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701.
Stewart Barr  Andrew Gilg 《Geoforum》2006,37(6):906-920
This paper examines the nature of environmental action in and around the home. Given the rise of local sustainable development and the emphasis placed on individual actions for sustainability, the paper examines the role of citizens in adopting sustainable lifestyles, incorporating a range of behavioural responses from energy saving and water conservation, to waste recycling and green consumption. Focussing on the debate in geography concerning the engagement of the public in environmental action, the paper argues that despite the assertions of those who advocate a deliberative approach to engagement (see [Owens, S., 2000. Engaging the public: information and deliberation in environmental policy. Environment and Planning A 32, 1141–1148]), an approach based on a social–psychological understanding of behaviour can have significant benefits. Such an approach is being developed by geographers in a range of settings and in this paper these developments are situated within the context of existing research that has identified environmental ‘activists’ in terms of their values, attitudes and demographic composition. The paper aims to examine environmental behaviour in relation to two key issues: (1) the way in which environmental action is framed in everyday practices (such as consumption behaviour) and (2) how these practices are reflected amongst different segments of the population to form lifestyle groups. The paper provides new insights for examining sustainable lifestyles that further our appreciation of how actions to help the environment are lived in everyday practices and framed by different lifestyle groups. Accordingly, the paper offers both academics and policy makers new insights into the potential use of focussing on lifestyle groups as a means for changing behaviour.  相似文献   
702.
Atomic weapons testing at the Nevada Test Site has introduced many tracers for quantifying subsurface hydrologic transport processes in arid climates. In 1975, groundwater adjacent to the Cambric test, conducted beneath Frenchman Flat 10 years earlier, was pumped steadily for 16 years to elicit information on the migration of residual radioactivity through the saturated zone. Radionuclides in the pumping well effluent, including tritium, 14C, 36Cl, and 85Kr, were extensively monitored prior to its discharge in an unlined ditch, where approximately a third of the flow infiltrated over a distance of 1 km. Radionuclide infiltration through a 220-m thick vadose zone created a second, and rather unique long-term field experiment. Effluent data have been utilized in conjunction with geologic data, new radionuclide measurements, isotopic age-dating estimates, and vadose zone flow and transport models to better understand the movement of radionuclides between the ditch, the water table and a nearby groundwater monitoring well. Detection of tritium in the monitoring well occurred approximately 16 years after its initial discharge into the ditch. Modeling and tritium age dating have suggested 3–5 years of this 16-year transit time occurred solely in the vadose zone. They also suggest considerable recirculation of the pumping well discharge back into the original pumping well. Notably, there have been no observations of 14C or 85Kr in the monitoring well, suggesting their preferential retention or volatilization during transit to the water table.  相似文献   
703.
Calculation of lava effusion rates from Landsat TM data   总被引:1,自引:0,他引:1  
 We present a thermal model to calculate the total thermal flux for lava flowing in tubes, on the surface, or under shallow water. Once defined, we use the total thermal flux to estimate effusion rates for active flows at Kilauea, Hawaii, on two dates. Input parameters were derived from Landsat Thematic Mapper (TM), field and laboratory measurements. Using these parameters we obtain effusion rates of 1.76±0.57 and 0.78±0.27 m3 s–1 on 23 July and 11 October 1991, respectively. These rates are corroborated by field measurements of 1.36±0.14 and 0.89±0.09 m3 s–1 for the same dates (Kauahikaua et al. 1996). Using weather satellite (AVHRR) data of lower spatial resolution, we obtain similar effusion rates for an additional 26 dates between the two TM-derived measurements. We assume that, although total effusion rates at the source declined over the period, the shut down of the ocean entry meant that effusion rates for the surface flows alone remained stable. Such synergetic use of remotely sensed data provides measurements that can (a) contribute to monitoring flow-field evolution, and (b) provide reliable numerical data for input into rheological and thermal models. We look forward to being able to produce estimates for effusion rates using data from high-spatial-resolution sensors in the earth observing system (EOS) era, such as Landsat 7, the hyperspectral imager, the advanced spaceborne thermal emission spectrometer, and the advanced land imager. Received: 25 July 1997 / Accepted: 26 February 1998  相似文献   
704.
