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An index approach to heavy metal pollution assessment of Eme River, Umuahia, Nigeria
Get PDFRivers are subjected to various kinds of natural and anthropogenic activities among which, indiscriminate and illegal sand mining is a major factor. The heavy metal content of a Nigerian river was studied between December 2017 and November 2018 in 6 stations in relation to suitability for human consumption using pollution indices. The indices used were Heavy Metal Pollution Index (HPI) and Contamination Index (Cd). Eight metals were evaluated using standard methods and compared with Nigerian Drinking Water Quality Standard. Some metals like iron, cadmium and lead exceeded limits; manganese, chromium and nickel exceeded limits in the dry season in some stations while copper and zinc were all within limits. The dry season values were significantly (P<0.05) higher than the wet season values. NPI showed all the stations exceeded the threshold (100) especially stations 1, 4 – 6 while Cd showed that stations 3 and 2 had low and medium contamination potential risks respectively and stations 1, 4 – 6 had high contamination potential risk. The indices effectively captured the effect of the anthropogenic activities (sand mining, swimming, washing, etc) in the river and showed that the water quality was not suitable for human consumption
Study on Physico- Chemical Parameters and Structural Characterization of Soils in Pudukkottai District of Tamilnadu, India
Get PDFThe soil is the most important constituent to fulfilment of all the basic needs of human beings and also is an important component of our farming. The study was conducted with the main objective to investigate the soil samples of Pudukkottai district of Tamil Nadu for its physico-chemical analysis and structural characterization. The collected soil samples were analyzed for its pH, EC, Nitrogen, Phosphorus, Potassium, Zinc and Iron. Besides, the sample was characterized by FTIR studies for structural conformation. From the study the results revealed that the collected soil was red soil and its texture was sandy clay loam. The soil pH was 9.29 which was alkaline and the EC was 0.02 dSm-1. The available macro-nutrients as nitrogen, phosphorus and potassium for paddy field soil samples had 118, 11 and 160 kg/ha respectively. Micronutrients Nutrients also analyzed. FT-IR spectrum of soil was recorded spectrum of soil was shown the C-H deformation vibrations occur at 1402. The C=C Stretching vibrations occur at 1644 and the N-H Stretching vibrations occur at 2344. Management options to improve the soil fertility were discussed
Effects of planting density on the growth and forage yield of two varieties of millet (Pennisetum typhoides Burm. F.) grown in Ekpoma, Nigeria.
Get PDFA field study was carried out during the 2016 cropping season to determine the effect of planting density on the growth and yield performance of two varieties of millet at Ekpoma. Gero badeggi and Gero bida varieties were sown at three densities (111,111, 222,222 and 333,333 plants ha-1). The experiment was a 2 x 3 factorial scheme laid out in a randomized complete block design (RCBD) with three replicates. The result shows that planting density had no significant effect on the growth parameters measured. However, Gero badeggi planted at 111,111 plants ha-1had the tallest plants, highest number of leaves/plant and stem girth while Gero bida planted at 333,333 plants ha-1 gave the shortest plants, least number of leaves/plant and stem girth, respectively. There was no significant difference in flowering trait amongst densities, but the varieties differed markedly in days to 50% flowering. Increasing planting density significantly (P<0.05) increased the forage yield. However, crops sown at higher densities had higher forage yield than the low density. The differences in observed between varieties were significant in some of the studied characters and thus millet sown at 111,111 and 333,333 plants/ha is recommended for millet production in the area.Keywords: Millet, planting density, growth and forage yield
Process optimization of ultrasonication-assisted extraction to obtain antioxidant-rich extract from Spirulina platensis
Get PDFIn this study highlights on the optimization of extraction process parameters of total phenolic content and antioxidant activity from Spirulina platensis, through ultrasonication (probe) technology. Especially, optimization of ultrasonication parameters was carried out employing Box-Behnken Design (BBD) and response surface methodology. Alongside the three levels of extraction parameters i.e. solvent volume, extraction time and frequency have been fixed. As responses, the total yield of extract, total phenolic content and DPPH radical scavenging activity (IC50) of the extracts were determined. The variability of each response variable was determined by developing multiple linear regressions. The statistical analysis (ANOVA) of developed mathematical models allowed the prediction of the behaviour of the responses, as a function of the variables involved in the process. The optimized extraction conditions were obtained at 58.76 kHz frequency, 10 mL of solvent volume for 6 min. Simultaneously this extract exhibited the highest content of total phenolic content (30.89 mg GAE/g powder), IC50 for DPPH activity (151.27 µg/mL). The extract exhibited an important antioxidant i.e. caffeic acid, which was quantified as 660.72±41.05 µg/g of dry algal powder using HPLC. In spite of fact that, this study offers an alternative method for obtaining natural antioxidants from algae for food and pharmaceutical applications. Keywords: Microalgae; Probe sonication extraction; Total phenolic content; Antioxidant activit
