IFEVA   02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
artículos
Título:
Climate change impacts on South American Rangelands
Autor/es:
LAURA YAHDJIAN; OSVALDO E. SALA
Revista:
Rangelands
Editorial:
Society for Range Management
Referencias:
Lugar: Colorado; Año: 2008 vol. 30 p. 34 - 39
ISSN:
0190-0528
Resumen:
South American Rangelands cover 33% of the area of the subcontinent. Rangeland productivity and species composition are directly related to the highly variable amounts and seasonal distribution of precipitation and only secondarily controlled by other climatic variables. Primary production increases linearly with annual precipitation and livestock biomass increases linearly with primary productivity, resulting in a direct relationship between annual precipitation and livestock biomass. South American Rangelands sustain pastoralist activities, subsistence farming, and commercial ranching and are a key factor in the economy of many countries. As predicted by current climate-change models, all of South America is very likely to warm during this century and mean temperature may arise 2° C by 2020. Annual precipitation is likely to decrease in the southern Andes, to increase in Tierra del Fuego during winter and to increase in the Pampas region during summer. The frequency of occurrence of weather and climate extremes in South America is likely to increase in the future, which, in turn, will affect current and future primary production. Whereas livestock production may increase in the pampas region as a consequence of precipitation increases, livestock production could be negatively affected by higher temperatures or increased evapotranspiration rates. We propose development of Rangeland Alarm Systems (RAS) to alert land managers of impending droughts and the consequent forage shortage that may lead to short-term economic losses and long-term ecosystem deterioration.