705.
I give a status report and outlook concerning the use of the cosmic microwave background anisotropies to constrain the inflationary cosmology, and stress its crucial role as an underlying paradigm for the estimation of cosmological parameters. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
706.
We analyse the window functions for the spherical harmonic mode estimators of all-sky, volume-limited surveys, considering evolutionary effects along the past light-cone which include the deviation of the distance scale from a linear relationship with redshift, linear peculiar velocity corrections, and linear evolution of the density perturbations. The spherical harmonic basis functions are considered, because they correspond most closely to the symmetries of typical survey geometries and of the light-cone effects we consider. Our results show substantial broadening of the windows over that expected by ignoring light-cone effects, indicating the difficulty of measuring the power spectrum independently from cosmology. We suggest that because of light-cone effects, deep redshift surveys should be analysed either in conjunction with CMBR data which determines the cosmological parameters, or by using a Bayesian likelihood scheme in which varying cosmological parameters and a simple parametrization of the primordial power spectrum are assumed as the priors, so that observed data can be mapped from redshift to real space. The derived power spectrum can then be compared with underlying models of fluctuation generation and growth in structure formation to evaluate both these models and the cosmological priors.  相似文献   
707.
Potential seasonal variation in the U-series radioisotopic signatures of lake and input waters was investigated in Hawes Water, north-west England, and the sedimentary record was examined to establish whether any observed seasonality is preserved in the sediment U and Th radioisotopic activity ratios. U-series disequilibrium in the waters is indicative of both surface and shallow sub-surface origins for the dissolved U, and that this supply is influenced by changes in the prevailing hydrological regime. However, the lake is buffered from this seasonality in that the 234U/238U activity ratio remains constant during the year, and the U content undergoes only a marginal decrease during summer. The change in the mechanism of lake sedimentation from allochthonous organic input during winter to autochthonous carbonate formation during summer has a more significant influence on the U-series radioisotopic characteristics of sedimentary record in that the proportion of organic and carbonate material both exhibit a strong control on the234U/238U activity ratio and U content. In addition, significant proportions of sediment U and Th are associated with ferromanganese oxyhydroxides. Given this seasonality, it is of some significance that the 234U/238U activity ratios of the bottom sediments preserve a reasonable record of lake U-series disequilibrium and are, therefore, potential indicators of long-term changes in catchment hydrology.  相似文献   
708.
This study summarizes the results of micropaleontological, sedimentological, and isotope geochemical analyses of cuttings from five deep wells drilled in the Great Salt Lake (Utah, USA). Spanning the last 5.0 million yrs, our environmental history of the Great Salt Lake distinguishes four intervals based on paleobiological and sedimentological characteristics, using a previously developed tephrochronology for age control. For most of its history, the Great Salt Lake Basin has been occupied by a mixture of marsh, shallow lacustrine and sand flat conditions. In contrast, open lake conditions, typical of the Bonneville cycles and the modern Great Salt Lake apparently have only dominated the basin for the past 0.6-0.8 Ma. The two main structural basins in the study area (the North and South Basins) experienced different lacustrine histories. Large but frequently saline lakes occupied the North Basin after about 0.6 Ma. In the South Basin, ephemeral, saline lacustrine conditions started at 2.1 Ma and developed to full lacustrine conditions at 0.3 Ma. Our paleoenvironmental interpretations are broadly consistent with the aquatic palynological records from the same wells, as well as with the prior core- and outcrop-based lines of evidence. However, the differences in lake history between the North and South Basin have not been previously recognized.  相似文献   
709.
710.
A newly developed kite based atmospheric sounding system is described that can be deployed under a wide range of weather conditions. The Delta Kite system can be flown in wind speeds ranging from 4 to 25 ms-1, while the exceptional lift capabilities of the kite allow several kilograms of payload to be attached to the kite and/or tether. In conjunction with its battery powered winch, the Delta Kite atmospheric sounding system is ideally suited to meteorological studies in remote locations where vehicle access may not be possible.  相似文献   
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