Large-scale coal mining is being carried out in Tete province, Mozambique. This area is also being planned to become a large coal fired power production hub serving electricity to neighboring ...countries in southern Africa. Thus, huge amounts of coal will be burned, resulting in the generation of a large quantity of coal ash. High concentrations of hazardous elements are often released from coal and coal ash causing negative impacts to human health and the environment. Therefore, it is important to understand the possibility of hazardous elements leaching. Aqueous batch leaching experiments under ambient conditions were conducted using six coal samples and their ash. Most of the coal leached very low concentrations of hazardous elements. However, an absence of carbonate minerals gave rise to higher acidity levels. This resulted in elevated leaching concentrations of manganese and iron, regardless of their contents. Burning coal resulted in higher contents of hazardous elements in the ash. However, leaching concentrations of most of the elements from the ash samples were still lower than the environmental standards. Chromium and manganese were enriched in slightly acidic leachates regardless of their contents while higher arsenic than the permitted level was leached from the ash containing the highest arsenic content that generated neutral pH leachate. These findings highlight a possibility of hazardous elements contamination from Mozambican coal and coal ash. Therefore, the storage of coal and disposal of coal wastes and ash in Tete Province should be done carefully and monitored to avoid the contamination in the region.
•Leaching properties of hazardous elements from coal and coal ash are different.•Coal ash has higher leachability than its parent coal.•Leachate with lower pH promotes the mobility of some hazardous elements.•There is a possibility of hazardous element contamination from coal and coal ash.
The now classic "Pocket Pasha"--Otolaryngology-Head and Neck Surgery: Clinical Reference Guide--returns for its sixth edition. This universally standard guidebook concisely reviews all aspects of ...otolaryngology including rhinology, laryngology, otology, plastic surgery, sleep medicine, and more. All chapters focus on the key basic science and clinical information to quickly digest the essentials. This "high-yield" book retains a "by residents, for residents" feel while also including expert content useful not only for students and residents but also allied health professionals, primary care providers, and other health providers. The concise, outline format is useful for rapid reading during urgent clinical situations as well as a last-minute refresher before rounds. The guide has proven essential for board review and maintenance of certification exams.
•Potential glacier bed overdeepenings (GBOs) in the Mont Blanc massif are studied.•Predicted locations and morphologies of GBOs are compared to field observations.•Levels of confidence are determined ...and ranked for each predicted GBO.•The timing of potential future lake (PFL) formation in GBOs is roughly estimated.•A baseline for an integrative risk assessment associated to PFL is given.
De-glaciating high mountain areas result in new landscapes of bedrock and debris where permafrost can degrade, persist or even newly form in cases, and of new lakes in glacier bed overdeepenings (GBOs) becoming ice-free. These landscapes with new lakes in close neighborhood to over-steepened and perennially frozen slopes are prone to chain reaction processes (e.g. rock-ice avalanches into lakes triggering impact waves, dam breach or overtopping, and debris flows) with potentially far-reaching run-out distances causing valley floors devastation. The frequency, magnitude and zonation of hazards are shifting, requiring integrative approaches combining comprehensive information about landscape evolution and related processes to support stakeholders in their adaptation strategies. In this study, we intend to setup an essential baseline for such an integrative approach in the Mont Blanc massif (MBM), which is a typical high-mountain range affected by de-glaciation processes. We first (i) predict and (ii) detect potential GBOs by combining the GlabTop model with a visual analysis based on morphological indications of glacier flow through over-deepened bed parts. We then (iii) determine the level of confidence concerning the resulting information, and (iv) estimate the approximate time range under which potential lakes could form. The location of the predicted GBOs and the shape of glacier beds are evaluated against currently forming water bodies at retreating glacier snouts, and seismic and ice penetrating radar measurements on the Argentière glacier. This comparison shows that the location of predicted GBOs is quite robust whereas their morphometric characteristics (depth, volume) are highly uncertain and tend to be underestimated. In total, 48/80 of the predicted or detected GBOs have a high level of confidence. In addition to five recently formed water bodies at glacier snouts, one of the high confidence GBOs (Talèfre glacier) which is also the most voluminous one could form imminently (during coming years), if not partially or totally drained through deeply incised gorges at the rock threshold. Twelve other lakes could form within the first half of the century under a constant or accelerated scenario of continued glacier retreat. Some of them are located below high and permanently frozen rock walls prone to destabilization and high-energy mass movements, hinting at possible hot spots in terms of hazards in the coming decades, where more detailed analysis would be required.
In Tete Loeper's novel Barefoot in Germany (2020), Black first-person narrator Mutoni from Rwanda recounts her experiences as a marriage migrant, sex worker, maid, and caregiver in Germany, a ...supposed "Happyland" where racism is considered the offense of "others": bad individuals and Nazis. However, Loeper's white savior characters are both nice people and (unwitting) racists, while some of Mutoni's Black sisters behave in discriminatory ways as well. Drawing on critical race theory and imagology, this article shows how the novel deconstructs and appropriates stereotypical images from "'colorblind' Europe" on both a thematic and formal-aesthetic level. By engaging with a comparative and transnational frame of reference that goes beyond a monolingual white canon of theory and literature, the article reveals the novel's connections to other Black texts and genres, as well as its literary strategies in dealing with identity (politics).
