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1.
The spatial distribution of the concentrations of heavy metals Cd, Pb, Zn and Cu were studied for contaminated wetlands located by industrial centres and villages influenced by anthropogenic contamination in the Russian Arctic. For comparison, non-contaminated wetlands were also studied in neighbouring areas. Samples were collected during the period 1977–1994 and included: (a) water, (b) particulate matter, (c) bottom sediments, (d) hydric soils and (e) hummock bog peat and polygonal bog peat. For impacted wetlands, the observed ranges for the concentrations of Cd, Pb, Zn, and Cu in water were 0.12–0.8, 0.9–2.5, 2.4–15 and 16–34 μg l−1, respectively. For (b)- (e) the corresponding values were [1.2–5.4; 24–37; 120–320; 80–116]; [6.4–17; 34–59; 240–570; 115–280]; [10–32; 57–78; 315–480; 87–350] and [5.1–53; 51–150; 125–520; 80–440] mg/kg, dry wt, respectively. The metal concentrations were up to 1000 times higher than background levels determined for non-contaminated wetlands in the Russian Arctic. The contaminants appear to be a direct result of localized anthropogenic activity, arising primarily from geoprospecting, the oil and coal industry, and domestic waste.  相似文献   
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An international demonstration (RD&D) project for ocean storage of radioactive wastes should be proposed, to study the feasibility of the concept of ocean storage of nuclear waste. This international project should utilize the scientific, engineering and technical capabilities of selected universities, oceanographic institutions, NGOs and industries. This project would need to be an independent (non-governmental) study, utilizing the capabilities of selected universities, oceanographic institutions, environmental NGOs (Non-Governmental Organizations) and industries. Scientists and engineers first need to conduct an engineering, environmental, and economic feasibility study of the concept. The goal of the project would be to determine if ocean-based storage reduced the risks to the environment and public health to a greater degree than land-based storage. This would require comparing the risks and factors involved and making the data and information available to anyone, anywhere, anytime on the internet. The mere presence of an investigation of the ocean storage option could facilitate scientific and engineering competition between the two options, could subsequently reduce environmental and public risks and provide better protection and cost benefits in the system utilized. One of the primary concerns of the scientific community would be related to the sensitivity and precision of the monitoring of individaul containers on the ocean bottom. An advantage of the land-based option is that if there is a release, its presence could be detected at very low levels and be contained in the storage facility. On the ocean bottom, a release from a container might not be easily detected due to dispersion. Therefore the containment system would have to be a system within a system with monitoring between the two providing greater protection. Ocean storage may have greater technical and political hurdles than land-based options, but it may provide greater protection over time, because it negates the threat of terrorism, it therefore merit further study. In the future if the use of nuclear energy and nuclear wastes increases, the global society could benefit from this international project, because it could reduce environmental and public health risks and promote energy independence.  相似文献   
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Trace organic (chlorinated pesticides, PCBs, PAHs and dioxins/furans) and trace metal concentrations were measured in surficial sediment and biological tissues (i.e., worms, crustaceans, bivalve molluscs, and fish livers) collected from the Russian Arctic. Total DDT, chlordane, PCB and PAH concentrations ranged from ND to 1.2, ND to <0.1, ND to 1.5 and <20-810 ng g(-1), respectively, in a suite of 40 surficial sediment samples from the Kara Sea and the adjacent Ob and Yenisey Rivers. High sedimentary concentrations of contaminants were found in the lower part of the Yenisey River below the salt wedge. Total dioxins/furans were analysed in a subset of 20 sediment samples and ranged from 1.4 to 410 pg g(-1). The highest trace organic contaminant concentrations were found in organisms, particularly fish livers. Concentrations as high as 89 ng g(-1) chlordane; 1010 ng g(-1) total DDTs; 460 ng g(-1) total PCBs; and 1110 ng g(-1) total PAH, were detected. A subset of 11 tissue samples was analysed for dioxins and furans with total concentrations ranging from 12 to 61 pg g(-1). Concentrations of many trace organic and metal contaminants in the Kara Sea appear to originate from riverine sources and atmospheric transport from more temperate areas. Most organic contaminant concentrations in sediments were low; however, contaminants are being concentrated in organisms and may pose a health hazard for inhabitants of coastal villages.  相似文献   
