Potential impacts of climate change towards agricultural systems in South Brazil

Abstract

Recently there has been a growing concern regarding the impacts of the abnormal increase of the temperature of terrestrial surface. Changes in climatic patterns may incur limitations towards the agricultural production systems. In this context, the present work aims to discuss the effects of air temperature towards oat phenology and its impacts on the production systems in Rio Grande do Sul State, Brazil. The daily air temperature data were used from a historical observation series for the period 1970 to 2007, while phenologic data were extracted from breeding experiments from 1981 to 2007. Linear regression analysis was used to verify the occurrence of changes over the annual average of the daily mean, maximum and minimum air temperature, along with the number of days and the thermal sum from the emergency to the flowering of oat. The results showed that, although there has been no significant change of the average air temperature over the observation period, climate extremes seem to have been intensified. Regarding the phenology of oat, the main effect was observed in genotype changes. Inter-annual oscillations in temperature and the crop cycle showed to be the major risk factors towards agricultural activities.