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121.
Acid mine drainage (AMD) is one of the most significant environmental challenges facing the mining industry worldwide. For this reason, many methods for AMD treatment are developed, being wetlands a good option for metal elements removal from these mining effluents. The efficiency of Peruvian native plants such as Schoenoplectus californicus (S. californicus) to remove metal elements in effluents through artificial wetlands is studied. Batch removal tests are carried out with different effluents containing copper, zinc, lead, and iron. For iron-metal binary effluents, copper, zinc, and lead are removed by 82%, 75%, and 88%; while in the effluent containing all metals, the removal rate is 90% and 92% for copper and lead, respectively. According to the preliminary results, it is concluded that iron interferes more in the removal of zinc and lead than in copper from binary effluents. The use of S. californicus turns out to be an efficient, attractive, and economical alternative for the treatment of effluents contaminated with copper, zinc, lead, and iron. 相似文献
122.
M. C. Ramadevi S. Seetha Dipankar Bhattacharya B. T. Ravishankar N. Sitaramamurthy G. Meena M. Ramakrishna Sharma Ravi Kulkarni V. Chandra Babu Kumar Brajpal Singh Anand Jain Reena Yadav S. Vaishali B. N. Ashoka Anil Agarwal K. Balaji G. Nagesh Manoj Kumar Dhruti Ranjan Gaan Prashanth Kulshresta Pankaj Agarwal Mathew Sebastian A. Rajarajan D. Radhika Anuj Nandi V. Girish Vivek Kumar Agarwal Ankur Kushwaha Nirmal Kumar Iyer 《Experimental Astronomy》2017,44(1):11-23
Scanning Sky Monitor (SSM) onboard AstroSat is an Xray sky monitor in the soft X-ray band designed with a large field of view to detect and locate transient X-ray sources and alert the astronomical community about interesting phenomena in the X-ray sky. SSM comprises position sensitive proportional counters with 1D coded mask for imaging. There are three detector units mounted on a platform capable of rotation which helps covering about 50% of the sky in one full rotation. This paper discusses the elaborate details of the instrument and few immediate results from the instrument after launch. 相似文献
123.
Global assessment of the European Union fishing fleet: An update 总被引:1,自引:0,他引:1
This paper provides a global analysis of recent trends in the EU fishing fleet. Analysis of the capital productivity, labour rates, and economic benefits of the fleet revealed that considerable replacement of fishermen by better technology and well-equipped vessels occurred between 1990 and 2006. The analysis confirms that the Common Fisheries Policy (CFP) has been ineffective in reducing fishing capacity. In addition, the changes in capacity that occurred in this time interval differed among the different sectors of the fleet. Some members of the high sea fishing fleet increased their capacity (range 11–57%), and the deep-sea sector, which has greater tonnage and fishing power, increased its fishing capacity by 34–44%. These results confirm the ineffectiveness of the CFP in reducing overcapacity and illustrate the continuing threat of overcapacity to the long-term sustainability of fishery resources. 相似文献
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Perelet Alexei O. Gultepe Ismail Hoch Sebastian W. Pardyjak Eric R. 《Boundary-Layer Meteorology》2021,181(2-3):295-315
Boundary-Layer Meteorology - We investigate the path-averaged visibility and discrimination of fog and rain events using a two-wavelength (near-infrared and microwave) scintillometer system. These... 相似文献
126.
A clear and present danger: Ladakh's increasing vulnerability to flash floods and debris flows
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Alan D. Ziegler Sebastian I. Cantarero Robert J. Wasson Pradeep Srivastava Sonam Spalzin Winston T. L. Chow Jamie Gillen 《水文研究》2016,30(22):4214-4223
This preliminary investigation of the recent spate of deadly flash floods and debris flows in Ladakh (India) over the last decade identifies uncontrolled development in hazardous locations as an important factor contributing to loss of life and property damage in this high mountain desert. The sediments exposed in the channel banks and on the alluvial fans of several mountain streams in the area indicate a long history of flash floods and debris flows resulting from intense storms, which appear to have increased in frequency within the last decade. The signposts of these recurrent hazards are being ignored as a growing economy, which is boosted by a well‐established tourism industry, is now driving development onto lands that are susceptible to floods and debris flow hazards. In this science briefing we argue that the increasing vulnerability in Ladakh should be addressed with sound disaster governance strategies that are proactive, rather than reactionary. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Jacob Geersen David Völker Jan H. Behrmann Dirk Kläschen Wilhelm Weinrebe Sebastian Krastel Christian Reichert 《地学学报》2013,25(6):472-477
Determining factors that limit coseismic rupture is important to evaluate the hazard of powerful subduction zone earthquakes such as the 2011 Tohoku‐Oki event (Mw = 9.0). In 1960 (Mw = 9.5) and 2010 (Mw = 8.8), Chile was hit by such powerful earthquakes, the boundary of which was the site of a giant submarine slope failure with chaotic debris subducted to seismogenic zone depth. Here, a continuous décollement is absent, whereas away from the slope failure, a continuous décollement is seismically imaged. We infer that underthrusting of inhomogeneous slide deposits prevents the development of a décollement, and thus the formation of a thin continuous slip zone necessary for earthquake rupture propagation. Thus, coseismic rupture during the 1960 and 2010 earthquakes seems to be limited by underthrusted upper plate mass‐wasting deposits. More generally, our results suggest that upper plate dynamics and resulting surface processes can play a key role for determining rupture size of subduction zone earthquakes. 相似文献
129.
