77 research outputs found
Tracing sources and fate of zinc in a mining-impacted river catchment: insights from flow measurements, synoptic sampling, and zinc isotopes
This paper reports on the comprehensive monitoring of the Rookhope Burn catchment in the
Weardale valley, northern Pennines (Uk), which has been subject to lead, zinc, and fluorspar mining for
over two centuries. Zinc is the major contaminant in surface waters, exceeding the Environmental Quality
standard value for salmonid fish. synoptic flow monitoring and water sampling have been carried
out, including both inflow and instream sampling points along the Rookhope Burn, with the purpose
of tracing both point and diffuse sources of Zn throughout the catchment. The Zn load profile suggests
an important role for Zn-rich groundwater contributions to the stream bed and has also established the
existence of Zn sinks. Evidence from hyporheic zone sampling suggests Zn reaction or surface complexation
with Mn oxide surfaces forming on stream bed sediments as a potential mechanism responsible
for the observed metal attenuation. Current work is focused on testing the potential of Zn isotopes to
fingerprint sources and pathways of Zn in the aquatic system. Preliminary results show significant variation
in the stream water Zn isotopic signature from the headwaters to the base of the catchment
The Hyporheic Zone
This chapter introduces the key concepts of the hyporheic zone. It considers the research context in terms of the Water Framework Directive and the breadth of literature associated with the hyporheic zone. The interplay between hydrological, chemical and biological processes is explained, and a range of different approaches to field sampling and monitoring are described. A framework for considering the factors contributing to the conceptualisation of the hyporheic zone is presented, with an emphasis on the importance of understanding streambed sediments and their architecture to assess hydraulic functioning and modelling of the hyporheic zone. The hyporheic zone in karst catchments is also given specific consideration. Returning to the theme of linked hydrological, biological and chemical processes, the results of two case studies demonstrate the value of integrating hydrological measurements with geochemistry in order to elucidate hyporheic zone functioning
Conceptual models of Witbank coalfield, South Africa : Earth observation for monitoring and observing environmental and societal impacts of mineral resources Exploration and Exploitation, CEC FP7 Project EO-MINERS, Deliverable D3.1-2
This report presents the work undertaken as part of the EO MINERS WP3 - project task 3.1. âSite Specific Available Data Collectionâ and develops a conceptual site model (CSM) for the Witbank coalfield, South Africa and for Bank Colliery, South Africa which has been selected to demonstrate the automated time-lapse electrical resistivity monitoring (ALERT) system of a leachate plume.
The report presents the available information regarding known apparent environmental impacts. This information is derived from a literature review and from the findings of surveys conducted as part of work package WP1. Additionally the principal socio-economic impacts defined by WP1 have been presented. It goes on to consider the environmental factors that influence the transport of contaminants from the source to the exposed individuals or environmental receptors, through identified potential exposure pathways, describing the source- pathway-receptor interactions through two conceptual site models (CSMs), one for the Witbank Coal Mining region and the other for Bank Colliery. A CSM for the socio-economic impacts has also been attempted.
Examining the CSM results in the identification of data gaps and information needed for a full environmental assessment of mining in Witbank and provides the rational for EO selection.
Present and past coal mining in Witbank is associated with a number of environmental problems, including: acid mine drainage (AMD) derived from the oxidation of pyrite in the coal, specific contaminants including potentially harmful metals and arsenic (which occur in the mining environment and in dust associated with both the operation of the mines and the transport of the coal) and ground gases that are both naturally occurring and a consequence of self-combustion of the coal and waste dumps. A wide range of ecological and socio-economic impacts result from these impacts, including the impacts on land value and agriculture. Additional problems include ground subsidence due to pillar collapse, which has further consequences on the migration of AMD and self combustion.
