Effect of tillage and crop management on runoff, soil erosion and organic carbon loss

Proper management of soil organic matter is an important issue in the context of sustainable agriculture. The intensification of production and the loss of organic carbon associated with agriculture reduce the efficiency of production and the quality of the environment, especially in relation to areas exposed to erosion. The aim of this study was to determine the impact of specific tillage systems and plant cover on the organic carbon losses, as well as on runoff and soil losses, over a 6-year study period following the introduction of no-till. The first factor in the experiment was the tillage system: conventional tillage (CT) and no-till (NT). The second factor was plant cover: horse bean, spring wheat and winter oilseed rape. The results showed that runoff was 4.3 +/- 0.6% higher under NT than under CT, while soil loss was 66.8 +/- 2.7% lower under NT than under CT. Compared to CT, NT limited the total organic carbon losses by an average of 46.0 +/- 2.9% and organic carbon bound with sediment losses by 53.2 +/- 0.7%, whereas for dissolved organic carbon, there were no significant differences for the tillage systems. The anti-erosion effectiveness of NT was lower in the first year, but it increased in subsequent years after the introduction of this tillage system. Plant cover also had a significant impact on organic carbon losses and soil protection. The crops were ranked according to runoff, soil losses and organic carbon losses in the following order from lower to higher losses: winter oilseed rape > spring wheat > horse bean.