Research Articles (LSD)

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Browsing Research Articles (LSD) by Author "Lewis, Earl W."

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    Monitoring groundwater quality in a Namibian rural settlement
    (2018) Lewis, Earl W.; Claasen, Tiffany
    Drinking water in rural areas is often contaminated due to poor sanitation practices, which cause problems such as diarrhea, polio and cholera. Rural water quality is a critical issue in Namibia because a great deal of the population lives in rural settlements. The aim of this study was to assess the levels of nitrate and some microbial parameters in borehole waters in 8 rural settlements in Hardap, Namibia. The tests were conducted in 2016 and the results compared to tests on the same boreholes in 2011. Parameters were determined using standard procedures. Water infrastructure and sanitation practices were also examined. Water parameters were compared to NamWater safe water drinking guidelines. The results revealed that sanitation practices need to be improved to avoid health risks. High levels of nitrate and coliform bacteria were identified as the most threatening contaminants that were determined.Water quality has deteriorated in these settlements since 2011, when only two of the boreholes yielded water unfit for drinking. In 2016 the number of unfit boreholes had increased to four. Systematic monitoring of groundwater quality, workshops on public health and sanitation practices, and improved sanitation facilities are recommended.
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    Using Benthic macro-invertebrates to assess ecological status of the Arbuga river in the, Sengiley Mountains, national park, Russia
    (2016) Lewis, Earl W.
    The objective of this study was to assess water quality of the Arbuga River in one of the National Parks in Russia, which is under severe stress from anthropogenic activities, using benthic macro-invertebrates as biological indicators. The study was carried out in 2012 and the findings were compared to an earlier study done in 2000. The indices used in the study to describe the invertebrate community species abundance were the Shannon-Weaver index and a density index (dominance). To assess the ecological status of the Arbuga River the Biotic Trent River Index was used. The results confirmed that the Arbuga River was in a moderately-polluted to critically polluted condition in some areas due to a range of anthropogenic impacts, at the time of the study. The health of the river had degraded from good to moderately-polluted since 2000 because of a range of anthropogenic factors.