LAUSR

Abstract Pedogenic iron rich soils are prevalent worldwide covering approximately 1000 million hectares. These soils are fragile and prone to severe degradation, in many cases resulting in high erosion rates and formation of gullies. Restoration and revegetation practices face many barriers in degraded Acrisols, including low nutrient availability exacerbated by high iron concentrations. The objective of this work was to evaluate the performance of two tree species, Pinus pseudotrobus, and Fraxinus uhdei, growing in Acrisol soils in the presence of endo, ecto or both types of mycorrhizic fungi, in order to assess the effect of the interaction for management of degraded lands. The largest Fraxinus plants, those inoculated with both types of mycorrhizic fungi, accumulated three times more biomass than the smallest, and for Pinus the largest plants, those growing in soil with both types of fungi, had 1.5 times more biomass. Iron content in tissues of the Fraxinua uhdei plants was within that reported for plants in general (0.014%), and for Pinus pseudostrobus our values were higher for all treatments but within the same order of magnitude. For ecological restoration and other management purposes these results strongly suggest that dual inoculation or planting species that allow for both types of mycorrhizic fungi to be present in the soil can improve tree species performance and therefore facilitate the recovery process of heavily degraded sites.