Use of Bio-Resources for Remediation of Soil Pollution

In recent years, economic boom in fast developing countries has been witnessed with spectacular progress in industri- alization and concurrent progress in modern agriculture. Such development is however not without any socio-political and environmental side effects. A major concern has been the environmental pollution. If the current unabated disposal of various forms of wastes to agricultural lands is continued, the inherent capacity of soil to support agricultural pro- duction and sustain other ecosystem services will be in peril. Heavy metals with soil residence times of thousands of years present numerous health hazards to higher organisms. They are also known to decrease plant growth, ground cover and have a negative impact on soil biodiversity. Inorganic and organic contaminants typically found in urban areas are heavy metals and petroleum derived products. The presence of both types of contaminants on the same site presents technical and economic challenges for decontamination strategies. In this article we have reviewed the devel- opments to ameliorate the contaminated soils, with special emphasis on biological approaches, which have shown po- tential to low-cost remediation of soil pollution. Also the limitations of such approaches and direction of further re- search have been highlighted.

Seasonal variability of water quality by physicochemical indexes and traceable metals in suburban area in Kikwit,Democratic Republic of the Congo

Water resource contamination is still a major concern in several regions of developing countries espe-cially in sub-Saharan countries in which polluted waters pose serious risks to human health and the environment.The seasonal variation of the physicochemical parameters including pH,temperature(T),electrical conductivity(EC),dissolved oxygen(O_(2)),dissolved organic carbon(DOC),total organic carbon(TOC),and trace metals were assessed in water samples collected from wells(n=3)and two rivers which were the River Lukemi(RLK,n=3)and River Luini(RLN,n=2)located in the City of Kikwit(Province of Kwilu,Democratic Republic of the Congo).Samples were collected during the dry and wet seasons.The concentration of trace metals(Cr,Mn,Co,Ni,Cu,Zn,As,Mo,Ag,Cd,Sn,Sb,and Pb)in water was measured using Inductively Coupled Plasma Mass Spectrometry(ICP-MS),and soluble ions(Na^(+),K^(+),NH_(4)^(+),SO_(4)^(-),NO_(3),and Cl^(-))analysis was performed using lon Chromatography.The results indicate the seasonal difference in the physicochemical composition of water e.g.,the pH was lower in the wet compared to the dry season.pH values during the wet season ranged from 4.12 to 5.60 in wells and from 5.55 to 6.31 in rivers while the dry season values ranged from 6.27 to 6.98 in wells and from 7.09 to 7.44 in rivers.The concentrations of soluble ions and other physicochemical par ameters(O_(2),DOC and TOC)also varied with the seasons,being higher in the wet and lower in the dry season.With the exception of Mn,the average concentrations of other trace metals measured in water samples from wells and rivers met the World Health Organization(WHO)guidelines for drinki ng/domestic water quality.Mn concentration in water samples analysed ranged between 634 to 812 and 1352-1741μgL^(-1) during the dry and wet seasons,respectively.These results imply that the high concentration of Mn in the water samples may be explained by the geological origin and result of natural weathering processes.In general,according to the parameters analysed,the water samples taken from the sites studied in both seasons appear to meet drinking water standards according to the WHO guidelines but with the two exceptions of the pH and Mn.