Pb, Zn, Cu, Ni And Co Contents of Water and Sediments, in Relation to Phytoremediation and Translocation by Water Hyacinth (Eichhornia Crassipes Mart. Solms.) At Some Creeks of the Great Kwa River, Southeastern Nigeria (Published)
A passive phytoremediation study to investigate the environmental purification efficacy of water hyacinth (Eichhornia crassipes) was carried out at Mbat-Abiati and Oberekkai Creeks of the Great Kwa River in Southeastern Nigeria. The study assessed the levels of Pb, Zn, Cu, Ni and Co in the water column and underlying sediments (abiotic monitors) in comparison with their levels in E. crassipes (biomonitor). Generally, observed values of heavy metals in sediment and water hyacinth of the two Creeks did not vary significantly (p>0.05), and the sequence that was frequently encountered in the accumulation of the heavy metals was: SEDIMENT>PLANT ROOTS>PLANT LEAVES>WATER. Relative Accumulation Indices (RAI) revealed that the concentration of the heavy metals in the sediments are much higher than values recorded for the waters. This appear normal since sediments are reservoirs for all contaminants and dead organic matter descending from the ecosystem above. The pattern of heavy metal concentrations in the organs of E. crassipes are closely associated with that of its geological substrate (water and sediments). Although zinc displayed the highest accumulation in both root and leaves tissues, and appeared more mobile from roots to leaves than other heavy metal, the bioconcentration factor (BCF) revealed Co as the metal with the highest phytoaccumulation capability in the area, followed by Ni, Cu, Pb and Zn, in that order. Indication from the study is that water hyacinth (Eichhornia crassipes) can effectively absorb and translocate Pb, Zn, Cu, Ni and Co, even when the concentrations of the metals in the abiotic components of the environment is low.
Keywords: Bioaccumulation, Nigeria, Phytoremediation, Translocation, Water Hyacinth
Environmental Geochemical studies on the effects of coal mining in Akwuke- Awkanawnaw, Enugu, and Southeastern Nigeria (Published)
Geochemical media such as water, soil, blackshales and plants were collected around Akwuke community in Awkanawnaw in Enugu area of southwestern Nigeria, and analysed for physicochemical parameters, inorganic ions /salts and heavy metal abundance. The ultimate goal was to investigate the geochemical environment and ascertain if the abandoned Okpara coal mine has any contamination effect on geoenvironment. The measured pH range of 3.98-4.42 renders the water as acidic to moderately acidic and consequently unsuitable drinking purposes, vegetation and aquatic life and wild life. Other physical and inorganic /organic parameters in water such as TDS, EC, Turbidity, TOC, total harness, Cl-, NO3, PO4, F, CN, Ca, Mg, Na and K all fall below recommended standard for potable water guidelines by WHO and EU and they do not portend any health threat to the end-users. Heavy metals results indicated that Fe comprise the most abundant metal in all the media except in plants where Zinc top the list. This is evidence that Fe is of main interest in all the media. It is only in soil sample s that the elements: Fe, Zn, Cr, Cd, Pb, Mn, Cu and Ni exceed standards by US EPA for agricultural soils. This high concentration of potentially toxic metals in soils and acidic water condition constitute a threat to the ecosystem. Specifically, acidic and Fe polluted waters are not benign for fish growth and survival of aquatic biota. Also, acidic and ferruginous waters corrode borehole installation materials and produce iron stained water with characteristic reddish colour and offensive odour. Assessment of the comparative heavy metal abundance in water plants, soil and black shale revealed that there is more heavy metal enrichment loading in soil than other media. The hazard potential is that soils serve as a source that can release heavy metals into other media by various processes of remobilization.Therefore, phytoremediation can be adopted in the for heavy metal attenuation in soils.
Keywords: Ecosystem, Phytoremediation, geoenvironment, potentially toxic
Phyto-Microbial Degradation of Glyphosate in Riyadh Area (Review Completed - Accepted)
Greenhouse studies were conducted to determine the ability of plant Amaranth, Amaranthus caudate and two isolated bacterial strains from rhizosphere region for cleaning up glyphosate residues in soil and plants. The analytical study of the biodegradation of glyphosate was carried out in the laboratory conditions. Amaranth, Amaranthus caudate and two isolated bacterial strains namely Pseudomonas aeruginosa and Bacillus megaterium could degrade glyphosate in 5 days. These results suggested that phytoremediation could accelerate the degradation of glyphosate residues in plants and in rhizosphere region as well. Glyphosate had strong effect on bacterial DNA where many DNA bands were affected. This could be explained that the effect of herbicide glyphosate on the protein profile may reflex somehow DNA mutation occurred during the assimilation of those toxic compounds. Therefore, the alteration occurred in both DNA and protein profiles is considered a degree of tolerance that lead to DNA mutation to cope with the assimilation of this compound. Therefore, the phytoremediation way could be a promising tool in program is to protect public health and the environment by ensuring the safety and availability of herbicides and pesticide alternatives.
Keywords: Amaranthus caudate, Bacillus megaterium, Glyphosate, Phytoremediation, Pseudomonas aeruginosa