News and Articles

The report attempts to do a comparison of single and multiple flow direction algorithms for computing topographic parameters in TOPMODEL. Topography is an important factor that influences the physical phenomenon of rainfall-runoff. Undeniably, it plays a primary role in the gravity drainage within a basin. In the last decade, ever-developing computer techniques associated with the greater availability of terrain data in digital form has favored the production of physically based models, which have spatial variability of topography built into their structure.

The report deals with the estimation of geomorphology parameters for small catchments using Geographical Information Systems (GIS). Stream channel morphology is literally the study of stream channel form and structure, but generally it is taken to mean their form and structures regarded as a whole or their collective morphology features. Systematic analysis of morphometry of any drainage basin and its stream system is of great importance in understanding the hydrological behavior of the basin.

The report presents the seasonal mapping of water bodies along the Andhra coast using satellite data to analyze the pre-monsoon and post-monsoon variations in the reservoirs. Water resources development be it construction of reservoir, anicut or irrigation canal, calls for mapping of the various water bodies to throw light on its behavior in different seasons in order to plan a judicious water management scheme.

Remote sensing methods are considered to be more appropriate than conventional methods for collection of such information owing to their capability to provide broad synoptic and repetitive coverage of the area in a multi-spectral mode.

The study focuses attention on the use of inverse modeling technique for estimation of rainfall-recharge in a coastal aquifer. MODINV (Modular Inverse Model), which is software for parameter optimization of 3-D groundwater flow model, MODFLOW is applied to the Central Godavari delta in Andhra Pradesh to estimate the distributed rainfall-recharge during monsoon season.

In this report an attempt has been made to estimate the mean monthly reference crop evapotranspiration (ETo) for the Krishnai Irrigation Project in Assam. To undertake this analysis, the mean monthly climatological and physiographical data for the period of 1986 to 1994 has been collected from the Meteorological Department, Borjhar, Assam.

The report deals with the transportation behavior of lindane, a pesticide used commonly in the agricultural and public health sectors in India, through sandy and loamy soils. The contamination of groundwater by pesticides is a worldwide problem because of their tissue degradation and carcinogenic nature. They are bio-accumulative and relatively stable and therefore, require close monitoring.

The pesticides used for agricultural, forestry and domestic activities leach into the groundwater and therefore, it is very important to study their transportation behavior in different types of soil media.

The study deals with the distribution of heavy metals on sediments under different flow conditions in the river Hindon. The river is subjected to varying degree of pollution caused by numerous untreated waste outfalls of municipal and industrial effluents.

The report deals with development of reaeration coefficient for Indian condition using mathematical approach and field studies. Of the various constituents, which determine the quality of water, Dissolved Oxygen is the most important parameter indicating the health of a stream. There is a continual replenishment (reaeration) or utilization (deoxygenated) of Dissolved Oxygen due to inflow of waste load at different points in the stream. When a waste load is discharged into a flowing stream, it is mainly subjected to advection, dispersion and reaction kinetics. Waste Load Allocation (WLA) studies provide information to assist in making effective decisions on levels of treatment required for a source or sources of pollutant loads.

The report attempts drought characterization in arid and semi-arid climatic regions of India. Drought frequency and intensity are a function of the dimensionless climatic parameter derived as a ratio of mean annual potential evapotranspiration to mean annual precipitation (Ep/Pa).

The report presents a study on the Sagar lake wherein the various water balance components like inputs and outputs have been quantified to visualize the influence of these parameters on the storage changes. Lakes play an important role in shaping the hydrological, ecological and environmental balance of the region by developing the flora, fauna and habitation of the aquatic biota. Like other lakes, Sagar lake too faces manifold problems of siltation and deterioration of water quality, thus threatening its survival.