Impacts of recent agriculture intensification on the weed communities of wheat crops in the Rolling Pampa (Argentina)

POGGIO, SANTIAGO L; CARREIRA, ANALÍA M; DE LA FUENTE, ELBA B

Kaposvár, Hungría

Congreso; 15th European Weed Research Society Symposium; 2010

European Weed Research Society

Floristic shifts in weed communities are a particular case of ecological succession reflecting temporal variations in soils, climate, and agronomic practices. In the Pampas of Argentina, weed communities have responded to several environmental changes since late 19th century. Particularly, agricultural systems have been profoundly transformed during the last two decades. For instance, the use of fertilizers and herbicides have increased, as well as the adoption of no-tillage and genetically modified crops. We studied the changes that the weed communities of wheat crops have experienced after the recent transformation of cropping systems in the Rolling Pampa. Using two sets of weed surveys carried out in 1996/1997 (n = 40) and 2003/2004 (n = 41), we compared species richness and floristic and functional compositions of the weed communities of wheat crops. Total species richness was 68 in 1996/1997 and 62 in 2003/2004. Mean species richness at field scale was lower in 2003/2004 (7 S.E.M. = 0.9) than in 1996/1997 (14, S.E.M. = 0.6, P