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41.
42.
Margaret Alston Kerri Whittenbury Deb Western Aaron Gosling 《The Australian geographer》2016,47(1):49-64
Concerns for river health in the Murray-Darling Basin (MDB) area and shifting priorities for water use have led to a significant process of water reform over the last decade. The MDB area, also known as the food bowl of Australia, produces much of the country's food and is home to a significant portion of the population. A long-term drought, historical over-allocation of water for irrigation and climate variability have led to mounting concerns about the long-term viability of the rivers. While the reform process has resulted in the Commonwealth government taking control of the rivers from the States, it has also been influenced by changes in governments and consequent shifts in water allocation priorities from a privileging of agriculture to a broader approach encompassing economic, environmental and social concerns. This had led to uncertainty for the people and communities in the Basin and some confusion between the various layers of governance structures. This paper presents the results of exploratory research conducted with key, high-level stakeholders involved in water reform to examine their perceptions of the evolving water policy process. Despite agreement amongst stakeholders that returning water to the environment to ensure river health is critical, our research reveals significant tensions between stakeholders concerning the evolving process, particularly centred on the potential social outcomes and fairness and equity. This suggests the need for more integrated and transparent governance structures, attention to levels of trust between partners and a common vision that incorporates environmental, economic and social goals. 相似文献
43.
The ENE-plunging macroscopic folds, traced by calc gneiss interbanded with marble and sillimanite schist within the Peninsular
Gneiss around Suganapuram in the ‘Palghat gap’ in southern India, represent structures of the second generation (D2). They have folded the axial planes of a set of D1 isoclinal folds on stratification coaxially, so that the mesoscopic D1 folds range from reclined in the hinge zones, through inclined to upright in the limb zones of the D2 folds. Orthogonal relation between stratification and axial planar cleavage, and ‘M’ shaped folds on layering locate the
hinge zones of the D1 folds, whereas folds on axial planar cleavage with ‘M’ shaped folds are the sites of the D2 fold hinges. Extreme variation in the shapes of the isoclinal D1 folds from class 1B through class 1C to nearly class 2 of Ramsay is a consequence of buckling followed by flattening on layers
of widely varying viscosity contrast.
The large ENE-trending structures in this supracrustal belt within the Peninsular Gneiss in the ‘Palghat gap’ could not have
evolved by reorientation of NS-trending structures of the Dharwar tectonic province to the north by movement along the Moyar-Bhavani
shear zone which marks the boundary between the two provinces. This is because the Moyar and Bhavani faults are steep dipping
reverse faults with dominant dip-slip component.
Deceased 相似文献
44.
Chowdhury Saheli Deb Argha Barman Chiranjib Nurujjaman Md. Bora Dipok K. 《Natural Hazards》2022,112(2):1477-1502
Natural Hazards - Activity of 222Rn gas in soil has been recorded continuously at three monitoring centres, namely Ravangla and Diphu in the Eastern Himalayan region and Tantloi in the geothermal... 相似文献
45.
Response of multilayer geosynthetic-reinforced bed resting on soft soil with stone columns 总被引:2,自引:0,他引:2
In the present study, a mechanical model has been developed to study the behavior of multilayer geosynthetic-reinforced granular fill over stone column-reinforced soft soil. The granular fill and geosynthetic reinforcement layers have been idealized by Pasternak shear layer and rough elastic membranes, respectively. The Kelvin–Voight model has been used to represent the time-dependent behavior of saturated soft soil. The stone columns are idealized by stiffer springs and assumed to be linearly elastic. The nonlinear behavior of the soft soil and granular fill is considered. The effect of consolidation of soft soil due to inclusion of the stone columns on settlement response has also been included in the model. Plane strain conditions are considered for the loading and reinforced foundation soil system. An iterative finite difference scheme is applied for obtaining the solution and results are presented in nondimensional form. It has been observed that if the soft soil is improved with stone columns, the multilayer reinforcement system is less effective as compared to single layer reinforcement to reduce the total settlement as there is considerable reduction in the total settlement due to stone column itself. Multilayer reinforcement system is effective for reducing the total settlement when stone columns are not used. However, multilayer reinforcement system is effective to transfer the stress from soil to stone column. The differential settlement is also slightly reduced due to application of multiple geosynthetic layers as compared to the single layer reinforcement system. 相似文献
46.
Prashant?KumarEmail author Sanjib?K.?Deb C.?M.?Kishtawal P.?K.?Pal 《Theoretical and Applied Climatology》2017,128(3-4):575-586
The Weather Research and Forecasting (WRF) model and its three-dimensional variational data assimilation system are used in this study to assimilate the INSAT-3D, a recently launched Indian geostationary meteorological satellite derived from atmospheric motion vectors (AMVs) over the South Asian region during peak Indian summer monsoon month (i.e., July 2014). A total of four experiments were performed daily with and without assimilation of INSAT-3D-derived AMVs and the other AMVs available through Global Telecommunication System (GTS) for the entire month of July 2014. Before assimilating these newly derived INSAT-3D AMVs in the numerical model, a preliminary evaluation of these AMVs is performed with National Centers for Environmental Prediction (NCEP) final model analyses. The preliminary validation results show that root-mean-square vector difference (RMSVD) for INSAT-3D AMVs is ~3.95, 6.66, and 5.65 ms?1 at low, mid, and high levels, respectively, and slightly more RMSVDs are noticed in GTS AMVs (~4.0, 8.01, and 6.43 ms?1 at low, mid, and high levels, respectively). The assimilation of AMVs has improved the WRF model of produced wind speed, temperature, and moisture analyses as well as subsequent model forecasts over the Indian Ocean, Arabian Sea, Australia, and South Africa. Slightly more improvements are noticed in the experiment where only the INSAT-3D AMVs are assimilated compared to the experiment where only GTS AMVs are assimilated. The results also show improvement in rainfall predictions over the Indian region after AMV assimilation. Overall, the assimilation of INSAT-3D AMVs improved the WRF model short-range predictions over the South Asian region as compared to control experiments. 相似文献
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Summary The adjoint technique has been widely used over the last two decades in applications involving the dynamics of the Atmosphere
and Ocean. This present study applies this technique in the assimilation of oceanic parameters such as temperature and net-surface
heat flux, in a variable resolution Ocean General Circulation Model (OGCM). The National Center for Environmental Prediction
(NCEP) 1999 July–August global data (sea-surface temperature and derived surface heat flux) and vertical temperature profiles
collected from ORV Sagar Kanya and INS Sagardhwani during the Bay of Bengal Monsoon Experiment (BOBMEX 1999) are used for
assimilation over the Bay of Bengal. The net-surface heat flux and temperature obtained after assimilation show good agreement
with their respective seasonal patterns over the whole Indian Ocean, though there are some differences in the numerical values
of heat fluxes. The vertical profiles of temperature after assimilation over the Bay of Bengal show strong resemblance with
the corresponding ship observations, emphasizing the importance of the adjoint technique in ocean data assimilation. 相似文献