Marek Urbaniak

This article presents the current state of biogas (biomethane) production technology—an example of the use of goat manure in terms of photofermentation efficiency. The theoretical and experimental potential of biomethane using biodegradability for anaerobic fermentation of goat manure was indicated. Goat manure was tested for its elemental composition to determine the suitability of this raw material for biogas production. The quality of biogas produced under atmospheric conditions from goat manure placed in a reactor (photodigester) was assessed. An attempt was made to determine the process conditions for immobilization on a goat manure bed (depending on the research material collected), which allows for demonstrating the activity of the fermentation bacterial flora, thus influencing the amount of biogas (biomethane) produced in the reactor. A mechanism for the photofermentation process involving the production of biomethane was developed. The novelty of this article is the development of the use of goat manure in an innovative way, pointing to the development of the biomethane industry. When comparing goat manure, active group (compact bed), it should be noted that K 3.132%, Na 0.266%, Ca 1.909% and Mg 0.993% are lower values compared to the material with values of K 3.397%, Na 0.284%, Ca 1.813% and Mg 0.990% which are higher. This is undoubtedly due to the presence of nutrients in the deposit that support the biomethane production process. The active group (compact bed) material A shows a dynamic increase in biomethane production with lower nutrient values. However, material B, having a higher percentage of ingredients, shows stabilization of biomethane production after the sixth month of the process. Technological trends and future prospects for the biomethane sector were initiated.

This paper presents the results of a study on the level of nitrate leaching from the 0–30 cm layer of grassland (GL) soil in the Lublin Voivodship during the winters of 2018/2019, 2019/2020 and 2020/2021. The amounts of leached nitrates were determined using the Burns model. For the calculations based on this model – directly and indirectly, the results determination of residual nitrate nitrogen, texture and organic matter in GL soils, obtained within the framework of agricultural monitoring of soils by the National Chemical and Agricultural Station (KSChR), and results of system meteorological measurements conducted by the Institute of Meteorology and Water Management – National Research Institute (IMGW-PIB) were used. The analysed soil samples were taken from 39 permanent control and measurement grassland sites. The research discovered in particular that: – the average leaching of nitrate nitrogen from GL mineral soil in the three analysed periods was 16.2 and 5.1 kg N∙ha–1 from organic soil; – on average, in autumn during the entire study period, 55.3% of NO3-N leached from the 0–30 cm layer of GL mineral soil, and 27.3% from organic soil; – among different agronomic categories of mineral soil, the highest leaching of NO3-N was recorded from medium soil (17.4 kg N∙ha–1) and the lowest from heavy soil (11.5 kg N∙ha–1); – individually determined values of NO3-N leaching from soil varied significantly from 0 to 68.5 kg N∙ha–1 for mineral soil and from 0.1 to 23.65 kg N∙ha–1 for organic soil.

The study analysed the relationship between the granulometric composition of grassland soils as determined by laser diffraction and their content of mineral forms of nitrogen and organic carbon. The content of mineral forms of nitrogen (NO 3-N and NH 4-N) in soil samples – after their extraction with 1% solution K 2SO 4, was determined by flow colourimetry. Soil organic carbon content was determined using the Tyurin method. The study examined soil samples collected from 169 control and measurement sites located in different regions of Poland in terms of conditions for agricultural production. Statistical analyses of the research results showed that the grain size of grassland soils had a significant effect on their ammonium nitrogen content but not on their nitrate nitrogen and organic carbon content. In this respect, it was found that there was a positive correlation between the share of the sand fraction and the content of ammonium nitrogen in soils and an opposite relation between the share of coarse silt, fine silt and clay and the content of the aforementioned component. Results of the analyses differ considerably from the results of studies by other authors on the influence of soil grain size distribution on the content of mineral nitrogen and organic carbon in soils based on classical methods of measurements of soil particle size distribution. There is a need to develop solutions to convert and compare results obtained by laser diffraction and standard methods.

The aim of the study was to assess the P-PO4 and N-NH4 pollution of water in grasslands located on peat soils and to identify the impact of groundwater level on this pollution formation. The research was conducted in 2000– 2010 on grounds of ITP-PIB in Biebrza village (Poland). Within lowland fen a total of 18 monitoring points of groundwater and watercourses were established in 6 separate test stands. The subject of the research was water collected from drainage ditches/channels and groundwater, which was taken from wells installed in organic-soil layer and wells whose bottom was 15–20 cm below this layer. Water samples were collected several times a year, and in the case of groundwater, its level was also measured. It was found that: 1) due to concentration level of P-PO4 and N-NH4, about 46 and 39% of water samples from organic-soil layer and more than 40 and 37% of water samples from mineral- organic-soil layer respectively, were characterized by poor chemical status; 2) due to the exceeding of the limit values of P-PO4 and N-NH4 concentration, water samples from watercourses in over 30 and 27% respectively were not within 1st and 2nd class of surface water quality; 3) P-PO4 and N-NH4 concentrations in each water type were statistically significant and positively correlated with each other; 4) in organic-soil layer the groundwater level changing every 10 cm was a statistically significant factor differentiating the average P-PO4 concentration in groundwater associated with mineral-organic layer of peat soil and average N-NH4 concentration in each type of water.

