Determination of Sulphur (IV) Oxide in Ilorin City, Nigeria, During Dry Season

Ambient concentrations of sulphur (IV) oxide (SO2) have been determined in the city of Ilorin, Nigeria between mid February and mid Novembers 2003. SO2 levels were found to vary significantly with the traffic density and human activities. There was a significant difference (P = 0.05) between the SO2 concentrations at two sites (high and low traffic volume areas); however, there was no significant difference (P= 0.05) between high traffic/medium population density and medium traffic/high population density areas. The regression analysis indicated a strong correlation (r= 0.94) between the concentration of SO2 pattern and the hourly average traffic volume in all the sites. Average level found for the city was 59.3 ± 1.9ppb, which falls within the limits of the United States Environmental Protection Agency guidelines for air quality standards. Atmospheric pollution being one of the most dominant problems associated with urbanization, urban areas are associated with high density of industries and transport networks, among other infrastructure, which generate a wide range of air pollutants .@JASE

Monitoring of sulfur dioxide in the guinea savanna zone of Nigeria: implications of the atmospheric photochemistry

The level of sulfur(IV) oxide (SO2) in the tropospheric environment of Ilorin is presented using three urban classes and a control site from 2003-2006 wet and dry seasons. The mean concentrations over the years during wet and dry seasons were 1.29 ± 0.17 and 7.17 ± 0.87 (ppb), respectively. The wet season concentration was 15.25% lower than the dry season due to rain attenuation. The mean values at the control site for two seasons were one order of magnitude lower than those in the urban sites. The overall average concentration over Ilorin city was 4.23 ± 0.52 ppb. The value is comparable with other cities of the world and is within the limit of the United State Environmental Protection Agency (USEPA) Guidelines for Air Quality Standards. SO2 levels were found to varied significantly with vehicular intensity, other anthropogenic activities also decreased drastically during wet season. There was a significant difference (p = 0.05) between SO2 concentration with high and low traffic flow count; however, there was no difference (p = 0.05) between high traffic/medium population and medium traffic/high population density areas. The regression analysis indicated a correlation between SO2 and the hourly traffic volume in almost all the sites

Carbon flow pattern in the forest zones of Nigeria as influenced by land use change

Forest in Nigeria plays a much wider role in the overall balance of issues affecting the country than those of climate change alone. Nigeria’s tropical forest is depleting fast, due largely to uncontrolled human activities. Poverty, urbanization, population growth and insecurity are the major causes of this trend. Tracking carbon flow in these forest life zones will help account for the effect of these activities on the environment. COPATH, an acronym for Total Carbon Flow from Conversion to Agriculture, Pasture, Harvest and OTHER land-uses including construction of dams, roads, forest fires and human settlement, etc., was used for tracking carbon flow in the forest zones. From the five forest life zones, total carbon stored was estimated to be 2.55 TgC. The four activities of agriculture, harvest, pasture and bush burning were pronounced in contributions to land use changes, particularly to forest depletion. In this paper it is shown that carbon emission was highest from harvesting activity in year 2000, principally from clear-cutting activity in the lowland rainforest as against that of 1990 study, which showed agricultural activity as the major anthropogenic activity leading to carbon release into the atmosphere. Further, it is shown that the value of carbon emission is on the increase as compared to the earlier study with 1990 as the base year. During the two periods of study, it was however, observed that the relative contribution of each of the activities that are responsible for deforestation and affects carbon flow pattern in the forest zones and invariably causes carbon emission had not changed. Though a look at the fractional contribution of each of these activities in 2000 as against that of 1990 estimates shows a marked change. The study also concludes that if there is no change in the estimated deforestation rate of 2.23% per annum of the forest formations, lowland rainforest and riparian forests are likely to disappear by 2040.Key words: Carbon flow pattern, forest life zone, land use, human activities, deforestation