DEPARTMENT OF SOIL SCIENCE AND LAND MANAGEMENT

The study was carried out at Iguzama Community in Ovia North East Local Government area of Edo state, Nigeria, to evaluate some soils for tomato cultivation. The study area consisted of two sites; Site A, a 4 hectare land, and site B, a 12 hectare land. Soil survey was carried out by the rigid grid method at a detailed scale, using the rigid grid method which produced four mapping units. Each mapping units was represented by a pedon and each pedon was appropriately described. Soil samples were analysed using standard procedures. The result of the land evaluation revealed that pedon 1a (1.65ha) representing 38%, pedon 2a (2.64ha) which representing 62%, pedon 1b (6.4ha) representing 53% and pedon 2b (5.69ha) representing 47% of the study area were not suitable (N) for tomato cultivation due to severe limitations in soil physical characteristics and fertility. Limitations in soil physical characteristics cannot be amended, thus the study area should not be used for tomato cultivation; however, the study area may be used for other purpose(s) for which it is found suitable.

The study was carried out at the Experimental Field of the Department of Soil Science and Land Management, Faculty of Agriculture, University of Benin, Benin City (latitude 6.4013754° and 5.6258° North and longitude 5.625880° and 6.40127231 East). The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications, four treatment levels with different rates of NPK 20:10:10 (0, 150, 300 and 450kg/ha). Planting was done in October at 0.5m x 0.5m spacing. The study was carried out to determine the effect of NPK 20:10:10 fertilizers as soil amendment for the growth and development of fluted pumpkin in a degraded ultisol. Experimental trials were conducted and the following growth and yield parameters were
collected: Vine length and number of leaves. The experiment was terminated 8 weeks after planting and soil samples were collected for laboratory analysis. Soil physical and chemical properties such as Particle Size Distribution, Textural Classification, Soil Organic Carbon, Total Organic Nitrogen, Available Phosphorus, Exchangeable Bases (Ca, Mg, Na, K), Cation Exchange Capacity and Exchangeable Acidity were determined.

This field experiment was conducted in the Experimental Field of Faculty of Agriculture, University of Benin, Benin City, to ascertain the physical and chemical properties of soil and agronomic performance of Kidney bean (Phaseolus vulgaris) and Maize (Zea Mays) in monoculture and intercrop. The experiment was laid out in a randomized complete block design (RCBD) with three levels of treatment and three replicates. Soil samples were
collected before and after experiment for determination of parameters: pH, total organic carbon (TOC), total nitrogen (TN), available phosphorus, potassium, calcium, magnesium, sodium, hydrogen, aluminium, sand, silt and clay. Also plant parameters like, stem girth, number of leaves, vine length, weight of 100 grains and yield were also determined. Data collected were subjected to analysis of variance and Duncan Multiple Range Test was used
to separate means at 5% level of significance. Results show that the total nitrogen content of the soil in the sole maize plot reduced to 0.54 g/kg from the 0.63 g/kg recorded in the soil before sowing while the kidney bean + maize intercrop plot increased to 0.73 g/kg and the
sole kidney bean pot was 0.80 g/kg. Furthermore, the soils in the area were generally acidic in nature and belong to the loamy sand textural class. The effect of intercropping on yield varied between kidney bean and maize. For kidney bean and intercropping, there was a
slight increase in grain weight (32.8 g under intercropping compared to 31.9g in monoculture) and a minor improvement in total yield (0.72 t/ha in intercropping relative to 0.70 t/ha in monocropping). This suggests that intercropping had positive effect on yield of
kidney bean. The nutrient (nitrogen, phosphorus, potassium, calcium and magnesium) content of the grains of maize and kidney bean were not affected by intercropping. However, intercropping resulted in a decrease in yield components (stem girth, number of leaves, plant
height, weight of 100 grains average weight of cob and grain yield) of maize while kidney bean recorded increment in growth and yield parameters.

This study investigated the response of soil fungi to various organic amendments; earthworm cast (EC), poultry manure (PM), and inorganic fertiliser (urea) and their impact on the growth of amaranth (Amaranthus cruentus L. The experiment aimed to bridge the knowledge gap regarding the effects of organic amendments on fungal communities and their potential benefits for sustainable amaranth production. The experiment was done using a complete randomised design (CRD) and replicated three times, using soil and a plastic container. Results showed that organic amendments significantly influenced the composition of soil fungal communities compared to the control treatment. Notably, Trichoderma spp., a fungus with high phosphate solubilization potential, was most abundant in urea-amended soil. However, poultry manure (PM) treatment yielded plants with the highest fresh and dry matter weight, likely due to increased nutrient availability and microbial activity stimulated by the breakdown of organic matter. The study showed that PM amendments improved soil health, promoting the growth of beneficial fungi like Trichoderma spp., and enhancing amaranth growth, potentially contributing to sustainable agricultural practices

