Technical Analysis in Trading Securities.

katedra inženýrské informatik

The Effect of Ash Admixture on Compost Quality and Availability of Nutrients

The effect of graded doses of ash from biomass wood chips and straw admixture combustion on compost properties was investigated through a set of large-scale experiments. In a compost plant, matured organic composts were prepared from raw organic mixtures based on biodegradable waste, separated digestate, straw, and biomass ash admixture of 0, 3, 6, and 9 wt. %. Final composts, as well as individual components, were analyzed for basic physical and chemical properties, total and available nutrients, and potentially hazardous elements. Biomass ash addition increased the total nutrient content (P, K, Mg, Ca, and S) in the studied composts. The highest ash addition (9 wt. %) increased the nutrient content as follows: Ca (2.6×), Mg (1.6×), K (1.5×), P (1.2×), S (1.3×). However, the availability of some nutrients (especially P, K, and Mg) for plant nutrition was reduced by the increasing amount of ash admixture. Even at the highest dosage of biomass ash addition, desirable chemical (nutrient content) and physical properties of composts (especially dry bulk density) were both obtained. The content of hazardous elements was below the legal limit values in all studied composts

The Balance of the Nitrogen in Agriculture

Methodology addressing nitrogen balance issues is a suitable tool for verifying the correctness of agricultural management and shows the relation between nitrogen used in agriculture and its losses in gaseous form to air or in the form of nitrates to surface and groundwater. The assessment of nitrogen balance, greenhouse gas emissions and pollutants is closely linked and therefore requires the quantification of nitrogen sources used in agriculture. Synchronization of input data used to evaluate nitrogen flows in agriculture is essential to increasing the methodological level of reporting the nitrogen balance, greenhouse gas emissions and pollutants for the Czech Republic in terms of the requirements of international organizations

Digestate Application Methods and Rates with Regard to Greenhouse Gas Emissions and Crop Conditions

Digestate is commonly used as a liquid organic fertilizer, as it contains nutrients that are important for plant growth and thus help reduce usage of mineral fertilizers. Since the digestate application leads to the release of greenhouse gases (GHGs) into the atmosphere, it is necessary to find a suitable application method and fertilizer rate with minimal gas emissions while providing sufficient nutrients to crops. The aim of this study was to investigate the relationship between selected GHGs and ammonia (NH3) release into the atmosphere and different rates of digestate applied, i.e., 0, 10, 20, 30, and 40 m3 ha−1. Two digestate incorporation methods were used, i.e., a disc application unit (D) and strip-till (S). The fluxes, i.e., methane (CH4), ammonia, and carbon dioxide (CO2), were monitored using the wind tunnel method. Crop growth and potential nutrient utilization by silage maize were assessed through stand condition monitoring by the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) using remote sensing. Under the given conditions, the digestate rates and the compared application methods had significant effects on the level of fluxes. The rate of digestate was confirmed to affect the yield of silage maize. The yield increased by more than 8% when using the disc applicator. Based on our results, it is advisable to apply digestate by strip-till technology at rates of approximately 20 m3 ha−1

Effects of Temperature and Pressure on Hemp Oil Filtration Parameters and Peroxide Number

This article focuses on the quality of hemp oil processing, specifically the filtration that is an important part of the technological procedure of processing vegetable oils. The aim of the research was to determine the effects of pressure and temperature on the filtration parameters when using plate filters. The research was carried out on an experimental measuring device with adjustable static pressure. The qualitative properties of the oil were observed in terms of analytical composition, microbial content, and changes in peroxide value as the indicator of oxidation stability. The change in pressure affected the oil flow rate, especially at lower pressure values. The increase in temperature of the filtered oil had a negative impact on the oxidation stability