This study investigated the effect of inoculation of Pleurotus tuber-regium, a Nigerian white rot fungus, period of incubation, different levels of contamination on cutting fluids degradation in contaminated
soil over 30, 60, and 90 days. Control for different levels of cutting fluids was also used to compare rates of bioremediation
of the contaminant in the soil. At the end of each incubation period, the mycelia-ramified substrate was separated from the
soil layer and dried. The soil samples were analyzed for physico-chemical parameters; total petroleum hydrocarbon, lignin
content by determining the acid detergent fraction (ADF), heavy metals content of the soil using flame atomic absorption spectrophotometer,
and changes in the polyphenol oxidase and peroxidase activities were also determined after 1, 2, and 3 months. P. tuber-regium improved the nutrient status of the soil and increased enzyme activity was recorded. A reduction in the pH and heavy metal
contents of the soil at all levels of cutting fluids concentrations was detected. The lignin in the rice straw decreased from
34.50% in the control to 8.06% at 30% cutting fluids concentration after 3 months of incubation. The highest TPH loss of 30.84%
was recorded at 20% cutting fluids contamination after 3 months compared to 13.75% at the onset of the experiment. The improvement
of the nutrient contents of the soil, bioaccumulation of heavy metals, degradation of TPH, lignin, and increased activity
of polyphenol oxidase and peroxidase was due to biodegradation of the cutting fluids. 相似文献
Environmental Geochemistry and Health - A multidisciplinary approach to research affords the opportunity of objectivity, creation of new knowledge and potentially a more generally acceptable... 相似文献
Environmental Chemistry Letters - Lithium batteries are increasingly used to store energy, but are limited by high cost, safety concerns, leaking of electrolytes, and low capacity.... 相似文献
In Nigeria, as in most countries, institutional barriers to successful rural development exist and need to be addressed. In Sokoto State, a variable and unpredictable Sahelian climate in combination with conditions of high population growth, low levels of income, and environmental degradation, create and intensify institutional challenges. This study examines the sustainability of government initiatives regarding the provision of agricultural inputs, assistance and extension services to farmers, and the extent to which agency efforts are coordinated and integrated, particularly regarding water management. In some cases, rural development agencies demonstrated the capability to meet the needs of the people. Some farmers were satisfied with government assistance and in some areas the tube well programme was quite successful. Yet in Sokoto State many institutional barriers to sustainable rural development exist and need to be addressed. In general, implementation strategies and management procedures appeared narrowly focused and placed little emphasis on coordination and integration among rural development agencies. The result was often inappropriate overlap or oversights in activities . 相似文献
BACKGROUND: Road-traffic crashes and fatalities constitute major social and economic issues in South Africa. They are a major cause of morbidity and mortality comparable to HIV/AIDS, homicides, and some chronic diseases. METHODS: Road-traffic accident data for the year 2003 obtained from the Department of Transport, Pretoria, South Africa were used for this study. The valuation of the costs of road-traffic crashes and fatalities in South Africa is based on the gross output or human capital approach. RESULTS: 10,197 fatal road crashes and 12,353 fatalities were reported during the study period. More than 50% of the fatal road crashes and fatalities occurred in only three out of 11 provinces. The Northern Cape, which is the least populated province, had the highest fatal road crashes per 100,000 population and fatalities per 100,000 population. The number of road-traffic fatalities in the rural areas was 2.7 times that in the urban areas. The total costs of the road-traffic fatalities which was about R 8 billion (>US$ 1 billion) is about 0.6% of the country's nominal GDP for 2003. 60% of the cases and costs of road-traffic fatalities involved persons aged 20-39 years, although this age group is only 27% of the country's population. The rural areas accounted for 73% and the urban areas 27% of the total costs of fatal road-traffic crashes. CONCLUSION: Those living in the rural areas of the South African society and those aged 20-49 years constitute high-risk groups of road-traffic crashes and fatalities. They are also responsible for most of the attendant costs of fatal crashes and fatalities in the country. 相似文献
Environmental Science and Pollution Research - Waste wigs are often disposed off in their volume on landfills, thus constituting a nuisance to the environment. Recycling these wigs in masonry... 相似文献
This study reports the level of total petroleum hydrocarbons (TPH) and trace heavy metals (lead, copper, and cadmium) in soil samples collected randomly from Iyana–Iba garage, Lagos State University bus stop, Adeniran Ogunsanya College of Education bus stop, and a control site off Lusada–Atan road, near Crawford University, Igbesa, Ogun state. TPH was estimated gravimetrically after Soxhlet extraction and column clean up, while soil metals were determined by atomic absorption spectrometry using mineral acid digestion. For TPH, the sites have mean values of 19.43 ± 1.27, 16.11 ± 1.85, and 11.43 ± 4.33 mg/g with a control mean value of 0.33 ± 0.16 mg/g. For trace heavy metals, cadmium was not detected. However, the mean levels of lead are 4.24 ± 3.10, 3.72 ± 0.60, and 3.70 ± 1.32 μg/g, respectively, whereas mean copper concentrations are 20.63 ± 9.02, 19.35 ± 3.61, and 16.76 ± 3.02 μg/g in all sites, respectively, compared to the control mean of 0.25 ± 0.13 and 5.99 ± 1.23 μg/g for lead and copper, respectively. Sites studied have higher levels of TPH and metals compared to the control soil samples. This is indicated by a statistically significant difference found between the concentration of analyzed elements in soils collected along Lagos–Badagry expressway and the control site. 相似文献
The aim of this study is to investigate the differences in the chemical conditions of lotic waterbodies in the two major ecosystems in Nigeria, the forest and savanna zones. The forest waters were slightly acidic (mean±SD pH = 6.72±0.58) while the savanna waters were slightly alkaline (pH = 7.11±0.33). The cationic order of dominance in the forest waters was Na+ > Ca2+ > Mg2+ > K+ in contrast to Ca2+ > Mg2+ > Na+ > K+ in savanna waters. The forest waters were chlorided (typical of coastal and/or marine waters) whereas the savanna waters were carbonated in nature, typical of the worldwide freshwater. Organic carbon was significantly higher in forest waters than in the savanna waters (p < 0.05) while nutrient compounds were significantly higher in savanna waters than in forest waters. The seasonal variation of the chemical parameters was generally more evident in savanna than in forest waters. The differences in water quality between the two major vegetation zones reflect the differences in the biogeochemical processes and nutrient cycling that characterise forest and savanna ecosystems. 相似文献
The health and environmental consciousness of waste tires has increased tremendously over the years. This has motivated efforts to develop secondary applications that will utilize tire when they reach the end of their life cycle and limit their disposal in landfills. Among the applications of waste tires which are discussed in this review, the use of rubber crumbs in artificial turf fields has gained worldwide attention and is increasing annually. However, there are serious concerns regarding chemicals that are used in the manufacturing process of tires, which ultimately end up in rubber crumbs. Chemicals such as polycyclic aromatic hydrocarbons (PAH) and heavy metals which are found in rubber crumbs have been identified as harmful to human health and the environment. This review paper is intended to highlight some of the methods which have been used to manage waste tire; it also looks at chemicals/materials used in tire compounding which are identified as possible carcinogenic.