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The field study was carried out on a sandy clay loam forest ochrosol at Hodzo, near Ho in Ghana, from July 2017 to May 2018. The objective was to determine how tillage and weed control techniques affect the physical properties of the soil. The split-plot design was used in the study, with tillage serving as the main factor and weed control serving as the subplot factor. The tillage treatments were no tillage (NT), minimum tillage (MT), and ploughing followed by harrowing and ridging (PHR) and deep tillage followed by Ploughing, harrowing, and ridging (DPHR). On the other hand, the weed control treatments comprised hoe weeding, machete weeding, and no weeding. It was realised during the study that, in the upper layer (0–15 cm), the PHR treatment produced lower soil penetration resistance (38.57 kPa), high dry bulk density (1.019 Mgm−3), and slightly lower soil moisture content (5.0%) in comparison with the other tillage treatments at three months after planting (3 MAP). The results on initial and basic infiltration rates portrayed a trend where the more intensive the tillage regime (hence, soil disturbance), the lower the initial and basic infiltration rates, and vice versa. Moreover, tillage had a higher impact on the physical characteristics of the soil than weed control methods. Nonetheless, tillage with machete weeding resulted in lower soil dry bulk density and higher moisture content, while tillage with hoe weeding reduced penetration resistance and increased infiltration rates. Given similar weather and soil conditions, the study recommends that farms and farmers in the Ho Municipality and the Volta Region adopt conservative tillage methods such as heaping with machete or hoe weeding and use the savings to expand their farm sizes. Therefore, the adoption of conservation tillage practices is more crucial than ever in order to ensure sustainable food production with minimal impact on the soil and environment.

The objective of this research was to design, construct and evaluate a variable chipping clearance cassava chipper for processors which will produce uniform and varying cassava chip geometry for multipurpose usage. It consists of a drive shaft with varying chipping clearances (6, 18, and 28 mm) to produce varied chip geometry. The average throughput capacity of the chipper was found to be 475.5 kg·h^–1 at a speed range of 460–800 rpm with a chipping clearance of 6–28 mm. The average chipping efficiency ranges from a minimum–maximum of 76.6–99.4% for the selected operational speeds and chipping clearances. The chipping capacity and the output to input ratio is dependent on the operational speeds and chipping clearances of the machine.

Most cassava chipping machines adopt the fixed chipping clearance at different speeds accounting for inconsistencies in chip geometries. These irregularities influence drying time and may cause fermentation, culminating in poor quality and safety of dried chips. The need to develop a variable chipping machine capable of producing varied chip sizes for different uses necessitated this research. The main objective of this study was to develop and test the impact of a cassava chipping machine with a variable clearance and varying cutting speed on chip geometry. Drum operation speeds of 460 rpm, 730 rpm, and 800 rpm, and chipping clearances of 6 mm, 18 mm, and 28 mm were considered in this study. The study considered two twelve-month maturing varieties of cassava. These varieties were the Ampong (an improved variety) and Ankrah (a local variety). Processing time was varied between freshly harvested (FH) and 48 h after harvest (48AH). The initial moisture contents of the Ampong variety were 68.1% and 65.4% wet basis for the FH and 48AH samples, respectively. The Ankrah variety recorded 66.0% and 61.0% wet basis for FH and 48AH samples, respectively. Results from the performance evaluation test indicated that operational speed and chipping clearance had a significant effect (P<0.05) on the chips’ length, width, and thickness. Ankrah variety recorded the shortest mean chip length at 6 mm clearance and 730 rpm for the FH samples. On the other hand, Ampong samples at 730 rpm and 18 mm machine clearance recorded the shortest mean chip length for the 48AH samples.