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Controlled-release urea (CRU) fertilizer application has been shown to improve crop yield and nitrogen (N) use efficiency. However, its effects when mixed with conventional urea fertilizer on soil aggregate stability, humic acid (HA) molecular composition and crop N uptake remain unclear. Soil and plant samples were collected from a long-term (2008-2019) experiment on field maize (Zea mays L., ‘Zhengdan 958’) which included two types of fertilizers [conventional urea fertilizer (CUF), blended CUF with CRU fertilizer (CRF)], four N application rates (0, 150, 300 and 450 kg ha-1), each in three replicates. The results showed that at 300 kg N ha-1, compared to CUF treatment, the CRF treatment significantly improved soil aggregate characteristics [aggregate content with particle size larger than 0.25 mm (R0.25) by 9.6%, mean weight diameter by 19.8%, and geometric mean diameter by 21.7%]. CRF treatment also increased HA content by 5.5%, fulvic acid (FA) by 5.5%, lignin-like molecules by 0.94 times, and protein-like molecules by 3.69 times. At grain-filling stage, CRF treatments significantly increased the sum of soil NH4+-N and NO3–N content by 23.3-24.5%, sap bleeding rate by 12.8-18.2% and N delivery rate through bleeding sap by 60.6-87.7% compared to CUF treatments at the same N application rate. At the same rate of N application, the CRF treatments significantly improved the average yield during three growing seasons by 9.4-14.0% in contrast with CUF treatments. The regression equations showed that the maximum yield was 8294 kg ha-1 for CUF at the application rate of 312 kg N ha-1 while it was 9890 kg ha-1 for CRF at the application rate of 286 kg N ha-1. We conclude that the long-term application of CRF changed the HA molecular structure, enhanced the water stable aggregates, improved crop N uptake, and increased economically viable maize yield.While pesticides are generally recognized as contributing to amphibian declines, there is a lack of knowledge about effects of co-formulants that are present in pesticide formulations and adjuvants which are mixed with these formulations. Since aquatic and terrestrial stages of amphibians can be exposed to these substances, adverse effects cannot be excluded. We investigated acute aquatic and terrestrial effects of the herbicide formulation Focus® Ultra, its active substance cycloxydim, its co-formulants solvent naphtha and docusate as well as the stabilizing adjuvant Dash® E.C. on larval and juvenile Rana temporaria. Aquatic toxicity was determined as 96-h LC50 values. Cycloxydim was the least toxic and solvent naphtha the most toxic substance of the formulation. The addition of Dash® E.C. increased the formulation toxicity substantially. Terrestrial toxicity was determined as lethal effects after a 48-h exposure to contaminated soil with 100% of the recommended field rate (FR) and as sublethal effects after the exposure to 10% of the recommended FR. The exposure to solvent naphtha and docusate at 100% FR led to mortalities of 42-100% probably due to their inhalation toxicity and dermal as well as eye irritation, respectively. Cycloxydim, Focus® Ultra and Dash® E.C. did not lead to any mortality. Sublethal effects on juvenile locomotor activity (i.e. moved distance) were observed for cycloxydim and the combined exposure of Focus® Ultra and Dash® E.C. Juvenile body masses declined significantly for all substances except for cycloxydim. The present results show that aquatic sensitivity does not predict terrestrial sensitivity. It was shown that pesticide toxicity for amphibians can highly depend on the presence and amount of co-formulants and added adjuvants. Therefore, substances included in pesticide formulations which are known to be toxic by inhalation or harmful to eyes or skin should be specifically considered in the environmental risk assessment for amphibians.Soil microbial communities act on important environmental processes, being sensitive to the application of wastes, mainly those potential contaminants, such as tannery sludge. Due to the microbiome complexity, graph-theoretical approaches have been applied to represent model microbial communities interactions and identify important taxa, mainly in contaminated soils. Herein, we performed network and statistical analyses into microbial 16S rRNA gene sequencing data from soil samples with the application of different levels of composted tannery sludge (CTS) to assess the most connected nodes and the nodes that act as bridges to identify key microbes within each community. The network analysis revealed hubs belonging to Proteobacteria in soil with lower CTS rates, while active degraders of recalcitrant and pollutant chemical hubs belonging to Proteobacteria and Actinobacteria were found in soils under the highest CTS rates. The majority of classified connectors belonged to Actinobacteria, but similarly to hubs taxa, they shifted from metabolic functional profile to taxa with abilities to degrade toxic compounds, revealing a soil perturbation with the CTS application on community organization, which also impacted the community modularity. CX-5461 mw Members of Actinobacteria and Acidobacteria were identified as both hub and connector suggesting their role as keystone groups. Thus, these results offered us interesting insights about crucial taxa, their response to environmental alterations, and possible implications for the ecosystem.In Antarctica, waste is generated mainly during scientific research programmes and related logistics. In this study, the impact of wastewater on the western shore of Admiralty Bay was investigated during austral summer in 2017 and 2019. A range of physicochemical parameters and the presence of selected trace metals, formaldehyde and different groups of surfactants were determined in wastewater coming from Arctowski Station and in nearby coastal waters. The presence of selected trace metals (e.g., Cr 2.7-4.4 μg/L; Zn 15.2-37.3 μg/L; and Ni 0.9-23.3 μg/L) and the sums of cationic (0.3-1.5 mg/L), anionic (3.1-1.7 mg/L), and non-ionic (0.6-2.4 mg/L) surfactants in wastewater indicated the potential influence of anthropogenic factors on sea water. The determined surfactants are found in many hygiene products that end up in the waste water tank after human use and, if untreated, can be released into surface waters with discharge. In addition, the levels of some trace metals indicate that they cannot come only from natural sources, but are the result of human activity.