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1.
Nathaniel D. McClure IV 《Environmental Geology》1985,7(1-2):109-124
The enactment of the National Environmental Policy Act (NEPA) had a substantial influence on the manner in which the Tennessee-Tombigbee
Waterway (Tenn-Tom) was constructed The interdisciplinary approach, including a board of outside consultants functioning as
environmental advisors, played a valuable role toward meeting the objectives of minimizing adverse impacts and maximizing
the positive environmental aspects Several of the key environmental issues associated with the Tenn-Tom are addressed and
the findings are presented impacts addressed include aquifer drawdown, waterlogging, water quality, interbasin transfer, mixing
of species, endangered species, erosion, sedimentation, and loss of wildlife habitat Additional discussion is also presented
to explain the findings and place the identified impacts into perspective While implementation of the Tenn-Tom involved losses
and resource tradeoffs, measures have been incorporated into the project to mitigate for significant resource losses The evaluation,
planning, and design process for the Tenn-Tom can serve as a model approach for compliance with NEPA and other environmental
statutes 相似文献
2.
A method is described for analyzing nanogram quantities of chlorinated hydrocarbons from 1-1 samples of seawater. Seawater samples are pumped through a copper column containing a mixture by weight of 5% activated carbon powder, 10% MgO and 85% refined diatomaceous earth. The chlorinated hydrocarbons in the seawater are adsorbed or trapped on the column and subsequently eluted with 30% benzene in acetone (v/v) for analysis by gas-liquid chromatography.This procedure was used to analyze chlorinated hydrocarbon levels in samples collected off the southern California coast. We suggest that anthropogenic chlorinated hydrocarbons can be used for the investigation of large-scale ocean currents and mixing processes. 相似文献
3.
This study investigates the extent to which people's views on the causes and preventability of earthquake damage might be influenced by their degree of exposure to hazard as well as what information they have been given about the hazard. The results show that the provision of hazard zoning information influences judgements on preventability and causes of damage, but this effect depends on the degree of hazard faced by residents. In low hazard zones, information leads to the view that causes are manageable, whereas in high hazard zones information may induce a degree of fatalism. The use of public information in risk management needs to take into account the degree of risk faced by the recipients. 相似文献
4.
Matthew J. Spittal Frank H. Walkey John McClure Richard J. Siegert Kimberley E. Ballantyne 《Natural Hazards》2006,39(1):15-29
Preparedness is a key dependent variable in many studies examining people’s response to disasters such as earthquakes. A feature
of many studies on this issue, however, is the lack of attention given to psychometric issues when constructing measures of
preparedness. With regard to earthquake preparation, for example, many studies could be greatly improved by the use of a valid
and reliable measure of preparedness. This research developed such a measure that assessed both low-level preparedness, such
as having an emergency kit, and high-level preparedness, such as altering home structures to mitigate damage. Studies of Wellington
(New Zealand) residents using two samples totalling n=652 showed that 23 items measuring these different aspects of earthquake preparation could be combined into a reliable, valid,
unifactorial scale. This brief scale should have utility in multivariate studies of earthquake preparation, either as a dependent
variable, where preparation is the outcome variable of primary interest, or as one of several independent variables, where
preparation and other measures predict another outcome variable. 相似文献
5.
Gianni Gallello Mirco Ramacciotti Oreto García-Puchol Simon Chenery Alfredo Cortell-Nicolau MARíA Luisa Cervera Agustin Diez-Castillo Agustín Pastor Sarah B. McClure 《Boreas: An International Journal of Quaternary Research》2021,50(4):1190-1208
This study investigates the stratigraphical sequence of Cocina Cave (Spain) employing and testing for the first time the capability of rare earth elements as markers of human activities in caves. Located in Dos Aguas (Valencian Community, Spain), Cocina Cave is characterized by the presence of several Holocene archaeological deposits from the final Mesolithic to the present day and is a pivotal site for understanding the socio-ecological dynamics of the last hunter-gatherer inhabitants of the Iberian Peninsula and the transition to pastoral and agricultural economies in the Western Mediterranean. However, the identification of strata from particular time-periods in the cave is often difficult due to the homogeneity of layers, the poor archaeological record in some strata and the presence of severe disturbance phenomena. The methodological approach of this study consisted of cross-referencing rare earth elements and other chemical markers with the archaeological stratigraphical interpretation, in an attempt to not only support the identification of the anthropic contribution to the formation of Cocina Cave strata, but also to characterize and confirm different natural and occupational episodes, particularly those associated with hunter-gatherer, early agriculturalist, and shepherd activities. Sediments were collected from different excavation areas and analysed for major elements, trace elements, rare earth elements (REE), soil organic matter (SOM) amounts and pH. Multivariate statistics were employed to group samples according to their elemental profile, and these were then compared to the archaeological temporal interpretation. The obtained results showed that REE amount and fractionation geochemical processes were regulated by carbonates, phosphates and pH. The use of REE as markers was particularly useful as their concentrations and their calculated ratios and anomaly distributions were demonstrated to be highly consistent with the archaeological stratigraphical interpretation. 相似文献
6.
