Land use in the dry subtropics: Vegetation composition and production across contrasting human contexts

BALDI, GERMÁN; JOBBÁGY, ESTEBAN G.

JOURNAL OF ARID ENVIRONMENTS

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Año: 2012 vol. 76 p. 115 - 127

0140-1963

Dry subtropical regions, originally hosting xerophytic vegetation, are currently characterized by diverseland cover/use patterns. Using existing biophysical and socio-economic databases, we explored howhuman contexts influenced land cover, vegetation composition and agricultural production in five distantregions. On average, cultivated areas represented a minor proportion (<16%) of all the regions, except inAsia (74%). This proportion was positively associated with population density when considering allregions together (slope ¼ 0.2 ha*inh-1), but the association became weaker in low-population regions.While protected areas displayed highly similar life-forms across regions, non-protected natural vegetationareas presented large contrasts, suggesting different imprints of land management. The observedcontrasts were more marked for cultivated vegetation, with different species and species diversitiesbeing found in each region. These contrasts likely reflect orientation toward national/global markets inthe Australian and American regions and toward local markets/subsistence in Asian and African regions.Africa and Asia were characterized by low and similar per capita levels of food production (w50 kggrain*y-1*inh-1 and w0.14 livestock units*inh-1), in contrast to South America and Australia (585 kggrain*y-1*inh-1 and 10.2 units*inh-1, respectively). This comparative perspective assisted in exploringthe reciprocal influences between social-economic development and ecosystems that lead to alternativestrategies of land management.