Assessing the impact of management practices on gas emissions and N losses calculated with denitrification-decomposition model

Abstract

The study presents the impact of management practices on greenhouse gas emissions (GHG) and nitrogen (N) losses calculated with a denitrification-decomposition model. Two cropping systems were analysed. The first rotation (A) consisted of potato, winter wheat, spring barley and corn. The second (B) included potato, winter wheat, spring barley and clover with grasses mixture. In A1 and B1 scenarios, fluxes were estimated on the basis of mineral fertilizers input, whereas in A2 and B2 scenarios the assessment of emissions was made with regards to manure. The results indicated that the application of manure in A rotation led to the increase of nitrous oxide (N 2 O) emission, N leaching, N surplus, crop yields, and the decrease of nitrogen use efficiency higher than in B rotation. Additional doses of manure in A2 scenario increased the potential of the accumulation of soil organic carbon (SOC) and global warming potential (GWP) by 157%. In B2 scenario, SOC augmented more than three-fold but GWP increased only by 10%. The N losses and GHG emissions could be minimised by controlling N application through the implementation of nutrient management plan in which N doses are defined based on the crop needs and soil quality.

Influence of Tillage Practices and Crop Type on Soil CO2 Emissions

“…Our study showed that tillage treatments affect soil CO2 emissions, which agrees with several other studies [15,39], where CO2 release varied with agricultural practices. Figure 3 presents two-year average soil C-CO2 emissions (n = 48) considering tillage treatments.…”

Assessment of nitrous oxide emissions from agricultural soils at local level in Poland

“…When formulating an action plan, it is necessary to pay particular attention to exploring the potential of agricultural and rural areas (including agricultural soils) in order to reduce GHG emissions. For example, Syp et al (2015), when assessing the impact of management practices on gas emissions and N losses calculated using the DNDC model, state that the N losses and GHG emissions could be minimized by controlling N application through the implementation of a nutrient management plan in which N doses are defined based on the crop needs and soil quality. However, as emphasized by Bennetzen et al (2016), agricultural GHG emissions can only be reduced to a certain level and a simultaneous focus on other parts of the food-system is necessary in order to increase food security whilst reducing emissions.…”