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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Predictability of Philip and Kostiakov Infiltration Models under Inceptisols in the Humid Forest Zone, Nigeria) ผู้เขียน: Effiom Oku, Ambrose Aiyelari สื่อสิ่งพิมพ์:pdf AbstractKnowledge of the infiltration of water into a soil is very important for efficient soil and water management and conservation, especially when the water supply is through rainfall. For efficient irrigation water management, once field infiltration values are constant and the curve established for a particular soil, it is possible to determine during irrigation how long it will take to infiltrate a certain amount of water. Ring infiltrometer measurements were carried out at 10 m intervals down a 5% Inceptisol toposequence of 100 m length in a humid forest in southern Nigeria. The aim was to determine the infiltration capacity of the soil with slope positions and to fit the infiltration data into the Philip and Kostiakov infiltration models in order to quantify the hydrological behavior of the soil and the ability of these models to predict infiltration into the Inceptisols of a humid forest. The nonlinear least square procedure was employed to determine the parameters of the models—namely, the transmissivity and sorptivity of Philip’s model and the initial infiltration and the index of soil sorptivity reflecting the rate of declining infiltration capacity of Kostiakov’s model. The results indicated that the initial infiltration and cumulative infiltration ranged from 2.0 to 7.50 cm min-1 and from 84.90 to 555.20 cm after 6 h of elapsed time, respectively. The coefficient of determination was near unity indicating the models were a good fit for data and could be used to predict infiltration for the studied soil. Transmissivity values ranged from 0.14 to 1.29, putting the soil conductivity class between ‘very slow’ and ‘slow’. Sorptivity was very high with values in the range 1.20 to 8.08. The index of sorptivity of soil ranged from 0.65 to 0.88 indicating fairly high soil sorptivity and the initial infiltration of Kostiakov’s model ranged from 0.03 to 1.09. Goodness of fit was used to compare the measured and predicted infiltration values and showed that 10% and 50% disparities existed for initial infiltration and 30% and 70% disparities for cumulative infiltration under Philip’s and Kostiakov’s models, respectively. It can be deduced that Philip’ s model was more suitable than Kostiakov’s model for predicting water infiltration in Inceptisols of the humid forest zone of Nigeria. |
 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Socio-economic Factors Influencing the Output of Small-Scale Maize Farmers in Abuja, Nigeria) ผู้เขียน:Julius Ajah, Job N. Nmadu สื่อสิ่งพิมพ์:pdf AbstractNigeria is one of the developing countries facing shortages of cereal crops like maize. Based on this, research on the socio-economic factors influencing small-scale maize farmers? output was conducted in Abuja. A multi-stage sampling technique and semi-structured questionnaire were used for data collection. A total of 160 maize farmers were interviewed in four agricultural zones (40 from each zone). Data were analyzed using multiple regression analysis and descriptive statistics. The results showed that the land area cultivated, land rent, quantity of fertilizer applied, years of farming experience and household size were the major socioeconomic factors that significantly (p < .05) influenced maize output. The R2 value of 0.31 (adjusted R2 = 0.26) indicated that the variables accounted for 31 percent of the variation in maize output. The mean outputs of maize per hectare and per farmer were 316.73 kg and 614.56 kg, respectively. Socio-economic results showed that the mean age of the farmers was 39 years with a substantial percentage (68.12%) of them having, at most, primary school education. Based on the results, it was recommended that farmers in the study area should be informed through extension services of the socio-economic factors that influence maize output so that the farmers can consider these factors in their production decision making process. