Remote Sensing and Geographic Information System has become one of the leading tools in the field of hydrogeological science,
which helps in assessing, monitoring and conserving groundwater resources. It allows manipulation and analysis of individual
layer of spatial data. It is used for analysing and modelling the interrelationship between the layers. This paper mainly
deals with the integrated approach of Remote Sensing and geographical information system (GIS) to delineate groundwater potential
zones in hard rock terrain. The remotely sensed data at the scale of 1:50,000 and topographical information from available
maps, have been used for the preparation of ground water prospective map by integrating geology, geomorphology, slope, drainage-density
and lineaments map of the study area. Further, the data on yield of aquifer, as observed from existing bore wells in the area,
has been used to validate the groundwater potential map. The final result depicts the favourable prospective zones in the
study area and can be helpful in better planning and management of groundwater resources especially in hard rock terrains. 相似文献
A Recent Contamination Trend: Polycylic Aromatic Hydrocarbons (PAHs) in Aquatic and Terrestrial Sediments Concentrations of polycylic aromatic hydrocarbons (PAHs) measured in aquatic sediments of small, medium‐sized or very large inland lakes, of estuaries as well as in terrestrial sediments from Germany, the UK, Finland, and the USA were plotted in 10 trend curves over the period from 1800 to 1990. The segments of the bore cores were dated for their deposition age. For comparability of the results, the trend is preferentially shown by the guide parameter fluoranthene. Until the 19th century, a constant background value of CFluo = 10…50 μg/kg was observed in all regions. Then a steep increase in concentration followed, reaching in the aquatic sediments a maximum in the period 1940 to 1965, while the individual fluoranthene values ranged widely from 90 to 2400 μg/kg. In several regions, a more or less distinct decrease superseded this maximum, although this development did not appear in terrestrial sediments, in one estuary, and in remote forest lakes in Finland. The trend curves reflect the atmospheric deposition of PAHs in airborne dust and in some cases the import through runoff via rivers. Thus, the sediment profiles depict the development of air pollution by pyrogenic contaminants over more than a century. Sediment profiles from rivers can be used only with a high degree of reservation, because of the irregularity and low representativity of the sedimentation. 相似文献
Ar–Ar age measurements are reported for selected eclogitic clinopyroxene and garnet inclusions in Orapa diamonds and clinopyroxene inclusions in Venetia diamonds. Laser drilling of encapsulated clinopyroxene inclusions within Venetia diamonds released a maximum of 3% of the total 40Ar, indicating little diffusive transfer and storage of radiogenic 40Ar at the diamond–inclusion boundary. Apparent ages obtained during stepped heating of three diamonds are consistent with diamond crystallisation occurring just prior to the kimberlite eruption 520 Ma ago. Stepped heating of three clinopyroxene-bearing Orapa diamonds gave ages of 906–1032 Ma, significantly above the eruption age, but consistent with previously determined isotopic ages. A few higher apparent ages hint at the presence an older generation of Orapa diamonds that formed >2500 Ma ago. Orapa garnets also contain measurable K contents, and record a range of ages between 1000 and 2500 Ma. The old apparent ages and lack of significant interface 40Ar released by the laser probe, suggests that pre-eruption radiogenic 40Ar and mantle-derived 40Ar components are trapped in microinclusions within the pyroxene and garnet inclusions. 相似文献
A granitic rock avalanche, one of the largest Quaternary landslides in Arizona outside the Grand Canyon with a volume of approximately 5.25 M m3 and a width a little under 0.5 km, ran 1 km from the eastern McDowell Mountains. With lateral levees and pressure ridges, the rock avalanche deposit displays many features found on classic sturzstroms. Failure occurred along a major joint plane paralleling the slope with a dip of 44°, when a major base level lowering event in the Salt River system would have undermined the base of the failed slope, and probably during a period of more moisture than normally available in the present-day arid climate. Failure at the subsurface weathering front highlights the importance of the dramatic permeability change between grussified regolith and relatively fresh bedrock. Rock varnish microlaminations (VMLs) dating, in concert with other geomorphic evidence, suggests that the rock avalanche deposit is slightly older than 500 ka. The rock vanish results also have important implications for sampling strategies designed to use cosmogenic nuclide to date Quaternary landslide deposits. Discovery of a large landslide in close proximity to the extending urban fringe of metropolitan Phoenix argues for a more careful analysis of landslide hazards in the region, especially where rapid development excavates bedrock at the base of steep mountain slopes and where the subsurface weathering front is near the surface. 相似文献
Agriculture is responsible for the bulk of Ireland’s greenhouse gas (GHG) emissions. However, the potential to mitigate some of these emissions through the adoption of more efficient farm management practices may be hampered by farmers’ awareness and attitude towards climate change and agriculture’s role in contributing to GHG emissions. This paper presents results from a survey of 746 Irish farmers in 2014, with a view to understanding farmers’ awareness of, and attitudes to, climate change and GHG emissions. Survey results show that there was a general uncertainty towards a number of questions related to agricultural GHG emissions, e.g. if tilling of land causes GHG emissions, and that farmers were reluctant to take action to reduce GHG emissions on their farm. To further explore farmers’ attitudes towards climate change, a multinomial logit model was used to examine the socio-economic factors that affect farmers’ willingness to adopt an advisory tool that would show the potential reduction in GHG emissions from the adoption of new technologies. Results show that farmers’ awareness of human-induced global climate change was positively related to the tool’s adoption.
Key policy insights
Irish farmers are generally not sufficiently aware of the impact of their activities on climate change.
A quarter of farmers believed that climate change will only impact on their business in the long-term; such an attitude may lead to a reluctance amongst these farmers to adopt management practices that reduce GHG emissions.
Awareness of climate change affects positively the adoption of new tools to reduce GHG emissions on farmers’ farms.
IT literacy affects willingness to adopt new tools to address GHG emissions.
Reception of agri-environmental advice can have a positive influence on farmers’ willingness to adopt new GHG emission abatement tools.
Farmers in receipt of environmental subsidies are more likely to adopt new abatement tools, either because they are more environmentally conscious or because the subsidy raised their environmentally consciousness.
Willingness to adopt differs between different farm enterprises; operating dairy enterprise increases the willingness to adopt new advisory mitigation tools.