Plants in mining areas can cure soil affected by contamination in very short timeMarch 12, 2010When conditions become complicated, there is no choice but to adapt to them. Plants have to do the same. Some of them growing in mining areas have unusual strengths, accustomed as they are to living in a toxic environment and knowing how to deal with this. Based on this capacity to adapt, researcher Ms Lur Epelde used these plants as medicinal herbs for contaminated soils. The current level of contamination in the soil, caused by human intervention - is highly worrying. Nevertheless, more than the contamination as such, Ms Epelde was more interested in the effect these plants have on the health of the soil. The researcher puts forward phytoremediation as a means for confronting this problem; i.e. treating poor environments with these plants, without the need to excavate soil. Moreover, the idea is based on the microbiological properties of the soil itself to measure this technique: the mass of its microbian community, its activity and its biodiversity. The title of her PhD thesis is Evaluation of the efficiency of metal phytoremediation processes with microbiological indicators of soil health. Technique adapted to each condition Ms Epelde investigated, above all, pseudometalophyte plants - which grow in mining environments -, and the reaction they have to metals. To begin with, she linked Lanestosa of the thlaspi caerulescens species with zinc and cadmium. Lanestosa is a traditional mining town in the Encartaciones region near Bilbao and its namesake plant has optimum conditions for continuous phytoextraction (a process for differentiating metal from the rest of the elements). According to the research, it is capable of withstanding great concentrations of metal and also of accumulating considerable quantities of zinc and cadmium in its tissues that are in contact with the air. As with hyperaccumulator species such as this, large-sized plants are also effective. For example, sorghum has great potential for phytoextracting zinc and cadmium. On the other hand, to phytoextract soils contaminated by lead, Ms Epelde opted for combining plants and chemistry, on the one hand using thistle (a plant of large dimensions) and, on the other, a chelating agent. She tested them with two chelating substances: EDTA and EDDS and concluded that, while EDTA is more effective for phytoextraction and less toxic for thistle plants, EDDS is less toxic for the soil microbian community and biodegrades rapidly. In highly contaminated soils (zinc, cadmium and lead), Ms Epelde, instead of extraction, opted for stabilisation with grass crops, to this end using lolium perenne (ryegrass) and fertiliser. Particularly effective is cattle purine as it enhances the properties of the mining soils and reduces the toxicity of metals. Finally, Ms Epelde combined three species of plants with different strategies for tolerance to metals, in order to see how they worked together. The three were thlaspi caerulescens (Alpine pennycress), rumex acetosa (sorrel) and festuca rubra (red fescue). It was shown that this technique has a great future. In fact, the thlaspi caerulescens causes the growth of the other two species and the rumex acetosa extracts more zinc when operating in conjunction with the thlaspi caerulescens. Microbiological properties as indicator Ms Epelde has shown that microbiological properties are effective for measuring phytoremediation. Microbiological properties are bioindicators of great value, given their sensitivity, speed of response and comprehensive character. Helped by this technique, she concluded that the key is phytoremediation plants, rather than phytoremediation itself. Just the presence of these plants improves the health of the soil and, moreover, does so in a very short time, through increase in activity and functionality of the microbian community in the soil. However, more time is needed for the phytoremediation to clean up the contamination left by metals in the soil. In any case, as the most important thing is to recover the health of the soil, the aim is accomplished. Elhuyar Fundazioa |
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| Related Phytoremediation Current Events and Phytoremediation News Articles Arsenic hyperaccumulating ferns: How do they survive? Arsenic is toxic to most forms of life, and occurs naturally in soil and ground water in many regions of the world. Common plants can eliminate indoor air pollutants Air quality in homes, offices, and other indoor spaces is becoming a major health concern, particularly in developed countries where people often spend more than 90% of their time indoors. 'Green Clean:' Researchers Determining Natural Ways To Clean Contaminated Soil Researchers at North Carolina State University are working to demonstrate that trees can be used to degrade or capture fuels that leak into soil and ground water. Through a process called phytoremediation - literally a "green" technology - plants and trees remove pollutants from the environment or render them harmless. Plant Microbe Shares Features with Drug-Resistant Pathogen An international team of scientists has discovered extensive similarities between a strain of bacteria commonly associated with plants and one increasingly linked to opportunistic infections in hospital patients. Mechanisms of plant-fungi symbiosis characterized by DOE Joint Genome Institute Plants gained their ancestral toehold on dry land with considerable help from their fungal friends. Now, millennia later, that partnership is being exploited as a strategy to bolster biomass production for next generation biofuels. Fighting pollution the poplar way: Trees to clean up Indiana site Purdue University researchers are collaborating with Chrysler LLC in a project to use poplar trees to eliminate pollutants from a contaminated site in north-central Indiana. Scientists ramp up ability of poplar plants to disarm toxic pollutants Scientists since the early '90s have seen the potential for cleaning up contaminated sites by growing plants able to take up nasty groundwater pollutants through their roots. Then the plants break certain kinds of pollutants into harmless byproducts that the plants either incorporate into their roots, stems and leaves or release into the air. Researchers discover way to transport environmental arsenic to plant leaves in new clean-up strategy Environmental arsenic pollution is a serious and growing environmental problem, especially on the Indian subcontinent. Researchers at the University of Georgia had, several years ago, used genetic techniques to create "arsenic-eating" plants that could be planted on polluted sites. Heavy Metal Rocks Plant Cells too Heavy metals can trigger widely varying stress reactions in plants. A team at the Campus Vienna Biocenter was now able to provide evidence for this in a research funded by the Austrian Science Fund (FWF). The results, now awaiting publication, are an important basis to comprehend how plants cope with an increase in heavy metal concentrations in the soil - and how these abilities can be profitably utilised. Cornell Research is Key - New Company Promises to Detoxify Pollutants with Plant Biologicals A company formed as a spin-off from research conducted at Cornell University, the University of Surrey and the University of Naples, Italy, will provide biological systems that detoxify heavily contaminated soil and water. "Our goal is to develop biological products with broad capabilities for the detoxification of polluted soils or sediments and waters," said Cornell University horticultural scientist Gary Harman, one of the founding partners of the new company, who works at the New York State Agricultural Experiment Station, in Geneva, NY. "These products will provide low cost alternatives to commonly used chemical or physical cleanup methods. Biological methods for the rem More Phytoremediation Current Events and Phytoremediation News Articles |
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