Heavy metal contamination of Pleuronectiformes species from Sinop coasts of the Black Sea
Get PDFIn the Turkish Black Sea coasts fish is particularly consumed because of high protein supplies, essential amino acids, vitamin, and mineral content. Fish are exposed to contaminants such as heavy metals in polluted waters. The aims of the study are to determine heavy metals in Pleuronectiformes species from Sinop coasts of the Black Sea and determine the health risks due to the consumption of contaminated fish. Pleuronectiformes species Scophthalmus maximus (Linnaeus, 1758) belonging to Scophthalmidae family, Arnoglossus laterna (Walbaum, 1792) belonging to Bothidae family and Pegusa lascaris (Risso, 1810) belonging to Soleidae family were collected from Sinop coasts of the Black Sea in fishing season of 2016. Heavy metals (Hg, Cd, Pb, Cu and Zn) in edible tissues were determined by ICP-MS (Agilent 7700x). The limit values given by the international and national organizations did not exceed in the muscle tissues of turbot, Mediterranean scald fish and sand sole. Overall Zn was detected in higher concentrations in all species followed by Cu, Pb, Hg and Cd. The results obtained from the analyses of the maximum levels of the metals except Hg were found in turbot. The highest Hg (0.021±0.007 µg g-1 wet wt.) was found in sand sole. However, the high amounts of Cd, Pb, Cu and Zn in turbot were 0.011±0.004, 0.07±0.005,1.32±0.28 and 14±3 µg g-1 wet wt., respectively. The EDIs and EWIs of the metals were estimated taking into account the mean of metal in all fish samples and the mean consumption of fish per day/week for adults. These results are normally significantly lower than the recommended values of FAO/WHO. Estimated HIs of all the considered metals were below the value of 1, therefore the metals in fish samples do not toxic any apparent threat to the population and these fishes are healthy for consumption.Keywords: Scophthalmus maximus, Arnoglossus laterna, Pegusa lascaris, heavy metals, Black Se
Propuesta de flexibilización de postgrados en geomatica en la Univerdidad Distrital F. J. C.
Get PDFEn la Facultad de Ingeniería de la Universidad Distrital Francisco José de Caldas se ofrecen programas de pregrado y postgrado que no tienen una cohesión muy fuerte entre sí, lo que implica que un estudiante que desea completar su ciclo académico e investigativo hacia una maestría o doctorado, le toma 9 o 10 años en obtener si título de magister desde el inicio de su pregrado, o 15 años hasta obtener si título de doctorado. Se propone es este artículo una manera de articular los currículos de los programas de Ingeniería Catastral y Geodesia con la especialización de Sistemas de Información Geográfica, junto con la Maestría en Ciencias de la Información y las Comunicaciones y terminando con el Doctorado en Ingeniería, para que un estudiante pueda terminar desde su pregrado hasta el doctorado en un tiempo de 10 años, obteniendo su título de pregrado, magister y doctorado en los temas relacionados con la Geomática y la Ingeniería
Temporal Water Balance Analysis in Different Climatic Scenarios in Oyo State, Nigeria
Get PDFThe study was conducted to examine water availability in different climatic scenarios in Oyo State. The data used comprised of rainfall and temperature records. The spans of the data used vary from one station to the other: 38-year data for Ibadan and 37-year for Ogbomoso stations, both collected from NIMET Office, Ilorin while 11-year also collected from the Office of Oyo State Agricultural Development Programme (OYSADEP) Headquarters at Shaki were available for Shaki Station. Evapotranspiration data for the three stations were empirically generated while water balance model was computed using MATLAB R2007a version in order to determine the respective water availability and the regression analysis was used to determine rainfall trends. The results showed that rainfall amounts vary from year to year and also increasing trends in the three stations over the period examined. It was also discovered that in all the periods investigated across the stations, Ibadan has 81.58%, Shaki, 81.81% and Ogbomoso, 56.80% as wet years indicating that there is abundant water resources in Oyo State. It is recommended that strategies be put in place to exploit excess rainwater for various purposes especially by increasing the capacity of water reservoirs and dams across the State for development of pipe borne water network and also, for irrigation farming during dry spells. Further investigation is recommended on water balance and its implications for agricultural practice in the study area
Replacement value of African Bread Fruit Seed Meal (Treculia africana) for Maize on the Performance of Starter Broilers.