Although Quaternary marine terraces have been reported from eastern Saudi Arabia at heights of up to 150 m, unambiguous shoreline deposits could be identified only within 3 m of present-day High Water and close to the modern shoreline. Unaltered aragonitic mollusc shells from five such deposits yielded 14C ages of 3700–6000 yr B.P. Comparison of their elevations with those of coeval deposits on the Zagros coast of Iran demonstrates the relative stability of the Saudi shore of the Gulf during the late Holocene. 相似文献
7.
We investigate the estimation of interfacial areas, curvatures, and common curve lengths in multiphase porous medium systems. Algorithms are developed to obtain estimates of these quantities based upon a variety of potential data sources and estimation approaches. The accuracy of the derived approximations are evaluated as a function of the data type and resolution of the data. The methods advanced improve upon standard approaches now in use and show excellent accuracy at resolutions on the order of five lattice points per minimum radius of curvature of the object being resolved. Finally, we suggest a promising class of extensions that could lead to further improvements in the accuracy of such methods. 相似文献
8.
As part of the Wychwood Project in West Oxfordshire, England, aerial photography and historic maps are being used to reconstruct landscape change in the former medieval Royal Hunting Forest of Wychwood. An important objective of the project is to stimulate local interest in Wychwood and promote understanding of its evolution, thereby encouraging the support of stakeholders in the design of future landscapes. The parish of Leafield was selected to develop and test a method for reconstructing and visualising past and present landscapes to present to the public for evaluation and comparison. Leafield contains fine examples of both early and late enclosure landscapes and underwent large-scale disafforestation following the Enclosure Act of 1856. Ordnance Survey (O.S.) 1:10000 Landform Panorama contour data were used to create a digital elevation model (DEM) of the parish using ArcView 3D Analyst, enabling the user to create perspective views of the landscape from any height and viewing angle. Contemporary aerial photography was scanned and geo-rectified to create an overlay for 'draping' onto the DEM. Historical maps provided the reference for modifying the aerial photography using the PaintShop Pro graphics package. This paper presents and reviews the results and compares the method with other techniques, including VRML. 相似文献
9.
The marine record shows that over the last 350 ka Northern Hemisphere ice sheet volumes have fluctuated widely and only on rare short occasions have they been reduced to the present interglacial state. The fluctuations are well synchronized with hemispheric average summer insolation variations of 20 ka periodicity caused by changing orbital parameters. The development of a model which explains the varied amplitudes of the fluctuations and is consistent with the geological record embodies the following arguments: The transition from an interglacial state like today's to a glacial state is initiated when a summer insolation deficit causes a southerly extension of the North Atlantic-Arctic pack ice to 60°N latitude. The extension alters the subpolar low pressure patterns and thus causes a southward diversion of the European Gulf Stream flow. It also produces an enhanced warm West Greenland current. This current causes open seas as far north as Baffin Bay which provides moisture for rapid northern Laurentide ice sheet growth. After several glacial fluctuations driven by insolation variations, the southern Laurentide ice front may reach an extreme extension. This diverts the westerlies and the Gulf Stream thus weakening a dominant subpolar North Atlantic gyre and consequently producing a prolonged cutoff of the West Greenland current and a reduction of high latitude glacial precipitation. The subsequent high insolation can then melt back the eastern pack ice and restore the northern European Gulf Stream. This warms the high latitudes for a time sufficient to melt the continental ice, thus causing the transition back to the interglacial state.An analysis of the record in the context of model suggests that the threshold deficit in average summer insolation that is required to initiate major glacial growth is influenced by the cooling effect of the Greenland ice cap on the seas to the east. The threshold level under conditions like today's is found to lie between ?7 and ?17 ly/day relative to the present. This threshold will not be crossed for at least 54 millenia due to an interval of smaller orbital eccentricity. Probable melting of the Greenland ice cap about 30 ka AP would ensure the extension of the present interglacial beyond 120 ka AP. 相似文献
10.
Two high value species, yellowtail kingfish (Seriola lalandi) and hāpuku (groper, Polyprion oxygeneios), have been identified as suitable new candidates for New Zealand aquaculture. This paper reviews the research by NIWA and collaborators conducted to test the biological, technological and economic feasibility of farming these two species. NIWA now has the capability to produce sufficient kingfish fingerlings per year to meet the needs of the early stages of an industry. Advances in hāpuku aquaculture have also been significant, from spawning in captivity through to the selection of juveniles for improved growth. Recently, the first spawning of captive hāpuku F1 broodstock and production of F2 eggs, larvae and juveniles was achieved. Although hāpuku larval survival remains variable, the ability to close the life cycle, and the availability of domesticated broodstock, provide a significant step forward and increase the chances of this species being commercially farmed. 相似文献