Vesicular arbuscular mycorrhizal fungi prevalence and diversity in Zimbabwean soils

A JASSA article on the prevalence and population levels of VAM fungi in a range of field soil environments in Zimbabwe.The prevalence and population levels of VAM fungi in a range of field soil environments in Zimbabwe were determined. The main VAM genera Acaulospora, Scutellospora, Gigaspora, Glomus, Sclerocystls and Entrophospora were represented in the study sites. The relative abundance was Glomus > Acaulospora > Scutellospora > Sclerocystis > Gigaspora > Entrophospora at all sites except at Chabwino (fallow soil) and Thorn Park (sorghum) where Acaulospora Scutellospora = Acaulospora. Relative proportions of the different VAM genera were similar across soils but population sizes varied with soil management. There was no clear relationship between VAM spore numbers and cropping history although among the cultivated plots, soils that had legumes as the previous or current crop generally had higher VAM populations than under sorghum. Of the soil parameters measured, only percent organic carbon was significantly correlated with VAM numbers and infective propagules

Household cooking fuel use patterns and determinants across Southern Africa : evidence from the demographic and health survey data

Abstract: Improving access to modern energy sources is critical to enhancing the quality of life of many people in developing countries. In southern Africa, the majority of rural and poor urban households are dependent on solid fuels to meet their cooking needs. This has adverse effects on health, productivity, and environmental sustainability. To date, there is scarce information in the literature on household cooking fuel patterns and choice determinants across the southern African region. Using household fuel data from the Demographic and Health Survey (DHS), this study investigated cooking fuel types and the determinants of their choice by households in selected countries in sub-Saharan Africa. The data on household cooking energy were subjected to descriptive and inferential statistics. Results show that 25% of sampled households in all seven countries have access to electricity, while 66% rely on biomass for cooking. Chi-Square analyses revealed a statistically significant relationship between place of residence and type of cooking fuel, and between access to electricity and type of cooking fuel. Results from multiple regression analysis showed that socio-demographic factors such as access to electricity, household size, level of education, and wealth index have a positive influence on the type of cooking fuel used in this region. However, access to electricity does not imply that households will negate the use of traditional fuels. These results have implications for household air pollution, health, policy and environmental sustainability. It is recommended that energy interventions in this region need to consider demand factors and have to be less supply driven, advocating for continued use of multiple fuels from a suite of options

Influence of coal-particle size on emissions using the top-lit updraft ignition method

Despite the Government’s intervention of an intensive electrification program in South Africa, which has resulted in more than 87% of households being connected to the grid, a majority of low-income households still depend on solid fuel (coal and wood) as a primary source of energy, especially on the central Highveld. In informal settlements, combustion of coal is done in inefficient self-fabricated braziers, colloquially known as imbaulas. Emissions from domestic coal combustion result in elevated household and ambient air pollution levels that often exceed national air quality limits. Continued dependence on coal combustion exposes households to copious amounts of health-damaging pollutants. Despite the health significance of coal-burning emissions from informal braziers, there is still a dearth of emissions data from these devices. Consequently, evaluating the emission characteristics of these devices and to determine the resultant emission factors is needed. The effects of ignition methods and ventilation rates on particulate and gaseous emission from coal-burning braziers are reported in literature. However, to date there are no studies carried out to investigate the influence of the size of coal pieces on brazier emission performance. In this paper, we report on controlled combustion experiments carried out to investigate systematically, influences of coal particle size on gaseous and condensed matter (smoke) emissions from informal residential coal combustion braziers. Results presented are averages of three identical burn-cycles of duration three hours or fuel burn-out, whichever was the soonest

Cooking sequences : the realistic utilization of fuel/stove combinations in standardised experiments

Abstract: The development of stove performance evaluation standards and protocols has received significant attention in the past decade. This was given the impetus by the advent of the Global Alliance for Clean Cookstove (GACC). Currently, there is a huge drive to developing an international stove-testing standard that addresses real-world uses of fuel/stove combinations. The study was conducted to evaluate the performance of a biomass pellet cookstove using uncontrolled cooking test (UCT) with cooking sequences derived from food dishes prepared in the lowincome stratum of Johannesburg. Results show that cooking sequences, when incorporated in standardised stove testing protocols, offer the potential to correlate better the laboratory and field performances of fuel/stove combinations. This is because cookstoves are operated, during technical test experiments, the way they would in real world-uses by mimicking the preparation of specific food dishes. Results from this study have implications for the development of future stove testing protocols

Household energisation in rural South Africa : a systems approach towards energy access

Abstract: In South Africa, household electrification has improved significantly since the dawn of independence, with the current national electrification rate at 87%. However, poor households in rural communities, informal urban settlements and low-income urban Townships still rely heavily on traditional fuels to meet their basic energy needs. The majority of these households are energy poor, as they tend to expend a higher proportion (> 10%) of their disposable income on energy services. The continued use of traditional fuels is associated with health challenges including asphyxiation, upper and lower respiratory complications, and mortality. Notwithstanding the benefits of household electrification in rural areas, there is a great need to consider other cheaper alternative energy sources, as the cost of electricity tends to limit its use. Household “energisation” instead of “electrification” has the potential to provide households with access to clean renewable energy sources at minimal cost. Effective household energisation employs a systems approach towards a more comprehensive energy access strategy of meeting households’ energy needs using a suite of locally available renewable energy carriers. Energy options available for rural communities are assessed using a ‘systems thinking’ approach

Biological Nitrogen Fixation: Sustaining African Agriculture into the Twenty-First Century?

