Restoring overgrazed Chaco forest: do soil chemical properties change after different years of domestic livestock exclusion?

ARÉVALO E.V.; TÁLAMO, A.; MARTÍNEZ GÁLVEZ, M. F; CHÁVEZ ANA; CROCE JOHANNA; TRIGO, CAROLINA

Congreso; VII World Conference on Ecological Restoration; 2017

Extensive livestock grazing is a major conservation-management concern in many forests around the world .One way to restore overgrazed forests is with livestock exclusion .Nevertheless, we do not know experiments that evaluate the effectiveness of exclusions in the restoration of dry-forest of South America .Thus, we studied how soil chemical properties change with different years of livestock exclusion in a dry Chaco forest (NW-Argentina) .We installed livestock exclusion in 2007 and 2012 following a randomized block design .Three treatments were compared: continuous year-long livestock grazing (CG), grazing excluded for 2 years (2Y), and grazing excluded for 9 years (9Y) .We assessed the exclusion effects on a variety of soil chemical parameters .Results of the two-way ANOVA showed that there was no significant difference between treatments respect to pH, extractable-P, exchangeable-Na and C/N ratio (p>0 .05) .Surprisingly, in 9Y exclusion the organic matter, organic-C, total-N and exchangeable-K values were lower than those of the other treatments (p