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Profitability and Resource Use Efficiency of Poultry Egg Production in Abuja, Nigeria) ผู้เขียน:Nmadu, J.N., Ogidan, I.O., Omolehin, R.A. สื่อสิ่งพิมพ์:pdf AbstractThe profitability, break-even point, elasticity of production, and resource use efficiency of poultry egg production by poultry egg farmers was determined in Abuja. Primary data were collected from 62 farmers drawn from the area of study by a simple random sampling technique. Analysis of data was carried out via the use of descriptive statistics, multiple regression, costs and returns analysis (budgeting), and break-even analysis. The costs and returns analysis indicated that an average farmer invested annually NGN (Nigerian naira currency) 3,504,352 (USD 1 is approximately NGN 160) in poultry egg production. The gross margin, net income, and gross return invested were NGN 10,875,663, NGN 9,798,772 and 1.72 respectively. These figures suggest that egg production in the study area was profitable. The study also showed that the break-even point for an average poultry egg farmer in Abuja was 3,978 crates of eggs per annum and the margin of safety ratio was 89 percent. In addition, the results of the study revealed that poultry egg farmers had positive, decreasing returns to scale (0.508) in egg production which indicated that poultry egg production was in the rational stage of production (Stage 2). Poultry production was profitable in Abuja but the farmers were not fully efficient in the use of their resources. To improve the profitability and resource use efficiency of poultry production, it was recommended that poultry egg farmers should implement better management practices to minimize the incidence of disease outbreaks, thereby reducing the cost of production. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Studies on Fungal Load, Total Afl atoxins and Ochratoxin A Contents of Gamma-irradiated and non-irradiated Sesamum indicum Grains from Abuja Markets, Nigeria) ผู้เขียน:Emmanuel Chukuma Akueche, Samuel Toba Anjorin, Basene Iyenebowa Harcourt, Doris Kana, Esther Adeboye, Isah Shehu, Rebecca Akande, Adekunle Temitope Adeleke, Owotayo Abiodun Shonowo, Charles Adedokun Adesanmi สื่อสิ่งพิมพ์:pdf AbstractThe fungal load, total afl atoxins (B1, B2, G1 and G2) and ochratoxin A (OTA) contamination of 36 samples of Sesamum indicum L. grains from Abaji, Gwagwalada, Kubwa and Karu in the Federal Capital Territory, Abuja, Nigeria were investigated. A total of 135 fungal isolates belonging to fi ve genera—namely, Aspergillus, Curvularia, Penicillium, Fusarium and Ascochyta—in decreasing order of prevalence were isolated from the non-irradiated grains. Only 34 isolates were obtained from the irradiated seeds at 3 kGy. Aspergillus spp. were observed in all the non-irradiated grain samples. Some fungal species were observed in irradiated grains treated with 3 kGy but none in the grains irradiated with 6–15 kGy. There was no consistent and no signifi cant (P > 0.05) reduction in the total afl atoxins and ochratoxin A contents of irradiated samples from the four markets at 3 to 12 kGy. However, all the sesame grains exposed to irradiation at 15 kGy had comparatively the least total afl atoxins and ochratoxin A contents. Multiple mycotoxin analysis and the nutritional quality of the irradiated mold-free grains should be further investigated. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Small-Scale Maize Farmers? Access to Farm Inputs in Abuja, Nigeria) ผู้เขียน:Julius Ajah, Job N. Nmadu สื่อสิ่งพิมพ์:pdf AbstractThe study evaluated small-scale maize farmers? access to farm inputs in Abuja, Nigeria because one of the most limiting factors in the development of agriculture in Nigeria is inadequate access to farm inputs. To cover the study area, a multi-stage sampling technique was adopted while structured questionnaires were used for data collection. A total of 160 maize farmers were interviewed in four agricultural zones (40 farmers from each zone). Data were analysed using mixed factorial analysis of variance; mean separation was carried out at the 5 percent probability level. The results showed that maize farmers? access to the different types of farm input differed significantly (p < .05). Of all the farm inputs, land was the most accessible with a mean access value of 3.03 while the least accessible farm inputs were tractor services (0.64) and loans (0.58). Furthermore, the location of the farmers in Abuja had a significant (p < .05) interaction effect on farmers? access to farm inputs. On the contrary, there were no significant differences (p > .05) in the mean responses of the maize farmers? in the four different agricultural zones with respect to access to farm inputs. Generally, the grand mean access value (1.73) indicated that the maize farmers had poor access to all the farm inputs. Based on the grand mean access value, it was concluded that access to the farm inputs was poor; hence it was recommended that Input and Farm Information Service Centres should be established under a publicprivate partnership to increase farmers? access to inputs, especially the most limiting inputs. