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371.
372.
Insights from experimental economics on local cooperation in a small-scale fishery management system
Shankar Aswani Georgina G. Gurney Sara Mulville Jaime Matera Michael Gurven 《Global Environmental Change》2013,23(6):1402-1409
Cooperation is central to collective management of small-scale fisheries management, including marine protected areas. Thus an understanding of the factors influencing stakeholders’ propensity to cooperate to achieve shared benefits is essential to accomplishing successful collective fisheries management. In this paper we study stakeholders’ cooperative behavioral disposition and elucidate the role of various socio-economic factors in influencing it in the Roviana Lagoon, Western Solomon Islands. We employed a Public Goods Game from experimental economics tailored to mimic the problem of common pool fisheries management to elucidate peoples’ cooperative behavior. Using Ostrom's framework for analyzing social-ecological systems to guide our analysis, we examined how individual-scale variables (e.g., age, education, family size, ethnicity, occupational status, personal norms), in the context of village-scale variables (e.g., village, governance institutions, group coercive action), influence cooperative behavior, as indexed by game contribution. Ostrom's framework provides an effective window for conceptually peeling back the various socio-economic and governance layers which influence cooperation within these communities. The results of our research show that the most important resource user characteristics influencing cooperative behavior were age, occupation and beliefs about giving access to others to fish for commercial gain. Through elucidating the factors affecting stakeholders’ propensity to cooperate to achieve shared benefits, our analysis provides guidance in understanding cooperation in relation to collective management of marine resources. 相似文献
373.
Subhajyoti Das 《Journal of the Geological Society of India》2012,80(2):287-289
374.
Satellite detection of thermal precursors of Yamnotri,Ravar and Dalbandin earthquakes 总被引:2,自引:1,他引:1
Saraf Arun K. Rawat Vineeta Das Josodhir Zia Mohammed Sharma Kanika 《Natural Hazards》2012,61(2):861-872
Prior to the occurrence of an earthquake, the region undergoes intensive physiochemical changes. Such changes trigger degassing
charge generation leading to positive change in the thermal regime and consequently creation of an earthquake preparation
zone. These changes in thermal regime can be detected by the thermal sensors onboard various polar orbiting satellites. Recent
researches have demonstrated that thermal infrared sensors onboard satellites (e.g., NOAA-AVHRR and Terra/Aqua-MODIS) can
detect temporal transient thermal infrared anomalies prior to an earthquake. The paper presents satellite-based thermal observations
associated with Yamnotri (July 22, 2007, India), Ravar (October 14, 2004, Iran) and Dalbandin (January 19, 2011, Pakistan)
earthquakes. In the case of Yamnotri earthquake, the region attained around 5–8°C higher than the normal temperature on July
21, 2007 in the area, just 1 day before the earthquake. Whereas, in the case of Ravar earthquake, the region has shown 5–7°C
higher temperature on October 06, 2004 about 6 days before the occurrence of the main earthquake event. Dalbandin earthquake
showed a maxima on January 17, 2011, just 2 days before the main shock with the raised temperature of around 8–10°C. Another
common observation in all these earthquakes is the disappearance of short-term transient thermal anomaly just before the main
shock. 相似文献
375.
Pseudopotential analysis has been employed to derive a modified Sagdeev potential-like wave equation for studying the sheath
formation in astroplasma problems. Complexity in process urges to derive the new findings numerically by using fourth-order
Runge-Kutta method. Main emphasis has been given to investigate the role of Coriolis force on the formation and changes on
coherent structures of sheath suitably thought for the configuration of astroplasma. Study determines the sheath thickness
and potential variation with the interaction of Coriolis force and thereby finds dynamical behavior of levitated dust grains
into the evaluated sheath region. This leads to find the dust size, and corresponding forces generated on dust grain with
a view to relate theoretical observations to real astrophysical phenomena and could be of interest to explain formation of
dust clouds in spaces. To support the observations, we some thoughtful numeric plasma parameters for the case of Earth’s Moon,
have taken for graphical presentations. Overall observations expect the study could be of interest as an advanced knowledge
in rotating astroplasmas, and expecting many salient features which are yet to be known. 相似文献
376.
