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Phytoremediation of cadmium in contaminated soil | |
Author | Ariyawat Prabamroong |
Call Number | AIT Thesis no.EV-06-3 |
Subject(s) | Cadmium Soils--Cadmium content |
Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development |
Publisher | Asian Institute of Technology |
Abstract | Cadmium contamination of soil causes major environmental and human health problems. A need, therefore, exists for cost-effective remediation procedures. Phytoremediation, the use of plants to extract contaminants from soils, has revealed great potential. The overall objective of this research was to screen, investigate and quantify the capability of Andrographis paniculata (Bumf) Nees and Nicotiana tabacum L. for Cd uptake and removal in pot culture experiment with and without compost added. Two micronutrients, zinc(Zn) and iron(Fe) were applied to a cadmium-contaminated soil (50 ppm Cd), and the uptake of cadmium into the two plant spices was indicated that Zn and Fe leaded to a decrease of Cd uptake and the occurring of plant symptoms possibly caused by zinc and iron toxicity in all two species. In the other pot culture experiment study conducted with 10 to 200 mg Cd. kg' of soil indicated that N. tabacum was more effective in removing Cd from soil than A. paniculata as indicating by the value of bioconcentration factor (BCF). The highest accumulated concentration of Cd by N. tabacum was at round up 474, 387 and 326 g.g' DW in roots, stems, and leaves, respectively at the highest Cd added. The results showed that about 83-90% and 27-43%, of the total amount of Cd uptake were localized in plant roots of A. paniculata and N. tabacum, respectively and 10-17% and 59-68% were translocated to the aboveground plant parts of A. paniculata and N. tabacum after the 8 growing weeks under different Cd concentration applied. Correlation (r) between soil Cd concentration and plant Cd accumulation was significantly in A. paniculata (at 1st, 4th, and 8th week) and N. tabacum (1st, 2nd, and 4th week) (p<0.05). A significant accumulation of zinc was correlated with soil Cd concentrations after 2nd and 4`h week for A. paniculata and ls` and 8th week for N. tabacum (p<0.05). N. tabacum grown on the two different soils, The Cd contents were localized in the descending order: leaf>stem>root and stem>leaf 'root of the growing on two different type soils without compost and that with compost added, respectively. In our study, it was demonstrated that addition of compost leaded to a decrease of BCF value in Cd-contaminated soil and an increase in uncontaminated soil (reference soil). This could be explained that compost would form complexes with Cd in soil, thus reducing Cd bioavailability. As a result Cd uptake by the plants was reduced. A possible estimation for clean up, dry leaf biomass of N. tabacum at about 0.25-0.33 t.ha"' which had grown on different spiked Cd concentration soils (10, 20, 50, and 100 mg Cd. kg-') could remove Cd 31-41, 22-29, 56-74 and 103 -136 g Cd. ha-1 in two months |
Year | 2006 |
Type | Thesis |
School | School of Environment, Resources, and Development (SERD) |
Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
Academic Program/FoS | Environmental Engineering and Management (EV) |
Chairperson(s) | Preeda Parkpian; |
Examination Committee(s) | Shipin, Oleg ;Sombun Techapinyawat |
Scholarship Donor(s) | Royal Thai Government Fellowships ; |
Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2006 |