Filters
Assessment of the Influence of Aluminum, Iron, and Manganese Forms on the Phytocenoses of Post-Mining Lands in the Lengerskoye Brown Coal Mine
Post-mining land in areas where mineral extraction has occurred may constitute a significant portion of the land used for various purposes. Such land serves as soil-forming parent material for developing anthropogenic soils, which sometimes exhibit unfavorable physicochemical properties. The toxicity of the waste generated during lignite mining is due to a number of factors, whose determination permits the identification of its origin for the subsequent design of technologies for the waste reclamation. The purpose of the study, in consistence with sustainable development, is to identify the causes of the toxicity of brown coal waste from the Lengerskoye deposit, in southern Kazakhstan. These studies have provided the results essential for planning remedial actions necessary to improve the well-being of the local population, in accordance with the principles of sustainable development. The studies were performed using single extraction; forms of Al, Fe, and Mn; soil texture; elemental analysis; phytocoenosis analysis; and diffractometric, IR spectroscopic, SEM, route reconnaissance, and comparative statistical methods. A decrease in the biodiversity of plant species was noted, with a gradual increase with distance from the waste storage sites. The most resistant plant species in the vicinity of the waste dump were Cynodon dactylon (L.) Pers and Alhagi pseudalhagi (M. Bieb.) Desv. ex B. Keller & Shap., while Dodartia orientalis (L.) was the only plant species found at the edge of the waste dump. The high toxicity of lignite waste is determined by such factors as low pH values, about 3.0; high content of active forms of aluminum, iron, and manganese (344.0, 0.90, and 20 mg/kg); high electrical conductivity—2835 µS/cm; waste composition poor in nutrients; and climate aridity. It has been observed that a content of exchangeable aluminum above 100 mg/kg resulted in an almost complete lack of vegetation.
Financial Security as a Basis for the Sustainable Development of Small and Medium-Sized Renewable Energy Companies—A Polish Perspective
In conditions of economic and political instability, when unpredictability affects business, the need for security, including financial security, becomes particularly important. In our study, we address this issue, with the main objective of comparing and evaluating the financial security of small and medium-sized renewable energy companies in Poland according to sustainable development goals. In order to study and describe relationships between selected groups of companies, financial ratios were used, including canonical variate analysis. The liquidity ratios of the surveyed companies indicated a low level of financial security in terms of the ability to meet short-term liabilities. The profitability of operations was low and did not contribute to the improvement of financial security in most of the companies. The lowest return on assets was found in the group of biogas plants. Higher profitability of assets was found in solar power plants, including those with system installations. Solar power plants were also characterized by a high level of total debt and a rapid turnover of assets in comparison to other studied companies. The results show that the financial security of small and medium-sized renewable energy enterprises in Poland is low, which may be a threat to sustainable development in the future.
The Influence of some Climatic Conditions on the Yield and Fruit Quality of Replanted Apple Orchard
A Case Study on the Effect of Foliar Nitrogen Fertilization on the Microbiological and Biochemical State of the Soil and the Uptake of Macro- and Microelements by Winter Triticale (Triticosecale)
Due to the increasing demand for food, the agricultural sector is facing a huge challenge related to its production without having a negative impact on the environment. The above issues are regulated by the current EU policy, indicating the need to conduct plant production by the European Green Deal strategy (2020), based on reducing the use of chemical plant-protection products by 50% and reducing the level of mineral fertilization by 20% by 2030. Using appropriate techniques of applying mineral fertilizers, which have a positive effect on the development and activity of soil microorganisms, the availability of nutrients in the soil can be increased while reducing fertilizer applications. This study aims to show whether the use of foliar nitrogen fertilizers in combination with sulfur in a two-year field experiment with triticale stimulates the multiplication of selected groups of microorganisms and the level of soil enzymatic activity. In addition, effects on the content of available forms of nutrients in the soil, triticale yield, and total nutrient uptake were analyzed. It is shown that the applied foliar fertilizers enriched with sulfur, compared to fertilization with ammonium nitrate, contributed to a 100% increase in the number of analyzed groups of microorganisms, urease, and alkaline phosphatase activity; a 44% increase in dehydrogenase activity; and a 15% increase in acid phosphatase activity. The hybrid application technique, with reduced doses of nitrogen fertilizers enriched with sulfur by 20 and 25%, resulted in grain yields exceeding 8 t/ha. Moreover, compared to conventional fertilization based on ammonium nitrate, an increase in the grain yield of triticale was obtained in the range of 16 to 24%, as well as an increase in the accumulation of nutrients in the plant. It is shown that foliar fertilization is a promising alternative to standard fertilization techniques.
Functioning of the Energy Sector Under Crisis Conditions—A Polish Perspective
In the context of the coronavirus pandemic and the armed conflict between Russia and Ukraine, energy security is essential to economic challenges nowadays. The basis for the proper operating of the energy sector is to ensure a stable supply of energy to end users and to secure finances of energy companies, so that they can operate sustainably in times of uncertainty. In our studies, we have addressed this issue with the main objective of assessing the state of energy security from the perspective of the stability of the financial situation of energy sector companies in the context of the global energy crisis and a sustainable energy future. Financial indicators and a canonical variable analysis were used to examine the financial situation of companies in the energy sector and to describe links between selected groups of energy companies. Such companies operating during political and economic instability did not record worse financial results than in the year 2018. It was found that in case-studied firms, total debt decreased and moreover, liquidity and return on assets improved. Companies have focused on securing their financial health and ensuring the stability of their energy supplies and the issue of the environmental impact of energy production has unfortunately become a secondary concern. Nevertheless, in the event of further crises, it is reasonable to assume that a focus on maintaining liquidity and generating profits for energy companies will be more important to companies than environmental challenges and the fight against climate change.