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571.
A preliminary investigation and evaluation of the thallium environmental impacts of the unmined Xiangquan thallium-only deposit in Hexian,China 总被引:7,自引:0,他引:7
Taofa Zhou Yu Fan Feng Yuan David Cooke Xin Zhang Liangjun Li 《Environmental Geology》2008,54(1):131-145
The Xiangquan Thallium-only deposit in Hexian, east China is a newly found near-surface and unmined shallow-seated thallium
deposit. The 250t Tl deposit is hosted in Lower Ordovician Lunshan Group as lenticular and confined by northeast F1, F2 faults.
The metallic minerals are dominated by pyrite, more than 95% Tl occurs in pyrite as tiny individual grains or as ‘‘invisible
thallium”. Tl and other trace elements pollution in ecosystems such as soils, surface and ground waters and water sediments,
plants and crops, and animal and human beings in Xiangquan near the Tl ore deposit have been investigated and evaluated. Results
show that Tl as well as As and Sb in ecosystems in Xiangquan around the deposit have enriched, they came from Tl-pyrite in
the ore bodies and in the parent rocks of weathered soils on top of the ore bodies and went into the nearby ecosystems through
weathering, leaching and dissolving. In 2 km2 around the Xiaolongwang Mountain where the Tl ore deposit seated, soils, vegetables, crops have been polluted or heavily
polluted by Tl, As and Sb. Farmlands near the ore body are not fit to grow vegetables and crops. Thermal Spring water in Xiangquan
town and pond water close to the Tl deposit are not potable. Tl also enriches in human hair and urinate of villagers who live
close to the Tl deposit. Even through the Tl-only deposit has put clear environmental impacts on the local environment and
ecosystems around it, no serious consequences of Tl pollution have so far taken place due to unmining of the Tl deposit as
well as the screen effect of the silicficious breccia cap on top of it. All this work adds new knowledge to understand Tl
behavior in unmined Tl deposit, and also benefit to the local environmental protection and the future mineral resources exploration. 相似文献
572.
The use of scenarios as the basis for combined assessment of climate change mitigation and adaptation 总被引:1,自引:0,他引:1
Detlef P. van Vuuren Morna IsaacZbigniew W. Kundzewicz Nigel ArnellTerry Barker Patrick CriquiFrans Berkhout Henk HilderinkJochen Hinkel Andries HofAlban Kitous Tom KramReinhard Mechler Serban Scrieciu 《Global Environmental Change》2011,21(2):575-591
Scenarios are used to explore the consequences of different adaptation and mitigation strategies under uncertainty. In this paper, two scenarios are used to explore developments with (1) no mitigation leading to an increase of global mean temperature of 4 °C by 2100 and (2) an ambitious mitigation strategy leading to 2 °C increase by 2100. For the second scenario, uncertainties in the climate system imply that a global mean temperature increase of 3 °C or more cannot be ruled out. Our analysis shows that, in many cases, adaptation and mitigation are not trade-offs but supplements. For example, the number of people exposed to increased water resource stress due to climate change can be substantially reduced in the mitigation scenario, but adaptation will still be required for the remaining large numbers of people exposed to increased stress. Another example is sea level rise, for which, from a global and purely monetary perspective, adaptation (up to 2100) seems more effective than mitigation. From the perspective of poorer and small island countries, however, stringent mitigation is necessary to keep risks at manageable levels. For agriculture, only a scenario based on a combination of adaptation and mitigation is able to avoid serious climate change impacts. 相似文献
573.
旅游业的环境影响综合评价与对策 总被引:3,自引:0,他引:3
旅游业对自然环境有正反两方面的影响。反面影响包括对水体和大气环境的影响,对动植物的影响,对土壤和沙丘的侵蚀,以及影响审美。正面影响包括建立自然保护区,保护海洋、植被、湿地,促进连际土地开发和教育民众。促进旅游业永续发展的对策有:对旅游业进行选择;对旅游区进行环境规划;对旅游业的环境影响进行实验追踪,建立综合性模式研究旅游业的累积环境影响。 相似文献
574.
575.
