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A high pH, low solubility of bound plant nutrients, and negative impacts on microbial communities are common drawbacks of biomass ash (BA) vermicomposting. In this study, nutrient-rich BA mixed with cow manure was tested at three different application rates to obtain final nitrogen (N), phosphorus (P), and potassium (K) contents of 3.5%, 7.0%, and 10.0% for bio-based fertilizers via vermicomposting. The results showed that all BA blends made with cow manure increased fermentation temperatures and allowed successful worm activity during the subsequent vermicomposting phase. The order of indicator enzyme activities in all vermicomposting samples was urease (220 μg NH4 g−1 h−1) > β-glucosidase (95 μg PNP g−1 h−1) > alkaline phosphatase (91 μg PNP g−1 h−1) > arylsulfatase (83 μg PNP g−1 h−1) > acid phosphatase (60 μg PNP g−1 h−1). As an indicator of nutrient bioavailability, high correlations were observed between enzyme activities and microbial diversity in vermicompost samples. Determination coefficients (R2) obtained from multiple linear regressions between enzyme activities and bacterial population for T0, T1, T2, and T3 were determined as 0.90, 0.65, 0.73, and 0.90, respectively. According to a novel metagenome-based approach proposed within the scope of the present study, the stimulatory effects of Flavobacteriales, Burkholderiales, Saccharimonadales, and Pseudomonadales on enzyme activities for the nutrient solubility were found to be significant and positive. The findings of this study demonstrated that worm composting could be a sustainable bio-based technology for the production of slow-release fertilizer from nutrient-rich waste material. [ABSTRACT FROM AUTHOR]

The dye removal efficiency of the green algae Ulva lactuca from textile wastewater was assessed in a batch experiment series by evaluating the initial dye concentration, contact time, pH, biosorbent quantity, and temperature. In addition, the structural characterization of Ulva lactuca for adsorption was determined using an FT-IR spectrum, SEM image, and BET analysis. After this process, methylene blue was used as a model compound for the adsorption of organic pollutants from aqueous solutions. The compatibility of isotherm models, as well as the isotherm constants and correlation values for the adsorption balance system, were determined using the experimental data. The optimum adsorption was found at around pH 7, in 10 minutes of contact time through biosorbent dose of 0.5 g/L and initial dye concentration of 5 mg/L. Within this context, biosorption value at optimum values was 0.322 mg/g. At optimum conditions, the estimated maximum removal percentage value was 89%. Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherm models respec-tively had determination coefficients of 0.999, 0.983, 0.988, and 0.930. The Langmuir isotherm model was rather found to be more compatible with experimental protocols. As a result of the studies for adsorption kinetics, the determination coefficient of the pseudo-second-order kinetic models was calculated as 1.000. According to thermodynamic experiments which were interpreted as an exothermic event, the adsorption event occurred non-spontaneously. [ABSTRACT FROM AUTHOR]