Emission of Greenhouse Gases and Odorants from Pig Slurry - Effect on the Environment and Methods of its Reduction

Abstract

Pig slurry is classified as a natural liquid fertilizer, which is a heterogeneous mixture of urine, faeces, remnants of feed and technological water, used to remove excrement and maintain the hygiene of livestock housing. The storage and distribution of pig slurry on farmland affect the environment as they are associated with, among others, the emission of various types of gaseous pollutants, mainly CH4, CO2, N2O, NH3, H2S, and other odorants. Methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O) are greenhouse gases (GHGs) which contribute to climate change by increasing the greenhouse effect. Ammonia (NH3) and hydrogen sulfide (H2S) are malodorous gases responsible for the occurrence of odour nuisance which, due to their toxicity, may endanger the health and lives of humans and animals. NH3 also influences the increase of atmosphere and soil acidification. The article presents the environmental impact of greenhouse gases and odorous compounds emitted from pig slurry. Key gaseous atmospheric pollutants such as NH3, H2S, CH4, CO2 and N2O have been characterized. Furthermore, methods to reduce the emission of odours and GHGs from pig slurry during its storage and agricultural usage have been discussed.

The Possibility of Contamination of Water-Soil Environment as a Result of the Use of Pig Slurry

“…Studies by Campagnolo et al [7] showed that the concentration of chlortetracycline and sulfamethazine in water samples from field tile lines (USA) was 2000 and 300 ng/dm 3 , respectively. Hu et al [23] reported that sulfamethoxazole could be measured in groundwater samples collected from northern China, with concentration ranging from 7.2 to 9.5 ng/dm 3 .…”

“…A high demand for pork contributes to the intensification of pig production. In large-scale breeding farms mainly non-bedding system of pig farming (animals are kept on the partially or fully slatted floors) is used which generates the formation of large quantities of slurry being a heterogeneous mixture of solid and liquid animal excrement (approximately 40 % faeces and 60 % urine), uneaten feed particles and water used for hygiene and cleaning purposes in pigsty [2][3][4]. In general, pig slurry is characterized by high degree of hydration, high chemical and biochemical oxygen demand (COD and BOD) and high content of fertilizer macronutrients (nitrogen, phosphorus, potassium).…”

“…In general, pig slurry is characterized by high degree of hydration, high chemical and biochemical oxygen demand (COD and BOD) and high content of fertilizer macronutrients (nitrogen, phosphorus, potassium). Pig slurry is also rich in trace elements: iron, zinc and copper and its reaction is usually slightly alkaline [3][4][5]. The physicochemical characterization of pig slurry according to various research reports is presented in Table 1.…”

“…Bacteria of the Enterobacteriaceae family, the Streptococcus genus, coliforms and fecal streptococci are predominant. As far as pathogenic microorganisms are concerned, the bacilli of the Salmonella genus, porcine circovirus, porcine parvovirus, porcine reproductive and respiratory syndrome virus as well as eggs and oocysts of the parasites of Ascaris and Trichuris genera occur most frequently [3,4,6]. Moreover, slurry may contain antibiotics and other medical preparations which are used therapeutically and prophylactically in pig breeding [4,7].…”

Impact of Shelterbelts on Oxidation-Reduction Properties and Greenhouse Gases Emission from Soils

“…In addition, redox gradients may be used as an indicator of potential nitrification-denitrification reactions, which governs the release of nitrous oxide (N 2 O) and dinitrogen (N 2 ) from soils to the atmosphere, and the formation of carbon dioxide (CO 2 ), and methane (CH 4 ) from the degradation of organic matter. However, the proportion of these gases varies greatly with environmental conditions [5,6].…”