consists of old volcanic and metamorphic rocks in a monotonous relief. There are a variety of soils in this zone depending on the altitude. In the upper sectors, soils are ferralitic–fersalitic, in the middle, they are moderately evolved with mollic or vertic features, and in the lowland, the soils are poorly developed (Inceptisols and Entisols) . Southern Highlands are characterized by a more rugged relief over granites, metamorphic formations, tertiary sediments , and glacis of colluvial deposits that have formed, in the upper parts, fersiallitic saturated soils are rich in minerals 2:1, along with desaturated ferralitic Paleosols . In the lower areas, soils are mainly vertisoles, often poorly developed, surrounded by the fersiallitic Paleosols.