Assessing the Influence of Dykes on the Drainage Network of the Shivan River in North Maharashtra

The prominent linear dyke ridges outcropped in the Narmada-Tapi dykes’ swarm represent an intrusion in the Deccan Traps. Understanding the relationship among the underlying geological structures, the strike of the dykes, and the channel patterns is essential. Dykes act as obstructions to stream flow, causing diversions, and their geometry and patterns significantly impact the rivers and streams that drain and cross the dyke swarm zone. For this study, Google Earth images, LISS III images, and Cartosat DEM were used to delineate the Shivan basin and extract dyke features. The Shivan River basin is a sixth-order drainage system that reflects superimposed drainage systems within the Tapi dyke swarm zone. About 65% (169 km2) of its area is controlled by dyke orientation. The dyke ridges align predominantly in an East-West (E-W) direction, a pattern mainly followed by lower-order streams, which have developed an insequent, transverse drainage network within the dyke swarm zone. In the lower parts of the Shivan basin, where the number of dykes decreases, the drainage network follows the general slope and is oriented in a North-South direction. The Shivan River and its tributaries have partially adjusted to the dyke orientation, resulting in a transverse drainage pattern in areas characterized by parallel dyke ridges.

Characterizing Shorea robusta communities in the part of Indian Terai landscape

Shorea robusta Gaertn. f.（Sal）is one of the important tim-ber-yielding plants in India, which dominates the vegetation of Terai landscape of Uttar Pradesh state in India forming various communities based on its associations. The present study deals with delineation, map-ping and characterization of various communities of Sal （Shorea robusta） forests in Terai landscape of Uttar Pradesh, India ranging across over 16 districts. Field survey and visual interpretation based forest vegetation type classification and mapping was carried out as part of the project entitled ‘Biodiversity characterization at landscape level using remote sensing and GIS’. Indian Remote Sensing-P6 （Resourcesat-1） Linear Imaging Self Scanner-III satellite data was used during the study. The total area covered by different Sal forests was found to be approximately 2256.77 km2. Sal communities were identified and characterized based on their spectral properties, physiognomy and phytosociological charac-teristics. Following nine Sal communities were identified, delineated and mapped with reasonable accuracyviz.,Chandar,Damar, dry plains, moist plains, western alluvium, western alluvium plains, mixed moist deciduous, mixed dry deciduous andSiwalik. It is evident from the area estimates that mixed moist deciduous Sal is the most dominant commu-nity in the region covering around （1613.90 km2）, other major communi-ties were found as western alluvium plains Sal （362.44 km2）, mixed dry deciduous Sal （362.44 km2） and dry plains Sal （107.71 km2）. The Terai landscape of Uttar Pradesh faces tremendous anthropogenic pressure leading to deterioration of the forests. Community level information could be used monitoring the status as well as for micro level conserva-tion and planning of the Sal forests in Terai Landscape of Uttar Pradesh.

Pennar (Somasila) to Cauvery (Grand Anicut) Inter Basin Water Transfer Impact Assessment on Land Use/Land Cover Environment

As a part of the National Water Development Authority (NWDA) proposal, the linking between Pennar and Cauvery is put forth with a single purpose of conserving water to the maximum extent possible. The present study covers with land use/land cover (LU/LC) along the alignment study area 17215.68 sq·km. All the details of these features have been studied using IRS-P6, LISSIII data to analyze the effect of land use and land cover. The land use and land cover data are classified into 9 categories such as crop land, current fallow, forest, plantations, built-up land, water bodies, scrub land, sandy area and others. The total area going to be capsized is 17215.68 sq·km out of which 10105.96 sq·km is proposed command area. The 244 villages have to be rehabilitated due to this canal whereas about 4597 villages will enjoy the fruits of this canal in the form of drinking water, ground water recharge and as an additional source of irrigation as well. The study indicated current fallow land of 5340.14 km2 and 6307.98 km2 of cropland can be brought under cultivation which is more than what NWDA estimated land that can be benefitted.

Long-Time Shoreline Monitoring of the Vellar Estuarine Complex,Southeast Coast of India:Using Multispectral Satellite Data

The present study was carried out to track the path of Vellar estuary over a period of 38 years （1970-2008） and also to detect the impact of tsunami on estuarine complex of the Vellar estuary. Visual interpretation techniques were employed by using muitispectral data of Landsat TM （1991） and IRS-P6 LISS III （2004, 2006, and 2008） to delineate shoreline changes in the VeUar estuarine complex. Results clearly revealed the changes that occurred along the estuarine path over the period, and severe erosion was noticed in the seaward side of the MGR Thittu and accretion, along the estuarine mouth. It is also visible that there is clear river path shift in the river course. Although the sandbar formation was seen with only little morphologic modification up to 2004, the Indian Ocean tsunami that struck this coast （26 December, 2004） distorted the sandbar of the Vellar estuarine mouth; however, the 2006 satel- lite images confirmed that the sandbar was formed again to its original structure as that of before the tsunami.