While it is generally asserted that those countries who have contributed least to anthropogenic climate change are most vulnerable to its adverse impacts some recently developed indices of vulnerability to climate change come to a different conclusion. Confirmation or rejection of this assertion is complicated by the lack of an agreed metric for measuring countries’ vulnerability to climate change and by conflicting interpretations of vulnerability. This paper presents a comprehensive semi-quantitative analysis of the disparity between countries’ responsibility for climate change, their capability to act and assist, and their vulnerability to climate change for four climate-sensitive sectors based on a broad range of disaggregated vulnerability indicators. This analysis finds a double inequity between responsibility and capability on the one hand and the vulnerability of food security, human health, and coastal populations on the other. This double inequity is robust across alternative indicator choices and interpretations of vulnerability. The main cause for the higher vulnerability of poor nations who have generally contributed little to climate change is their lower adaptive capacity. In addition, the biophysical sensitivity and socio-economic exposure of poor nations to climate impacts on food security and human health generally exceeds that of wealthier nations. No definite statement can be made on the inequity associated with climate impacts on water supply due to large uncertainties about future changes in regional water availability and to conflicting indicators of current water scarcity. The robust double inequity between responsibility and vulnerability for most climate-sensitive sectors strengthens the moral case for financial and technical assistance from those countries most responsible for climate change to those countries most vulnerable to its adverse impacts. However, the complex and geographically heterogeneous patterns of vulnerability factors for different climate-sensitive sectors suggest that the allocation of international adaptation funds to developing countries should be guided by sector-specific or hazard-specific criteria despite repeated requests from participants in international climate negotiations to develop a generic index of countries’ vulnerability to climate change. 相似文献
576.
N. Bhandari 《Journal of Earth System Science》1998,107(4):251-263
The boundary horizons of the Cretaceous-Tertiary (Um Sohryngkew River section, Meghalaya and Anjar section, Kutch), the Permo-Triassic
(Guling, Lalung, Ganmachidam and Attargoo sections, Spiti valley) and the Eocene-Oligocene (Tapti River section, Gujarat)
have been identified in the sedimentary records of the Indian subcontinent. These sections have been studied for geochemical
anomalies. The results are discussed in the framework of extra-terrestrial and terrestrial causes proposed to explain the
physical, chemical and mineralogical observations at these boundaries. A critical analysis suggests that although the astronomical
causes, particularly the bolide impacts, can easily explain the geochemical and physical changes, the terrestrial causes (volcanism)
may have played a significant role in creating the biological stress observed in fossil records (mass extinction) at or near
some of these boundaries. 相似文献
577.
巨大撞击对地球演化的系统灾变效应 总被引:1,自引:0,他引:1
综述了巨大地外物体撞击事件对地球产生的一系列剧烈灾变效应,包括撞击事件诱发或产生的各类地质作用变化、古气候波动、古生物灭绝和古地磁倒转等。同时指出,全面深入地研究巨大撞击的灾变效应对认识地球演化和发展具有重要意义。 相似文献
578.
This paper estimates various economic impacts of the annual conferences of the Association of American Geographers (AAG) on the states in which they have been held, from 1983 to 1994. It uses data on the number of registrants at these conferences, the average expenditures and durations of stay of these individuals, and the sectoral distribution of these expenditures. Input-output analysis was employed to estimate the indirect and induced impacts on each state or province. Aggregate expenditures ranged from $890,000 (Denver in 1983) to $2.5 million (Toronto in 1990), while the effect on statewide output ranged from $1.64 million to $4.67 million (same cities). On average, state or provincial output increased by $2.86 million, 90.9 jobs were created, and $717,000 in personal income was generated. These impacts have gradually increased over the time period in question. 相似文献
579.
