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: Human exposure to Naturally Occurring Radioactive Materials (NORMs) and toxic heavy metals has been a concern for the entire history of mankind since they are com monly found in the environment. Their increased levels are a result of anthropogenic activities such as mining. A-cap Resources Ltd, now A-cap Energy Ltd company dis covered that there were large uranium deposits in the underlying rocks of Serule. It was given licensing to start mining in 2016 with a lease of about 144 km...
Abstract: Shooting ranges continue to pose environmental and human health risk due to the accumulation of toxic Pb emanating from munitions. Remediation of Pb pollution at shooting ranges has been carried out through application of various techniques of which chemical stabilization is the most common. In some instances, field chemical stabilization has achieved Pb decontamination of the soils to concentrations below the maximum contaminant limits as set by the United States Environmental Pro...
Abstract: Bacterial diversity is known to be a driver of soil ecosystem services and it is influenced by the natural integrity of the environments. Samples from garden soil, saline soil and sludge-impacted soil were studied to evaluate the influence of soil properties on bacterial abundance and diversity for improved management. Soil samples were collected from 0 to 15 cm depth and analyzed for selected physico-chemical properties using routine labo- ratory procedures. 16S rRNA gene-based me...
Abstract: Commissioned and de-commissioned shooting ranges continue to pose an environmental and human health risk due to the accumulation of toxic Pb emanating from spent munitions. The phytotoxic effects of Pb accumulation in plants include inhibition of root growth and lowering of plant metabolism. The uptake of Pb by plants is directly affected by factors such as plant species and physicochemical properties of the soil. However, scientists and researchers have leveraged on the ability of...