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11.
The Palaeoproterozoic Magondi Supergroup lies unconformably on the Archaean granitoid-greenstone terrain of the Zimbabwe Craton and experienced deformation and metamorphism at 2.06–1.96 Ga to form the Magondi Mobile Belt. The Magondi Supergroup comprises three lithostratigraphic units. Volcano-sedimentary rift deposits (Deweras Group) are unconformably overlain by passive margin, back-arc, and foreland basin sedimentary successions, including shallow-marine sedimentary rocks (Lomagundi Group) in the east, and deeper-water shelf to continental slope deposits in the west (Piriwiri Group). Based on the upward-coarsening trend and presence of volcanic rocks at the top of the Piriwiri and Lomagundi groups, the Piriwiri Group is considered to be a distal, deeper-water time-equivalent of the Lomagundi Group. The Magondi Supergroup experienced low-grade metamorphism in the southeastern zone, but the grade increases to upper greenschist and amphibolite facies grade to the north along strike and, more dramatically, across strike to the west, reaching upper amphibolite to granulite facies in the Piriwiri Group.  相似文献   
12.
Although Himalayan glaciers are of particular interest in terms of future water supplies, regional climate changes, and sea-level rises, little is known about them due to lack of reliable and consistent data. There is a need for monitoring these glaciers to bridge this knowledge gap and to provide field measurements necessary to calibrate and validate the results from different remote sensing operations. Therefore, glaciological observations have been carried out by the Cryosphere Monitoring Project(CMP) since September 2011 on Rikha Samba Glacier in Hidden valley, Mustang district in western Nepal in order to study its annual mass balance. This paper presents the first results of that study. There are 10 glaciers in Hidden Valley, named G1, G2, G3, up to G10. Of these, G5 is the Rikha Samba Glacier, which has the largest area(5.37 km2) in this valley and the highest and lowest altitudes(6,476 and 5,392 m a.s.l., respectively). The glacier mass balance discussed in this paper was calculated using the glaciological method and the equilibrium line altitude(ELA). The glacier showed a negative annual point mass balance along the longitudinal profile of its lower part from September 10, 2011 to October 3, 2012. Stake measurements from October 4, 2012 to September 30, 2013 indicated a negative areal average of annual mass balance-0.088±0.019 m w.e. for the whole glacier. Based on these observations, the ELA of the Rikha Samba Glacier is estimated at 5,800 m a.s.l. in 2013. This negative balance may be due to rising air temperatures in the region, which have been incrementally rising since 1980 accompanied by little or no significant increase in precipitation in that period. The negative mass balance confirms the general shrinking trend of the glacier.  相似文献   
13.
While it has been recognized that actions reducing greenhouse gas (GHG) emissions can have significant positive and negative impacts on human health through reductions in ambient fine particulate matter (PM2.5) concentrations, these impacts are rarely taken into account when analyzing specific policies. This study presents a new framework for estimating the change in health outcomes resulting from implementation of specific carbon dioxide (CO2) reduction activities, allowing comparison of different sectors and options for climate mitigation activities. Our estimates suggest that in the year 2020, the reductions in adverse health outcomes from lessened exposure to PM2.5 would yield economic benefits in the range of $6 to $30 billion (in 2008 USD), depending on the specific activity. This equates to between $40 and $198 per metric ton of CO2 in health benefits. Specific climate interventions will vary in the health co-benefits they provide as well as in potential harms that may result from their implementation. Rigorous assessment of these health impacts is essential for guiding policy decisions as efforts to reduce GHG emissions increase in scope and intensity.  相似文献   
14.
The present study aimed at characterizing the heavy metal resistance and assessing the resistance pattern to multiple heavy metals (300 mmol L?1) by Palk Bay sediment bacteria. From 46 isolates, 24 isolates showed resistance to more than eight heavy metals. Among the 24 isolates S8-06 (Bacillus arsenicus), S8-10 (Bacillus pumilus), S8-14 (B. arsenicus), S6-01 (Bacillus indicus), S6-04 (Bacillus clausii), SS-06 (Planococcus maritimus) and SS-08 (Staphylococcus pasteuri) exhibited high resistance against arsenic, mercury, cobalt, cadmium, lead and selenium. Plasmid curing confirmed that the heavy metal resistance in S8-10 is chromosomal borne. Upon treatment with the heavy metals, the strain S8-10 showed many morphological and physiological changes as shown by SEM, FTIR and AAS analysis. S8-10 removed 47% of cadmium and 96% of lead from the growth medium. The study suggests that sediment bacteria can be biological indicators of heavy metal contamination.  相似文献   
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16.
Sharad Chari 《Geoforum》2007,38(4):599-601
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17.
As developing countries around the world formulate policies to address climate change, concerns remain as to whether the voices of those most exposed to climate risk are represented in those policies. Developing countries face significant challenges for contextualizing global-scale scientific research into national political dynamics and downscaling global frameworks to sub-national levels, where the most affected are presumed to live. This article critiques the ways in which the politics of representation and climate science are framed and pursued in the process of climate policy development, and contributes to an understanding of the relative effectiveness of globally framed, generic policy mechanisms in vulnerable and politically volatile contexts. Based on this analysis, it also outlines opportunities for the possibility of improving climate policy processes to contest technocratic framing and generic international adaptation solutions.

