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871.
Pete Campana John Knox Andrew Grundstein John Dowd 《Journal of the American Water Resources Association》2012,48(2):379-390
Campana, Pete, John Knox, Andrew Grundstein, and John Dowd, 2012. The 2007‐2009 Drought in Athens, Georgia, United States: A Climatological Analysis and an Assessment of Future Water Availability. Journal of the American Water Resources Association (JAWRA) 48(2): 379‐390. DOI: 10.1111/j.1752‐1688.2011.00619.x Abstract: Population growth and development in many regions of the world increase the demand for water and vulnerability to water shortages. Our research provides a case study of how population growth can augment the severity of a drought. During 2007‐2009, a drought event that caused extreme societal impacts occurred in the Athens, Georgia region (defined as Clarke, Barrow, Oconee, and Jackson counties). An examination of drought indices and precipitation records indicates that conditions were severe, but not worse than during the 1925‐1927, 1954‐1956, and 1985‐1987 drought events. A drought of similar length to the 2007‐2009 drought would be expected to occur approximately every 25 years. Streamflow analysis shows that discharge levels in area streams were at a record low during 2007 before water restrictions were implemented, because of greater water usage caused by recent population increases. These population increases, combined with a lack of water conservation, led to severe water shortages in the Athens region during late 2007. Only after per capita usage decreased did water resources last despite continuing drought conditions through 2009. Retaining mitigation strategies and withdrawal levels such as seen during the height of the drought will be an essential strategy to prevent water shortages during future extreme drought events. The key mitigation strategy, independent local action to restrict water use in advance of state‐level restrictions, is now prohibited by Georgia State Law. 相似文献
872.
Martin W. Doyle F. Douglas Shields 《Journal of the American Water Resources Association》2012,48(3):494-509
Doyle, Martin W. and F. Douglas Shields, 2012. Compensatory Mitigation for Streams Under the Clean Water Act: Reassessing Science and Redirecting Policy. Journal of the American Water Resources Association (JAWRA) 48(3): 494-509. DOI: 10.1111/j.1752-1688.2011.00631.x Abstract: Current stream restoration science is not adequate to assume high rates of success in recovering ecosystem functional integrity. The physical scale of most stream restoration projects is insufficient because watershed land use controls ambient water quality and hydrology, and land use surrounding many restoration projects at the time of their construction, or in the future, do not provide sufficient conditions for functional integrity recovery. Reach scale channel restoration or modification has limited benefits within the broader landscape context. Physical habitat variables are often the basis for indicating success, but are now increasingly seen as poor surrogates for actual biological function; the assumption “if you build it they will come” lacks support of empirical studies. If stream restoration is to play a continued role in compensatory mitigation under the United States Clean Water Act, then significant policy changes are needed to adapt to the limitations of restoration science and the social environment under which most projects are constructed. When used for compensatory mitigation, stream restoration should be held to effectiveness standards for actual and measurable physical, chemical, or biological functional improvement. To achieve improved mitigation results, greater flexibility may be required for the location and funding of restoration projects, the size of projects, and the restoration process itself. 相似文献
873.
Martin W. Doyle 《Journal of the American Water Resources Association》2012,48(4):820-837
Doyle, Martin W., 2012. America’s Rivers and the American Experiment. Journal of the American Water Resources Association (JAWRA) 48(4): 820‐837. DOI: 10.1111/j.1752‐1688.2012.00652.x Abstract: America’s rivers are managed, over long periods of time, based on the most basic ideologies of the United States (U.S.) government. An essential notion of the U.S. government, and thus a necessity of river management, is governing as experiment. This leads to three necessary characteristics of river management: (1) adapting management practices based on experience and thus creating management and agency structures that are highly malleable and that can change directions, (2) overlapping of management roles and responsibilities between agencies which includes intentional redundancy and interagency competition, and (3) federalism — the devolution of responsibilities between national, state, and other unit governments (e.g., municipalities, counties). While these characteristics are often criticized as inefficient, in fact they have provided a surprisingly effective system for river management that has responded to the needs of society at different times and in different places. A key question for river and water resource managers is whether this particular system, so initially unappealing, is best able to meet the future needs of the U.S. 相似文献
874.
《Journal of Environmental Policy & Planning》2012,14(3):233-244
International emissions trading under the Kyoto Protocol or an alternative international regime need a registration system to prevent the creation of fake emission permits. We suggest a two-tier system consisting of an International Registry (IR) and a set of national registries. National registries have to adhere to a set of minimum standards. The IR maintains accounts for countries and private entities. The latter would thus be ensured against expropriation. We suggest that permits should become fungible across all Kyoto Mechanisms, and are allocated a serial number to allow tracking. The IR should collect fees for adaptation and administration. It should also be charged with reallocation of emission budgets owing to various causes, enforcing of eventual caps, and discounting of permits owing to non-compliance. We discuss the registration process and a timetable for the set-up of the registries. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
875.