The CSMs have been used to identify the key direct or indirect indicators of mining impacts and an assessment of the potential to monitor these using Earth Observatory (EO) assessments has been made. The majority of the indicators lend themselves to EO assessment in one form or another (Table 7)
Catchment-scale assessments of the effects of abandoned metal mines on groundwater quality and stream ecology
This paper presents an overview of a British Geological Survey catchment-scale research project designed to quantify catchment-derived metal loading on surface water quality. This work is focused on the Rookhope Burn, a tributary of the River Wear in the North Pennines, UK. The river has been identified in the Water Framework Directive (WFD) River Basin Management report as being at risk of failing to achieve Good Status due to mines and minewater pressures. Although geologically relatively simple, the catchment is hydrogeologically complex in that it comprises an area of entrenched karst, characterised by Lower Carboniferous Limestone exposed in the base of valleys overlain by Namurian strata, comprising interbedded shales, sandstones and limestones, which are capped by drained blanket peat. Metal loadings in this catchment result from lead and zinc mineralization and its historic exploitation and processing, which have resulted in both point source and diffuse impacts within the catchment. There have been three main phases of research: (i) collection of hydrological and water chemistry data to enable loading and mass balance calculations to be undertaken; (ii) development of a conceptual understanding of the hydrology and hydrogeology of the catchment, and (iii) application of the hydrological understanding to more recent baseline monitoring of ecological impacts. This work has identified previously unreported mine and groundwater contributions to the catchment, which may have significant implications for the design of remedial measures in the catchment
Limitations on the role of the hyporheic zone in chromium natural attenuation in a contaminated urban stream
The urban hyporheic zone may offer natural attenuation potential for contaminants. This potential is contaminant-specific and may be spatially and temporally variable. The aim of this study was the assessment of the natural attenuation potential of the hyporheic zone of an urban stream receiving hexavalent chromium (Cr)-rich effluents from the historical land disposal of chromite ore processing residue (COPR) in Glasgow, Scotland. The evidence based approach involved the use of a network of multilevel piezometers for best capturing potential anoxic field conditions and fine-scale spatial gradients in solute concentrations of surface water and porewater. In-situ porewater sampling was integrated with sediment sampling and reach-scale monitoring of stream water quality. The results show a sharp decrease of total dissolved (filtered <0.45 ÎŒm) Cr concentrations at the surface water â sediment boundary in all profiles, from Cr mean values of 1100 ÎŒg lâ1 in surface water to 5 ÎŒg lâ1 in porewater. Chromium speciation analysis indicates that no Cr(VI) was detectable in the neutral pH, moderately reducing porewater, while it was the dominant species in surface water. Evidence of historical COPR detrital grains contributed to the total Cr concentrations (size fraction <150 ÎŒm) up to 8800 mg kgâ1 in the streambed sediment. The abundance in the porewater of Fe (mean value = 1700 ÎŒg lâ1), mainly as Fe(II), a natural electron donor for Cr(VI) reduction to Cr(III), indicates a high natural attenuation potential of the hyporheic zone for downwelling dissolved Cr, through Cr(VI) reduction to Cr(III) and the formation of Cr(III) solids of low solubility. Authigenic Cr-rich rims on particles also documented active Cr precipitation from solution in the fine sediments. Large short-term changes of stream stage and stream water composition were not reflected in the hyporheic conservative (chloride) and reactive solute composition. This result indicates only limited surface water infiltration and suggests that small advective exchange might limit the effectiveness of the hyporheic zone for enhancing Cr surface water quality at the reach-scale. This is supported by further evidence from preliminary surface water quality synoptic sampling which shows only moderate to low downstream decrease in surface water Cr concentrations. The surface water investigation needs to be supported by combined water quality-flow monitoring and to be extended to a wider range of temporal and spatial scales to corroborate the reach-scale findings
Landslide Detection in Real-Time Social Media Image Streams
Lack of global data inventories obstructs scientific modeling of and response
to landslide hazards which are oftentimes deadly and costly. To remedy this
limitation, new approaches suggest solutions based on citizen science that
requires active participation. However, as a non-traditional data source,
social media has been increasingly used in many disaster response and
management studies in recent years. Inspired by this trend, we propose to
capitalize on social media data to mine landslide-related information
automatically with the help of artificial intelligence (AI) techniques.
Specifically, we develop a state-of-the-art computer vision model to detect
landslides in social media image streams in real time. To that end, we create a
large landslide image dataset labeled by experts and conduct extensive model
training experiments. The experimental results indicate that the proposed model
can be deployed in an online fashion to support global landslide susceptibility
maps and emergency response
Mapping ground instability in areas of geotechnical infrastructure using satellite InSAR and Small UAV Surveying: a case study in Northern Ireland
Satellite Interferometric Synthetic Aperture Radar (InSAR), geological data and Small Unmanned Aerial Vehicle (SUAV) surveying was used to enhance our understanding of ground movement at five areas of interest in Northern Ireland. In total 68 ERS-1/2 images 1992â2000 were processed with the Small Baseline Subset (SBAS) InSAR technique to derive the baseline ground instability scenario of key areas of interest for five stakeholders: TransportNI, Northern Ireland Railways, Department for the Economy, Arup, and Belfast City Council. These stakeholders require monitoring of ground deformation across either their geotechnical infrastructure (i.e., embankments, cuttings, engineered fills and earth retaining structures) or assessment of subsidence risk as a result of abandoned mine workings, using the most efficient, cost-effective methods, with a view to minimising and managing risk to their businesses. The InSAR results provided an overview of the extent and magnitude of ground deformation for a 3000 km2 region, including the key sites of the disused salt mines in Carrickfergus, the BelfastâBangor railway line, Throne Bend and Ligoniel Park in Belfast, Straidkilly and Garron Point along the Antrim Coast Road, plus other urbanised areas in and around Belfast. Tailored SUAV campaigns with a X8 airframe and generation of very high resolution ortho-photographs and a 3D surface model via the Structure from Motion (SfM) approach at Maiden Mount salt mine collapse in Carrickfergus in 2016 and 2017 also demonstrate the benefits of very high resolution surveying technologies to detect localised deformation and indicators of ground instabilit