Policy relevance

Nepal's position as one of the countries most at risk from climate change in the Himalayas has spurred significant international support to craft climate policy responses over the past few years. Focusing on the National Adaptation Programme of Action (NAPA) and the Climate Change Policy, this article examines the extent to which internationally and scientifically framed climate policy in Nepal recognizes the unfolding political mobilizations around the demand for a representative state and equitable adaptation to climate risks. This is particularly important in Nepal, where political unrest in the post-conflict transition after the end of the civil war in 2006 has focused around struggles over representation for those historically on the political margins. Arguing that vulnerability to climate risk is produced in conjunction with social and political conditions, and that not everyone in the same locality is equally vulnerable, we demonstrate the multi-faceted nature of the politics of representation for climate policy making in Nepal. However, so far, this policy making has primarily been shaped through a technocratic framing that avoids political contestations and downplays the demand for inclusive and deliberative processes. Based on this analysis, we identify the need for a flexible, contextually grounded, and multi-scalar approach to political representation while also emphasizing the need for downscaling climate science that can inform policy development and implementation to achieve fair and effective adaptation to climate change.  相似文献   

18.
Water balance of a basin involves estimation of input precipitation, runoff, infiltration and evapotranspiration (ET). Although ET may have large variations over a big basin, it is commonly estimated using a few point measurements and this makes the estimation error prone. Satellite based remote sensing data provides few parameters for estimation of energy fluxes, at the land surface and atmosphere interaction in a distributed manner using the meteorological parameters. These parameters through surface energy balance equation have been used for the estimation of ET in this study. Various spatially distributed variables required for ET estimation; viz. NDVI, surface albedo, surface temperature etc. have been derived using remote sensing and ancillary data for Tapi basin located in western India. Beside this field data such as rainfall, air temperature, relative humidity, sunshine hours etc. have been used. For computation of runoff, Soil Conservation Services (SCS) approach has been considered. Tapi basin up to Ukai dam has been selected as the study area. Satellite data from National Oceanic and Atmospheric Administration (NOAA), Polar Orbiting Environmental Satellite, which carries the Advanced Very High Resolution Radiometer (AVHRR), have been used for preparation of various maps required for runoff and ET analysis. The results of runoff and ET have been compared with observed data for 2 years, 2002–2003 and the results have been found in good agreement with observed data.  相似文献   
19.
Data of Wide Field Sensor (WiFS) to go onboard Indian Remote Sensing Satellite, IRS-1C, in December 1995, is simulated mainly from IRS IB LISS I data of Bhadra command area, Karnataka (India) during 1993–94 summer season, to evaluate its capability in concurrent monitoring of irrigated crops at disaggregated level Crop area, crop-growth profiles of homogeneous crops like paddy, as obtained from both simulated WiFS data and LISS I data are very close for almost all the distributary commands of Bhadra project Though non-paddy-crop groups could also be classified satisfactorily, the Workability with small-extent-individual crops like groundnut, garden and sugarcane is found to be less due to coarse resolution of WiFS data and hence the individual crops could not be separated out. This study proves the potential of WiFS in concurrent monitoring of fairly-large-extent irrigated crops at distributary level. The basic feasibility of WiFS had been established in an earlier work at broad level and this study demonstrates the feasibility of information extraction at distributary command level from WiFS data.  相似文献   
20.
In this article we study the effect of a non-ideal gas parameter on the piston (contact) surface when a strong shock moves into a non-uniform medium. The solution corresponding to the ideal gas can be obtained as a particular case of the analysis.  相似文献   
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