《The Professional geographer》2013,65(4):430-435
Book Reviewed in this article: Latin America: Case Studies. Richard G. Boehm and Sent Visser Locality and Rurality: Economy and Society in Rural Regions. Tony Bradley And Philip Lowe The City and the Grassroots. Manuel Castells Geopolitics and Conflict in South America. Quarrels among Neighbors. Jack Child Post-Industrial America: A Geographical Perspective. David Clark Coastal Research: UK Perspectives. Malcolm W. Clark A Rural Policy for the EEC? Hugh Clout Peasant Agriculture in Assam: A Structural Analysis. M. M. Das. Environmental Change and Tropical Geomorphology. I. Douglas and T. Spencer Advances in Abandoned Settlement Analysis: Application to Prehistoric Anthrosols in Colombia, South America. Robert C. Eidt Measuring Culture. Jonathan L. Gross and Steve Rayner North America: A Human Geography. Paul Guinness and Michael Bradshaw A Geographical Bibliography for American Libraries. Chauncy D. Harris et al. Geography and the Urban Environment: Progress in Research and Applications, Vol. VI. D. T. Herbert and R. J. Johnston Changes in Global Climate: A Study of the Effect of Radiation and Other Factors During the Present Century. K. Ya. Kondrat'ev. Rural Development and the State: Contradictions and Dilemmas in Developing Countries. David A. M. Lea and D. P. Chaudhri The Martial Metropolis: U.S. Cities in War and Peace. Roger W. Lotchin The Climate of the Earth. Paul E. Lydolph. Weather and Climate. Paul E. Lydolph. Spatial Divisions of Labor: Social Structures and the Geography of Production. Doreen Massey. Panorama of the Soviet Union. N. Mikhailov. Soviet Armenia. K. S. Demirchian. USSR: Geography of the Eleventh Five-Year Plan Period. K. Spidchenko. Planung und Verwirklichung der Wiener Ringstrassenzone (Planning and Materialization of the Ringstrasse-Zone of Vienna). Kurt Mollik, Hermann Reining, Rudolf Wurzer. The American West Transformed: The Impact of the Second World War Gerald D. Nash. An Overview of the Survey of Income and Program Participation. Dawn Nelson, David McMillen, and Daniel Kasprzyk. Phenomenology, Science and Geography: Spatiality and the Human Sciences. John Pickles. Biological Diversification in the Tropics. Ghillean T. Prance Die Wanderviehwirtschaft im gebirgigen Westen der U.S.A. und ihre Auswirkungen im Naturraum. Gisbert Rinschede. Social and Economic Aspects of Radioactive Waste Disposal: Considerations for Institutional Management World-Wide Weather. K. Takahashi Coastal Geomorphology in Australia. B. G. Thom Settlement System in Rural India: A Case Study of the Lower Ganga-Yamuna Doab. Ram Chandra Tiwari. Computer Programming for Geographers. David J. Unwin and John A. Dawson. Late Quaternary Environments of the Soviet Union. A. A. Velichko, ed. H. E. Wright, Jr. and C. W. Barnosky Ethics in Planning. Martin Wachs 相似文献
580.
Mike Hilton Nick Harvey Andrew Hart Kris James Chris Arbuckle 《The Australian geographer》2006,37(3):313-334
Marram grass (Ammophila arenaria) and sea-wheat grass (Thinopyrum junceiforme) have been introduced to Australia and New Zealand. This study examines the morphology of incipient foredunes and established foredunes associated with these species at two sites, Mason Bay in southern New Zealand, and the Younghusband Peninsula in South Australia. Both species invaded the existing foredunes very rapidly. In both cases the antecedent topography comprised relatively sparsely vegetated, irregular foredunes. Invasion resulted in continuous, regular, evenly vegetated foredunes. At Mason Bay a massive foredune has formed since 1958, in conjunction with Ammophila. Thinopyrum has formed an incipient foredune, with a ramp or terrace morphology, along the Younghusband Peninsula, South Australia. In both cases gaps in the former foredune have been closed and the indigenous foredune vegetation has been displaced. Both species may decrease the frequency and severity of blowout development. They are likely to be resilient to aeolian processes of sedimentation compared with dunes formed by indigenous species. Ammophila survives burial, is tolerant of drought and is resistant to erosion associated with storm surge and high waves. Thinopyrum is very tolerant of salinity. These species may adversely affect the long-term development of coastal barriers by inhibiting transgressive dune development. 相似文献