Phytoremediation plants

Burken JG, JL Schnoor (1996) Phytoremediation plant uptake of atrazine and role of root exudates. J Environ Eng 122 958-963. 

Some potential disadvantages associated with phytoremediation/plant-assisted remediation techniques include the following ... 

Lee Newman (phytoremediation plant nanoparticle interactions ph)doremediation of groundwater contaminated with industrial organic pollutants hyperspectral imaging of plants to determine contaminant exposure and plant microbe interactions to increase plant productivity and decrease stress responses). Past President, International Phytotechnology Society College of Environmental Science and Forestry, State University of New York (SUNY), Syracuse, NY... 

A recent suggestion has been to use plants to stimulate the microbial degradation of the hydrocarbon (hydrocarbon phytoremediation). This has yet to receive clear experimental verification, but the plants are proposed to help deUver air to the soil microbes, and to stimulate microbial growth in the rhizosphere by the release of nutrients from the roots. The esthetic appeal of an active phytoremediation project can be very great. 

Phytoremediation is also being developed for dealing with soils contaminated with high levels of selenium in California again B.juncea seems to be particularly effective in accumulating the contaminant from soil, and all plants tested were more effective at removing selenate than selenite (92). This is an interesting contrast to bacterial systems, where selenite reduction is more commonly found than selenate reduction. 

Hegde RS, JS Fletcher (1996) Influence of plant growth stage and season on the release of root phenolics by mulberry as related to development of phytoremediation technology. Chemosphere 32 2471-2479. 

Salt DE, RD Smith, I Raskin (1998) Phytoremediation. Annu Rev Plant Physiol 49 643-668. 

Uchida E, T Ouchi, Y Suzuki, T Yoshida, H Habe, I Yamaguchi, T Omori, H Nojiri (2005) Secretion of bacterial xenobiotic-degrading enzymes from transgenic plants by an apoplastic expression system applicability for phytoremediation. Environ Sci Technol 39 7671-7677. 

Lunney AA, BA Zeeb, KJ Reimer (2004) Uptake of weathered DDT in vascular plants potential for phytoremediation. Environ Sci Technol 38 6147-6154. 

Phytofiltration, a specific strategy of phytoremediation, is the use of plants to remove contaminants from water and aqueous waste streams. Three different systems (Figure 10.1) can be considered within this strategy (a) rhizofiltration (the use of hydroponically cultivated plant roots),31112 (b) constructed wetlands (CWs) and lagoons, and (c) bioadsorbents-based systems.1... 

The phytofiltration of Pb(II) and Cd(II) has been also studied using species of Salvinia. S. minima Baker is a small free-floating aquatic fern native to Mexico, Central America and South America. It has been proved to be an excellent aquatic phytoremediator and hyperaccumulator of Cd(II) and Pb(II).72,76 The relevance of using a compartmentalization analysis (CA) complementary to the use of BCFs and metal removal kinetics by plants has been demonstrated using S. minima... 

Metal removal in SSFCWs has been recently focused on metal elimination from synthetic water and different wastewaters,66-86 on the evaluation of the effects of season, temperature, plant species, and chemical oxygen demand (COD) loading on metals removal,87 and on the accumulation of metals in wetland plant species and sediments.88-89 Recent reviews on heavy metal phytoremediation wetlands are also available.48... 

In natural conditions, Ceratophyllum demersum and Potamogeton pectinatus L. have been found to be effective adsorbents of Cd(II), Cu(II), and Pb(II). The adsorption percentage of the metals onto plant surfaces followed the pattern Pb(II) > Cu(II) > Cd(II). P. pectinatus biomass adsorbed a higher content of heavy metals than C. demersum. According to the results, both species are of interest in the phytoremediation and biomonitoring studies of polluted waters.122... 

Pilon-Smits, E., Phytoremediation, Annual Review Plant Biology, 56, 15-39, 2005. 

Padmavathiamma, P.K. and Li, L.Y., Phytoremediation technology Hyper-accumulation metals in plants, Water, Air, and Soil Pollution, 184, 105-126, 2007. 

Dushenkov, S. and Kapulnik, Y., Phytofiltration of metals, in Phytoremediation of Toxic Metals Using Plants to Clean Up the Environment, Raskin, I. and Ensley, B.D., Ed. Wiley-Interscience, New York, 2000, pp. 89-106. 

Natarajan, S., Stamps, R.H., Saha, U.K., and Ma, L.Q., Phytofiltration of arsenic-contaminated ground-water using Pteris Vittata L. Effect of plant density and nitrogen and phosphorus levels, International Journal of Phytoremediation, 10 (3), 222-235, 2008. 

Rai, P.K., Heavy metal pollution in aquatic ecosystems and its phytoremediation using wetland plants An ecosustainable approach, International Journal of Phytoremediation, 10, 133-160, 2008a. 

Goulet, R.R., Lalonde, J.D., Munger, C., Dupuis, S., Dumont-Frenette, G., Premont, S., and Campbell, P.G.C., Phytoremediation of effluents from aluminum smelters A study of A1 retention in mesocosms containing aquatic plants, Water Research, 39, 2291-2300, 2005. 

Fritioff, A. and Greger, M., Aquatic and terrestrial plant species with potential to remove heavy metals from stormwater, International Journal of Phytoremediation, 5 (3), 211-224, 2003. 

Weis, J.S. and Weis, P., Metal uptake, transport and release by wetlands plants implication for phytoremediation and restoration, Environment International, 30 (5), 739-753, 2004. 

Liao, S.W. and Chang, N.L., Heavy metal phytoremediation by water hyacinth at constructed wetlands in Taiwan, Journal of Aquatic Plant Management, 42, 60-68, 2004. 

Factors that affect the accessibility of chemicals to plant roots include hydrophobicity, polarity, sorption properties and solubility. In order to apply phytoremediation techniques to soils polluted by organic contaminants, the contaminant must come into contact with the plant roots and be dissolved... 

Different forms of phytoremediation may require different types of plants and be relevant for specific types of contaminants (Table 14.8). In the following section, each remediation form is presented separately. 

Typical Plants Used in Various Phytoremediation Applications... 

Phytoremediation in the root zone. Proteins and enzymes produced by the plant can be exuded by the roots into the rhizosphere. These plant products target contaminants in the surrounding soil, leading to precipitation or immobilization in the root zone. This mechanism within phytostabilization may reduce the fraction of the contaminant in the soil that is bioavailable. 

The design of a phytoremediation system is determined by several factors associated with the contaminants (type, concentration, and depth), the conditions at the site, the plants, the level of cleanup required and the available time. Extraction techniques have different design requirements than immobilization or degradation methods. Nevertheless, it is possible to specify a few design factors that are a part of most phytoremediation efforts. 

These maximum depths are not likely to occur in most cases. The effective depth for phytoremediation using most nonwoody plant species is likely to be only 30 or 61 cm (1 or 2 ft). Most accumulators have root zones limited to the top foot of soil, which restricts the use of phytoextraction to shallow soils. The effective depth of tree roots is likely to be in the few tens of feet or less, with one optimistic estimate that trees will be useful for extraction of groundwater up to 9 m (30 ft) deep.41-58... 

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