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21.
Gorazd Žibret 《Environmental Geology》2008,56(1):189-196
The research shows that in the Celje area (Slovenia), the historical anthropogenical emissions are 1,712 tons of Zn and 9.1 tons
of Cd. For Zn, this value represents approximately 0.3% of the total Zn production in that area. Close to the former zinc
smelting plant, the “Zn precipitation” has been estimated to be up to 0.036 mm. The 100-year Zn production left behind a heavily
contaminated area with maximum concentrations of Zn of up to 5.6% in attic dust and 0.85% in the soil, and 456 mg/kg of Cd
in attic dust and 59.1 mg/kg in the soil. The calculation of historical emissions is based on the data of heavy metals concentration
in the attic dust at 98 sampling points and on the data from 19 measurement sites of the weight of total monthly air deposit.
The main idea behind determining past emissions is that when the weight of the deposited dust on a small area is multiplied
by the concentration of the element in that area, the mass of the polluter which has been transported to the place of interest
by air can be calculated. If we sum up all the weight over the whole geochemical anomaly, we get the quantity of historical
emissions. 相似文献
22.
With recent changes in the ways that state agencies are implementing their environmental policies, the line between public and private is becoming increasingly blurred. This includes shifts from state-led implementation of environmental policies to conservation plans that are implemented and managed by multi-sectoral networks of governments, the private sector and environmental non-governmental organizations (ENGOs). This paper examines land trusts as private conservation initiatives that become part of neoliberal governance arrangements and partnerships that challenge our conceptions of environmental preservation and democratic participation. The paper starts with an examination of the concept of neoliberalized environmental governance. Next, it addresses the shifting social constructions of property and land in the context of protecting large scale ecosystems. Through a case study of the extension of new environmental governance arrangements on the Oak Ridges Moraine in Ontario, we examine the relationships that have formed between different levels of the state and environmental non-governmental organizations. Finally, we analyze the expansion of land trusts and private conservation initiatives that are predicated on private land ownership and the commodification of nature, the emerging discourses and practices of private conservation, and how these are implicated in the privatization and neoliberalization of nature. 相似文献
23.
David P. Bacon Nash’at N. Ahmad Thomas J. Dunn Michael C. Monteith Ananthakrishna Sarma 《Natural Hazards》2008,44(3):317-327
By definition, a crisis is a situation that requires assistance to be managed. Hence, response to a crisis involves the merging
of local and non-local emergency response personnel. In this situation, it is critical that each participant: (1) know the
roles and responsibilities of each of the other participants; (2) know the capabilities of each of the participants; and (3)
have a common basis for action. For many types of natural disasters, this entails having a common operational picture of the unfolding events, including detailed information on the weather, both current and forecasted, that may impact on either
the emergency itself or on response activities. The Consequences Assessment Tool Set (CATS) is a comprehensive package of
hazard prediction models and casualty and damage assessment tools that provides a linkage between a modeled or observed effect
and the attendant consequences for populations, infrastructure, and resources, and, hence, provides the common operational
picture for emergency response. The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric
simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies
with numerical weather prediction to provide specific weather analysis and forecast capability that can be merged into the
geographic information system framework of CATS. This paper documents the problem of emergency response as an end-to-end system
and presents the integrated CATS–OMEGA system as a prototype of such a system that has been used successfully in a number
of different situations. 相似文献
24.
Prakash C. Sinha Indu Jain Neetu Bhardwaj Ambarukhana D. Rao Shishir K. Dube 《Natural Hazards》2008,45(3):413-427
The Orissa coast of India is one of the most vulnerable regions of extreme sea levels associated with severe tropical cyclones.
There was extensive loss of life and property due to the October 1999 super cyclone, which devastated large part of the Orissa
coast. The shallow nature of the head bay, presence of a large number of deltas formed by major rivers of Orissa such as Mahanadi
and Dhamra, and high tidal range are responsible for storm surge flooding in the region. Specifically, rising and falling
tidal phases influence the height, duration, and arrival time of peak surge along the coast. The objective of the present
study is to evaluate the tide-surge interaction during the 1999 Orissa cyclone by using nonlinear vertically integrated numerical
models. The pure tidal solution for the head bay region of the Bay of Bengal provides the initial condition for the fine resolution
nested grid Orissa model. However, the feedback from the Orissa model does not affect the head bay model as the study provides
a one-way interaction. Numerical experiments are performed to study the tide-surge interaction by considering various relative
phases of the tidal waves with the surge-wave produced by 1999 Orissa cyclone. The comparison, although utilizing only the
limited estimates of tidal data, appears adequate to assert that the principal features are reproduced correctly. 相似文献
25.
Two algorithms for in-situ detection and identification of vertical free convective and double-diffusive flows in groundwater
monitoring wells or boreholes are proposed. With one algorithm the causes (driving forces) and with the other one the effects
(convection or double-diffusion) of vertical transport processes can be detected based on geophysical borehole measurements
in the water column. Five density-driven flow processes are identified: thermal, solutal, and thermosolutal convection leading
to an equalization, as well as saltfingers and diffusive layering leading to an intensification of a vertical density gradient.
The occurrence of density-driven transport processes could be proven in many groundwater monitoring wells and boreholes; especially
shallow sections of boreholes or groundwater monitoring wells are affected dramatically by such vertical flows. Deep sections
are also impaired as the critical threshold for the onset of a density-driven flow is considerably low. In monitoring wells
or boreholes, several sections with different types of density-driven vertical flows may exist at the same time. Results from
experimental investigations in a medium-scale testing facility with high aspect ratio (height/radius = 19) and from numerical
modeling of a water column agree well with paramters of in-situ detected convection cells. 相似文献
26.
27.
In this study, we investigate two internal wave generation methods in numerical modeling of time-dependent equations for water wave propagation, i.e., delta source function method and source term addition method, the latter of which has been called the line source method in literatures. We derive delta source functions for the Boussinesq-type equations and extended mild-slope equations. By applying the fractional step splitting method, we show that the delta source function method is equivalent to the source term addition method employing the energy velocity. This suggests that the energy velocity should be used rather than the phase velocity for the transport of incident wave energy in the source term addition method. Finally, the performance of the delta source function method is verified by accurately generating nonlinear cnoidal waves as well as linear waves for horizontally one-dimensional cases. 相似文献
28.
We develop techniques of numerical wave generation in the time-dependent extended mild-slope equations of Suh et al. [1997. Time-dependent equations for wave propagation on rapidly varying topography. Coastal Engineering 32, 91–117] and Lee et al. [2003. Extended mild-slope equation for random waves. Coastal Engineering 48, 277–287] for random waves using a source function method. Numerical results for both regular and irregular waves in one and two horizontal dimensions show that the wave heights and the frequency spectra are properly reproduced. The waves that pass through the wave generation region do not cause any numerical disturbances, showing usefulness of the source function method in avoiding re-reflection problems at the offshore boundary. 相似文献
29.
30.
Information systems developed for different applications within the environmental domain have common characteristics, which can potentially be abstracted for sharing and reuse of design and software modules. This article presents an approach to designing for reuse by abstracting commonalities in the design of a Marine Information System (MIS), facilitating data management in a prototype operational monitoring, forecasting, and management system for the North Atlantic and the Nordic Seas. A detailed study of the requirements and data analysis was carried out, and Object-Oriented Technology (OOT) is employed to encapsulate abstractions and to promote reuse of code and design. This article identifies the Object-Oriented Frameworks (OOFW) required to build the MIS. It also provides guidelines to environmental scientists for restructuring legacy software and employing modern programming techniques. 相似文献