Get PDFAn experiment was conducted to see the effect of parboiled and varying levels of boiled African breadfruit seeds (ABS) fed to starter broilers. The starter broilers were assigned to six treatment groups (control, parboiled, 10, 20, 30 and 40 minutes boiled ABS) with each of the treatments replicated three times in a completely randomized design (CRD). The diets were formulated to be iso-nitrogenous (22% CP) and iso-caloric (2700 Kcal/kg ME). Water and feed were offered ad libitum. Results shows that all parameters at the performance of starter broilers fed varying levels of boiled ABS were significantly (P<0.05) different with most of the significant level favouring the treatment T4 which is boiling at 20 minutes. Inclusion of boiled ABS into the diet of starter broilers improved the performance of the birds. It could therefore be concluded that ABS can serve as alternative nutritive source of nutrition in the diet of starter broilers. Keywords: African breadfruit seeds, Maize, Performance, Starter Broilers, Replacement value
Incidence of Cercospora Leaf Spot Disease of Groundnut (Arachis hypogaea L.) As Influenced by Sowing Date in Makurdi, Benue state of Nigeria.
Get PDFLeaf spots of groundnut caused by Cercospora spp is one of the major economic production constraint militating against groundnut production in Nigeria. Field experiments were conducted during the 2011 and 2012 seasons at the Teaching and Research Farm of the Federal University of Agriculture, Makurdi Nigeria to assess the effect of sowing dates on the incidence of Cercospora leaf spot of groundnut The 2 x 4 x 3 factorial (2 groundnut varieties/ 4 sowing dates/ 3 replications) experiment was laid out in a Randomized Complete Block Design (RCBD) and replicated three times. Results indicated no significant effect of Cercoscora leaf spot on the two varieties in 2011 but in Ex-Dakar recorded a significantly (P < 0.05) higher leaf spot incidence compared Borno-Red variety. Sowing groundnut seeds in 14th June to 29th June recorded significantly higher (P < 0.0) leaf spot disease incidence compared with sowing groundnut seeds in May. Ex-Dakar variety recorded higher leaf defoliation compared with Borno-Red variety in 2012 and 2012 seasons. Results indicated that Borno-Red had a significantly (P < 0. 05) higher 100 seed weight in 2011, while Ex-Dakar recorded higher 100 seed weight in 2012. The results has proved that early sowing of groundnut in May can be employed as alternative strategy for the management of leaf spot disease of groundnut in Makurdi, NigeriaKey word: Groundnut, disease incidence, sowing date, leaf defoliation, leaf spot
Evaluation of range flora and fauna composition of a community forest in north-central Nigeria
Get PDFForest structure assessment is vital in ensuring environmental function such as habitat provision for biodiversity and soil conservation. This study was carried out to assess the flora and fauna composition of a community forest. The systematic line plot technique was used for the establishment of sampling plots for floristic survey of woody trees species and shrubs. Direct observation and in-depth interview was adopted to acquire information on fauna species in the forest. The abundance and diversity of flora and fauna species in the forest was analyzed. The results reviewed a total 18 species in 13 families were recorded for woody plants, 12 species in 9 families were recorded for shrubs, 7 species in 6 families were recorded for climber and 16 species in 8 families were recorded for herbaceous plants. Pseudocedrela kotschyi, Chromolaena odorata, Opilia celtidifolia and Desmodium adscendens were the most abundance species for both trees, shrubs, climbers and herbaceous species respectively. Forty one species of fauna species within the class mammalian, aves, and reptile were indicated. Bird species form the major component of the animal species in the forest. It is suggested that forest reserve be protected from resource exploitation through monitoring and conservation education