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71.
72.
Rupsha Banerjee Josey Kamanda Cynthia Bantilan Naveen P. Singh 《Natural Hazards》2013,65(3):1443-1464
This paper examines the relationship between local institutions and adaptation to climate variability in four semi-arid villages in India. Based on a qualitative survey, it draws attention to the constraints that farming households face, the role of institutions, and the implications for their capacities to adapt. Using an institutional framework, the study examines the role of local institutions in facilitating community adaptation to perceived climate variability. It was found that at the institutional and community level farmers rely on government schemes that provide social safety nets and the private sector such as moneylenders as sources of adaptation options regarding access to credit. Serious constraints emerged, however, in terms of adaptation to what may be a more challenging future. These constraints were further explored by means of grounded theory. The lack of collective feeling and action has hindered bargaining for better market prices and the development of alternate livelihood options. The need for better financial inclusion and access to more formal systems of finance is necessary to increase the overall adaptive capacity of households. During crisis situations or climatic shocks, the absence of these systems means the sale of household assets and resources especially among small and landless groups of farmers. Overall, rural households perceive that public, civic, and private institutions play a significant role in shielding them against the adverse effects of climate variability. The perceived importance of different institutions is, however, different across different categories of farmers, women, and labourers. 相似文献
73.
B. Siva Soumya M. Sekhar J. Riotte Amlan Banerjee Jean-Jacques Braun 《Environmental Earth Sciences》2013,69(7):2311-2335
Hydrogeological and climatic effect on chemical behavior of groundwater along a climatic gradient is studied along a river basin. ‘Semi-arid’ (500–800 mm of mean annual rainfall), ‘sub-humid’ (800–1,200 mm/year) and ‘humid’ (1,200–1,500 mm/year) are the climatic zones chosen along the granito-gneissic plains of Kabini basin in South India for the present analysis. Data on groundwater chemistry is initially checked for its quality using NICB ratio (<±5 %), EC versus TZ+ (~0.85 correlation), EC versus TDS and EC versus TH analysis. Groundwater in the three climatic zones is ‘hard’ to ‘very hard’ in terms of Ca–Mg hardness. Polluted wells are identified (>40 % of pollution) and eliminated for the characterization. Piper’s diagram with mean concentrations indicates the evolution of CaNaHCO3 (semi-arid) from CaHCO3 (humid zone) along the climatic gradient. Carbonates dominate other anions and strong acids exceeded weak acids in the region. Mule Hole SEW, an experimental watershed in sub-humid zone, is characterized initially using hydrogeochemistry and is observed to be a replica of entire sub-humid zone (with 25 wells). Extension of the studies for the entire basin (120 wells) showed a chemical gradient along the climatic gradient with sub-humid zone bridging semi-arid and humid zones. Ca/Na molar ratio varies by more than 100 times from semi-arid to humid zones. Semi-arid zone is more silicaceous than sub-humid while humid zone is more carbonaceous (Ca/Cl ~14). Along the climatic gradient, groundwater is undersaturated (humid), saturated (sub-humid) and slightly supersaturated (semi-arid) with calcite and dolomite. Concentration–depth profiles are in support of the geological stratification i.e., ~18 m of saprolite and ~25 m of fracture rock with parent gneiss beneath. All the wells are classified into four groups based on groundwater fluctuations and further into ‘deep’ and ‘shallow’ based on the depth to groundwater. Higher the fluctuations, larger is its impact on groundwater chemistry. Actual seasonal patterns are identified using ‘recharge–discharge’ concept based on rainfall intensity instead of traditional monsoon–non-monsoon concept. Non-pumped wells have low Na/Cl and Ca/Cl ratios in recharge period than in discharge period (Dilution). Few other wells, which are subjected to pumping, still exhibit dilution chemistry though water level fluctuations are high due to annual recharge. Other wells which do not receive sufficient rainfall and are constantly pumped showed high concentrations in recharge period rather than in discharge period (Anti-dilution). In summary, recharge–discharge concept demarcates the pumped wells from natural deep wells thus, characterizing the basin. 相似文献
74.
A. Banerjee M. Jha A. K. Mittal N. J. Thomas K. N. Misra 《Marine and Petroleum Geology》2000,17(10):7
Source rock screening reveals five laterally extending potential sources (PS) in the Paleogene. The PSs are SR5 and SR6 in dominantly marine early Eocene to late Paleocene Cambay Shale formation, and SR7, SR8/9, and SR11/12 in dominantly freshwater early Paleocene Olpad formation. Only 3 PSs, SR11/12, SR8/9, and SR7 have attained vitrinite reflectance of 0.75% at 45, 7, and 2 mybp, respectively. Chromatographic and isotope data of oils and PS samples suggest that mainly the Olpad source rocks: SR7 and SR8/9 contributed to the discovered oils. The Cambay Shale source rocks, SR5 and SR6, contrary to the prevalent view, possibly have no significant contribution towards the accumulated oils. 相似文献
75.
76.
