Impact of invasive Acacia longifolia and Populus alba on native flora and fauna of a coastal natural grassland.

ALBERIO, C. ; O. STELLATELLI; V. COMPARATORE ; L. VEGA

Rosario

Congreso; IX International Rangeland Congress; 2011

Introduction The advance of exotic tree species is one of the main threats to conservation of the last relicts of natural grasslands in South America (Cuevas & Zalba, 2009) and represents the introduction of a completely new lifeform to the ecosystem. The aim of this work was to study the impact of the invasion of Acacia longifolia and Populus alba on the cover and richness of plant species, the abundance and microhabitat use by the sand dune lizard Liolaemus wiegmannii between invaded and non-invaded areas in a coastal ecosystem included in the Pampean Grassland District. Materials and Methods The study area has 3,4km2 and is located at Mar Azul (S37º20´45,8´´-W057º03´17,9´´), Bs. As., Argentina. The ambient was sub-divided in 4 strata: invaded by acacia (acacialaan), poplar (mall), acacia-poplar (mixed) and not invaded (grassland). In 204 sample areas of 4m2 distributed randomly, the cover of each vegetal species was registered, also they were grouped according to their physonomy (Cabrera & Zardini, 1978). For lizard sampling, 32 lineal transects of 50m long were distributed randomly. The number of individuals and the vegetal species utilized by reptiles were registered. Results & Discussion A total of 31 plant species were found, 26 of them were native. The grassland had a higher richness of native plant species (Dunn: p