Afforestation with ‘multipurpose trees’ in ‘media lunas’, a case study from the Tarija basin, Bolivia

Abstract

Human-induced soil erosion has already affected all of the potential farming land in the Tarija basin/South Bolivia. It is described as an afforestation method involving ‘media lunas’ and multipurpose trees, whose implementation is associated with a high degree of mobilization of the target group.

On sites where a sufficient number of media lunas have been established, surface runoff is drastically reduced. They diminish the risk of failure of newly planted trees during frequently occurring dry phases, and promote their growth by preventing excessively large fluctuations in the soil-water balance and increasing soil moisture in general. Mostly indigenous multipurpose trees (Acacia and Prosopis) serve to stabilize erosion-prone sites on a long-term basis, and become invaluable because they provide a source of firewood, improve the soil, and yield protein-rich livestock forage during dry season. Media lunas provide more favorable conditions for natural vegetation.