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The recent Diplomatic Conference held (1-5 October 2001) by the International Maritime Organization (IMO) in London adopted the Draft Convention prepared by The Marine Environmental Protection Committee (MEPC) of IMO for the "Control of Harmful Anti-fouling Systems for Ships." The convention has been developed to immediately ban the use of Tributyltin (TBT) globally in anti-fouling paints to "protect the marine environment". The ban on TBT has come about because TBT has detrimental effects on non-target marine organisms. In November 1999, IMO agreed that a treaty be developed by the MEPC to ensure a ban on the application of TBT based anti-fouling paints by 1 January 2003, and a ban on the use of TBT by 1 January 2008. At the meeting surious concern was expressed by some experts for the need to identify in the treaty the necessary regulatory language for: (1) the "safe" removal, treatment, and disposal of marine anti-foulants deemed "harmful" by the treaty and (2) who is liable for the future dredging and disposal of TBT-contaminated port and harbor sediments--to also "protect the marine environment". The requirement for "safe" removal and disposal was incorporated at MEPC 46 as Article 5 in the treaty, without it shipyards complying with existing national and local discharge regulations (most have none for discharge of TBT) could inadvertently release more TBT to ports and harbors in the five-year compliance period than has been leached from ships (hulls) in the past 40 years to the same waters. Virginia is the only State in the US that regulates the discharge to below 50 ng/l (50 parts per trillion). However, the liability for the future dredging and disposal costs of TBT-contaminated port and harbor sediments has not been addressed.  相似文献   
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The proposed MTB is a process to expedite the implementation of international standards and regulations, and the subsequent testing, certification, and regulatory approval of new ballast water treatment ("control") technologies. This would expedite their acceptance in the global marketplace and reduce risks of shipowners following international regulation. The cost to test and evaluate and certify new ballast water treatment technologies for the global marketplace has been estimated to be less than US $1 per day per ship. It is time for the shipping industry, national regulatory bodies, and IMO to endorse the concept of the MTB and for the shipping industry to support a proactive cost-saving solution for sustainable shipping and protecting the environment from unwanted invasions of aquatic species with their potential negative impacts.  相似文献   
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Long-term records of biological data are extremely valuable for documenting ecosystem changes, for differentiating natural changes from those caused by humans, and for generating and analyzing testable hypotheses. Long-term sampling, however, is generally discouraged by a variety of institutional disincentives, so that today such records are uncommon. We discuss approaches for overcoming these disincentives through improved research planning and design, including clearera priori definition of management and regulatory actions and information needs, more rigorous adherence to hypothesis formulation and testing, and proper spatial and temporal scaling in sampling. We distinguish between prospective study design, in which the foregoing elements are essential for coast-effectiveness, and retrospective analysis, which relies on reconstruction of long-term records from existing data sets. We demonstrate the great value of retrospective analysis of encountered data, and argue for renewed attention to archival of data sets with documented data quality, interacalibration and documentation of methodologies, and long-term storage of samples for future analysis. Such practices are essential to ensure the quality of long-term records that are reconstructed for retrospective examination of new hypotheses in the future.  相似文献   
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The number of people living in wildfire-prone wildland–urban interface (WUI) communities is on the rise. However, no prior study has investigated wildfire-induced residential relocation from WUI areas after a major fire event. To provide insight into the association between sociodemographic and sociopsychological characteristics and wildfire-related intention to move, we use data from a survey of WUI residents in Boulder and Larimer counties, Colorado. The data were collected 2 months after the devastating Fourmile Canyon fire destroyed 169 homes and burned more than 6,000 acres of public and private land. Although this study is working with a small migrant sample, logistic regression models demonstrate that survey respondents intending to move in relation to wildfire incidence do not differ sociodemographically from their nonmigrant counterparts. They do, however, show significantly higher levels of risk perception. Investigating destination choices shows a preference for short-distance moves.  相似文献   
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Background concentrations of Cd, Pb, Zn and Cu were studied for wetlands from pristine regions of the Russian Arctic: Severnaya Zemlya Archipelago, Vrangel Island, Arctic deserts and tundra of the North Taimyr Peninsula, Byrranga Mountainous Area, tundra zone of Mid-Siberia, North-East Siberia, Far North-East, and Amguemo-Anadyr Mountainous Area. These wetland regions were known to be relatively remote and isolated, with little human population and no local industry. Samples were collected during the period 1976–1993 and included: (a) snow and thaw water, (b) particulate matter, (c) bottom sediments, (d) hydric organo-mineral deposits and hydric soils, (e) polygonal bog peat and sedge-moss peat. Observed ranges for the background concentrations of Cd, Pb, Zn, and Cu in water were 0.001–0.15, 0.02–0.36, 0.05–2.9 and 0.23–6.2 μg l−1 respectively. For (b)–(e) the corresponding values were [0.04–0.46; 1.3–41; 8.6–190; 0.7–63]; [0.05 0.99; 1.5–49; 2.5–153; 2.4–55]; [0.05–0.96; 1.7–44; 2.2–154; 2.0–82] and [0.03–0.83; 1.3–31; 2.1–124; 1.7–68] mg kg−1, dry wt, respectively. Although full assessment of the pristine nature of the wetlands was not possible due to the limited data available, the observed metal concentrations reflect natural geochemical background levels and influence from localized minor ore-deposits present for some regions. In general, there was no evidence of impact from remote industrial regions of the Russian Arctic.  相似文献   
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