Browsing by Author "Hogard, J.N."
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Assessment of heavy metal contamination and macro-nutrient content of compose for environmental pollution control in Ghana.(Global Journal of Environmental Research 2(3): 133-139., 2008) Hogard, J.N.; Fobil, J.N.; Ofosu-Budu, G.K.; Carboo, D.; Ankrah, N.A.; Nyarko, A.This study examined macro-nutrient content of solid waste compost to determine the potential of the compost for soil fertility amelioration in Ghana. Heavy metal concentrations in the compost were also examined to assess the potential health implication of compost application in urban and peri-urban agriculture. It was observed that the overall NPK concentration was low in the different compost types, but generally total N and K were greater in agricultural waste compost compared to municipal solid waste (MSW) composts. The agricultural waste compost was also richer in organic carbon. In terms of toxicity concerns, heavy metals concentration (Ni, Zn, Cu and Cd) were generally low in the different types of composts and within permissible, Australia standards for compost products. However, lead (Pb) concentration in mixed MSW composts was significantly high in the dry season, exceeding the Australian limit of 150 mg/kg Pb, required for unrestricted compost use. There was considerable seasonal variation in the heavy metal levels in the composts made from open windows process, with reduced levels in the rainy season. It appeared that seasons affected mixed waster characteristics, which affected compost quality. It was therefore concluded that seasons and composting processes, to some extent, were important determinants of the levels of toxic metal concentrations in final compost products in Ghana.Item Isolation and identification of some plant growth promoting substances in compost and co-compost.(International Journal of Virology 4(2): 30-40., 2008) Hogard, J.N.; Fobil, J.N.; Carboo, D.; Ofosu-Budu, G.K.; Ankrah, N.A.; Nyarko, A.In this study, plant growth hormones in compost or co-compost prepared from human excreta and/or municipal solid waste were extracted and identified. Water (deionized) or 80% methanol (chilled) extracts were prepared from the composts for the isolation and identification of plant growth substances. The methanolic extracts of plant growth hormones fraction was further partitioned into cytokinin (fraction) using ethyl acetate and n-butanol; auxins (fraction) using diethyl ether and gibberellins (fraction) using sodium hydrogen carbonate and n-butanol. Five different concentrations of standard plant growth hormones; Benzyl Amino Purine (BAP), Gibberellic Acid (GA3) and Indole-3-Acetic Acid (IAA) were prepared and used in a bioassay test to compare the effects and concentration of the extracted plant growth hormones from the compost and co-compost. The presence of some plant growth hormones in the extracted samples from compost or co-compost was confirmed using the relative fluidity, (Rf) values of the co-chromatography using a standard hormone and the extracted plant growth hormones. The results indicated the presence of plant growth substances such as IAA, GA3 and cytokinins. In co-compost, the concentration of hormone were found to be 68.3 to 345.1 mg kg-1, 61.9 to 185.8 mg kg-1 and 250.4 to 312.7 mg kg-1 for auxins, cytokinins and gibberellins, respectively. Whereas in compost 42.0 to 248.8 mg kg-1, 33.1 to 198.3 mg kg-1 and 10.1 to 200.2 mg kg-1 of auxins, cytokinins and gibberellins, respectively were found.