No abstract

Intensive agriculture operations increase emissions of harmful gases into the environment. According to scientists, as much as 83-91% of total ammonia emission to the environment is accounted for by livestock operations (Bluteau and Daniel, 2009; Sanz et al., 2010). The reduction of ammonia emissions is one of the most widely considered matters within modern farming. Ammonia emissions not only lead to poor quality of air in livestock barns, but also contribute to the acidification of soils and surface waters, eutrophication, deforestation, etc. (Erisman et al., 2008; Menzi et al., 2006; Pereira et al., 2010), which in turn have a major effect on the atmosphere, the environment and the sensitive natural ecosystem.

Increasing control of localized air pollution caused by ammonia is identified, including limiting the maximum emissions from agriculture. In EU countries, the agricultural sector is the source of above 94% of the total anthropogenic emissions of ammonia, of which manure removal systems account for 56%. In view of the reason for the agricultural waste management by formation and propagation of ammonia gas—the bacterial and enzymatic degradation of organic components in excrement—it is important to evaluate the effect of biotreatment of 100% natural composition (contain Azospirillum sp. (N) (number of bacterial colonies −1 × 109 cm−3), Frateuria aurentia (K) (number of bacterial colonies −1 × 109 cm−3), Bacillus megaterium (P) (bacterial colony count −1 × 109 cm−3), seaweed extract (10% by volume), phytohormones, auxins, cytokinin, gibberellins, amino acids, and vitamins) on the emission of ammonia from organic waste. Experimental research was carried out to determine significant differences of dynamics in agrochemical composition of manure, NH3 gas emissions, depending on biotreatment, manure storage duration, and ventilation intensity of the barn. Gas emission was obtained via laser gas analyzer using a spectroscopic method in a specially reconstructed wind tunnel chamber. About 32% manure biotreatment effect on reduction of ammonia emissions was established. The maximum effect of the biodegradable compound on gaseous propagation was assessed after 28–35 days of manure storage and proved all biotreatment effect time of 49–56 days. By the saving nitrogen loses priority, manure biotreatment could reduce nitrogen losses from manure and inorganic N fertilizers by approximately 5%, also could reduce approximately 5911.1 thousand tones nitrogen fertilizer in the world and reduce approximately 5.5 Eur ha−1. “The biotreatment impact assessment confirmed that proper application of biotreatment can reduce ammonia emissions from manure and environmental pollution from agriculture”.

Experimental data were applied for the modelling optimal cowshed temperature environment in laboratory test bench by a mass-flow method. The principal factor affecting exponent growth of ammonia emission was increasing air and manure surface temperature. With the manure temperature increasing from 4°C to 30°C, growth in the ammonia emission grew fourfold, that is, from 102 to 430 mg m−2h−1. Especial risk emerges when temperature exceeds 20°C: an increase in temperature of 1°C contributes to the intensity of ammonia emission by 17 mg m−2h−1. The temperatures of air and manure surface as well as those of its layers are important when analysing emission processes from manure. Indeed, it affects the processes occurring on the manure surface, namely, dehydration and crust formation. To reduce ammonia emission from cowshed, it is important to optimize the inner temperature control and to manage air circulation, especially at higher temperatures, preventing the warm ambient air from blowing direct to manure. Decrease in mean annual temperature of 1°C would reduce the annual ammonia emission by some 5.0%. The air temperature range varied between −15°C and 30°C in barns. The highest mean annual temperature (14.6°C) and ammonia emission (218 mg m−2h−1) were observed in the semideep cowshed.

The experimental studies were carried out in the most common cowsheds in Lithuania. The cowsheds involved in the research featured different insulation patterns and livestock keeping technologies where cows were kept tied or loose. The efficiency of ventilation system was measured in 7 cowsheds based on the variation in air temperature, air relative humidity (RH) and ammonia. The main problems of microclimate in Lithuanian cowsheds were found to be as follows: a high relative humidity resulting in water vapour condensation on the roof structures; the air temperature is regularly below the recommended minimum of -7 °C; the air temperature is regularly above the recommended maximum of 25 °C. Optimization of the microclimate in cowsheds concerned, it is recommended to adjust the ventilation intensity based on the difference of air temperatures within the barn and outdoors. During cold months of winter it is recommended to keep the air temperature in semi-insulated cowsheds by 8-11 °C higher than that outdoors, whereas in uninsulated box-type cowsheds with roof cementhigher by 5-7 °C, and in uninsulated box-type cowsheds with roof metalhigher by only 3-5 °C. During severely freezing periods of outdoor temperature, the air temperature was found not to drop below -7 °C only in insulated cowsheds. Whereas during extremely hot days when the outdoor temperature rises above 26-28 °C, the cowsheds of all types (those insulated and uninsulated) were found to be too hot for cows. Consequently, thermal insulation of a cowshed's roof and adjustment of the ventilation intensity are not sufficient for solving the problems caused by heat stress in the cowsheds.