RODRIGUEZ Maria Victoria
congresos y reuniones científicas
Response of vegetation to the increase in guanaco density after sheep removal in north-eastern Patagonian rangelands, Argentina
RODRÍGUEZ, MARIA VICTORIA; PAZOS, GUSTAVO; MARINO, ANDREA; LARREGUY, CECILIA
Congreso; International Rangelands Congress; 2016
International Rangeland Congress
In this work, we annually monitored during seven yearsthe cover and composition of four plant communities in a wildlife reserve thatwas previously a typical sheep ranch. After sheep removal at the time of thereserve creation, a rapid increase of guanaco density was registered (Marino etal., 2015).In general, all canopy variables showed temporaloscillations with significant both negative and positive deviations from themean. Canopy and perennial-grass cover showed similartemporal trends in all vegetal communities. Herbaceous community was the only one showingclear temporal trends, but only for the last two years: negative for totalcanopy and perennial-grass cover and positive for bare soil. For three plantcommunities we did not find evidence of vegetation deterioration due to guanacoovergrazing. In herbaceous community guanaco density correlated positively to bare soil and negatively to both plantcover variables. This community was the only one accupied for unterritorial guanacos.Plantcommunities supporting territorial family groups of guanacos did not show signsof overgrazing. Unterritorial male groups deserves further attention becausethe observed negative effect on plant cover could be counterbalanced by highpotential for medium-term displacement at landscape scale.