Phytoremediation of heavy metals by Trifolium alexandrinum

Abstract

The release and persistence of toxic heavy metals into the natural environment is a serious concern especially in urban areas. The problem of heavy metal pollution is gaining momentum from year to year as more and more amounts of heavy metals are extracted from their ores and released into the environmental segments (water, air and soil) during processing or afterwards. Heavy metals are essentially nonbiodegradable and therefore accumulate in the environment and subsequently find their way into the food chains. Contamination of food chains by toxic heavy metals is an unwanted outcome of industrialization and unsustainable development. This contamination is a risk to the health of all organisms including humans. Entrance of toxic heavy metals (through absorption, inhalation and ingestion) into the human body beyond threshold limits causes many diseases and health abnormalities. Therefore, effective remediation of heavy metal pollution is a top priority. The different physico-chemical methods used for this purpose generally suffer from serious limitations. Phytoremediation is seen as an alternative green solution to the problem. The present study reports phytoremediation of Cd, Pb, Cu, and Zn by Trifolium alexandrinum, which is a suitable candidate plant species for this purpose. T. alexandrinum was grown in a simulated heavy metal-contaminated soil. Root bioconcentration factor values of T. alexandrinum for Zn, Pb, Cu and Cd were 4.242, 1.544, 1.071, and 0.604 respectively.

Growth and volatile compounds of Martianthus leucocephalus exposed to heavy metal stress

“…Roots accumulated more metals than leaves and stems, indicating low translocation from the root to the aerial part of the plant (ALI et al, 2012). In addition, the results confirmed that Cu and Zn are deemed to have low mobility in plants (MARSCHNER, 2012).…”

Heavy Metal Concentrations in Some Common Medicinal Plants from Different Geographical Locations in Douala, Cameroon

“…The study of Lion et al (2016) observed that from all the plants studied, the concentrations of trace metals in the roots were more than those recorded in the shoot with a significant difference (p<0.05). Hazrat et al (2012) showed that the concentrations of trace metals were greater in roots than in shoots. A similar observation was also made by Peralta et al (2001) where alfalfa plants accumulated more of the trace metals in the roots than any other part.…”

An investigation of the bioaccumulation of chromium and uranium metals by Cynodon dactylon: A case study of abandoned New Union Gold Mine Tailings, Limpopo, South Africa

“…The bioconcentration factor and translocation factors were calculated as per procedure of Hazrat et al (2012). The bioconcentration factor (BCF) and translocation factor (TF) data was then log transformed and then analysed for Pearson correlation coef- …”