Search Results (2)

Replacing the linear process based on production, consumption, and disposal gives rise to the circular economy, in which materials are reincorporated into a new production process to create new amendments, following the model of sustainable agriculture. Through the circular economy approach, the aim is to add value to the waste generated during the adsorption process by recovering and reusing it as sustainable soil amendments. The present study analyzes the effects of saturated dolomitic calcareous amendment (DCAS) on the chemical properties of sandy-textured and clayey-textured agricultural soils. For this purpose, the dolomitic calcareous amendment, saturated with nutrients from hydroponic effluent through an adsorption process, was reused, and its effects on the chemical properties of agricultural soils were evaluated during incubation periods of 30, 60, and 90 days and compared with other amendments. A completely randomized experimental design was used, applying 4 treatments with 5 replications, totaling 20 experimental units for each soil type (sandy and clayey): T1 (control), T2 (dolomitic calcareous amendment in natura—DCAN), T3 (saturated dolomitic calcareous amendment—DCAS), and T4 (granulated dolomitic calcareous amendment—DCAG). The chemical properties evaluated were: pH in water, exchangeable aluminum, exchangeable calcium and magnesium, and available phosphorus. An interaction test between treatments and incubation periods was performed for each soil type and analyzed through analysis of variance, with means compared using Tukey’s test (p < 0.05) in InfoStat software, version 2020I. Through statistical analysis, it was confirmed that there was both interaction and a time effect for the variables pH, exchangeable aluminum, and available phosphorus in both sandy and clayey soils. Furthermore, the results showed that the saturated dolomitic calcareous amendment—DCAS (T3)—had good compatibility with both soil types, highlighting its ability to improve soil chemical properties by increasing pH, and available phosphorus levels, as well as completely reducing exchangeable aluminum concentration. This indicates that the saturated dolomitic calcareous amendment (DCAS) derived from the adsorption of nutrients from hydroponic effluent, can be effectively used to amend soil chemical properties, thereby promoting more efficient and environmentally sustainable agriculture. Full article

This research evaluated the recovery and reuse of dolomitic calcareous amendment saturated with nutrients adsorbed from hydroponic effluent as a soil improver and its impact on the agronomic performance of Phaseolus vulgaris. Initially, the dolomitic calcareous amendment (DCA) was saturated with nutrients from the hydroponic effluent through adsorption tests. The characterization of the DCA was conducted before and after nutrient saturation to verify its composition. Soil analysis was carried out prior to the trial, and a completely randomized experimental design was applied with four treatments and five replications, totaling 20 experimental units for each soil type (sandy and clayey): T1 (control), T2 (raw dolomitic calcareous amendment—DCA), T3 (saturated dolomitic calcareous amendment—DCAS), and T4 (granulated dolomitic calcareous amendment—DCAG). Agronomic performance parameters of Phaseolus vulgaris were assessed to determine nutrient availability to the plant: number of pods, pod length (cm), number of seeds per pod, and weight of 100 seeds (g). Data normality was verified using the Shapiro–Wilk test, and results were analyzed using ANOVA and mean comparisons through Tukey’s test (p < 0.05) using InfoStat software 2020I. Additionally, plant tissue was analyzed to determine nutrient absorption in the seeds, and both soil types were analyzed after harvest. Adsorption results indicated that the DCA retained phosphorus, manganese, calcium, and zinc. According to the characterization, DCA primarily consisted of calcium and magnesium carbonates; following the saturation process, an increase in carbonate groups was observed due to calcium adsorption from the hydroponic effluent. Results in both soil types showed no significant differences in pod number, pod length, or seeds per pod, except for the weight of 100 seeds in sandy soil, where T1, T2, and T3 differed significantly from T4. Based on references, the phosphorus content in the harvested seeds from T3 in sandy soil is classified as sufficient. The findings demonstrate the potential of recovering and reusing nutrients from hydroponic effluent using DCA and transforming it into a value-added agricultural input for soil improvement, presenting a promising alternative for more sustainable and efficient agriculture. Full article