A conference paper on sustaining African agriculture in the twenty-first century.The main objective of the African Association for Biological Nitrogen Fixation (AABNF) is to promote research, training and the use of biological nitrogen fixation systems to increase food production, reduce the need for purchased nitrogen fertiliser inputs, alleviate malnutrition and improve the environment in Africa. This objective contributes to the conservation and sustainable use of natural resources, and the sharing of benefits arising out of the utilisation of the results of relevant research, all key considerations in national development strategies, plans and programmes, as stipulated in Agenda 21 and in a number of Conventions in particular the Convention on Biological Diversity. The research carried out by scientists working on BNF in Africa has confirmed in controlled environments and in both experimental and farmers’ fields, the potential of biological nitrogen fixing systems to contribute to sustainable agriculture. In particular, the potential benefits to the well-being of the populations living in rural areas are significant

Vesicular arbuscular mycorrhizal fungi prevalence and diversity in Zimbabwean soils

The prevalence and population levels of VAM fungi in a range of field soil environments in Zimbabwe were determined. The main VAM genera Acaulospora, Scutellospora, Gigaspora, Glomus, Sclerocystis and Entrophospora were represented in the study sites. The relative abundance was Glomus>Scutellospora>Sclerocytis>Gigaspora>Entrophospora at all sites except at Chabwino (fallow soil) and Thorn Park (sorghum) where Acaulospora>Scutellospora and Sclerocytis>Scutellospora = Acaulospora. Relative proportions of different VAM genera were similar across soils but population sizes varied with soil management. There was no clear relationship between VAM spore numbers and cropping history although among the cultivated plots, soils that had legumes as the previous or current crop generally had higher VAM populations than under sorghum. Of the soil parameters measured, only percent organic carbon was significantly correlated with VAM numbers and infective propagules. Journal of Applied Science in Southern Africa Vol.5, No.1 pp. 35-4

Perception of the use of pre-paid electricity meters in Chidzidzi, Mutoko, Zimbabwe

Abstract: Since the era of the economic adjustment program, the Zimbabwe Electricity Supply Authority (ZESA) Holdings has been faced with an increasing problem of non-payment of electricity service charges, especially in the medium- to low-income households. In the early 2000s, the power utility company resorted to disconnections and the removal of post-paid electricity meters for non-paying households. Many customers accused ZESA Holdings of overcharging them on their monthly bills through the post-payment plan. As a way of recovering costs from non-paying households, ZESA Holdings resorted to the deployment of prepaid electricity meters, which automatically disconnect when households pre-coded electricity tokens are used up. The objective of this study is to understand consumers’ perception of the use of prepaid electricity meters versus the post-paid system, in Chidzidzi, Mutoko, Zimbabwe. Lessons learnt from this study are useful for informing policy in the country and other developing countries

A study on the prevalence of dog erythrocyte antigen 1.1 and detection of canine Babesia by polymerase chain reaction from apparently healthy dogs in a selected rural community in Zimbabwe

A study was carried out to determine the prevalence of blood group antigen dog erythrocyte antigen (DEA) 1.1 in mixed breed dogs in rural Chinamhora, Zimbabwe. DEA 1.1 is clinically the most important canine blood group as it is the most antigenic blood type; hence, DEA 1.1 antibodies are capable of causing acute haemolytic, potentially life-threatening transfusion reactions. In this study, blood samples were collected from 100 dogs in Chinamhora, and blood typing was carried out using standardised DEA 1.1 typing strips with monoclonal anti–DEA 1.1 antibodies (Alvedia® LAB DEA 1.1 test kits). Polymerase chain reaction for detecting Babesia spp. antigen was carried out on 58 of the samples. Of the 100 dogs, 78% were DEA 1.1 positive and 22% were DEA 1.1 negative. A significantly (p = 0.02) higher proportion of females (90.5%) were DEA 1.1 positive than males (69.0%). The probability of sensitisation of recipient dogs following first-time transfusion of untyped or unmatched blood was 17.2%, and an approximately 3% (2.95%) probability of an acute haemolytic reaction following a second incompatible transfusion was found. Babesia spp. antigen was found in 6.9% of the samples. No significant relationship (χ2 = 0.56, p = 0.45) was found between DEA 1.1 positivity and Babesia spp. antigen presence. Despite a low probability of haemolysis after a second incompatibility transfusion, the risk remains present and should not be ignored. Hence, where possible, blood typing for DEA 1.1 is recommended. A survey of DEA 3, 4, 5 and 7 in various breeds is also recommended