Geography- Scholarly Publications

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Browsing Geography- Scholarly Publications by Subject "assessment"

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  • Item
    Open Access
    Seasonal Assessment of Physico-chemical Concentration of Polluted Urban River: A Case of Ala River in Southwestern Nigeria
    (Academic Journals Inc., 2011) Ayeni, A.O.; Balogun, I.I.; Soneye, A.S.O.
    This study assessed the seasonal surface water quality of River Ala upstream Akure Nigeria This was necessitated by the peoples’ consideration of water from rivers as substitute to the reigning incidence of water shortage in the downstream of the river. Six locations were chosen spatially within the urban built-up to reflect a consideration of all possible human activities that are capable of changing the quality of river water. Water samples were collected for a period of 12 months. The water samples collected were analyzed for physic-chemical parameters which include pH, total dissolved solids, dissolved oxygen. biochemical oxygen demand, total hardness, calcium magnesium, chlorine, nitrate, iron and zinc using standard procedures. For spatial reference the location of sampling points was determined with GPS and interpolated on digitized topographical map sheets of the study area. The observed results of the laboratory analysis were then presented, described and compared descriptively with the international standards for drinking water. It was observed that variation exist in the quality of the sampled waters and impaired to different degrees using WHO drinking water standards for the selected parameters. The results of the correlation coefficient shows that inverse direct relationship exist between some parameters for instance, there is inverse relationship between pH and DO at 95% confidence level during the rainy season while Ca+ has direct relationship with Mg and C- 95%. Therefore, considering the level of impairments of Ala River in Akure-Nigeria, water is unsafe for domestic purposes and it continuous use prognosticate health danger to the residents.
  • Item
    Open Access
    Soil Textural Mapping: A Pathway for Sustaining Urban Agriculture in Metropolitan Lagos
    (Enproct Consultants Ltd, Lagos, 2012) Ayeni, A.O.; Adedayo, V.T.
    Soil texture is one of the important factors for determining crop yields and information about agricultural viability in any geographical location. For instance, soil fertilization, soil treatment and irrigation designs as well as power requirements for farm machinery require detailed information on soil texture. This paper thus examines soil textural classes in selected urban farming areas of metropolitan Lagos, namely Tejuoso, Alapere, Festac, Barracks, Oko-Oba and Idi-Araba farm communities. It further relates the textural classifications to the cultivation and production of vegetables. Soil samples for textural analysis were collected from 6 selected locations and in each location, 5 samples at 0-15 and 15-30 cm depths were taken using composite sampling techniques. Determinations of textural classes were done in the laboratory using the mechanical analysis method with the aid of hydrometer to calculate the percentage of sand, silt, and clay in the sampled soils. The production of soil texture map was done through remotely sensed data processing. Acquired soil base map was scanned, Geo-referenced and digitized to extract the soil type layers. Updating and superimposing of attribute information of textural classification were done through interactive techniques using Microsoft excel 2007 and Arc Info version 9.2. The finding shows that the soil textural fractions (% sand, % silt, and % clay) were spatially observed, nevertheless, only one quarter of textural classes are represented in the selected area. The regression model (R2) result generated denote P > 0.391, P > 0.100 and P > 0.529 for % sand, % clay and % silt respectively. The application of animal feed manure was noted to have contributed to high silts contents in agricultural land of urban Lagos especially around Tejuosho and Alapere areas. Litter decomposition and soil water pressure also accounted for the variability but the effect was not consistent across different soils (P < 0.06). The output of the interactive techniques also reveals that there is similarity between laboratory result and the soil map used as baseline information. Interview however reveals that farmers lack knowledge of soil map and textural classes. The study therefore recommends that for soil fertility sustainability in the urban areas of Lagos, farmers need to be enlightened on soil map, textural classes and manure application through effective education awareness.