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Runoff and Soil Loss of Vegetative Fallow and Farmland of South-Eastern Nigeria) ผู้เขียน:Iwara, A.I. สื่อสิ่งพิมพ์:pdf AbstractThe effects of two different land uses—namely, 10 year-old vegetation fallow land and farmland—on soil erosion and soil loss were investigated in a part of the rainforest zone of Nigeria. Measurements of 61 sites where rainfall had produced runoff and 54 sites where rainfall had generated soil erosion were carried out from March to November in the 2012 rainy season. The average runoff amounts for the 10 yr-old and farmland plots were 0.11 mm and 0.41 mm, respectively. The average soil loss for the 10 yr-old vegetation fallow land and farmland plots was 12.43 kg.ha-1 and 127.68 kg.ha-1, respectively. The differences in runoff and soil loss between the treatments were highly signifi cant (P < 0.001). The study showed that soil erosion had occurred on the 10 yr-old vegetation fallow plot even with greater aerial coverage conditions resulting in the loss of nutrient-rich topsoil, though the plot had signifi cantly reduced runoff and soil loss compared with the farmland plot. The signifi cant reduction in soil loss with increasing rainfall events on the 10 yr-old plot was indicative of the importance of vegetation in promoting good hydrological functioning in the area. The fi nding from the statistical analyses identifi ed rainfall as the principal cause of losses on the 10 yr-old fallow plot, while on the farmland, rainfall and tree girth were the main causes of soil erosion. The continuous loss of nutrient-rich topsoil, if not checked, may affect the ability of the degraded soil to replenish lost nutrient for subsequent farming. However, to reduce the rate of losses of both runoff and soil on cultivated farmlands, all trees should not be cut down during farming operations as is practiced in this part of the world. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Variability in Soil Properties Along an Udalf Toposequence in the Humid Forest Zone of Nigeria) ผู้เขียน:Effiom Oku, Ayuk Essoka, Eunice Thomas สื่อสิ่งพิมพ์:pdf AbstractUniform soil management without any knowledge of the variability of soil properties could result in some parts of an agricultural field receiving insufficient inputs, while other parts receive an excess. Profile soil samples were collected and analyzed for some physico-chemical properties along an Udalf toposequence and their variability assessed. Soil pH was consistently least variable along the toposequence and at all depths. Highly variable properties on the upper slope (crest) included Ca, Mg, Na, K, and P; on the middle slope (hill slope) they were K, organic C, N, silt and clay; and on the foot slope (valley floor) they were Mg, organic C, available P, EA, silt and clay. Moderately variable properties were: C. electrical conductivity (EC), effective cation exchange capacity (ECEC), bulk density, clay, gravimetric moisture, volume wetness and degree of saturation on the upper slope; Mg, Na, EC, and ECEC, base saturation, sand, bulk density, gravimetric moisture and volume wetness on the middle slope; and on the foot slope Ca, N, EC, ECEC, base saturation, bulk density, gravimetric moisture, volume wetness and degree of saturation were moderately variable. The use of bulk samples randomly collected to determine soil properties should be minimized. Large soil sample sizes are needed for soil property studies along the toposequence, as most properties varied from highly to moderately variable. Uniform soil management along the toposequence should be avoided. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Economic Analysis and Constraints of Traditional Processing of African Locust Bean in Kwara State, Nigeria) ผู้เขียน:Rashid Solagberu Adisa, Simeon Olushola Ayanshina สื่อสิ่งพิมพ์:pdf AbstractThe African locust bean (Parkia biglobosa) is mostly a wild-growing crop-tree whose fruit possesses widespread food and nonfood usefulness throughout West Africa. In Nigeria, the processing of African locust bean seeds (ALBS) into a soup condiment is a source of income among many rural households. Incidentally, ALBS processors are somewhat associated with poverty despite the widespread demand for the product. This study examined the economics and constraints of ALBS processing, with a view to identifying the interventional imperatives. The study was conducted in late 2011 in Kogi State, Nigeria—well known for the production of ALBS condiments. A systematic random sampling technique was used to select 139 respondents from a list of processors compiled with the assistance of leaders of the typically informal associations of ALBS processors. A structured questionnaire was used to collect data, while a reconnaissance survey of the study area was also conducted. A test-retest method was used to determine the reliability of the questionnaire, yielding a coefficient r value of .89, implying that the instrument was reliable. The results revealed that ALBS processing was dominated by middle-aged women, having little or no formal education, and mainly using labor-intensive traditional techniques. Cost-benefit analysis however revealed a relatively high profit margin. Regression analysis revealed that the cost of seeds, labor and water availability contributed most significantly to the output of ALBS processing among respondents. Major production constraints were ALB tree felling/burning, low technology application, and storage. The study recommended, inter alia, development of appropriate ALBS processing technology (such as a de-pulping machine) and virile extension and credit intervention. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Green Structure for Soil and Water Conservation on Cultivated Steep Land) ผู้เขียน:Effiom Oku, Ambrose Aiyelari, Paul Truong สื่อสิ่งพิมพ์:pdf AbstractA study was conducted on a farmer’s field on a 35 % slope in the humid forest zone, Nigeria on the use of a green structure that performed some engineering functions on cultivated steep lands to help curtail soil and water losses. Treatments consisted of a vetiver grass strip as a green buffer structure at different surface spacings of 5, 15, 25 m with no vetiver as the control and were laid out in a randomized complete block design with three blocks. Twelve erosion plots each measuring 50 m long and 3 m wide were used for the study. The plots were planted with cassava and maize in a simple crop mixture. The runoff, soil loss and crop yield were assessed under the four treatments. The rainfall lost as runoff with no vetiver (control plot) was 24.8 % compared to 7.7, 11.5 and 11.6% lost on the green structure plots at spacings of 5, 15 and 25 m, respectively. Soil loss on the no vetiver plot was 40 times higher than the acceptable soil loss limit of 12 t.ha-1 yr-1 for the tropics, whereas the soil loss on plots under vetiver at spacings of 5, 15 and 25 m was 1.4, 6.8 and 6.5 times higher than the acceptable limit. The maize grain yield and the fresh cassava tuber yield were significantly lower in the control plots and highest with the 5 m spacing. A vetiver strip as a green structure was more effective at a spacing of 5 m as it reduced soil and water losses and increased crop yield. This spacing was also adequate for traditional pre- and post-farming activities. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of Age of Rubber (Hevea brasiliensis Muell Arg.) Plantation on pH, Organic Carbon, Organic Matter, Nitrogen and Micronutrient Status of Ultisols in the Humid Forest ผู้เขียน:Effi om Oku, Anthony Iwara, Ekaette Ekukinam สื่อสิ่งพิมพ์:pdf AbstractMicronutrients are required by plants in minute quantities. Literature on the micronutrient status of soils sustaining rubber plantations in the humid forest zone of southern Nigeria is not readily available where a study was carried out on Ultisols to examine the status of manganese (Mn), iron (Fe), Copper (Cu) and zinc (Zn) in rubber plantations aged 7, 16, 39 and 41 yr. A grid sampling method was used to collect soil samples from fi ve quadrats of 10 m ? 