ABSTRACT
Several important changes in climate and crop production trends have been detected in Southeastern South America since the late 20th century. The climatic changes are characterized by increases in precipitation (up to 50 per cent in some areas); decreases in maximum temperature, especially during spring and summer; and increases in minimum temperature during most of the year (Castañeda and Barros, 1994; Barros et al, 2000; Pinto et al, 2002; Bidegain et al, 2005; Magrin et al, 2005). In response to the favourable climate trends, a subsequent significant increase in crop production, especially in the yield of rain-fed crops, has been noted. Magrin et al (2005), in comparing the period from 1950 to 1970 with that from 1971 to 1999, calculated a 38 per cent increase in soybean yields and an 18 per cent increase in maize yields attributable to the changes in climate (isolated by using crop simulation models with the same production technology).
