Source Screening Module for Contaminant Transport Analysis Through Vadose and Saturated Zones

At complex sites there may be many potential sources of contaminants within the vadose zone. Screening‐level analyses are useful to identify which potential source areas should be the focus of detailed investigation and analysis. A source screening module (SSM) has been developed to support preliminary evaluation of the threat posed by vadose zone waste sites on groundwater quality. This tool implements analytical solutions to simulate contaminant transport through the unsaturated and saturated zones to predict time‐varying concentrations at potential groundwater receptors. The SSM integrates several transport processes in a single simulation that is implemented within a user‐friendly, Microsoft Excel? ‐ based interface.     

A GCM-based assessment of the global moisture budget and the role of land-surface moisture reservoirs in processing precipitation

The performance of the Canadian Land Surface Scheme (CLASS) when coupled to the CCCma third generation general circulation model is evaluated in an AMIP II simulation. Our primary aim is to understand how CLASS processes moisture and to compare model estimates of moisture budget components with observations. The modelled mean annual precipitation and runoff, and their latitudinal structures, compare well with observations although some discrepancies remain in the simulation of regional values of these quantities. The amplitude and phase of the first harmonic of the precipitation annual cycle also compares well with observations although less well over regions of sparse precipitation and/or high topography. In the model, the canopy plays a major role in processing moisture at the land surface indicating the importance of vegetation in climate. The canopy intercepts a large fraction of the precipitation and provides the medium for returning much moisture back to the atmosphere as evapotranspiration. Though important locally, the snow moisture reservoir plays a relatively minor role in the global moisture budget. It acts primarily as a storage and delay mechanism with winter precipitation released to the ground reservoir on melting. The ground moisture reservoir also plays a major role and processes a similar amount of moisture as the canopy, although in a different manner. The globally averaged model runoff compares well with observation-based estimates, although the model partitioning into surface runoff and drainage does not agree particularly well with the single available observation-based estimate. How moisture is processed at the land surface serves as a basis for model intercomparison and for understanding the modelled moisture budget and its variation and changes with climate change. Only the most basic quantities (precipitation, runoff, and partitioning of runoff into surface runoff and drainage) may be compared with observation-based estimates, however, and the establishment of more complete moisture budget remains an important need.     

Effects of Chronic Exposure to Sublethal Doses of Two Pesticides on Alkaline and Acid Phosphatase Activities in the Intestine of a Fresh Water Teleost,Channa striatus BL. (Channidae)

The effects of chronic exposures to sublethal concentration of two pesticides Carbaryl and Endosulfan on alkaline and acid phosphatase activities in the intestine of a fresh water teleost Channa striatus have been observed by exposing the fish for a period of two to thirty days to 10 ppm and 20 ppm of Carbaryl and 0.00075 and 0.001 ppm of Endosulfan. The inhibition of alkaline phosphatase activity has been dependent on the duration of exposure, concentration and the type of pesticide used. The acid phosphatase activity increased with the duration of exposure in higher concentration of Carbaryl and both the concentrations of Endosulfan. Endosulfan produced more pronounced effects than Carbaryl.     

New Data on the Olyutorskii Earthquake Acquired via SAR Interferometry

A coseismic displacement field based on SAR interferometry data was determined for the area of the April 20, 2006 Olyutorskii earthquake. The resulting image shows displacements toward the satellite (“uplifts”) to the northwest of the surface rupture area where the epicenters of most aftershocks lie. The displacement- affected area extends as far as the Vyvenka–Vatyna tectonic suture. We have developed a model for the rupture surface that is in agreement with the hypothesis of A.V. Lander and T.K. Pinegina stating that the largest displacements occurred along a fault northwest of the surface rupture zone; the fault dips southeast and is not exposed. The slip on the fault is close to a pure thrust type. These results furnish another confirmation of the fact that advanced satellite technologies can provide important additional information on the dynamics of seismic regions, especially where the existing observing networks are sparse.     

Inclusion of earthquake strong ground motion in a geographic information system-based landslide susceptibility zonation in Garhwal Himalayas

Garhwal Himalayas are seismically very active and simultaneously suffering from landslide hazards. Landslides are one of the most frequent natural hazards in Himalayas causing damages worth more than one billion US$ and around 200 deaths every year. Thus, it is of paramount importance to identify the landslide causative factors to study them carefully and rank them as per their influence on the occurrence of landslides. The difference image of GIS-derived landslide susceptibility zonation maps prepared for pre- and post-Chamoli earthquake shows the effect of seismic shaking on the occurrence of landslides in the Garhwal Himalaya. An attempt has been made to incorporate seismic shaking parameters in terms of peak ground acceleration with other static landslide causative factors to produce landslide susceptibility zonation map in geographic information system environment. In this paper, probabilistic seismic hazard analysis has been carried out to calculate peak ground acceleration values at different time periods for estimating seismic shaking conditions in the study area. Further, these values are used as one of the causative factors of landslides in the study area and it is observed that it refines the preparation of landslide susceptibility zonation map in seismically active areas like Garhwal Himalayas.     

GIS‐based route planning in landslide‐prone areas

Many parts of the world with young mountain chains, such as the Himalayas, are highly susceptible to landslides. Due to general ruggedness and steep slopes, roads provide the only way of transportation and connectivity in such terrains. Generally, landslide hazards are overlooked during route planning. In this study, in a test area in the Himalayas, various thematic layers, viz. landslide distribution, landslide hazard zonation, landuse/landcover, drainage order and lithology are generated and integrated using Remote Sensing–GIS techniques. The integrated data layer in raster form has been called a ‘thematic cost map’ and provides an estimate of the cost of route development and maintenance. The relative cost assignment is based on experts' knowledge. Route planning is based on neighbourhood analysis to find various movement possibilities from a pixel to its immediate neighbours. A number of patterns such as those analogous to movements in chess games have been considered. Two new neighbourhood patterns, named here Knight31 and Knight32, have been conceived in addition to commonly used Rook, Bishop and Knight patterns. The neighbourhood movement cost for moving from one pixel to a connected neighbour has been calculated for a 7×7 pixel window considering distance, gradient cost and thematic cost. Dijkstra's algorithm has been applied to compute the least‐cost route between source and destination points. A few examples are presented to show the utility of this approach for a landslide‐safe automatic route planning for a highly rugged hilly terrain.     

Geomagnetic Variation Anomalies In Peninsular India

Summary. Geomagnetic substorms recorded by an array of magnetometers over peninsular India have been analysed to investigate the subsurface electric configuration of the area. the study considered only night-time events when the external inducing field is uniform over the Indian peninsula and the conventional interpretational techniques of geomagnetic deep sounding can be readily applied. Contour maps of Fourier transform amplitudes and phases along with real and quadrature Parkinson arrows are presented. Their features reveal a complex anomaly pattern. the observed anomalies can be classified into: (i) southern peninsular anomalies, (ii) Palk Strait anomalies, (iii) Pondicherry rift anomalies, and (iv) anomalies in the central region. A large-scale induction process seems to be disturbed by localized perturbations. the prominent anomaly observed over the southern tip seems to have a direct relevance to the tectonic setting of the Indian ocean and adjoining areas.