A Mukherjee D Shankar V Fernando P Amol S G Aparna R Fernandes G S Michael S T Khalap N P Satelkar Y Agarvadekar M G Gaonkar A P Tari A Kankonkar S Vernekar 《Journal of Earth System Science》2014,123(6):1197-1232
We present data from three acoustic Doppler current profilers (ADCPs) moored off Cuddalore (12°N), Kakinada (16.5°N), and Gopalpur (19°N) on the continental slope of the western Bay of Bengal and one mooring on the slope of the northern bay (89°E, 19°N; referred to as being located at Paradip). The data were collected during May 2009 to March 2013 and the observations show that the seasonal cycle, which includes the annual cycle, the semi-annual cycle, and a peak around 120 days, dominates the observed variability of the East India Coastal Current (EICC). Spectral analysis suggests that the 120-day peak dominates the seasonal variability at Paradip and is strong at Gopalpur and Kakinada. The annual cycle is coherent along the western boundary of the bay, i.e., the east coast of India, but with significant phase differences between moorings. At the semi-annual and 120-day periods, the alongshore coherence is weaker. Intraseasonal variability is weaker than the seasonal cycle, particularly at Cuddalore and Paradip, and it exhibits seasonality: the strongest intraseasonal variation is during spring (February–April). Peaks around 12 and 20–22 days are also seen at Gopalpur, Kakinada, and Cuddalore. A striking feature of the currents is the upward phase propagation, but there are also instances when phase propagates downward. The much lower vertical phase speed in the top ~100 m at Cuddalore leads to a distinct undercurrent at this location; at other locations, the undercurrent, though it exists often, is not as striking. During spring, however, the EICC tends to flow poleward (eastward) at Cuddalore, Kakinada, and Gopalpur (Paradip) over the top ~300 m, which is the maximum depth to which observations were made. The cross-shore component of the EICC is much weaker than the alongshore component at Cuddalore and, except for a few bursts during spring, at Kakinada and Gopalpur. It is only at Paradip, on the slope of the northern boundary, that significant cross-shore flows are seen during spring and the summer monsoon (June–August) and these flows are seen to be associated with eddy-like circulations in the altimeter data. We use the ADCP data to validate popular current data products like OSCAR (Ocean Surface Currents Analyses Real-time), ECCO2 (Estimating the Circulation and Climate of the Ocean, Phase II), and GODAS (Global Ocean Data Assimilation System). The OSCAR currents at Paradip match the observed currents well, but the correlation is much weaker at the other three locations. Both ECCO2 and GODAS fair poorly, particularly the latter because its variability in this boundary-current regime is extremely weak. Though it performs badly at Paradip, ECCO2 does capture the observed variability on occasions at the other locations. 相似文献
377.
Mohammed Zia Kanika Sharma Arun Kumar Saraf Josodhir Das Suman Baral Mrinmoy Das 《Natural Hazards》2014,71(3):1379-1388
The central Kutch region of Gujarat, India, experienced a M7.7 earthquake on January 26, 2001, causing large-scale ground deformations including a huge loss of lives and infrastructure. The rupture of a hidden reverse fault was the reason for this intense tectonic activity. The post-seismic ground deformations, attributed to the relaxation phase of a stressed crustal layer, have been analyzed using a pair of Advanced Land Observation Satellite-Phased Array type L-band Synthetic Aperture Radar interferometric synthetic aperture radar (InSAR) images. The InSAR images were obtained in 2007 and 2010, covering an area around Bhuj. It falls on the Kutch Mainland Fault and Katrol Bhuj Fault. Using the ADORE-DORIS software, interferometric imagery has successfully been generated, covering the study area. This allowed making interesting geological inferences. Three different regions in the study area elicited countable visible colored fringes, indicating different amounts of positive and negative ground deformations (surface motion with respect to the satellite). They occurred within the InSAR data acquisition dates. The region around Bhuj and to the north and east of Bhuj showed top surface deformations of about 35, 35, and 24 cm, respectively. The synoptic view of the interferometric image of the study area suggests two crustal fault lines running to the north and south of Bhuj city. The Institute of Seismological Research, geophysical and Global Positioning System data, indicates that huge seismic events occurred during the year 2007–2010 and supports the observational inference of clustering of interferometric fringes to the E and NE of the study area. 相似文献
378.
A. Vignesh A. S. Siddarth O. S. Gokul B. R. Babu 《International Journal of Environmental Science and Technology》2014,11(6):1669-1678
The present contribution reports a moving iron (Fe), zinc (Zn)–doped tin oxide/titanium (SnO2/Ti) anode-based system designed and operated for the electro-oxidation of methyl orange dye effluent. Electrochemical oxidation of the dye was carried out at a current density of 1.8 A/dm2 for 120 min. Similar experiments were repeated with pure SnO2-based static and moving anode-based systems and the Fe, Zn-doped SnO2 static anode-based electro-oxidation system. Post oxidation, the surface of the electrodes was critically examined by scanning electron microscopy. Dye samples were analysed at regular intervals during the electro-oxidation process by chemical oxygen demand and colour removal measurements and characterized by UV–Vis spectroscopy and Fourier transform infrared spectroscopy at the end of the oxidation process. The obtained results elucidate the superiority of Fe, Zn-doped SnO2/Ti moving anode-based system for methyl orange dye effluent electro-oxidation. The moving anode prevents passive layer formation and decreases polarization resistance. Doping of Fe and Zn provides the anode-enhanced mechanical strength and electrocatalytic activity. The combined effects of axial anode movement and doping are responsible for improved performance of the moving anode system reported in this contribution. 相似文献
379.
H. Achyuthan O. Flora M. Braida Navin Shankar B. Stenni 《Journal of the Geological Society of India》2010,75(6):791-798
In this paper we discuss the limitation of radiocarbon dates on the pedogenic calcic nodules formed in situ within the vertisols in the upland region of Coimbatore, Tamil Nadu. The radiocarbon ages were obtained using low-level scintillation
counters and the dates range from ∼24 to 31 14C kyrs BP. The ages correlate with the marine isotope stage of Late MIS3. However, since the calcic nodules are pedogenised
and formed in an open system, the 14C ages should only be considered as estimates and not absolute ages because of the possibility of open-system behaviour with
respect to carbon. Thus, we express caution in the interpretation of these and other radiocarbon ages obtained on pedogenic
carbonate nodules. Multiple sub-mm size subsamples could provide more reliable age estimates. 相似文献
380.