10 m in each of the plantation plots. For each plot, fi ve surface (0–15cm) soil samples were randomly collected and composited. The soil samples were analyzed for pH, organic carbon (OC), organic matter (OM), nitrogen (N), Mn, Fe, Cu and Zn. Data were analyzed using analysis of variance and Pearson’s correlation. The soils were strongly acidic (pH 4.0–4.4). The OC status was rated as very low (below 2%) in all the plantation soils. In addition, the OM was rated as low under the trees at 7, 16, and 39 yr whereas, for the 41 year-old plantation, it was rated as high. The Mn and Zn contents were rated as low for the 16, 39 and 41 year-old rubber plantations, whereas they were rated as medium under the 7 year-old rubber plantation. The Mn, Fe and Cu contents varied signifi cantly (P < 0.01 to P < 0.05) with the age of trees, while Zn did not vary (P > 0.05) among the rubber plots. The fertility rating of Fe was toxic or excessive in all the plantations and the levels of Cu were rated high. The results showed that the contents of Zn, Fe, Cu and Mn in the soils decreased with increasing age of rubber plantation. The Mn content was rated as high, medium, medium and low in the 7, 16, 39 and 41 year-old plantations, respectively. The Fe contents were rated as high whereas the Cu contents were rated as medium. With the exception of the 7 year-old plantation, where Zn was rated as medium, the Zn contents were below the critical limits for crop production, with soils in the 16, 39 and 41 year-old rubber plantations benefi ting from its application. The low values of soil pH across the rubber plantation plots did not signifi cantly favour the increase in selected micronutrient levels in the soil. To improve the levels of micronutrients in the rubber plots, it is recommended that biomass burning should be discouraged during replanting as it strips the soil of these nutrients. The use of organo-mineral fertilizer combined with inorganic fertilizers is recommended. Care must be taken not to apply Mn in excess. A rubber-based agroforestry system, as opposed to rubber monocultures is recommended as it would improve the micronutrient levels of the soils in the plantation. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Evaluation of Vetiver Grass Buffer Strips and Organomineral Fertilization for the Improvement of Soil Physical Properties) ผู้เขียน:Effiom Oku, Olajire Fagbola, Paul Truong สื่อสิ่งพิมพ์:pdf AbstractSoil erosion still remains the major cause of deterioration of soil physical qualities on cultivated lands worldwide. A study was carried out on erosion plots at the Teaching and Research Farm of the University of Ibadan, Nigeria to assess soil physical properties after five years of using vetiver grass buffer strips (VGBS) and organomineral fertilizer (OMF) with bare soil on which farmers had planted without soil conservation measures as the control. Samples were analyzed for water stable aggregates (WSA), mean weight diameter (MWD), bulk density, porosity and particle size distribution. The cone index (CI) was also assessed. Infiltration values were fitted to Philip’s and Kostiakov’s models. Results showed that the amount of WSA for the VGBS and OMF plots was the same (64%) and on the bare soil was 54%. The MWD on the VGBS plot was 6.11% higher than on the OMF plot and 19% higher than on bare soil. The bulk density for the bare soil was 4% higher than that of the VGBS plot. Porosity values for the VGBS and OMF plots were the same, being 8% higher than the bare soil plot. The CI was 15.7% and 7% lower on the VGBS and OMF plots, respectively, compared to the bare soil. Cumulative and initial one-minute infiltration increased by 39.4% and 35%, respectively, on the VGBS plot when compared with the bare soil. Hydraulic conductivity increased by 41.7% on the VGBS plot when compared with bare soil. The initial capacity of the soil to accept water increased on the VGBS plot by 19% over the OMF plot and 39% over the bare soil plot. The index of soil sorptivity (reflecting rate of decline of infiltration capacity) was the same for the VGBS and OMF plots and 21.78% higher than for the bare soil plot. The use of vetiver grass buffer strips on erosion-prone cultivated fields over the years could act as a source of organic fertilizer, improving soil physical properties. |
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