Search Results
The Effect of Diet and Farm Management on N2O Emissions from Dairy Farms Estimated from Farm Data
The N2O emissions of 21 dairy farms in Germany were evaluated to determine the feasi-bility of an estimation of emissions from farm data and the effects of the farm management, along with possible mitigation strategies. Emissions due to the application of different fertilisers, manure storage and grazing were calculated based on equations from the IPCC (Intergovernmental Panel of Climate Change) and German emission inventory. The dependence of the N2O emissions on fertiliser type and quantity, cultivated crops and diet composition was assessed via correlation analysis and linear regression. The N2O emissions ranged between 0.11 and 0.29 kg CO2eq per kilogram energy-corrected milk, with on average 60% resulting from fertilisation and less than 30% from fertiliser storage and field applications. The total emissions had a high dependence on the diet composition; in particular, on the grass/maize ratio and the protein content of the animal diet, as well as from the manure management. A linear model for the prediction of the N2O emissions based on the diet composition and the fertilisation reached a predictive power of R2 = 0.89. As a possible mitigation strategy, the substitution of slurry for solid manure would reduce N2O emissions by 40%. Feeding cows maize-based diets instead of grass-based diets could reduce them by 14%. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Impact of chars and readily available carbon on soil microbial respiration and microbial community composition in a dynamic incubation experiment
The carbonisation of biomass and organic residues is discussed as an opportunity to store stabilised carbon compounds in soil and to reduce mineralisation and the emission of CO2. In this study, pyrolysis char (600 °C, 30 min) and hydrothermal carbonisation char (HTC char; 210 °C, 23 bar, 8 h), both derived from maize silage, were investigated in a short-term incubation experiment of soil mixtures with or without readily available carbon (glucose) in order to reveal impacts on soil microbial respiration and community composition. In contrast to pyrolysis char, the addition of HTC char increased respiration and enhanced the growth of fungi. The addition of glucose to soil-char mixtures containing either pyrolysis or HTC char induced an additional increase of respiration, but was 35% and 39% lower compared to soil-glucose mixtures, respectively, providing evidence for a negative priming effect. No significant difference was observed comparing the soil mixtures containing pyrolysis char + glucose and HTC char + glucose. The addition of glucose stimulated the growth of most microbial taxa under study, especially of Actinobacteria at the expense of fungi. Adding pyrolysis or HTC char to soil induced a decline of all microbial taxa but did not modify the microbial community structure significantly. Addition of pyrolysis or HTC char in combination with glucose however, increased the abundance of Actinobacteria and reduced the relative abundance of Acidobacteria and Betaproteobacteria while fungi were further increased in case of HTC char. We conclude that both chars hold the potential to bring about specific impacts on soil microbial activities and microbial community structure, and that they may compensate the variations induced by the addition of readily available carbon.
Metadatenschema für Schulungsmaterialien zum Thema Forschungsdatenmanagement
Das Dokument enthält ein Metadatenschema für Schulungsmaterialien zum Thema Forschungsdatenmanagement. Dieses Schema wurde von der UAG Schulungen/Fortbildungen der DINI/nestor AG Forschungsdaten erstellt und bei der Materialsammlung von FDM-Schulungsmaterialien unter https://rs.cms.hu-berlin.de/uag_fdm/ umgesetzt.