Predicting interaction processes behind distribution patterns of native and invasive salicaceae along the Río Negro, Patagonia

THOMAS, L.; BOZZI, J.; ZIEGENHAGEN, B; GALLO, L A; MARCHELLI, P; LEYER, I

Mar del Plata

Congreso; BIOLIEF 2ndWorld Conference on Biological Invasions and Ecosystem Functioning,; 2011

BIOLIEF

Willows of the Salix alba-Salix fragilis complex, Salix babylonica and its hybrids as well as some Populus taxa, native to Europe or Asia, are typical invaders of riparian floodplain ecosystems in Patagonia. Introduced to South America by European settlers, their distribution area has increased significantly along north-Patagonian rivers. These processes may have impacts on Salix humboldtiana, the only native woody species in this region. In this study, we will develop habitat distribution models for different life stages of native and invasive Salicaceae and two other important woody invaders (Eleagnus angustifolia and Tamarix ramosissima) including numerous abiotic factors e.g. elevation, flood duration, soil texture, location, island morphology and land use intensity. Data on species (presence/ absence, age class, abundance, dbh) and explanatory variables were gathered using a grid-based, stratified-randomized sampling design. The plots are located on islands of the upper and middle part of the Rio Negro characterised by varying land use intensities. The investigations aim to identify ecological niches and niche overlaps among the life stages of the different species, to assess the competition potential and to predict further vegetation dynamics.