Revalidation Technique on Landslide Susceptibility Modelling: An Approach to Local Level Disaster Risk Management in Kuala Lumpur, Malaysia
Landslide susceptibility modelling in tropical climates is hindered by incomplete inventory due to rapid development and natural processes that obliterate field evidence, making validation a challenge. Susceptibility modelling was conducted in Kuala Lumpur, Malaysia using a new spatial partitioning technique for cross-validation. This involved a series of two alternating east-west linear zones, where the first zone served as the training dataset and the second zone was the test dataset, and vice versa. The results show that the susceptibility models have good compatibility with the selected landslide conditioning factors and high predictive accuracy. The model with the highest area under curve (AUC) values (SRC = 0.92, PRC = 0.90) was submitted to the City Council of Kuala Lumpur for land use planning and development control. Rainfall-induced landslides are prominent within the study area, especially during the monsoon period. An extreme rainfall event in December 2021 that triggered 122 landslides provided an opportunity to conduct retrospective validation of the model; the high predictive capability (AUC of PRC = 0.93) was reaffirmed. The findings proved that retrospective validation is vital for landslide susceptibility modelling, especially where the inventory is not of the best quality. This is to encourage wider usage and acceptance among end users, especially decision-makers in cities, to support disaster risk management in a changing climate
Revisiting the upper Visean mud mounds from Derbyshire (UK): the role of brachiopods in their growth
Several brachiopod-rich mud mounds occur in the upper Visean (Brigantian) of the Derbyshire Carbonate Platform succession in UK. The re-evaluation of the lithofacies architecture of a Derbyshire mud mound complex, developed in an intraplatform middle-ramp environment, led to the recognition of three lithofacies associations: (a) a 10 m thick basal unit of automicrite boundstone with siliceous sponge spicules and brachiopodâbryozoan packstone to wackestone beds; (b) a 10 m thick, 250 m wide, lens-shaped, convex-up massive core of clotted peloidal micrite and fenestellid bryozoan boundstone with sponge spicules; (c) inclined brachiopodâbryozoanâcrinoid packstone flank beds. In the mud mound complex core, most of the carbonate mud with clotted peloidal and structureless micrite fabric is the result of biologically induced and influenced in-situ precipitation processes (automicrite). Brachiopods are not, as previously thought, limited to storm-scoured âpocketsâ in the mud mound complex core but are abundant and diverse in all lithofacies and lived on the irregular mud mound complex surface concentrating in depressions sustained by automicrite boundstone and the growth of bryozoans and sponges. The upper Visean Derbyshire mud mounds are, thus, representatives of a newly defined fenestellid bryozoanâbrachiopodâsiliceous sponge mud mound category, occurring in various middleâupper Visean Western European sites, a sub-type of the fenestellid bryozoanâcrinoidâbrachiopod Type 3 buildups of Bridges et al. (1995). These mud mounds, and other types of brachiopod-rich buildups, developed in carbonate platform settings between fair-weather and storm wave base, in dysphotic environments with dispersed food resources during the Visean. Brachiopod mud mound colonisation was favoured by moderate water depth, availability of food resources, and diverse substrates
A Drosophila Model of HPV E6-Induced Malignancy Reveals Essential Roles for Magi and the Insulin Receptor
We would like to thank Drs. Vivian Budnik, Herbert JĂ€ckle, Larry Reiter, Andreas Wodarz, for generously providing reagents, the Bloomington Drosophila Stock Center, and the Confocal facility at University of Oklahoma (supported by a Major Research Instrumentation grant DBI-1126578 from the National Science Foundation to B. Zhang, R. Hewes, B. Holt, D. McCauley, and M. Nanny) for the use of the confocal microscope. We also thank Dr. David McCauley and Dr. Randall Hewes for discussions and sharing equipment. We thank the Developmental Studies Hybridoma Bank (University of Iowa, Department of Biology, Iowa City) for antibodies.Author Summary Human papillomaviruses (HPV) are the causative agents of cervical cancer, one of the leading causes of cancer death in women worldwide. The E6 oncoprotein encoded by HPV has been implicated in the progression of primary tumors to metastatic disease and we have developed a new model in the fruit fly (Drosophila melanogaster) to study the cellular effects of E6. The E6 protein recruits an E3 ubiquitin ligase (UBE3A) to induce the degradation of a number of cellular proteins, including members of the MAGUK family of scaffolding proteins that control the structure and polarity of epithelial cells: Dlg, Scribble and Magi. Expression of E6 and human UBE3A in the wing and eye of Drosophila disrupted these tissues. Similar to human cells we found that Drosophila Magi was a major E6 degradation target and that overexpression of Magi rescued the tissue disruption. However, Drosophila p53 was not degraded by E6/UBE3A, making our fly model potentially useful for studying the p53-independent activities of the E6+UBE3A complex. When we paired E6 expression with oncogenic proteins, including activated Ras, we observed that epithelia were transformed into mesechymal-like cells that left the epithelium and spread through the body. As a test of the potential of our system, we carried out a pilot genetic screen and identified the insulin receptor as a strong modulator of the E6-mediated disruption of Drosophila tissues. Therefore, we have developed a new system and approach to help us better understand the mechanisms that underlie how HPV infection leads to cell transformation and cancer.Yeshttp://www.plospathogens.org/static/editorial#pee
- âŠ