Arun K. Saraf Vineeta Rawat Priyanka Banerjee Swapnamita Choudhury Santosh K. Panda Sudipta Dasgupta J. D. Das 《Natural Hazards》2008,47(1):119-135
Stress accumulated in rocks in tectonically active areas may manifest itself as electromagnetic radiation emission and temperature
variation through a process of energy transformation. Land surface temperature (LST) changes before an impending earthquake
can be detected with thermal infrared (TIR) sensors such as NOAA-AVHRR, Terra/Aqua-MODIS, etc. TIR anomalies produced by 10
recent earthquakes in Iran during the period of Jun 2002–Jun 2006 in the tectonically active belt have been studied using
pre- and post-earthquake NOAA-AVHRR datasets. Data analysis revealed a transient TIR rise in LST ranging 2–13°C in and around
epicentral areas. The thermal anomalies started developing about 1–10 days prior to the main event depending upon the magnitude
and focal depth, and disappeared after the main shock. In the case of moderate earthquakes (<6 magnitude) a dual thermal peak
instead of the single rise has been observed. This may lead us to understand that perhaps pre-event sporadic release of energy
from stressed rocks leads to a reduction in magnitude of the main shock. This TIR temperature increment prior to an impending
earthquake can be attributed to degassing from rocks under stress or to p-hole activation in the stressed rock volume and
their further recombination at the rock–air interface. A precise correlation of LST maps of Bam and Zarand with InSAR-generated
deformation maps also provides evidence that the thermal anomaly is a ground-related phenomenon, not an atmospheric one. 相似文献
77.
Growing demand for potable water for various needs has lead to indiscriminate exploitation of groundwater resources, particularly,
in the terrain where surface water resources are negligible. One such area is an island where groundwater is the only source
of fresh water. Groundwater is the prime source of fresh water on most of the atolls in the world. Groundwater on these islands
is in the form of thin fragile floating lens and is often vulnerable to overexploitation, draught, tidal waves, tsunami and
cyclone resulting in seawater ingress. Sustainable development of this meager source of fresh groundwater for a longer time
becomes a more difficult task on small atolls with a large population depending on this vital resource. To develop a sustainable
management scheme and identify the vulnerable part of aquifer, characterization of the aquifer system on islands is imperative.
Groundwater on an atoll is extremely vulnerable to seawater mixing through natural as well as human activities. One such natural
process is the tides of the ocean. The response of sea tide to the water table on the island offers valuable data as well
as cost-effective means to characterize an aquifer system. Such characterization is vital for the management of groundwater
resources on an atoll. The obtained results have compared well with the parameters obtained through a conventional pumping
test. Therefore, the use of tidal response to the water table, which can easily be recorded, provides a rapid and cost-effective
means to characterization of the aquifer system on the island. 相似文献
78.
Junction conditions are studied at the boundary of a higher dimensional spherical distribution containing an outgoing heat flow and radiation flux. Our analysis extends to higher dimension, an important observation of Santos that for a collapsing fluid with radial heat flow the isotropic pressure on the surface of discontinuity does not vanish. Some physically relevant parameters like luminosity, mass function for the bounded distribution and also the time required for horizon formation are also calculated and it is observed that the dimensionality of space-time does not qualitatively alter the analogous results of the standard space time. 相似文献
79.
—Maximum entropy spectral analysis (MESA) has been applied to 24 series of hourly daily data and only one daily mean series for the horizontal (H) and vertical (Z) components of the geomagnetic field for the year 1983 as observed at Narssarssuaq, Greenland (71.2°N, 36.7°E) (gm coordinate). The method has isolated some prominent medium frequency signal components. The maximum peaks for H are at 06 hr (0.174 cycles per day (cpd), 3.2 × 104 db) and 08 hr (0.09 cpd, 3.5 × 104 db). Similarly, the maximum peak in Z is observed at 04 hr (0.114 cpd, 5.7 × 104 db). The spectral results for the daily-mean data indicate periods are greater than two days, with 178.5 days (nearly semiannual) being common to both H and Z. Other harmonics have been found for all the series of H and Z components which are mainly caused by the "Effective Period", i.e., the period produced by the combined effect of the sunspot numbers and the sun’s rotation period. Such frequencies correspond very well with those found in the geomagnetic indices A p ?, C p and AE. This suggests that the disturbance transient variations are caused by viscous interaction of the solar energies emanating from sunspot regions with the outermost magnetospheric boundary which, in turn, influences the magnetosphere-iono sphere coupling and produces the medium intensity long-duration continuous auroral activities (MILD CAAs) over high latitude regions. Thus, the higher latitude geomagnetic activities are nothing but the "effective period driven MILDCAAs" having a recurrence tendency of 27/n, where n is an integer. 相似文献
80.
S. Jacob A. D. Chintagunta R. Banerjee 《International Journal of Environmental Science and Technology》2016,13(10):2363-2374
Potato being the staple vegetable in India is widely cultivated and processed for different value additions. During processing of potato, a huge amount of waste is generated in the form of peel and meat (mash). These wastes constitute a potential feedstock for biogas generation. The present study is focused on mitigation of acidogenesis that occurs during early stages of anaerobic digestion (AD) of potato waste which eventually inhibits the process of methanogenesis. A novel strategy of selective digestion was adopted in which the leachate and solid slurry resulting from the first stage digestion were further subjected to second stage by separating the solid and liquid phases. The obtained results indicated that stepwise digestion enhanced biomethane yield with an increase in methane percent from 46.47 to 60.4 % and reduction in total COD to about 94 %. Another novel strategy adopted in this study was the use of specifically developed microbial consortia for AD of potato wastes instead of conventional inoculum for production of biogas. The obtained yield is at par with the conventional inoculums which suggests that the developed consortia could act as potential substitute. The present study paves the way for sustainable utilization of industrial potato wastes for bioenergy production by overcoming the problems associated with conventional processes. 相似文献