An advisory code of good agricultural practice in the area of ammonia emission reduction was produced. Data on the structure and trends of emissions were presented. The Code presents solutions for a more efficient nitrogen cycle in agriculture, options for reducing emissions by regulating the protein content of diets for livestock (ruminants, pigs and poultry), options for reducing emissions from animal houses and animal manure stores, and options for reducing emissions from the application of livestock and mineral fertilizers. The 28-page code has been published in electronic format (ISBN 978-961-6998-40-6) and as a booklet (ISBN 978-961-6998-37-6). This is the first published professional code in the field that directly meets the NEC Directive requirement that the state establish a national code of good practice for the control of ammonia emissions. The electronic version of Advisory Code is published on the website of Agricultural Institute of Slovenia and on the website of the Ministry of Environment and Spatial Planning.
F.17 Transfer of existing technologies, know-how, methods and procedures into practice
COBISS.SI-ID: 304085760Online 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.
F.16 Improvements to an existing information system/databases
COBISS.SI-ID: 5686120Methods of processing digestate from agricultural biogas plants for use in the production of organic fertilizers are presented. Digestates can be processed in a variety of ways, most commonly mechanical and chemical processing methods are used. In terms of complexity and economy, mechanical processing methods are most suitable for farms. In mechanical methods, the method of separation of digestate is shown (separation of liquid and solid phase of digestate by means of different designs of separators). For separators, the energy consumption of kWh/kg of processed digestate and the advantages and disadvantages of different separation methods are given. The separation phase of the digestate (one or two-stage separation) is followed by additional processing by drying the separated digestate (different methods of drying and the use of renewable energy sources are possible). The dried separator is processed by the pelleting process into pelleted organic fertilizers. The energy consumption in kWh/kg of pre-processed digestate in pelleted organic fertilizers and the advantages and disadvantages of different versions of pelleting machines are given.
F.18 Transfer of new know-how to direct users (seminars, fora, conferences)
COBISS.SI-ID: 5745768The indicator, published in the series Environmental Indicators in Slovenia (Environmental Agency of the Republic of Slovenia), shows the development of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) emissions from agriculture in the period 1986-2019. The key message of the indicator is that greenhouse gas emissions, in particular methane and nitrous oxide, from agriculture decreased by 11.0% from 1986 to 2019. The largest declines occurred in pig and cattle production and in fertilizer application to agricultural crops. The rapid decline in emissions was typical of the early years of this period. After that, the decline slowed down. In 2019, Slovenia achieved the target (0.3% increase of greenhouse gas emissions compared to 2005) set by Operational programme for limiting greenhouse gas emissions until 2020 (increase by a maximum of 5% compared to 2005).
F.30 Professional assessment of the situation
COBISS.SI-ID: 62572803Nitrogen 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