On low-input smallholder farms of Kenyan upland landscapes, erosion of nutrient-rich topsoil strongly affects crop yields. Where maize (Zea mays) is intercropped on erosion-prone slopes, intercropping can potentially reduce soil erosion. The objective of this research was to quantify the contribution of crops and crop mixtures of different growth habits to erosion control and their influence on above-ground biomass and earthworm abundance as indicators of soil function in smallholder farming systems under a bimodal rainfall pattern in Western Kenya. The experiment involved five treatments, namely maize (Z. mays)/common bean (Phaseolus vulgaris) intercrop (maize intercrop), maize/common bean intercrop plus Calliandra (Calliandra calothyrsus) hedgerows and Calliandra mulch (Calliandra), sole Lablab (Lablab purpureus), sole Mucuna (Mucuna pruriens) and groundnut (Arachis hypogaea) intercropped with maize (during the short rains). The experiment was conducted over three consecutive cropping seasons and the cropping system had significant effects on soil loss, runoff, water infiltration, earthworm abundance and above-ground biomass and crop grain yield. The Calliandra treatment had the lowest runoff (11.6-17.2 mm ha −1 ) and soil erosion (31-446 kg ha −1 per season) in all the seasons, followed by the Mucuna treatment. Lablab was affected by disease and showed the highest soil erosion in the last two seasons. Infiltration was highest in Calliandra treatment, and earthworm abundance was higher under Mucuna and Calliandra treatments (229 and 165 earthworms per square metre, respectively) than under other crops. Our results suggest that including sole crops of herbaceous species such as Mucuna, or tree hedgerows with mixtures of maize and grain legumes has the potential to reduce runoff and soil erosion in smallholder farming. Additionally, these species provide a suitable habitat for earthworms which stabilise soil structure and macropores and thus potentially increase infiltration, further reducing soil erosion.

The emission of greenhouse gases (GHGs) results in global warming and climate change. The extent to which developing countries contribute to GHG emissions is not well known. This study reports findings on the effects of different land-use systems on GHG emissions (CO2 in this case) from two locations in the southern zone of Ghana, West Africa. Site one (located at Kpong) contained a heavy clay soil while site two (located at Legon) contained a light-textured sandy soil. Land-use systems include cattle kraals, natural forests, cultivated maize fields, and rice paddy fields at site one, and natural forest, woodlots, and cultivated soya bean fields at site two. CO2 emissions were measured using the gas entrapment method (PVC chambers). Trapping solutions were changed every 12–48 h and measurement lasted 9 to 15 days depending on the site. We found that, for the same land-use, CO2 emissions were higher on the clay soil (Kpong) than the sandy soil (Legon). In the clay soil environment, the highest average CO2 emission was observed from the cattle kraal (256.7 mg·m−2·h−1), followed by the forest (146.0 mg·m−2·h−1) and rice paddy (140.6 mg·m−2·h−1) field. The lowest average emission was observed for maize cropped land (112.0 mg·m−2·h−1). In the sandy soil environment, the highest average CO2 emission was observed from soya cropped land (52.5 mg·m−2·h−1), followed by the forest (47.4 mg·m−2·h−1) and woodlot (33.7 mg·m−2·h−1). Several factors influenced CO2 emissions from the different land-use systems. These include the inherent properties of the soils such as texture, temperature, and moisture content, which influenced CO2 production through their effect on soil microbial activity and root respiration. Practices that reduce CO2 emissions are likely to promote carbon sequestration, which will consequently maintain or increase crop productivity and thereby improve global or regional food security.

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Students’ level of academic engagement and achievement at any level of education is partly knit to the kind of relationships that exist between them and their teachers. The study examined the impact of teacher-student relationship on academic achievement of students in Senior High Schools in Winneba, Ghana. Eighty students were conveniently sampled from two strata whiles data was qualitatively collected using semi-structured interview guide and analyzed thematically. The study uses the four clusters of teacher-student relationship as a framework to discuss the types of relationships that exist in Ghanaian Senior High Schools. The study revealed that connectedness, dependent, peaceful and conflicting teacher-student relationships prevail in Senior High Schools. However, administrative restrictions, and certain attitudes of teachers and students impede the development of effective teacher-student relationship. Whereas positive relationships create environments that augment academic achievement, threatening relationships stifle academic achievement. Teachers should deliberately express concerns both about students’ academic and non-academic life, as this makes the latter feel accepted and motivated to improve academic work.

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