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One way to manage sewage sludge, which is consistent with the assumptions of the European Green Deal, is to use it in agriculture. The study focused on the possibility of using soil enzyme activity and the GMea index (the geometric mean of enzyme activities) in connection with the total organic carbon (TOC) and the total nitrogen (TN) content to assess the quality of fallow light soil after exogenous organic matter (EOM) fertilization. Exogenous organic matter in the form of stabilized municipal sewage sludge was introduced into the soil. The experiment included five variants: one control site and four sites with 30, 75, 150, and 300 Mg ha−1 of sewage sludge added to the soil. The contents of TOC, TN and heavy metals (Zn, Cu, Pb, Cd) in the soil material were assayed. In addition, the activity of soil enzymes, i.e., neutral phosphatase, urease, protease and dehydrogenase, was examined, and the geometric mean of the enzyme activities (GMea index) was calculated. Fertilization of light soil with sewage sludge resulted in an increase in TOC and TN proportionally to the EOM dose. The addition of sewage sludge increased the content of tested heavy metals in the soil and did not exceed the levels considered acceptable. The introduction of sewage sludge contributed to the stimulation of biological life in the soil. This was evidenced by an intensification of soil enzyme activity. However, individual enzymes showed a different response to EOM fertilization, while GMea showed a significant increase in the quality of the fallowed soils as the EOM rate increased to 150 Mg ha−1.

Soil plays a key role in sustainable land management and food production. The objective of the field experiment was to evaluate the subsequent effect of 10-year winter wheat and sugar beet cultivation under conventional and organic systems on selected physicochemical and biochemical properties and enzymatic pH index of lessive soil developed from loess under climatic conditions of Southeastern Poland. The experiment was set up by using the split-plot design, with three replications, on plots of 30 m2. In order to evaluate the soil value of sites cultivated in 2010–2019 in two systems—conventional agriculture and organic agriculture—spring wheat was sown as a test crop in 2020. Fertilization and pesticide applications (herbicides, fungicides and insecticides) were foregone in the cultivation of this crop due to the desire to capture the subsequent impact of 2010–2019. This resulted in soil properties shaped solely by the previous 10 years of cultivation. The obtained results indicate that the organic farming system contributed to the improvement of soil pHKCl compared to the conventional system, with statistically significant differences recorded only for winter wheat cultivation. Compared to the conventional system, in the organic farming system, improvements were recorded in the chemical indicators of loess soil quality (TOC, TN and TOC/TN) and P content, as well as acid phosphatase and alkaline phosphatase activities. However, statistically significant differences were found only for winter wheat cultivation. Research on the impact of an organic system of growing different species in rotation should be continued, and the results should be implemented.

Recent years have brought dynamic developments in surveying equipment and techniques. These include reflectorless electromagnetic distance measurement (RL EDM), which is used in a range of devices, especially total stations. Studies concerning the influence of the reflecting surface on the accuracy of RL EDM tend to focus on the colour of the measurement surface, while the influence of the density and thickness of materials is usually neglected. Therefore, this study undertook to examine 53 samples representing various materials of dissimilar features: colour, type of surface and density. The results show that dark and mat surfaces cause higher RL EDM errors than bright, gloss materials. Nonetheless, 76% of the results were in compliance with equipment specifications. Moreover, it was found that the density of the samples had significant impact on the overall accuracy. RL EDM to EPS (expanded polystyrene sheets, low-density material, commonly called Styrofoam) involved a significantly higher error rate. It demonstrates that total station measurements and laser scanning should be performed cautiously, especially with regard to materials of low density (e.g., EPS) and on short distances, where the value of relative error is high.