Digestate application with regard to greenhouse gases and physical soil properties

P. Šařec¹, J. Korba¹*, V. Novák¹ and K. Křížová¹²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Machinery Utilization, Kamýcká 129, CZ165 00 Prague 6, Czech Republic
²Crop Research Institute, Division of Crop Protection and Plant Health, Drnovská 507/73, CZ161 06 Prague, Czech Republic
*Correspondence: korba@tf.czu.cz

Abstract:

The article deals with the method of application of digestate with regard to the environment, soil properties and utilization of nutrients by plants. The aim is to monitor the dependence of the emission gas leakage and the dose of applied fertilizer. With the current expansion of biogas plants, a large amount of waste product, especially digestate, is being generated. This product is most often used as a liquid organic fertilizer because it contains substances important for plant growth. The disadvantage of this fertilizer is the release of greenhouse gases into the air. The digestate contains mainly ammonia, nitrogen in the residual organic matter and is a fertilizer with rapidly releasing nitrogen. The ammonium nitrogen contained in the digestate is easily subject to air losses. Therefore, a method of application for a certain crop is sought, where the smallest leaks of gases into the air occur. Different amounts of doses for the same route of administration are compared. To measure the amount of emission gases, a wind tunnel was placed on each variant of the application, taking air above the soil surface, which is discharged to the gas analyser. The monitored greenhouse gases are CH₄, NH₃ and CO₂. Furthermore, physical properties of soil were monitored in order to verify the conditions of the experiment. One of the parameters measured was the soil bulk density of the soil by taking intact soil samples. The penetration resistance of the soil was also determined, which indicates the degree of compaction. The use of nutrients was assessed through the condition of the stand on each variant by monitoring vegetation indices using remote sensing of the earth.

Key words:

Assessment of the methane emission for different typologies of fattening swine facilities in the department of Antioquia – Colombia

N. Castrillón²³*, V. González¹³, J.A. Osorio¹, A.P. Montoya¹ and G. Correa¹

¹Universidad Nacional de Colombia, sede Medellín, Facultad de Ciencias Agrarias, Carrera 65 #59A-110, Código postal CO050034 Medellín, Colombia
²Universidad Nacional de Colombia, sede Medellín, Facultad de Minas, AV 80 #65-223, Código postal CO050034 Medellín, Colombia
³Grupo de Investigación en Biodiversidad y Genética Molecular (BIOGEM), Departamento de Producción Animal, Universidad Nacional de Colombia, Sede Medellín, Carrera 65 No. 59 A-110, CO050034 Código, Colombia
*Correspondence: ncastrillon@unal.edu.co

Abstract:

The explosive growth of swine production at high stocking densities in confinement farming worldwide, has raised concerns the environmental impact, health and livestock productivity and the production of associated gases in this type of large-scale farms. The aim of this paper was to study the methane gas concentration and emissions of ten different typologies of swine production installations. The facilities were in the department of Antioquia – Colombia, they were located between 800–2,300 meters above sea level (m.a.s.l.) of heights, they mainly employed natural ventilation as refrigeration strategy and they were used for pigs in fattening stage. Methane measurements were taken at animal height. Sensors were located at intermediate points of the ventilation inlet and outlet areas. The behaviour of methane concentration and emission of the facilities were analysed along with the correlation and temporal evolution of climatic variables, comfort indices and construction typologies. The information was analysed using descriptive statistics, analysis of variance (ANOVA) and principal component analysis (PCA). Were found an average of CH₄ Emission Rate (ER) per facility (kg year^-1) of 607.9, Global Warming Potential (GWP) per facility (kg year^-1) of 15,197.42 and significant correlations between ER and cleaning frequency (CF), animal unit (AU), air flow (Q), animal density (AD) and relative humidity (RH) were evidenced. This is the first research reported in Colombia, that will be important to create some governmental policies.

Key words:

greenhouse gases, methane emissions, natural ventilation, swine production, typologies of construction