Effects of Agroforestry Practices on Soil Properties in the Drylands of Eastern Kenya

Drylands, which are home to about 2 billion people face a myriad of problems among them low land productivity. Agroforestry is one of the land use practices that is perceived to be sustainable with beneficial effects on soil properties. However, the effects of agroforestry practices on soils especially in the drylands have rarely been quantified and studied in details. The study determined the effects of selected agroforestry practices on soil properties in Makueni County of Kenya where agroforestry has been promoted by various organizations. Four soil samples were collected at 0-15cm, 15-30cm, 30-45cm and 45-60cm depths in a zigzag pattern at each 10 x 10m plots established along line transects laid in woodlots established in 2007, 2010 and 2013 and their adjacent parkland and grazing land. Seven randomly selected farms were sampled. The samples were analyzed using laboratory methods for soil nutrients and physical properties. Density of tree species in these established plots were also determined using quadrat technique. Tree density was higher in woodlots followed by grazing area and parkland .Soil samples showed that Soil Organic Carbon and Total Nitrogen were significantly higher in the woodlots than in the parkland and grazing lands ((p≤0.05). Soil Organic Carbon was significantly higher in woodlots established in 2007 than those established in 2013. Phosphorus was significantly higher in cropland compared to woodlots and grazing land. Phosphorus and Potassium were significantly higher at 0-15 cm depth compared to other soil depths. Bulky density was significantly higher with a corresponding lower total porosity in grazing lands than in the woodlots and parklands. The results suggest that different agroforestry practices contribute differently to soil properties. Mixed tree woodlots contributed significantly to improving soil properties and could be considered as a strategy to sustainably restore degraded and infertile soils in the drylands

Self-Help Food and Fuel Supplements for Impoverished Communities in Kenya

Infection by the Human Immunodeficiency Virus causing Acquired Immune Deficiency Syndrome (HIV/AIDS) is a devastating pandemic worldwide. Globally an estimated 40 million people are currently infected with the virus and about 20 million people have died. Within Kenya’s population of 35 million at least two million people are living with HIV/AIDS disease while 1.5 million have perished from the scourge. Research suggests that malnutrition leads to immune system impairment, exacerbates the effects of HIV/AIDS, and contributes to a more rapid progression of the disease. Medication for HIV patients helps little in the absence of adequate nutrition. The lifesaving benefits of antiretroviral (ARV) treatment have been established in Kenya, but due to poverty and food insecurity leading to poor nutrition among HIV patients, the full benefits of ARV treatment are often nullified. Nutrition intervention to date is lagging, with current international humanitarian practices and research tending to focus on food aid supplements with little support for local production of a balanced, fresh and nutritional diet for people affected by HIV/AIDS. Urgent self-help food security is needed locally. A sustainable approach is to combine antiretroviral drugs with adequate nutrition from food grown locally by patients and their families themselves. To sterilize water by boiling and to cook food, these same HIV-affected persons need a sustainable, convenient and affordable source of domestic fuelwood, too. In Kenya, over 75% of the people use fuelwood as either firewood or charcoal as the most accessible source of energy. However, this practice has led to massive depletion of woody vegetation and fuelwood shortages spurring demand and skyrocketing prices of charcoal and/or firewood. Therefore, an environmentally and economically sound method of sustainable fuelwood production for domestic use in Kenya is an urgent need. Utilizing dryland indigenous trees and shrubs in polyculture agroforestry systems for sustained yield harvesting is an attractive alternative to the current unsustainable, illegal taking of wood from forest reserves. Small-plot agroforestry with native dryland woody species adapted to local conditions holds great promise for self-help fuel production. As part of GEM projects addressing HIV/AIDS and sustainable agriculture and forestry, this thesis addresses both critical needs of self-help food and fuel security for impoverished communities in Kenya. For self-help food production training, different organic gardening techniques such as compost-making, organic polyculture, square-meter garden and sack garden establishment, plant pest and disease management, and maintenance were deployed with over 1,200 persons trained and over 700 gardens installed within a one-year period. For self-help fuelwood production, a seedling nursery experiment was designed to test early growth responses of promising dryland woody species and provenances for sustainable fuelwood and charcoal production. Both kitchen garden and backyard domestic fuelwood systems can be implemented through a simple integrated, sustainable agroforestry design for family households in Kenya and elsewhere worldwide. This self-help food and self-help fuel project contributed significantly to GEM’s grassroots progress towards achieving six Millennium Development Goals: [MDG 1] eradicate extreme poverty and hunger; [MDG 3] promote gender equality and empower women; [MDG 4] reduce child mortality; [MDG 5] improve maternal health; [MDG 6] combat HIV/AIDS, malaria and other diseases; and [MDG 7] insure environmental sustainability

Car Antifreeze and Coolant: Comparing Water and Ethylene Glycol as Nano Fluid Base Fluid

Most internal combustion engines are fluid cooled using liquid coolants mostly water and ethylene glycol, whose heat transfer capabilities are limited. An alternative for improving their thermophysical properties is the addition of metal oxides so as to make Nanofluids. This study investigates car antifreeze and coolants by comparing water-based and ethylene glycol based Nanofluids to determine the Nanofluid which provides optimum cooling. The governing equations are non–dimensionalised using similarity transformation and the resulting equations solved numerically using the Runge–Kutta fourth order scheme. Graphical results of pertinent parameters on fluid velocity, temperature, skin friction and rate of heat transfer are presented and discussed in depth putting into consideration the industrial application. It was observed that the magnetic field slows the fluid flow while increasing the fluid temperature. Also ethylene glycol Nanofluid offers better cooling capabilities

Attitudes towards vaccines and intention to vaccinate against COVID-19: a cross-sectional analysis - implications for public health communications in Australia

Objective To examine SARS-CoV-2 vaccine confidence, attitudes and intentions in Australian adults as part of the iCARE Study. Design and setting Cross-sectional online survey conducted when free COVID-19 vaccinations first became available in Australia in February 2021. Participants Total of 1166 Australians from general population aged 18-90 years (mean 52, SD of 19). Main outcome measures Primary outcome: responses to question € If a vaccine for COVID-19 were available today, what is the likelihood that you would get vaccinated?'. Secondary outcome: analyses of putative drivers of uptake, including vaccine confidence, socioeconomic status and sources of trust, derived from multiple survey questions. Results Seventy-eight per cent reported being likely to receive a SARS-CoV-2 vaccine. Higher SARS-CoV-2 vaccine intentions were associated with: increasing age (OR: 2.01 (95% CI 1.77 to 2.77)), being male (1.37 (95% CI 1.08 to 1.72)), residing in least disadvantaged area quintile (2.27 (95% CI 1.53 to 3.37)) and a self-perceived high risk of getting COVID-19 (1.52 (95% CI 1.08 to 2.14)). However, 72% did not believe they were at a high risk of getting COVID-19. Findings regarding vaccines in general were similar except there were no sex differences. For both the SARS-CoV-2 vaccine and vaccines in general, there were no differences in intentions to vaccinate as a function of education level, perceived income level and rurality. Knowing that the vaccine is safe and effective and that getting vaccinated will protect others, trusting the company that made it and vaccination recommended by a doctor were reported to influence a large proportion of the study cohort to uptake the SARS-CoV-2 vaccine. Seventy-eight per cent reported the intent to continue engaging in virus-protecting behaviours (mask wearing, social distancing, etc) postvaccine. Conclusions Most Australians are likely to receive a SARS-CoV-2 vaccine. Key influencing factors identified (eg, knowing vaccine is safe and effective, and doctor's recommendation to get vaccinated) can inform public health messaging to enhance vaccination rates