Barium and strontium uptake into larval protoconchs and statoliths of the marine neogastropod Kelletia kelletii     

Danielle C. Zacherl  Georges Paradis 《Geochimica et cosmochimica acta》2003,67(21):4091-4099

The trace elemental composition of calcified larval hard parts may serve as useful tags of natal origin for invertebrate population studies. We examine whether the trace metal barium (Ba) deposits into the calcium carbonate matrix of molluscan larval statolith and protoconch in proportion to seawater Ba concentration at two temperatures (11.5 and 17°C). We also examine strontium (Sr) uptake as a function of temperature. Using encapsulated larvae of the marine gastropod, Kelletia kelletii, reared in the laboratory under controlled conditions, we demonstrate a significant inverse effect of temperature and a positive effect of seawater Ba/Ca ratio on Ba incorporation into larval carbonates. Ba/Ca partition coefficients (D_Ba) in protoconch were 1.13 at 11.4°C and 0.88 at 17.1°C, while D_Ba in larval statolith measured 1.58 at 11.4°C and 1.29 at 17.1°C. Strontium incorporation into statoliths is also inversely affected by temperature, but there was a significant positive effect of temperature on Sr incorporation into protoconch. These data suggest larval statoliths and protoconchs can meaningfully record variation in seawater physical and chemical properties, and, hence, have potential as natural tags of natal origin.  相似文献   

Spatio‐Temporal Object‐Oriented Data Model for Disaggregate Travel Behavior     

Ali Frihida  Danielle J. Marceau  Marius Thriault 《Transactions in GIS》2002,6(3):277-294

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Neutralization of sulfuric acid solutions by calcite dissolution and the application to anoxic limestone drain design     

Danielle M.C. Huminicki  J. Donald Rimstidt 《Applied Geochemistry》2008

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Clinopyroxene composition as a method of identification of the magmatic affinities of paleo-volcanic series   总被引：3，自引：0，他引：3  

Jacques Leterrier  René C. Maury  Pierre Thonon  Danielle Girard  Michèle Marchal 《Earth and Planetary Science Letters》1982,59(1):139-154

Uranium contents and²³⁴U/²³⁸U activity ratios have been determined for groundwaters from the Lincolnshire Limestone artesian aquifer in eastern England. Changes in the quantitative and isotopic chemistry of the dissolved uranium are explained in terms of a mixing model involving the rapidly moving fissure water and much older water stored in the pore system of this oolitic limestone. The western part of the aquifer, closest to recharge, is dominated by oxidising groundwaters which then enter a reducing zone towards the east, where there is an abrupt decrease in Eh and the chlorinity of the groundwaters begins to increase. Uranium contents in the oxidising zone range from 0.7 to 3.4 μg kg^?1 and²³⁴U/²³⁸U activity ratio of this dissolved uranium is close to unity, the equilibrium value. The uranium content decreases abruptly when the grounwaaters enter the reducing zone, averaging 0.04 μg kg^?1 east of the oxidation/reduction barrier. Simultaneously with the decrease in uranium content, there is an increase in²³⁴U/²³⁸U activity ratio and this ratio increases to a maximum within 7 km of the oxidation/reduction barrier. This increase in activity ratio is attributed to enhanced²³⁴U solution due to²³⁴Th recoil from uraniferous fissure surfaces east of the oxidising zone. The activity ratio of dissolved uranium in the ancient pore waters could in principle reach high values due to²³⁴Th recoil from the oolith surfaces. However, the activity ratio actually declines further east and this can only be explained as a consequence of mixing with pore waters in which the uranium activity ratio is closer to equilibrium.²³⁴Th recoil from the oolith surfaces has probably been inhibited by sealing of the uranium-bearing surfaces in the process of oolith cementation.  相似文献   

Social Applications of Geographical Information Systems: technical tools for social innovation     

Danielle Taylor  Jarrod Lange 《The Australian geographer》2016,47(4):417-433

ABSTRACT

The establishment of the National Key Centre for Social Applications of Geographical Information Systems (GIS) in 1995, under the directorship of Professor Graeme Hugo, was a turning point in the use of GIS in Australia. The field of GIS, previously dominated by environmental applications, now broadened its focus to include populations, services and the interactions between people and the environment. Social applications of GIS offered a unique opportunity to make service planning, reporting, funding allocations and research both smarter and fairer. Geography and geographic relationships as implemented in GIS became the integrating platform for social spatial information, invigorating social research, planning and policy. A key strength of this approach, recognised by Professor Hugo, was the ability to ‘put people back into the planning process’. Further to being an integrating platform, GIS also offered the ability to generate new information and knowledge, which could facilitate evidence-based decision making. This paper focuses in particular on providing a written record of the development of the Accessibility/Remoteness Index of Australia (ARIA) suite of spatial accessibility indices. The lasting legacy and continued relevance of this work in social applications of GIS is also reviewed in this paper, with reference to key examples of how social research and planning in Australia have been made both smarter and fairer through the contributions of Professor Hugo and his team.  相似文献   

Deposition and provenance of the Early Pleistocene Siliceous Member in Westbury Cave,Somerset, England     

Neil F. Adams  Ian Candy  Danielle C. Schreve  René W. Barendregt 《Proceedings of the Geologists' Association. Geologists' Association》2019,130(2):210-226

