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| Author(s): |
Ramom Rachide Nunes
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Carlos. |
| Institution: | Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC/BT) |
| Defense date: | 2017-03-06 |
| Examining board members: |
Maria Olimpia de Oliveira Rezende;
Pedro Sérgio Fadini;
Maria de Lourdes Leite de Moraes;
Perola de Castro Vasconcellos
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| Advisor: | Maria Olimpia de Oliveira Rezende |
| Abstract | |
The industrial activity for leather production generates a high amount of potential polluting wastes, usually rich in chromium, a toxic element with risks to the environment and human health. In general, the wastes produced during the production of leather -- finishing tannery -- mainly comprises a mixture of tanned chips of leather wet-blue and also the sludge from the plant of effluent treatment. An alternative to the environmental problem involving these residues would be to convert them into noble organic compounds, and for that purpose the vermicomposting was suggested as a viable alternative technology. Vermicomposting is an advanced biological process which emphasizes the detritivore action of the earthworms and microorganisms present in their digestive tract, leading to the production of agricultural inputs -- vermicompost -- with high agronomic quality and nutritional potential for the plants and agricultural crops. In addition, these vermicomposts could be applied to organic, family farming or any ecologically based agricultural activities. Thus, the present study aimed to apply the vermicomposting in the treatment and reutilization of tannery waste for the preparation of inputs for organic farming, in addition to conducting a chemical, spectroscopic, and hormone-biostimulating study of the processes involved, furthermore to applying these inputs in the organic cultivation of Capsicum annuum L. For this, the studies were divided in three chapters, (1) vermicomposting applied to the valorization of the organic matter of the tannery residues and the preparation of the agricultural inputs; (2) investigation of organic molecules determined in the vermicomposted DOM and HAs with any biostimulating role regarding to the hormone-like effect and auxin-like action under germination tests with Lactuca sativa seeds; and (3) application of the vermicomposts in the organic cultivation of sweet pepper in greenhouse. In addition, the Cr dynamics, since the vermicomposting until its transport from the substrate to the plant, was investigated. According to the results obtained in the vermicompost monitoring, the variations in the values of the analyzed attributes (pH, TOC, OM, C:N ratio, etc.) indicated that the vermicomposts reached the stability and the desired maturity. For the Cr, at the end of the vermicomposting, all values of Cr (VI) were below the detectable level, indicating the Cr (VI) bioconversion into Cr (III). Regarding the hormone-like activity, both extracts of HAs and DOM showed an auxin-like effect, but this effect was more intense in HAs, which completely inhibited the germination of L. sativa seeds at higher concentrations. In addition, samples with higher concentrations of amino acids and carboxylic acids with aliphatic and aromatic chains were the most bioactive. Data related to vermicompost application indicated that it is possible to cultivate organic sweet pepper using this agricultural input, obtaining a production up to 3 fruits plant-1, as well as healthy and well-developed plants. When investigated the Cr dynamics in the plants (egg, root, stem, leaves), its highest concentration was determined in the fruits, but below the value recommended by the USDA for daily human ingesting (25.0-35.0 μg Cr day-1). Consequently, the harvested sweet peppers are suitable for human consumption and do not present risks to food security and human health. In general, these findings reinforce the idea that the vermicomposting can be introduced as an effective technology in the treatment of the tannery waste and the production of agricultural inputs. In addition, we concluded that the vermicomposts -- produced along the tannery residues -- can be applied in the organic cultivation of sweet pepper in greenhouse, resulting in a good productivity rate and potentially marketable produce, due to the appearance and quality of the obtained sweet peppers. (AU) | |
| FAPESP's process: | 13/00744-0 - CHEMICAL AND SPECTROSCOPIC STUDY OF VERMICOMPOSTING DYNAMICS OF WASTE FROM LEATHER INDUSTRY (TANNERY) FOR PRODUCTION OF PLANTS WITH ECONOMIC INTEREST |
| Grantee: | Ramom Rachide Nunes |
| Support Opportunities: | Scholarships in Brazil - Doctorate |