Estudio de la acumulación de plomo y cadmio por Asphodelus fistulosus L. y Brassica juncea L. para fitorremediar jales
Soil contamination with heavy metals such as lead, cadmium, nickel, chromium and zinc, are attributed to various human activities such as irrigation with wastewater, improper disposal of effluents, the mining and smelting industry, including some others. Thus the use of plants as decontaminating age...
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| Tipo de documento: | dissertação |
| Estado: | Versão publicada |
| Data de publicação: | 2009 |
| País: | México |
| Recursos: | Universidad Autónoma Metropolitana |
| Repositório: | Repositorio Institucional de la UAM Iztapalapa |
| Idioma: | espanhol |
| OAI Identifier: | oai:bindani.izt.uam.mx:9593tv344 |
| Acesso em linha: | https://doi.org/10.24275/uami.9593tv344 |
| Access Level: | Acceso aberto |
| Palavra-chave: | info:eu-repo/classification/LEM/Soil Pollution -- Mexico info:eu-repo/classification/LEM/Lead info:eu-repo/classification/LEM/Plomo info:eu-repo/classification/LEM/Cadmium info:eu-repo/classification/LEM/Mineral Industries -- Mexico info:eu-repo/classification/LEM/Contaminación de suelos -- México info:eu-repo/classification/LEM/Industria minera -- México info:eu-repo/classification/LEM/Cadmio info:eu-repo/classification/cti/6 |
| Resumo: | Soil contamination with heavy metals such as lead, cadmium, nickel, chromium and zinc, are attributed to various human activities such as irrigation with wastewater, improper disposal of effluents, the mining and smelting industry, including some others. Thus the use of plants as decontaminating agents represents an important economic alternative technology. The objective was to study the accumulation and/or stabilization of lead and cadmium by Brassica juncea and Asphodelus fistulosus, for utterly use in phytoremediation of tailings from Tlaquiltenango, Morelos. To carry out with the objective, physicochemical characterization of tailings (pH, moisture, texture, field capacity, cation exchange capacity and void space) and the sequential extraction of lead and cadmium available were evaluated. Germination of both species was carried out under in vitro cultures, where growth and healthy development were observed for over a month. Subsequently, plants were transplanted onto a medium containing perlite-peat moss (1:1 w/w). After 30 days the plants were transplanted to 1 kg new pots containing different proportions of tailings to obtain the following initial Pb concentrations: 1 200, 2 500, 5 000, 6 200 and 7 100 mg Pb kg-1 for next 60 days. All experiments were performed under controlled conditions of light and temperature. Subsequently, lead and cadmium were quantified by atomic absorption spectroscopy (AAS); in shoots, B. juncea accumulated up to 1 698 mg Pb/kg dry weight in shoots and 153 mg Cd/kg dry weight in shoot. For this reason B. juncea can be considered a hyperaccumulator species of both metals. On the other hand, A. fistulosus accumulated up to 1 432 mg Pb/kg dry weight in roots and 850 mg Pb/kg dry weight in shoots. Furthermore accumulated 112 mg Cd/kg plant dry weight in shoots, for this reason it can be considered as a Pb excluder and Cd hyperaccumulator. In addition histochemical studies confirmed the quantitative metals content in the roots and shoots; the deposition of lead in histological sections of shoots from B. juncea were mainly observed in the stomata, vascular system, parenchyma, epidermis and apoplastic spaces. Deposits of lead in the root of A. fistulosus were observed in the cortex, whereas in the leaves was not observed lead. The main proposal that emerges from this work is that by cultivating A. fistulosus may reduce the risk of wind dispersal of heavy metals, particularly lead which is present in the tailings. Key words: phytoremediation, mine tailings, heavy metals |
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