Short- and long-term effects of shrub management on vegetation in the Monte, Argentina

A comparison was made of plant cover, carrying capacity and diversity in areas of Monte vegetation at the Biosphere Reserve of Ñacuñán, Mendoza, Argentina, in 1982, 1984 and 1995. Treatments applied in 1981 were: control (untreated plots), selective hand-cutting, roller-chopping, and root-plowing. By 1995, woody cover was lower in root-plowed plots (27%) than in the others treatments (41–51%), and herbaceous cover was similar in treated (28–39%) and untreated areas (26%). Carrying capacity of treated areas (6–8 ha per Large Stock Unit (LSU)) was higher than in the control areas (12 ha LSU−1). Woody species diversity, quantified by the Shannon index, for both areas was similar in the study period (0•62), except in root-plowed sites in 1982 (0•0) and 1995 (1•3). Herbaceous species diversity was similar on treated (0•81) and untreated sites (1•2) in 1995. We could recommend less drastic treatments to improve carrying capacity