Agricultural production is influenced by the water content in the soil and the availability of nutrients. Recently, changes in the quantity and seasonal water availability are expected to impact agriculture due to climate change. This study aimed to test an agricultural product with promising properties to improve soil quality and water-holding capacity during agricultural application. Most of the traditional hydrogels are low-biodegradable synthetic materials with under-researched long-term fate in field soil conditions. The novel, biodegradable hydrogel made from acid whey and cellulose derivatives cross-linked with citric acid was used. The soil-improving effects were tested under controlled experimental conditions with the sandy artificial soil consisting of 10% finely ground sphagnum peat, 20% kaolinite clay, and 70% quartz sand. Soil pH, the content of organic carbon (Cox), total nitrogen (N), available forms of the essential macronutrients (P, K, Ca, and Mg), the cation exchange capacity (CEC), the maximum water capacity (MWC) and water holding capacity (WHC) were determined. The results showed a positive effect on water retention and basic soil properties after the different levels of hydrogel had been introduced into the soil. Generally, the addition of whey-based hydrogel increases the available nutrients concentration and water retention in soil.

Abandoned agricultural objects from the period of large-scale agricultural production in the socialist era represent a peculiar topic in the former communist countries of Eastern Europe, surpassing the experience of the EU15 countries or USA that have extensive and long-standing practice in brownfields redevelopment. The question of brownfields resulting from the transformation of the agricultural sector during the transition period of the Czech Republic is presented in this paper. Agricultural brownfields are the most frequently occurring brownfields in the Czech Republic (especially in some regions), but their area share is much lower, indicating their spatial disposition in the landscape. Some aspects of agricultural brownfields regeneration, including possibilities of its funding, are discussed in the paper. We also deal with geographical, environmental and historical aspects of the existence of these localities in the Czech Republic in the context of potential financial resources and possibilities for funding their revitalization.

Agriculture and related crop production are highly dependent on climate and economic factors, and agricultural intensification is associated with a dramatic increase in the consumption of fertilizers. A significant amount of the elements from the most commonly used fertilizers is degraded and lost due to climatic and environmental factors. The soil application of novel whey-based hydrogel represents an innovative approach toward efficient fertilizing and soil water balance that resonates with the concepts of sustainable agriculture and circular economy of waste products. Results of previous research show the positive effect of whey-based hydrogel on water retention after the various levels of hydrogel have been applied into artificial soil. With a view to verifying the effect of the whey hydrogel on soil quality and related crop cultivation in real conditions, the pot experiment compared two different doses of whey hydrogel with control soil, with the conventional NPK treatment of soil and with a mixing strategy combining the conventional NPK treatment with hydrogel application. The controlled pot experiment was conducted with haplic Cambisol, with white mustard (Leucosinapis alba) and spring barley (Hordeum vulgare) as the testing crops. Soil pH, organic carbon (C), total nitrogen (N), available forms of the essential macronutrients (P, K, Ca, and Mg), and the cation exchange capacity (CEC) were determined in Cambisol samples before and after the experiment. The crop yields of barley and mustard were compared among the various treatments of experimental soils. Results demonstrated that the amendment of whey-based hydrogel increased the bioavailable nutrients’ concentrations, which persisted even after the harvest. The nutritional quick boost after the whey-based (co)-application significantly increased the experimental crop yield.

The paired Fluvisol and cereal samples in both the field screening and controlled experiments are reported to elucidate the soil–crop relationship for As, Cd, and Pb in relation to changing contamination levels. Significant varietal differences in plant uptake were observed for crop type (barley, triticale) and the harvested part of the crop (oat shoots and grain). When parametrizing the stepwise regression models, the inclusion of soil properties often improved the performance of soil–crop models but diverse critical soil parameters were retained in the model for individual metal(loid)s. The pH value was often a statistically significant variable for Cd uptake. For As and Pb, the more successful model fit was achieved using the indicators of quantity or quality of soil organic matter, but always with lower inherent model reliability compared to Cd. Further, a single correlation analysis was used to investigate the relationship between extractable metal concentrations in soil solution and their crop accumulation. For Cd, there were strong intercorrelations among single extractions, the NH₄NO₃ extraction stood out with perfect correlation with plant uptake in both experiments. For As and Pb, the CaCl₂ and Na₂EDTA solutions outperformed other single extractions and were the better choice for the assessment of depositional fluvial substrates.