Background: In order to counteract the eutrophication of waterways and reservoirs, a basic risk assessment of phosphorus (P) losses in the surface runoff from agricultural land should be included in water management plans. A new method has been developed to assess the risk of P losses by estimating the degree of P saturation (DPS) based on the P concentration of the water extract water-soluble P. Methods: The risk of P losses in surface runoff from agricultural land in the Puck Commune on the Baltic Sea Coast was assessed with the DPS method. The results were compared to an agronomic interpretation of the soil test P concentration (STP). Research was conducted on mineral and organic soils from 50 and 11 separate agricultural plots with a total area of 133.82 and 37.23 ha, respectively. Phosphorus was extracted from the collected samples using distilled water on all soil samples, acid ammonium lactate on mineral soils, and an extract of 0.5 mol HCl·dm⁻³ on organic soils. The organic matter content and pH values were also determined. The results of the P content in the water extracted from the soils were converted into DPS values, which were then classified by appropriate limit intervals. Results and discussion: There was a high risk of P losses from the soil via surface runoff in 96.7% of the agricultural parcels tested (96% of plots with mineral soils and 100% of plots with organic soils). Simultaneously, a large deficiency of plant-available P was found in soils from 62% of agricultural plots. These data indicate that the assessment of P concentration in soils made on the basis of an environmental soil P test conflicts with the assessment made based on STP and create a cognitive dissonance. The risk level of P losses through surface runoff from the analyzed plots as determined by the DPS indicator is uncertain. This uncertainty is increased as the DPS index is not correlated with other significant factors in P runoff losses, such as the type of crop and area inclination.

Constructed wetlands (CWs) are becoming a popular solution for the treatment of rainwater discharged from hardened surfaces, because their construction and maintenance does not require large expenditures. The research on the effectiveness of treating runoff from the dairy farm yard was carried out using constructed wetland. The studied wetland was built in the form of two connected reservoirs with an area of 30 m(2). In the first deep reservoir, sedimentation of suspended matter occurred, while in the second shallow reservoir, six species of aquatic plants were planted in order to assimilate nitrogen and phosphorus compounds. In the years 2014-2018, the water samples from the inflow and outflow of the constructed wetland were collected. The pH and electrical conductivity values, as well as nitrate nitrogen, ammonium nitrogen, phosphates phosphorus and chlorides concentrations were determined with electrochemical and photometric methods. The obtained results were statistically analyzed using the Statistica v. 7 software. In the majority of the runoff samples from the farmyard, abnormal concentration of ammonium nitrogen (90% of samples) and phosphate phosphorus (100% of samples) occurred in relation to the requirements for surface waters. The values of ammonium nitrogen concentration exceeded the acceptable norms for domestic sewage discharged into waters in 31% of samples and in the case of phosphate phosphorus - in 67% of samples. The concentration of chlorides exceeded the limit values for surface water in 36% of samples. The average concentration of nitrate nitrogen did not exceed these standards. There was a high correlation between the concentration of ammonium nitrogen and the concentration of phosphate phosphorus and chlorides. The efficiency of runoff treatment from the dairy cattle farm yard was very high in the initial period of research, reaching 85.4% for ammonium nitrogen and 68.3% for phosphate phosphorus, but showed a downward trend over time for the entire period.

Background: Leaching of nutrients from agricultural areas is the main cause of water pollution and eutrophication of the Baltic Sea. A variety of remedial actions to reduce nitrogen and phosphorus losses from agricultural holdings and cultivated fields have been taken in the past. However, knowledge about the risk of nutrient leaching has not yet reached many farmers operating in the water catchment area of the Baltic Sea. Methods: The nutrient balance method known as “At the farm gate” involves calculating separate balances for nitrogen (N), phosphorus (P) and potassium (K). After estimating all the components of the nutrient balance, the total balance for NPK is calculated and the data obtained is expressed as the ratio of total change (surplus) to the area of arable land on a farm. In addition, the nutrient usage efficiency on a farm is also calculated. An opinion poll was conducted in 2017 on 3.6% (n = 31) of the farms located in commune of Puck. The total area of the farms including arable and grass land ranged from 5 to 130 ha with an average of 45.82 ha. The arable land was on average 30.79 ha ranging from 4.45 to 130 ha while the grassland averaged 12.77 ha and ranged from 0 to 53 ha. Results: The average consumption of mineral fertilizer in the sample population of farms was 114.9 kg N, 9.3 kg P, and 22.9 kg K·ha⁻¹of agricultural land (AL), respectively. N balance in the sample farms being ranged from −23.3 to 254.5 kg N·ha⁻¹AL while nutrient use efficiency ranged from 0.40% to 231.3%. In comparison, P surplus in the sample farms was 5.0 kg P·ha⁻¹AL with the P use efficiency of 0.4–266.5%. Discussion: Mean N fertilizer consumption in the tested farms was higher than the average usage across Poland and in the Pomeranian Voivodeship. However, mean consumption of potassium fertilizers was lower than mentioned averages. Mean P fertilizer consumption was higher than in the Pomeranian Voivodeship, but lower compared to the entire country. Generally, on the basis of designated research indicators of farm pressures on water quality, concentrations of total nitrogen and total phosphorus were obtained. CalcGosPuck (an integrated agriculture calculator) will help to raise farmers’ awareness about NPK flow on farm scale and to improve nutrient management.

The changes in dissolved organic carbon (DOC), N-NO