Alpine soils

Abstract

Alpine soils are found in mountainous regions above the natural subalpine tree line. This high-altitude belt is characterized by a lack of trees and dominance of a continuous grass carpet. The global land area covered by alpine soils is fragmented into many mountain regions (Rocky Mountains, Alps, Himalayas, Atlas, Andes, East Africa Mountains, New Guinea Highlands, New Zealand Alps, etc.) and approaches approximately 4 x 10(6) km(2). As a function of time, topographic conditions, and parent materials, a large range of soil types exists. However, alpine belt environment specificity leads to common features for all alpine soils. Because of the last glaciation, alpine soils are young (<10,000 years BP) and strongly influenced by a periglacial environment. On steep slopes, soils are often thin, regularly truncated, and in a constant process of rejuvenation. However, deep soils are found in some alpine grasslands on highly weatherable parent materials. Organic matter accumulation, acidification process, and a great role of aeolian dust deposition are other general characteristics of alpine soils genesis. The alpine soils are fragile and subjected to severe environmental threats, such as overgrazing, acid deposition, and climate change.