The Early Pleistocene is an important interval in the Quaternary period as a time not only of climatic and environmental change, but also of key events in human evolution. However, knowledge of this period in northwest Europe is hampered by the limited extent of deposits of this age. Westbury Cave in the Mendip Hills of Somerset preserves an understudied example of fossil-bearing Early Pleistocene sediments, with rare potential to inform our understanding of British Early Pleistocene stratigraphy and landscape evolution outside the East Anglian Crag Basin. This study identifies the processes responsible for deposition of the Early Pleistocene Siliceous Member in Westbury Cave, thereby aiding taphonomic and palaeoenvironmental interpretations of associated fossil assemblages. New excavations revealed over ten metres of Siliceous Member stratigraphy, dominated by fine-grained silts/clays with interbedded sands and gravels, interpreted as being deposited within a subterranean lake or flooded conduit with fluvial input. All sediments sampled were reversely magnetised and are assigned to the Matuyama Reversed Chron. Lithological analysis of gravel clasts revealed variable components of durable non-local and non-durable local clasts. Gravels containing the latter are interpreted as distal talus slope deposits, and those lacking non-durable lithologies as stream or flood deposits. However, it remains unclear from available data whether apparently non-local clasts were sourced from long distance or stem from a more local, now denuded catchment. Siliceous Member bio- and magnetostratigraphy suggest that deposition occurred late in the Early Pleistocene, a period apparently otherwise unrepresented in the UK.  相似文献   

Arrest Rates during Natural Resource Development: Drilling,Drinking and Disorderly Conduct in the Marcellus Shale Region     

Danielle C. Rhubart  Kathryn J. Brasier 《社会与自然资源》2019,32(6):675-692

Increased criminal activity has been linked to rapid natural resource development, particularly in rural areas. These “boomtowns” often experience rapid population growth, resulting in “social disruption”. This research examines one component of social disruption, crime, in the context of unconventional energy development in Pennsylvania. We employ quantitative longitudinal methods to examine the association between county-level arrest rates for four types of minor crimes and unconventional natural gas well density in Pennsylvania from 2005 to 2014 controlling for demographic and socioeconomic variables. Results indicate that well density is positively associated with driving under the influence and disorderly conduct arrest rates, but is not associated with arrest rates for drug abuse violations or public drunkenness. Findings suggest the need to look beyond broad categories of criminal activity to particular types of crime related to energy development, and to what extent these indicate broader patterns of social disruption.  相似文献   

Ignoring market failure in quota leasing?     

Evelyn Pinkerton  Danielle N. Edwards 《Marine Policy》2010

This short communication is, in part, a response to the Bruce Turris' rejoinder (Marine Policy…2010) to Pinkerton et al., The elephant in the room: The hidden costs of leasing individual transferable fishing quotas (Marine Policy, July 2009). In responding to this article on the unacknowledged problems of unregulated and even unrecorded leasing of individual transferable fishing quotas (ITQs), Turris illustrated the point of the original article well by minimizing the status of leasing as a major influence leading to problems with the fishery: an elephant in the room. Turris focused instead on relatively small and less relevant details, misrepresented the argument, and largely ignored or skirted our discussion of the absent structural conditions important for open competition and efficient outcomes. This response addresses several of his concerns, elaborates on some of the initial points in the original article and contributes some new ones.  相似文献   

Methane sources,sinks and fluxes in a temperate tidal Lagoon: The Arcachon lagoon (SW France)     

Jonathan Deborde  Pierre Anschutz  Frédéric Guérin  Dominique Poirier  Danielle Marty  Guy Boucher  Gérard Thouzeau  Mathieu Canton  Gwenaël Abril 《Estuarine, Coastal and Shelf Science》2010

The Arcachon lagoon is a 156 km² temperate mesotidal lagoon dominated by tidal flats (66% of the surface area). The methane (CH₄) sources, sinks and fluxes were estimated from water and pore water concentrations, from chamber flux measurements at the sediment–air (low tide), sediment–water and water–air (high tide) interfaces, and from potential oxidation and production rate measurements in sediments. CH₄ concentrations in waters were maximal (500–1000 nmol l⁻¹) in river waters and in tidal creeks at low tide, and minimal in the lagoon at high tide (<50 nmol l⁻¹). The major CH₄ sources are continental waters and the tidal pumping of sediment pore waters at low tide. Methanogenesis occurred in the tidal flat sediments, in which pore water concentrations were relatively high (2.5–8.0 μmol l⁻¹). Nevertheless, the sediment was a minor CH₄ source for the water column and the atmosphere because of a high degree of anaerobic and aerobic CH₄ oxidation in sediments. Atmospheric CH₄ fluxes at high and low tide were low compared to freshwater wetlands. Temperate tidal lagoons appear to be very minor contributor of CH₄ to global atmosphere and to open ocean.  相似文献   

The elephant in the room: The hidden costs of leasing individual transferable fishing quotas     

Evelyn Pinkerton  Danielle N. Edwards 《Marine Policy》2009

Despite the increasingly positive reviews of individual transferable quotas (ITQs), few studies have considered how quota leasing activities can reduce the economic benefits to society and to fishermen operating under the ITQ fisheries system. This analysis reveals negative economic impacts of ITQs previously overlooked by examining the extent of quota leasing and the relationship between the catch value, the cost of fishing, and the quota lease price in the BC halibut fishery, long considered a poster child for ITQs. Findings challenge assumptions of economic theory used to promote the benefits of ITQs.  相似文献