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This research was conducted to analyze the soil physico-chemical properties of Shonga Irrigation Scheme to ascertain its suitability for rice production. The study was carried out in the dry season of 2019. Disturbed soil samples were collected from the 0–15 and 15–30 cm soil layers in five identified areas in the irrigation scheme. The samples were sent to the Soil laboratory of the Lower Niger River Basin for physical and chemical analysis. Most of the soils were strongly acidic to moderately acidic with pH values ranging between 4.8 and 5.7. The organic carbon and organic matter ranged from 0.13 to 0.19% and 0.03 and 0.32%, respectively which implies low fertility. Calcium values ranged between 2.1 and 3.75 cmol/kg, with the low values related to the soil pH status. Magnesium values averaged 2.48 and 1.95 cmol/kg in the top and lower soil layers, respectively. Exchangeable Acidity (EA) values ranged between 0.20 and 3.40 cmol/kg in the surface horizon and between 0.2 and 5.4 cmol/kg in the sub-surface horizons. Available phosphorus had an average of 40.05 and 23.14 ppm in the surface and sub surface soil layers, respectively. Analysis of variance techniques was used for significant differences within chemical properties. For all tests, a threshold of P=.05 was used to define statistical significance. Soil pH and available phosphorus were within the recommended land suitability requirement for rice cultivation. Organic carbon, organic matter, calcium and magnesium were not within the recommended range for rice production. Organic carbon and organic matter can be supplied through the incorporation of organic manure.

Eutrophication, salinization, hypoxia, and toxic algae, among other environmental damages are costly consequences of agricultural drainage water (ADW), and therefore poses a threat to ecological biodiversity, food security and agriculture sustainability. This work aimed to assess the adsorption efficiency of rice husk (RH) modified by chemical and thermal treatments for sulphate minimization from ADW. RH obtained from a local rice mill was washed in distilled water, oven-dried at 105 ˚C for 24 h, milled and sieved into 0.3–1.18 mm particle sizes. The optimum condition for carbonization was determined by varying the temperature- 200, 300 and 400 ˚C and time- 1, 1.5, and 2 h, respectively. The RH was activated by chemical (H3PO4 and ZnCl2) and thermal treatment. Batch experiments were carried out varying temperature (40-60 °C), adsorption time (15–140 min) and adsorbent dose (1 and 2 g) in an ADW with known sulphate concentration, 30 mg/L. The carbonization yield at 400, 300 and 200 ˚C varies within 18.91- 27.48%, 27.39- 32.82 % and 81.94- 95.75% respectively. It was observed that the percentage of carbon converted into silica increases with burning time; hence, the optimum temperature of 350 ˚C for 2 h was used for carbonization. Also, sulphate adsorption rate increased with contact time and dosage suggesting that the process is controlled by surface and pore diffusion. Based on the temperature study, adsorption was favourable at lower temperatures. H3PO4 and ZnCl2 treated adsorbents have similar removal efficiency; however, ZnCl2 treated adsorbent has a higher efficiency due to its ability to enhance the stability and mesoporosity of carbonaceous material. Modified RH is a potential adsorbent that could be of noble use in ADW quality minimization. However, the huge gap between literature studies and field application needs to be bridged by good extension services and appropriate policy.

Irrigation and mulching are important soil management practices for sustainable food productions. Different irrigation and mulching treatments could however affect soil hydrothermal properties and hence the soil productivity. This study evaluated the effect of drip irrigation interval and mulching type on selected hydrothermal properties of an Alfisol cropped with Cucumber (Cucumis sativus). A field experiment, laid out in a randomized complete block design (RCBD) with three replications, was conducted with split-plot arrangement having irrigation interval as the main-plot and mulching material as the sub-plot. Three irrigation intervals: two days per week (D2), four days per week (D4) and six days per week (D6); and two mulching materials: plastic (M1) and spear grass (Imperata cylindrica) (M2) were applied. There were nine (9) treatment combinations which gave a total of 27 plots. Soil physical properties of soil water content (SWC), bulk density (BD) and saturated hydraulic conductivity (Ksat) were monitored during the growing cycle. Thermal conductivity, resistivity, diffusivity and volumetric specific heat of the soil were measured. There was no significant difference in thermal conductivity, thermal resistivity, thermal diffusivity and volumetric specific heat, under the irrigation intervals. The cucumber yield under the mulch treatment was in the order of M1 > M2 > M3. The Cucumis sativus yield was highest under M1 and D4 (11629.63 kg/ha) and lowest in M3 and D2 (3362.22 kg/ha). The mulching treatment had significant effect on the soil temperature, SWC, BD and yield while the irrigation treatment had no significant effect on the soil properties considered.