Studies on Municipal Solid Wastes Dumping on Soil Anions, Cations and Selected Enzymes Activities at Njoku Sawmill Waste Dumpsite, Owerri Municipal, Imo State, Nigeria

In this study, the physicochemical parameters, anions, exchangeable cations, tracemetals concentrations and selected soil enzymes activities of Njoku solid waste dumpsite Owerri municipal, Nigeria were investigated. Soil temperature (28.8 ± 0.04 – 33.9±0.01oC), pH of the heavily polluted points (7.3 ± 0.01 – 7.4±0.03) moisture content (26.74±0.10) were significantly higher (P< 0.05) compared to control soil samples. Similarly dumpsite soil nitrate level, percentage organic carbon, organic matter, sulphate and phosphate ions were significantly (P<0.05) increased with increased waste dumping. All the exchangeable cations and trace metals concentrations investigated were higher (P<0.05) than control levels. However, while the dumpsite soil alkaline phosphatase enzyme activity remained unaffected by waste dumping (p>0.05), acid phosphatase, dehydrogenase, lipase, hydrogen peroxidase and urease enzymes activities were enhanced (p<0.05) at the heavily polluted points of the dumpsite compared to control samples. Although the dumping of solid wastes increased the soil nutrients, most were made unavailable to plants and microorganisms.Keywords: Solid wastes, soil, anions, cations enzymes activitie

Nutritional and chemical value of Amaranthus hybridus L. leaves from Afikpo, Nigeria

The nutritional and chemical value of Amaranthus hybridus were investigated using standard analytical methods in order to assess the numerous potential of the plant leaves. The Proximate analysis showedthe percentage moisture content, ash content, crude protein, crude lipid, crude fibre and carbohydrate of the leaves as 84.48, 13.80, 17.92, 4.62, 8.61 and 52.18%, respectively while its calorific value is 268.92 Kcal/100 g. Elemental analysis in mg/100 g (DW) indicated that the leaves contained sodium (7.43), potassium (54.20), calcium (44.15), Magnesium (231.22), Iron (13.58), Zinc (3.80) and phosphorus (34.91). The vitamin composition of the leaves in mg/100 g (DW) was -carotene (3.29), thiamine (2.75), riboflavin (4.24), niacin (1.54), pyridoxine (2.33), ascorbic acids (25.40) and -tocopherol (0.50). Seventeen amino acids (isoleucine, leucine, lysine, methionine, cysteine, phenylalmine, tyrosine, threonine, valine, alanine, arginine, aspartic acid, glutamic acid, glycine, histidine, proline and serine)were detected. The chemical composition in mg/100 g (DW) for alkaloid, flavonoid, saponin, tannins, phenols, hydrocyanic acid and phytic acid were 3.54, 0.83, 1.68, 0.49, 0.35, 16.99 and 1.32, respectively.Comparing the nutrient and chemical constituents with recommended dietary allowance (RDA) values, the results reveal that the leaves contain an appreciable amount of nutrients, minerals, vitamins, aminoacids and phytochemicals and low levels of toxicants

Seasonal impact on phyto-accumulation potentials of selected edible vegetables grown in Ishiagu quarry mining effluent discharge soils

Seasonal impact on soil trace metals and phytoaccumulation potentials of Cucurbita pepo, Cucumis sativus and Taliferia occidentalis grown in Ishiagu quarry mining effluent discharge soils were investigated. Soil samples were collected 200 m (sample C), 100 m (sample B) away from discharge point (sample A) in wet and dry seasons. Trace metals were analysed using atomic absorption spectrophotometer. Results reveal a significant decrease in levels of trace metals distance away from discharge points in the order A>B>C. Findings from the study show significant increase in level of soil trace metals in dry season compared to wet season. Phyto-accumulation potentials of the vegetables showed significant increase in level of trace metals in roots and shoots in dry season compared to wet season. Level of these metals were significantly higher compared to control. This is indicative of the potential risk associated with consumption of vegetables grown in these sites especially in dry seasons. The rural dwellers should be discouraged from planting edible vegetables around Ishiagu quarry mining effluent discharge soils in order to reduce excessive build-up of these metals in the human food chain.Keywords: Phyto-accumulation, trace metals, quarry mining, discharge soils, seasonal impac

Oxidative stress potential of Lead-Zinc mining on selected plants growing in Ishiagu, Nigeria

The study evaluated some biochemical and physiological properties of selected plants growing in the Ishiagu lead-Zinc mining area, Nigeria, in order to assess oxidative stress. Using sampling without replacement, twelve plants were randomly selected from the thirty five identified. Control samples were collected from a non-mining area about twenty five km away from the study area. Results showed that statistically significant differences were not found between sites with respect to biochemical parameters (ascorbic acid content, pH, total chlorophyll content and relative water content) at p>0.05. Physiological parameters (abaxial and adaxial stomata pore size) showed significant difference between site at p>0.05. With respect to plants, values for all parameters were statistically significant at p>0.05 except for relative water content, possibly due to stomatal occlusion from particulate contamination at the mining area. The lower mean values for pH, total chlorophyll content, and stomata pore size, and the higher mean ascorbic acid values of plants at the mining area is suggestive of oxidative stress from heavy metal accumulation. Stress is very likely to have less potential of mitigating air pollution and providing other environmental services. Such plants also suffer from compromised nutritive and phytotherapeutic values, as well as being potential sources of pollutant intoxication of man and animals through dietary origin. Key Words: Heavy metals, Plants, Physiochemical status, Oxidative stress, Health risk