Abstract: The adequate supply of the ever-increasing demand of fresh water continues to be a global challenge due to increase in population. The anticipation for better lifestyles and improved water supply has resulted in an increase in migration from rural settlements leading to an increase in the populations of many cities globally. This study therefore investigates the variability and trends in the surface water demand and supply of the city of Gaborone and surrounding areas in respon...
Abstract: In the present study, an assessment on corrosion resistance of aluminium alloys type AA2036 and AA7075-T651 in varying solution consisting of acidic, saline and in contaminated acid-chloride environments was investigated using weight loss and electrochemical techniques. The as-received samples were sectioned into corrosion coupons polished, degreased and weight taken. Solutions containing 3.5 % NaCl, 0.5 M HCl, 0.5 M H2SO4 were prepared as corrosion media and combination of these s...
Abstract: Neoarchean granitoids are commonly exposed along Archean high-grade metamorphic terranes, where they occur as granitoid gneisses. A number of issues, including the effect of overprint event(s), can complicate the characterization of these granitoids in Archean terranes. A case study is presented here highlighting the complexity of characterizing Neoarchean granitoid magmatism from the Limpopo Complex high-grade terrane in southern Africa. Neoarchean granitoids occurring within the ...
Abstract: This paper introduces the various upstream land use activities that are major contributors of downstream water pollution. The proposed measures to reduce the pollution of downstream water bodies such as sustainable agricultural activities, systematic land allocation and management are discussed in the paper. It presents the analysis of upstream land use against the water quality parameters measured at different water management facilities to identify the most significant land use f...
Abstract: In this study, activated biochar from municipal sewage sludge was used for the treatment of sewage water. The sewage physicochemical parameters were measured before and after bio filtration with biochar applying the principle of adsorption using the standard methods. Biochar with 500 m2/g surface area at a loading of 2.5 g/L was employed. A reduction of more than 75% was observed for the total nitrogen, biological oxygen demand, chemical oxygen demand, total solids, electrical cond...
Abstract: This paper is a case study review of the timber waste problem and solutions that have been proffered in the Manicaland region of Zimbabwe. The study was conducted through primary data collected during site visits and a review of literature reports on the area. It revealed the absence of up to date quantitative and spatial data on timber waste, with literature reporting at least 70,000 tonnes per annum of sawmill waste. Most of the offcuts and chips are utilized at commercial sawmil...
Abstract: The recovery of precious metals like gold is increasing each day due to its high market prices along with diverse applications. Bio-sorption represents a biotechnological innovation as well as a cost effective and excellent tool for recovery of precious metals from aqueous solutions. This study offers an overview of a recent scenario of bio-sorption studies carried out on the use of some promising bio-sorbents which could serve as an economical means for recovering gold for small s...
Abstract: Plastics have remained the material of choice, and after serving their intended purpose, a large proportion ends up in the environment where they persist for centuries. The packaging industry is the largest and growing consumer of synthetic plastics derived from fossil fuels. Food packaging plastics account for the bulk of plastic waste that are polluting the environment. Additionally, given the fact that petroleum reserves are finite and facing depletion, there is a need for the d...
Abstract: Ammunition used for military training and exercises has been found to contain high content of lead (Pb). The Pb present in the ammunition projectiles undergoes an array of transformation and weathering reactions when it reaches the shooting range soils. Seven military shooting ranges in the eastern and northern Botswana were used for this study. Soil samples were collected at each of the seven shooting ranges at the berm (stop butt), target line, 50 and 100 m from the berm. Pb conc...
Abstract: Issues on environmental soil quality continue to attract much global attention. Domestic wastewater is a potential source of contaminants capable of degrading the soil environment. This study reports the accumulative effects of 21 years (1995 – 2016) of treated wastewater discharge on heavy metal concentration levels in the proximal environment of Palapye wastewater treatment Plant (PWTP), Central Botswana. Soil samples were collected from eight geo-referenced pedons: four situat...
Abstract: Vegetation plays a vital and important role in regulating climate, water balance and energy. This research examines vegetation variability and degradation in semi-arid Palapye, eastern Botswana. These were assessed over an 18 year period (1998 to 2016) using Remote Sensing based Normalized Difference Vegetation Index (NDVI) time series data. NDVI has been widely used as an indicator of vegetation growth because it measures the amount of plant greenness from the spectral responses m...
Abstract: In Botswana crop production has been the most vulnerable component of the agricultural sector due to its heavy reliance on rainfed agriculture. At the same time, the availability of rainfall is uncertain due to natural climatic variability which is worsened by climate change. Already the local farmers have knowledge of the climatic conditions around them, and from time to time, they have been adjusting their farming practices in line with the prevailing climatic conditions. Climate...
Abstract: Delonix regia, an ornamental tree that can tolerate an elevated level of heavy metals, was evaluated for phytoremediation potential in mine tailings with fly ash, compost, and mycorrhiza. A two-factorial experiment was conducted under screen house conditions using mine tailings from Bamangwato Concessions Limited (BCL) Cu-Ni mine. The treatments are mine tailing (MT) without mycorrhiza (MT – AM), MT with mycorrhiza (MT + AM), MT with 10% fly ash (FA) without mycorrhiza (MT + FA �...
Abstract: Droughts pose a significant challenge to water resources, causing several socio-economic consequences. The growing economy requires improved assessments of drought-related impacts in the water sector, particularly under semi-arid environments where its climate is getting drier and warmer. This study proposes a probabilistic model (copula approach) that is intended to contribute to the drought risk assessment by providing an essential information in drought prediction, decision...
Abstract: Citizens owned fuel transport companies in Botswana are startups and are operating at a small to medium scale. Being startups or Small and Medium Enterprises (SMEs), they are faced with similar challenges that confront most new small businesses. The aim of this study was to assess the challenges faced by citizen-owned fuel transport companies in Botswana and their influence on enterprise growth. The role of finance, human resources, industry experience, and government support was e...