Sebastian Vicuña Jorge Gironás Francisco Javier Meza María Luisa Cruzat Mark Jelinek Eduardo Bustos 《水文科学杂志》2013,58(8):1598-1619
AbstractMotivated by recent extreme flow events in the Mataquito River located in the Mediterranean region of Chile, we performed a detailed trend analysis of critical hydroclimatic variables based on observed daily flow, precipitation and temperature within the basin. For the period 1976–2008, positive trends in temperature were observed, especially during spring and summer months. At the same time, we found negative trends in the frequency and intensity of precipitation, especially during spring months. We observed an increasing difference between average streamflow in the rainy season as compared to the snowmelt season. Part of this trend is caused by larger flows during autumn months, although no positive precipitation trends are observed for these months. Finally, significant reductions in minimum flow during spring/summer and a disproportionate concentration of high-flow events occurring in the last 10 years were also identified. These high-flow events tend to happen during autumn months, and are associated with high precipitation and high minimum temperatures. Based on a simple assessment of changes in irrigated agriculture and land use, we concluded that other non-climatic factors seem not to be as relevant to the detected flow trends. All these results are in accord with future climate change scenarios that show an increase in temperature, a reduction in average precipitation and a reduction in snow accumulation. Such future scenarios could seriously hamper the development of economic activities in this basin, exemplifying also a fate that may be shared by other similar basins in Chile and in other regions of the world.Editor Z.W. KundzewiczCitation Vicuña, S., Gironás, J., Meza, F.J., Cruzat, M.L., Jelinek, M., Bustos, E., Poblete, D., and Bambach, N., 2013. Exploring possible connections between hydrological extreme events and climate change in central south Chile. Hydrological Sciences Journal, 58 (8), 1598–1619. 相似文献
130.
Markus Fuchs Sebastian Kreutzer Denis‐Didier Rousseau Pierre Antoine Christine Hatté France Lagroix Olivier Moine Caroline Gauthier Jiri Svoboda Lenka Lisá 《Boreas: An International Journal of Quaternary Research》2013,42(3):664-677
The Dolní Věstonice loess section in the Czech Republic is well known for its high‐resolution loess–palaeosol sequence of the last interglacial–glacial climatic cycle (Upper Pleistocene). The loess section is situated in a climatic transition zone between oceanic and continental climates and is therefore of great value in reconstructing past regional climate conditions and their interaction with climate systems, in particular that of the North Atlantic. Based on a combination of optically stimulated luminescence (OSL) ages, stratigraphic field observations and magnetic susceptibility measurements, a chrono‐climatic interpretation of the Dolní Věstonice loess section is presented. To establish a reliable Upper Pleistocene chronology, a quartz OSL approach was applied for equivalent dose (De) determination. Monomineralic quartz extracts of three distinct grain sizes, fine (4–11 μm), middle (38–63 μm) and coarse (90–200 μm), were used and compared. Within error limits, the calculated OSL ages are the same for the different grain sizes, and the OSL ages are in stratigraphic order. The established OSL chronology is in agreement with a Weichselian litho‐ and pedostratigraphy. The Dolní Věstonice loess section is characterized by four pedosedimentary subsequences. At the base of the profile, subsequence I is characterized by a distinct Early Glacial soil complex, OSL‐dated to c. 110 to 70 ka, representing one of the most complete records of environmental change in the European loess belt. Subsequence II is allocated to the Lower Pleniglacial and is characterized by laminated sandy loess. Middle Pleniglacial subsequence III is represented by a brown soil complex, and is followed by the uppermost subsequence IV, characterized by a thick body of laminated sandy loess, indicating strong wind activity and a high sedimentation rate of more than ~1 mm a?1 during the Upper Pleniglacial. According to the OSL chronology, as well as to the sedimentological and palaeopedological investigations, it is likely that the sequence at Dolní Věstonice has recorded most of the climatic events expressed in the NGRIP δ18O reference record between 110 and 70 ka. 相似文献