The members of the project group prepared expertises for some of the strategic documents in the field of agricultural emissions into the air, including projections until 2050. These are the Comprehensive National Energy and Climate Plan (NEPN, adopted Feb. 27, 2020), the Long-term Climate Strategy (in inter-ministerial coordination) and the Operational Program for maintaining ambient air quality (in inter-ministerial coordination).
F.34 Consultancy
Online information system CATTLE.si stores milk production and reproduction data for about 3.370 Slovenian farms. These farms keep about 80% of total Slovenian dairy cow population. Farmers are regularly informed on the results by means of printed materials, web application, e-mails or SMS messages. Milk production data include also records on N excretion which is estimated on the basis of milk production and milk urea concentration (MUC). The information on MUC on the level of individual cow is recorded once a month in a frame of milk recording scheme. The participating farms are relatively small, i.e. 23.5 of dairy cows per farm on average. Over the period 2005-2018, the average MUC declined from about 20.0 to 18.5 mg/100 ml while the average milk production increased from about 5,800 to 7,300 kg per year. In a few years after 2005, when MUC measurements were introduced, the proportion of samples with MUC above the recommended value (30 mg/100 ml) declined from 15% to less than 10%. On the other hand proportion of milk samples below the recommendations (15 mg/100 ml, between 20 and 35 % of total number of samples) remained stable. According to the results of 3.4 million records obtained between the years 2014 and 2018, the highest MUC can be found during the summer/early autumn months (from July to September; averages from 20.2 to 20.4 mg/100 ml) and the lowest during the winter months (from November to March; averages from 17.6 to 17.8 mg/100 ml). Spatial analyses showed that high MUC can be found on farms in hilly areas which are characterised by a high proportion of grassland forage in diets. During the period 2005-2018 the estimated N excretion per cow increased (from 103 to 115 kg N per year) while the N excretion per kg of milk production decreased from 17.5 to 15.8 g (data from regression analyses). From 2014 to 2018 Holstein-Friesian cows were characterised by a lower N excretion (15.0 g per kg milk) than Simmental (17.1 g per kg milk) and Brown Swiss cows (17.6 g per kg milk). On the basis of MUC it was estimated that over 97% of dairy cows in Slovenia are given diets containing less than 140 g of crude protein per kg (on an 88% dry matter basis). The 140 g of crude protein per kg is an indicative value for low protein diets as suggested by Framework code for good agricultural practice for reducing ammonia emissions (UNECE, 2015). It was concluded that milk urea concentration can serve as a tool to reduce the nitrogen footprint of milk production. This is especially important in the case of small scale milk production, where diet formulation on the basis of forage analyses may not be feasible.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 5686120Nitrogen flows in Slovenian agriculture were quantified. All inputs (mineral fertilizers, animal fertilizers, other organic fertilizers, atmospheric deposition, biological fixation, seed and seedling input) were taken into account. Nitrogen losses with NH3, N2O, NO, NO2 and N2 into the air were estimated according to sources (animal houses, manure stores, grazing, fertilization with animal and mineral fertilizers). The nitrogen balance at the national level was presented. The main routes of nitrogen leakage from the agricultural system were identified and solutions for reducing economic and environmental damage were suggested.
B.04 Guest lecture
COBISS.SI-ID: 5696616