Phosphorus (P) is one of the essential macronutrients needed for plant growth but its use efficiency is reduced due to adsorption sometimes caused by influence of pH. The study aimed at
determining the chemical and physical properties of the sampled soil as well as P sorption capacity at different pH in kulfo soil series of Nigeria Institute for Oil Palm Research (NIFOR), Benin city, Edo state. The study was conducted on twelve (12) samples collected from four (4) soil depths (0-30, 30-60, 60-90, and 90-120 cm) in four (4) replicates from the Kulfo soil series. Physical and chemical properties were determined following standard procedures while the P sorption capacity were determined by equilibrating 5 g soil for 24 hours in 25 ml of P retention solution containing 1000 mg P/L as KH2PO4. The P in the soil P retention suspension was read using the Nitric vanadomolybdate yellow method. The amounts of P adsorbed were calculated by plotting a graph of absorbency against % p retention (100, 80, 60, 40, 20 and 0%) of the standard serial solution. Afterward, P retention of the samples were determined from the regression equation of the curve. The data obtained were subjected to statistical analysis using Genstat statistical package. The means were separated at 5% level of probability using Duncan multiple range test. The physical properties indicated that the soil's textural class was predominantly sandy loam for all depths, except at 0-30 cm, where it was Loamy Sand. The chemical properties of the soils revealed that they were acidic, with a mean pH value of 4.71. Other soil properties such as K, Ca, Mg and Na were within the normal range of crop production. The % p sorption varied with soil depths at all pH level, the % P retention at pH (3.0, 4.6, 7.0 and 8.6) had a mean value of (23.5, 19.0, 13.85 and 14.15) respectively. The influence of pH on P sorption calls for a compressive P management approach for the soil, designing the best P management practice to reduce P sorption in soil.

This study was carefullycarried out in Iguzama commity in Ovia North East Local Government. Area of Edo State, to evaluate some soils for African Native Pear cultivation. Soil survey process was carried out on the site using the rigid grid method at a detailed scale. The survey produced four mapping units and each represented with a pedon. Soil samples were collected from each of the pedon for analysis in the laboratory using standard procedures. Soil survey process was carried out by the grid method at a detailed scale which produced four (4) mapping units. Each mapping units was represented by a pedon and each pedon was appropriately described according to FAO (1976). Soil samples were analysed using standard procedures. Result in all the Pedons shows that mean value for Sand ranges from 787.00-924.00, while Silt ranges from 15.00-44.00 and Clay ranges from 88.00-190.00. Mean value for pH ranges from 5.24-6.38. Sand recorded low variation in all the pedons with cv values ranging from 5.10 to 91.50%; Silt ranges from 8.37 to 54.20% and clay ranges 32.20 to 95.70%. Results of Suitability evaluation showed that pedons 1A and 2A representing an area 3.3 hectares and amounting to 55 % of the land area were marginally suitabale (S3) for African Native Pear cultivation with limitation in climate as a result of rainfall and length of growing season while pedons 1B and 2B representing an area of 3.3 hectares and amounting to 55 % were moderately suitable for African Native Pear cultivation with limitation in soil fertility as a result of the pH of the soils.Thus, the cultivation of African Native Pear in the study area could be profitable after amelioration, it is therefore recommended that the land should be adequately maximized for African Pear cultivaton since the risk of failure is at minimal level.

This study examined the forms and distribution of nitrogen in selected domestic dumpsites
in Ughelli Metropolis, Delta State. Soil samples were collected using the soil auger from three different sample locations in Ughelli Metropolis, Ughelli North Local Government Area Delta State. The soils were analyzed for some chemical and physical physical properties determined include the soil textural classes such as sands, clays, and silts. Some chemical properties studied in this experiment included pH, Total Nitrogen, Organic Nitrogen, Inorganic Nitrogen, Exchangeable Cations, Available Phosphorus, Organic Carbon, and Organic Matter. The results show that the predominant textural class was sand, with varying proportions of sand, silt, and clay. Sites 1, 2, and 3 had material compositions, with total sand dominance in the topsoils and increasing clay contents at increasing soil depths (30 - 60 cm). pH values ranged from 6.40 to 5.79 with mean value (6.10), 6.11 to 5.57 with a mean (5.18), and 6.61 to 5.63 with a mean (6.12) in Sites 1, 2 and 3 respectively. Organic carbon content was highest in topsoils (0 - 30cm) across all sites while total nitrogen exhibited variations across soil depths with high amounts in the topsoils (0 -30cm). Available phosphorus content decreased down soil depths, while exchangeable cations showed soil depth-related trends. The presence of exchangeable cation decreased with depth. However, there was little or no changes in the contents of Magnesium and Potassium at 30-60cm depth across sites 2 and 3. Exchangeable Acidity was found to increase with increasing depth across the various sites. Organic and Inorganic Nitrogen contents were found to decrease with increasing depth across the various selected dumpsite in Ughelli Metropolis Delta State. In general, both organic and inorganic nitrogen in the selected domestic dumpsite were found to correlate positively with some soil physical and chemical properties. The experiment shows that dumpsite nitrogen contents of the study areas were greatly influenced by type of waste materials, presence of leachate, surrounding groundwater and environmental conditions.

This project was a detailed investigation on the properties of subgrade soils used in the construction of Warri-Sapele road in South South, Nigeria. Subgrade samples were collected at nine (9) different spot by doing auger borings examinations on the spots that are observed to have failed or are failing at about 5 and 10 meters away from the tarred road at one side. The samples were subjected to the following laboratory tests; Compaction test, California bearing ratio (CBR). According to O'Flaherty the range of value anticipated using standard proctor test method are MDD and OMC which range from 1.72g/cm3 to 1.84g/cm3 and 8.88% to 12.70% respectively, therefore the results indicated that all the samples were sandy clay in texture. The CBR values for the top unsoaked and soaked samples of the subgrade soil range from 21.9% to 37.5% and 5.0% to 26.1% respectively while bottom unsoaked and soaked range from 17.9% to 51.5% and 9.3% ((P2R3, Sapele) to 37.3% respectively. Therefore, the CBR test results obtained conform to the Federal Ministry of Works and Housing which confirmed that the subgrade sample materials are suitable for road construction except for subgrade materials P2R3 collected from Sapele which however can be stabilized to meet the standard requirement before being used .These data obtained from the analysis can be useful by civil engineers in the design and construction of the study area for maximum durability.