Agro ecosystems in a changing climate : adaption through crop rotations

Abstract: Climate change is a phenomenon that affects everyone. It is thus of high relevance to gain knowledge in how the farms that supply society with food will be affected and what adaptations can be made to minimise negative effects on field level. Götaland is expected to have a longer vegetation period in the years 2011-2040, but Southern Sweden is expected to continue to have frost days. The periods with draught spells will probably be longer and the periods of intensive and continuous rain are expected to increase. C3 crops, such as oat and onion, as well as many weeds are expected to respond to an increase in CO2 concentration and temperature with increased growth. Crops with unlimited growth, such as carrot and sugar beet are expected to respond most in accumulation of weight. Plant nutrient content is likely to change, with a decrease in protein as the CO2 concentration increase. A change in pest and prey population is expected, which makes it highly relevant to create habitats for the prey. Diseases spread by insects, such as viruses, are believed to increase in extent. Water logging and leaching will have to be addressed as heavy rainfall is expected. A survey among farmers showed that many problems on the field level could be reduced with changes in crop rotation, or by adjustments in the surroundings. Some farmers are already using techniques and crops to decrease problems that are expected to worsen, and in the present study, several adjustments were suggested that could further improve their situation.