Lack of long-term scientific land cover and erosional data impedes the development of sustainable land management plans to tackle land degradation and soil erosion problems in Tanzania. Using Landsat imagery, almost three decades of land cover change in the Lake Manyara catchment (1988-2016) was reconstructed. Data highlight that the major land cover types are highly dynamic and that there is a net conversion of natural or semi-natural land cover towards agricultural uses. Specifically, the biggest net declining cover types were found to be 'bushland', 'seasonal grassland' and 'permanent savanna', which have reduced by 8.7, 6.1 and 3.5% respectively. In this context an erosion risk model, based on the 'Revised Universal Soil Loss Equation', was applied to evaluate how changing land cover has affected risk of surface soil erosion by water. Model outputs indicate that a lot of land conversion has occurred in areas that are naturally vulnerable due to topography, soil type and rainfall patterns, seriously increasing the soil erosion risk. The resulting output maps can be particularly useful in pinpointing potential areas of increased erosion risk underpinning targeted investigation and management action to support soil conservation for improved food and water security.

Background : Ethiopia reported the first case of COVID-19 on March 13 th , 2020 with community transmission ensue by mid-May. National, population-based serosurvey against anti-SARS-CoV-2 IgG was conducted to measure the prevalence of prior COVID-19 infections and better approximate the burden across major towns in Ethiopia. Methods : We conducted a cross-sectional, population-based serosurvey from June 24 to July 8, 2020 in 14 major urban areas. Two-stage cluster sampling was used to randomly select enumeration areas and households. All persons aged ≥15 years were enrolled. Serum samples tested by Abbott™ ARCHITECT™ assay for SARS-CoV-2 IgG antibodies. National COVID-19 surveillance data on the median date of the serosurvey is analyzed for comparison. Findings : Adjusted seroprevalence was 3.5% (95% CI: 3.2%-3.8%) after controlling for age, sex and test kit performance. Males (3.7%) and females (3.3%) were nearly equally infected, while middle-aged adults 40-65 years had the highest (4.0%) prevalence. Gambella (7.5%), Dire Dawa (6.2%) and Jigjiga (6.1%) were most affected towns. About 6.7% and 8.0% of seropositives had symptoms and chronic underlying illness, respectively. Surveillance system had identified 4,416 RT-PCR confirmed cases in Addis Ababa. Interpretation : This serosurvey shows majority of urban Ethiopians remain uninfected with SARS-CoV-2. Most anti-SARS-CoV-2 IgG positive cases were asymptomatic with no underlying illness, keeping case detection to a minimum.

Hydrogeochemical investigations were carried out in Newcastle, in the KwaZulu-Natal province of South Africa to identify the major geochemical processes that control groundwater chemistry. 31 samples were collected and analysed for Magnesium (Mg2+), Calcium (Ca2+), Sodium (Na+), Potassium (K+), Chloride (Cl-), Sulfate (SO42-), Bicarbonate (HCO3-), Nitrate (NO3-), Fluoride (F-), pH, TDS and EC. Classical hydro-chemical methods; facies analysis and major ion analysis were used to further understand the composition controlling processes. It was inferred from the hydro-chemical facies, major ion scatter plots that the major process affecting the groundwater chemistry in the area is rock-water interaction. The ionic concentration is due to silicate weathering, carbonate weathering and ion exchange processes.

<p><strong>Background</strong></p> <p>During the recent worldwide lockdowns due to the COVID-19 pandemic, several institutions around the world, out of necessity replaced their customary field work with virtual field trips, using existing photographic materials gathered over many years conducting the same fieldtrip, causing the lecturers to conclude that this was a reasonable alternative as the marks scored were similar. </p> <p>Several years before the pandemic hit, UWC’s Applied Geology section had already embarked on the development of high-resolution virtual field tours (VFTs)to use as supplementary material in the provision of field education to our geology students, based on the geocognition concept.  This was done as rising costs and increasing health and safety rules effectively forced us to keep fieldwork for students to an absolute minimum, which is unacceptable in geology education. Additionally, in this manner, students could be exposed to classical geology sites from anywhere in the world without having to travel there, as an archive of prime teaching outcrops could be built like this.</p> <p><strong>Methodology</strong></p> <p>We created the Virtual Field Tours using High Resolution Photography and constructed the tours using Pano2VR enhanced with videos and drone images. In three different projects we tested for learning gain after exposure to our VFTs by using identical pre and post VFT questionnaires. Pandemic restrictions forced us to replace our first-year introductory field trips by VFTs.</p> <p><strong>Key Results</strong></p> <p>In a final assessment testing for understanding of geological principles based on their usage of these VFTs, the assessment results for first year students showed encouraging signs of learning gains. In the second project we exposed second year students, third year students and Honours students as well as graduate geologists to the basic principles of slope stability in engineering geology. In this case we presented a lecture, followed by a questionnaire on the concepts mentioned, followed by the VFT and again the same questionnaire where we demonstrated a distinct learning gain. Finally, we used a lecture on basic characteristics of sedimentary features in turbidite deposits, enhanced by a comprehensive VFT to prepare Honours level students for a weeklong field trip. Comparing their final report with the final report of the previous year’s group of students also demonstrated learning gain.</p> <p><strong>Conclusion</strong></p> <p>While we acknowledge that real-life field work can never be replaced, we have demonstrated that properly designed VFTs can be successfully used to enhance learning at real-life field work.</p>

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