The Permian–Triassic transition has been identified for the first time in the Karoo Supergroup of the Moatize–Minjova Basin in Mozambique. This transition was identified in the subsurface in deep ...(ca. 500m) coal exploration boreholes that penetrated the Matinde Formation. Two palynomorph assemblages (assemblage 1 and assemblage 2) assigned to the latest Permian were defined for the Matinde Formation. These assemblages are both dominated by taeniate pollen, cavate trilete spores of Kraeuselisporites spp., associated with conifer (Lueckisporites virkkiae) and pteridosperm pollen (Guttulapollenites hannonicus and Weylandites lucifer). Assemblage 3 represents a microfloral turnover. For the first time specimens of Lunatisporites pellucidus appear in an assemblage dominated by lycopod spore taxa such as Lundbladisporites spp. This assemblage was assigned to the Early Triassic and occurs at the top of borehole DW 132 within the Matinde Formation. The palynostratigraphic signature obtained for the Permian–Triassic transition puts the Moatize–Minjova Basin in the central Gondwana palaeobiogeographic province with strong affinities with the Karoo basins of Madagascar and the Salt Range Basin in Pakistan. These new data indicate that coal deposits accumulated in the Moatize–Minjova Basin until the latest Permian and that these are possibly more extensive temporally than previously described, opening new perspectives for coal and unconventional hydrocarbon exploration in this basin.
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•Permian–Triassic transition was identified in Karoo succession in Mozambique.•Mozambique was part of the central Gondwana palaeobiogeographic province.•Data opens new perspectives for coal and unconventional hydrocarbons exploration.
•Coal mining activities are being carried out in Moatize district, Tete province, Mozambique.•The impact of coal mining on the surrounding environment were evaluated.•Surface water and groundwater ...were contaminated with As, Cr, Cu, Ni, Mn and Pb.•As, Cd, Cr, Mn and Pb release from the surrounding surface soils and river sediments exceeded environmental standards.
Water, soils, and sediments contaminated with hazardous elements are of increasing concern because they greatly affect human health and ecological systems. In Mozambique, coal mining and processing operations are important industries; however, they could potentially contaminate the surrounding environment. This study investigates contamination of surface soils, river sediments, river water and groundwater around coal mines in Moatize district, Tete province, Mozambique. Three water pollution indices, water quality index (WQI), heavy metal evaluation index (HEI) and heavy metal pollution index (HPI) and five soil/sediment pollution indices, enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF), contamination degree (CD) and pollution load index (PLI) were used to assess the levels of contamination in the area. All water samples were found to be “uncontaminated” to “moderately contaminated” with hazardous metals. The heavy metal concentrations found in waters varied from: As (0.3–10.9 µg/L), Ba (9.8–69.6 µg/L), Cr (2.1–60.2 µg/L), Cu (1.7–62.3 μg /L), Ni (1.2–71.9 μg /L), Mn (5.9–58.1 µg/L), Pb (1.3–10.8 μg /L) and Zn (2.1–40.2 µg/L). Most of these values exceeded the drinking water standards set by WHO. Meanwhile, surface soils and sediments from Moatize and Murrongoze Rivers were “highly polluted” (PLI = 1.11–1.85). Leaching experiments of soil and sediments suggest that hazardous elements from soils and sediments were strongly affected by the type of leaching solution (deionized 18 MΩ cm water and 1M HCl) and several of them were highly bio-accessible that could pose serious ecological and health risks in the area.
•Maximum depositional age of the arc-related Chidzolomondo Complex at 1120 Ma.•Syn-orogenic charnockite and gabbro dated at 1097 Ma and 1061 Ma, respectively.•HT-LP syn-orogenic metamorphism between ...1092 and 1060 Ma.•Thermal metamorphism due to the late-orogenic charnockite intrusion at 1026 Ma.
In the Mesoproterozoic Southern Irumide Belt, Tete Province, NW Mozambique, granulite-facies metavolcaniclastic rocks and orthogneisses from the Chidzolomondo Complex provide new constraints on the subduction and accretionary phases of the belt evolution. The complex comprises a metavolcano-sedimentary succession intruded by syn- to post-orogenic granitoids, charnockites and gabbros. The paragneisses exhibit a calc-alkaline chemical composition akin to intermediate magmatic rocks found in volcanic arcs. They are interpreted as products of a three-component mixture, consisting of pelite-aluminous, quartz, and reworked mafic volcanic rocks. A paragneiss sample contains detrital zircon with ages mainly between 1344 and 1098 Ma and εHf(t) values between −10 to +7, defining a maximum depositional age of 1121 ± 2 Ma. A charnockitic gneiss, dated at 1097 ± 3 Ma, and a metagabbro, dated at 1061 ± 3 Ma, respectively, represent the syn- and late-orogenic magmatic events. Both rocks exhibit juvenile εHf(t) signatures ranging from +1.5 to +4.5. The mineral assemblage of cordierite + garnet + orthopyroxene in metavolcaniclastic rocks, and plagioclase + hypersthene + diopside in the metagabbro, provide evidence of the HT-LP metamorphic conditions. Phase equilibria modeling of a paragneiss indicates that the peak metamorphic conditions reached approximately 785–795 °C and 3.7–4.2 kbar. By dating of zircon overgrowths in granulite-facies gneisses, we characterized the orogenic (M1) and thermal (M2) metamorphisms that affected the complex. The M1 event records the subduction-type and accretion metamorphism dated between 1092 and 1060 Ma. The M2 event, identified in the metagabbro sample close to the contact with a charnockite intrusion, yielded an age of 1023 ± 12 Ma for the thermal metamorphism. Intrusive charnockite and a gabbro record the post-orogenic magmatism with ages of 1026 ± 4 Ma and 1026 ± 12 Ma, respectively. The results provide a timeline for the last orogenic events of the Southern Irumide Belt, including the maximum depositional age of the Chidzolomondo Complex at ca. 1120 Ma, syn-orogenic magmatism and metamorphism until ca. 1060 Ma, and late- to post-orogenic magmatism and metamorphism between 1050 and 1020 Ma.
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