A5062426859- Geochemistry and Geologic Mapping
- Research on scale insects
- Geological and Geochemical Analysis
- Insect-Plant Interactions and Control
- Fecal contamination and water quality
- Hymenoptera taxonomy and phylogeny
- earthquake and tectonic studies
- Hemiptera Insect Studies
- Soil and Water Nutrient Dynamics
- Soil erosion and sediment transport
- Selenium in Biological Systems
- Hydrocarbon exploration and reservoir analysis
- Geophysical and Geoelectrical Methods
- Environmental Justice and Health Disparities
- Mine drainage and remediation techniques
- Agricultural Economics and Policy
- Agriculture Sustainability and Environmental Impact
- Wastewater Treatment and Reuse
- Soil Carbon and Nitrogen Dynamics
- Urban Stormwater Management Solutions
- Land Use and Ecosystem Services
- Water resources management and optimization
- Constructed Wetlands for Wastewater Treatment
- Moringa oleifera research and applications
- Water Treatment and Disinfection
University of the Witwatersrand
2022-2023
National Museum Wales
2004-2022
Rothamsted Research
2010-2020
Cardiff University
2007-2010
Okehampton Hospital
2009
University of Huddersfield
2003-2004
Barrick Gold (Canada)
2002
Queen's University
1965-1995
Kingston Health Sciences Centre
1977-1994
General Department of Preventive Medicine
1986
Alien species are the principal threat to conservation of Galápagos Islands, but little is known about status nonindigenous insects and their effects on biota. Currently, 463 alien insect have probably been introduced Galápagos, an increase 186 unintentional introductions since inventory in 1998. now constitute 23% total fauna. Six be invasive a biota: two fire ant wasps, scale insect, ectoparasitic dipteran. The ecological impacts remaining unknown, making prioritization action for...
Pipe-shaped zones of altered rock containing disseminated and stockwork vein mineralization underlie each the several Archean volcanogenic Cu-Zn ore lenses at Millenbach mine. The rocks have been metamorphosed first to hornblende hornfels assemblages, then retrograded greenschist facies but metamorphism has not significantly affected bulk composition rocks. alteration pipes show a distinct mineralogical zoning in which core zone either anthophyllite-bearing assemblages or massive chlorite...
Emissions of nitrous oxide (N2O) from soils grazed grasslands have large uncertainty due to the great spatial variability excreta deposition, resulting in heterogeneous distribution nutrients. The contribution urine labile N pool, much larger than that dung, is likely be a major source emissions so efforts determine N2O emission factors (EFs) and dung deposition are required improve inventory greenhouse gases agriculture. We investigated effect application cattle at different times grazing...
Regional metamorphism, ranging in grade from the subgreenschist-facies to greenschist–amphibolite-facies transition, affects all Archean supracrustal rocks (>2677 Ma) Rouyn–Noranda area. Contact metamorphic minerals associated with posttectonic Preissac–Lacorne batholith (2643 show no evidence of a regional retrograde event. Accordingly, age metamorphism can be bracketed between 2677 and 2643 Ma. Three reaction isograds were mapped metabasites, dividing low-grade into three zones:...
The MacTung deposit is the largest of economically important contact metasomatic deposits northeastern Canadian Cordillera which are characterized by ore element assemblage W-Cu(Zn). occur within thermal aureoles Late Cretaceous felsic intrusions were emplaced into a dominantly pelitic sequence along eastern margin Selwyn basin. mineralization occurs in skarn bodies comprised pyroxene, amphibole, garnet, pyrrhotite, biotite, clinozoisite, plagioclase, and quartz, with amounts scheelite...
The world-class breccia-, stockwork-, and vein-hosted epithermal Au-Ag-Cu deposits of the central Andean El Indio-Pascua belt, latitudes 29°20' to 30°30' S, were emplaced between 6.2 9.4 Ma, immediately beneath shoulders an actively uplifting north-south tectonic block along axis Cordillera Principal. Pascua-Lama, Veladero, Indio, Tambo districts are hosted by largely felsic volcanic units late Oligocene-Early Miocene Late Paleozoic age, but associated with small hypabyssal bodies dacitic...
The debate over the suitability of molecular biological methods for enumeration regulatory microbial parameters (e.g. Faecal Indicator Organisms [FIOs]) in bathing waters versus use traditional culture-based is current interest to regulators and science community. Culture-based require a 24–48 hour turn-around time from receipt at laboratory reporting, whilst quantitative tools provide more rapid assay (approximately 2–3 h). Traditional culturing are therefore often viewed as slow...
Dairy farming generates large volumes of liquid manure (slurry), which is ultimately recycled to agricultural land as a valuable source plant nutrients. Different methods slurry application exist; some spread the sward surface whereas others deliver under and into soil, thus helping reduce greenhouse gas (GHG) emissions from agriculture. The aim this study was investigate impact two (surface broadcast versus shallow injection) on survival faecal indicator organisms (FIOs) delivered via dairy...
Abstract Mineral equilibria in the system CaO–MgO–Al 2 O 3 –SiO –H provide a basis for mapping of four reaction isograds and one bathograd low‐pressure transition from subgreenschist to greenschist facies. Most Matachewan area Abitibi greenstone belt is lower‐pressure bathozone, as indicated by widespread occurrences subassemblage Prh–Chl. The higher‐pressure bathozone two Pmp–Act–Ep–Qtz, but these samples displaced anomalously low pressure high Fe content coexisting minerals. This...
The Sigma mine at Val d9Or, Quebec, in the Abitibi belt is typical of vein-type gold deposits Archcan greenstone belts. Although relative timing mineralization with respect to magmatism, metamorphism, deformation, and hydrothermal events well documented, precise isotopic age constraints have, until recently, been lacking. This paper presents results a 40 Ar/ 39 Ar dating study Davidson-Tisdale deposit belt. In mine, dates on metamorphic amphibole indicate that regional which predates vein...
The prediction of microbial concentrations and loads in receiving waters is a key requirement for informing policy decisions order to safeguard human health. However, modelling the fate transfer dynamics faecally derived microorganisms at different spatial scales poses considerable challenge research community. objective this paper critically evaluate complexities associated uncertainties attributed development models assessing agriculturally pollution watercourses. A series issues with...
A laboratory assay for comparative characterization of various faecal matrices with respect to indicator organism (FIO) release using, artificial rain water.Fresh sheep and beef-cattle faeces, dairy cattle slurry beef farm yard manure (FYM) were collected from commercial units in south-west England applied 20 randomized 1 m(2) plots established on permanent grassland. Representative samples each matrix (n = 5) four occasions over 16 days. One gram sample was transferred a sterile vial which...
Solubilities of sphalerite (ZnS) and galena (PbS) were determined at 300° to 500°C 1000 bars total pressure in a chemical environment buffered by silicate mineral equilibria. Chloride solutions muscovite-bearing assemblages characteristic hydrothermal wall-rock alteration used; weak acidities temperature therefore involved. The metal concentrations encountered tended be higher than those observed high bisulfide-H2S systems neutral weakly basic pH used most previous experimentation; the...
Selenium (Se) is a non-metallic trace element essential for normal cellular function, which has been linked with reduced risk of cancer, cardiovascular disease, cognitive decline and thyroid disease in humans. Se deficiency livestock associated white muscle retained placenta, ill-thrift mastitis. Where status or bioavailability from the soil plants poor, rely on supplemental their diets predominantly as either sodium selenite (inorganic form) selenised-yeast (organic form). As lactic acid...