Between 1985 and 1995, fertility in Eastern Europe declined from 2.2 children per woman to merely 1.5 on region-average. Previous
research has emphasized mainly the economic turmoil during transition or the influx of new ideas regarding fertility and family
relations. This article suggests that applying a risk management perspective on fertility patterns may put additional light
on the reasons behind the fertility decline in post-communist Europe. The complexity of modern social systems has made people
increasingly dependent on the state for risk evaluation and risk management. The article formulates the hypothesis that transition
itself disrupted the mental models that helped people to navigate among the risks associated to having and raising children.
Left to their own devices, women in Eastern Europe became more inclined to postpone childbirth or discard this option altogether. 相似文献
876.
The term governance describes the multitude of actors and processes that lead to collectively binding decisions. The term
risk governance translates the core principles of governance to the context of risk-related policy making. We aim to delineate
some basic lessons from the insights of the other articles in this special issue for our understanding of risk governance.
Risk governance provides a conceptual as well as normative basis for how to cope with uncertain, complex and/or ambiguous
risks. We propose to synthesize the breadth of the articles in this special issue by suggesting some changes to the risk governance
framework proposed by the International Risk Governance Council (IRGC) and adding some insights to its analytical and normative
implications. 相似文献
877.
Garcia M Scheffczyk A Garcia T Römbke J 《Environmental pollution (Barking, Essex : 1987)》2011,159(2):398-400
Plant Protection Products can affect soil organisms and thus might have negative impacts on soil functions. Little research has been performed on their impact on tropical soils. Therefore, the effects of the insecticide lambda-Cyhalothrin on earthworms were evaluated in acute and chronic laboratory tests modified for tropical conditions, i.e. at selected temperatures (20 and 28 °C) and with two strains (temperate and tropical) of the compost worm Eisenia fetida. The insecticide was spiked in two natural soils, in OECD artificial soil and a newly developed tropical artificial soil. The effects of lambda-Cyhalothrin did rarely vary in the same soil at tropical (LC50: 68.5-229 mg a.i./kg dry weight (DW); EC50: 54.2-60.2 mg a.i./kg DW) and temperate (LC50: 99.8-140 mg a.i./kg DW; EC50: 37.4-44.5 mg a.i./kg DW) temperatures. In tests with tropical soils and high temperature, effect values differed by up to a factor of ten. 相似文献
878.
Naile JE Khim JS Wang T Wan Y Luo W Hu W Jiao W Park J Ryu J Hong S Jones PD Lu Y Giesy JP 《Environmental pollution (Barking, Essex : 1987)》2011,159(4):907-917
Polychlorinated-dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) were measured in soils and sediments from the Yellow Sea region. Korean soils and sediments mostly contained detectable PCDD/Fs and showed a widespread distribution among locations. Soil and sedimentary PCDD/Fs from China were comparable to or less than those in Korea. The patterns of relative concentrations of individual congeners in soils were different between the two countries, but similar in sediments. Sources of PCDD/Fs in China and Korea were found to be independent of each other and their distributions reflected matrix-dependent accumulation. Spatial distribution indicated some point sources in Korea while Chinese sources were more widespread and diffuse. PCDD/Fs measured in the coastal areas of the Yellow Sea were comparable to or less than those previously reported in for eastern Asia. However, ∑TEQs in soils and sediments were near to or, in some cases exceeded environmental quality guidelines. 相似文献
879.
In vitro and in vivo approaches for the measurement of oral bioavailability of lead (Pb) in contaminated soils: a review 总被引:3,自引:0,他引:3
Zia MH Codling EE Scheckel KG Chaney RL 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2320-2327
We reviewed the published evidence of lead (Pb) contamination of urban soils, soil Pb risk to children through hand-to-mouth activity, reduction of soil Pb bioavailability due to soil amendments, and methods to assess bioaccessibility which correlate with bioavailability of soil Pb. Feeding tests have shown that urban soils may have much lower Pb bioavailability than previously assumed. Hence bioavailability of soil Pb is the important measure for protection of public health, not total soil Pb. Chemical extraction tests (Pb bioaccessibility) have been developed which are well correlated with the results of bioavailability tests; application of these tests can save money and time compared with feeding tests. Recent findings have revealed that fractional bioaccessibility (bioaccessible compared to total) of Pb in urban soils is only 5-10% of total soil Pb, far lower than the 60% as bioavailable as food-Pb presumed by U.S.-EPA (30% absolute bioavailability used in IEUBK model). 相似文献
880.
Screening of pharmaceuticals and hormones at the regional scale, in surface and groundwaters intended to human consumption 总被引:6,自引:0,他引:6
As part of a regional screening to evaluate the risk, for the health of populations, to certain classes of emerging substances, several families of pharmaceuticals and hormones were looked for in waters intended to drinking. Thus, 52 substances were investigated in 71 surface waters and 70 groundwaters. Results indicate that no water was free of pollutants, regardless of its origin (surface or groundwater) and the season of collect. The pharmaceuticals most frequently detected and with the highest concentration levels were salicylic acid, carbamazepine and acetaminophen. Among hormones, testosterone, androstenedione and progesterone were detected in almost all the samples. Globally the groundwaters were less contaminated than surface waters in regards pharmaceuticals frequencies and levels. On the other side, androgens and progestagens were present with comparable frequencies and levels in both compartments. The risk linked to the presence of these substances on human health is discussed. 相似文献