Distribution Law of the Temperature Inversion Layer in a Deep Open-Pit Mine.
Ontology highlight
ABSTRACT:
SUBMITTER: Wang Y
PROVIDER: S-EPMC8015107 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Mine pit lakes ('pit lakes') are new aquatic ecosystems of the Anthropocene. Potentially hundreds of meters deep, these lakes are prominent in the landscape and in the public consciousness. However, the ecology of pit lakes is underrepresented in the literature. The broad goal of this research was to determine the environmental drivers of pelagic microbe assemblages in Australian coal pit lakes. The overall experimental design was four lakes sampled three times, top and bottom, in 2019. Instrument chains were installed in lakes and measurements of in situ water quality and water samples for metals, metalloids, nutrients and microbe assemblage were collected. Lakes were monomictic and the timing of mixing was influenced by high rainfall events. Water quality and microbial assemblages varied significantly across space and time, and most taxa were rare. Lakes were moderately saline and circumneutral; Archeans were not prevalent. Richness also varied by catchment. Microbial assemblages correlated to environmental variables, and no one variable was consistently significant, spatially or temporally. Study lakes were dominated by 'core' taxa exhibiting temporal turnover likely driven by geography, water quality and interspecific competition, and the presence of water chemistry associated with an artificial aquifer likely influenced microbial community composition. Pit lakes are deceptively complex aquatic ecosystems that host equally complex pelagic microbial communities. This research established links between microbial assemblages and environmental variables in pit lakes and determined core communities; the first steps towards developing a monitoring program using microbes.
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Project description:ImportanceOpen burn pits have commonly been used for waste disposal by the US military but have not been systematically investigated as an independent risk factor for headache disorders.ObjectiveTo evaluate the association between exposure to open burn pits and incidence of headache and migraine.Design, setting, and participantsThis retrospective cohort study used data from the Veterans Health Administration Headache Cohort along with data from the US Department of Defense and the Airborne Hazards and Open Burn Pit (AH&OBP) Registry to assess registry participants with potential exposure to open burn pits in the Veterans Health Administration from April 1, 2014, through October 31, 2022. Participants were included by linking data from the AH&OBP Registry to their US Department of Defense and Veterans Health Administration electronic health records. Those with preexisting headache were removed from the analytic sample. The analysis was conducted between November 1, 2022, and January 31, 2024.ExposureOpen burn pit exposure composite variables based on the registry questionnaire were examined, specifically being near open burn pits, days near open burn pits, and having open burn pit duties.Main outcomes and measuresPrimary incident outcomes included medically diagnosed headache disorders and medically diagnosed migraine.ResultsThe analytic sample included 247 583 veterans (mean [SD] age, 27.9 [7.7] years; 222 498 [89.9%] male). After covariates were controlled for at baseline, participants who were near an open burn pit with open burn pit duties had the highest adjusted odds of medically diagnosed headache disorders (adjusted odds ratio [AOR], 1.59; 95% CI, 1.46-1.74), migraine (AOR, 1.60; 95% CI, 1.43-1.79), and self-reported disabling migraine (AOR, 1.93; 95% CI, 1.69-2.20) compared with those without exposure. The 2 highest quartiles of cumulative burn pit exposure (290-448 days and >448 days) had significantly higher adjusted odds of medically diagnosed headache (290-448 days: AOR, 1.20; 95% CI, 1.09-1.31; >448 days: AOR, 1.55; 95% CI, 1.41-1.70) and migraine (290-448 days: AOR, 1.19; 95% CI, 1.07-1.34; >448 days: AOR, 1.48; 95% CI, 1.32-1.65).Conclusions and relevanceIn this cohort study, a dose-dependent association existed between open burn pit exposure and medically diagnosed headache and migraine. These new data identify potentially important associations between open burn bit exposure and new-onset headache among service personnel as well as a possible health condition that may be encountered more frequently in Veterans Health Administration facilities during mandatory screening for military exposures.
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Project description:BACKGROUND: Contrasting biological, chemical and hydrogeological analyses highlights the fundamental processes that shape different environments. Generating and interpreting the biological sequence data was a costly and time-consuming process in defining an environment. Here we have used pyrosequencing, a rapid and relatively inexpensive sequencing technology, to generate environmental genome sequences from two sites in the Soudan Mine, Minnesota, USA. These sites were adjacent to each other, but differed significantly in chemistry and hydrogeology. RESULTS: Comparisons of the microbes and the subsystems identified in the two samples highlighted important differences in metabolic potential in each environment. The microbes were performing distinct biochemistry on the available substrates, and subsystems such as carbon utilization, iron acquisition mechanisms, nitrogen assimilation, and respiratory pathways separated the two communities. Although the correlation between much of the microbial metabolism occurring and the geochemical conditions from which the samples were isolated could be explained, the reason for the presence of many pathways in these environments remains to be determined. Despite being physically close, these two communities were markedly different from each other. In addition, the communities were also completely different from other microbial communities sequenced to date. CONCLUSION: We anticipate that pyrosequencing will be widely used to sequence environmental samples because of the speed, cost, and technical advantages. Furthermore, subsystem comparisons rapidly identify the important metabolisms employed by the microbes in different environments.
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Project description:In general, exploitation of rock materials, such as limestone or granite exploitation, can cause serious damage to the environment near a mine area. With economic development and the ever-increasing demand for ore resources, mining activities have induced very serious environmental issues in China. Therefore, environmental restoration work around mines in China is urgently required. This study explores the Chuankou open-pit limestone quarry in Tongchuan City, Shaanxi Province, Northwest China, as the engineering case. The environmental issues caused by over 40 years of limestone exploitation, including land degradation, land occupation, dust pollution and potential geological disasters, were investigated. Combining the characteristics of this quarry with a summary of previous studies on environmental restoration work, this paper proposes a novel and systematic method that was comprehensively carried out through engineering and revegetation measures. The engineering measure, that is, the construction of an artificial slope by using local abandoned construction materials, solved the environmental problems in this quarry and provided site conditions favourable for revegetation. The revegetation measure restored the local ecosystem. This method provides both a new idea for the sustainable development of a mining area and a useful reference for analogous engineering cases.
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