Peatlands of the Central Andes Puna, South America

Abstract

The Andean puna is the highest elevation mountain and plateau region in the western hemisphere, extending from northern Peru to central Chile and Argentina, with vast areas above 4,250 m elevation. The Atacama Desert on the western side of the Andes is the world’s most arid region, and this aridity extends across the mountains. The upland vegetation is mostly continuous in the more humid north but becomes more and more patchy and barren composed only of bunch grasses in the central and southern region. Extensive upland talus, moraines, and colluvial deposits of the mountains produces perennial ground water flow systems that support thousands of peatlands and other wetlands that are regionally termed “bofedales” or “vegas”. The peatlands are dominated by several species in the family Juncaceae, most famously Distichia muscoides, that forms dense clonal cushions that characterize the alpine peatlands and landscapes. Being close to the equator, the growing season extends across the entire year, and continuous growth of the cushion plants have produced high carbon accumulation rates and peat bodies 7-10 m thick in many areas. The region supports unique plants and animals, and ecosystems, and the wetlands are threatened by overuse for livestock grazing, and climate changes that could reduce water provision may lead to some bofedales completely drying.