Altitudinal characterization, use and conservation of subtropical Yungas of Argentina

Abstract

Malizia,  L.,  Pacheco,  S.,  Blundo,  C.,  Brown,  A.D.  (2012).  Altitudinal  characterization,  use  and  conservation  of  subtropical Yungas of Argentina. Ecosistemas 21(1-2):53-73

Subtropical Yungas are distributed in northwestern Argentina and southern Bolivia over approximately 56000 km2. This vegetation type expands across a large altitudinal gradient (400-2300 m asl), where tree species turnover promotes the occurrence of three altitudinal belts (pre-montane forest, lower montane forest and upper montane forest), with associated changes in leaf phenology and dispersal syndromes. Deciduous tree species are dominant at the extremes of the gradient, and semi-deciduous and evergreen species are  dominant at mid elevations. Alternatively, wind- and gravity-dispersed tree species characterize the lower part of the gradient, while animal-dispersed trees characterize the upper part of the gradient. Physical and biological changes along the altitudinal gradient determine uses and conservation strategies. Deforestation of subtropical Yungas reached 18% of the original distribution in Argentina during the 1970’s, and raised up to 31% by  2010,  mainly  (>90%) over low and flat areas. To date, 22% of the current distribution of Argentinean Yungas is formally protected (at national, provincial and municipal levels), not  including international categories that may prove useful if sustainable-use criteria are successfully implemented. Additionally, land-use plans articulated with economic compensations might play a key role for planning regional use and conservation of subtropical Yungas.