Karnataka

In this study, NASMO model, a rainfall-runoff method, which uses the SCS method to determine effective rainfall, the linear reservoir method to route the runoff over land and the modified Puls method to route the runoff in the stream have been applied for hydrological modeling of the Malaprabha catchment in Karnataka. Geographical Information Systems (GIS) has been applied to derive the catchment characteristics like shape, size, slope and land use pattern.

Organiser: YETI Student Volunteers

Venue: Indian Institute of Science, Bangalore

Description:

Young Ecologists Talk & Interact (YETI) is a conference for students and researchers working in the discipline of ecology in India. This event is meant to serve as a friendly, inspiring platform for early-career ecologists to present and discuss their work, exchange ideas, and may be even strike up collaborations with contemporaries from all over the country.

The study applies TOPMODEL (Topography Model) to the Malaprabha catchment of Krishna river basin in Karnataka to simulate the daily flows at Khanapur site. The catchment area of Malaprabha up to discharge measuring site Khanapur is 520 sqkm. The model uses topographic index for the formation of runoff through development of a Digital Elevation Model (DEM) by interpolating the contours in the basin at 300 m grid size.

The study attempts to find out the effects of geomorphology on watershed runoff response in the Devak basin and tries to identify the parameters that are more closely related to runoff. A chief objective of the study is to regionalize the hydrologic models describing the rainfall-runoff process. 

The advanced knowledge of geomorphology of the region is of importance in the field of flood control measures and engineering projects, since geomorphological characteristics of river basins in mountainous areas affect runoff processes and formation of floods in the areas.

The study develops a regional conceptual catchment water balance model for five catchments in the Western Ghat region of Karnataka. The model can be used to estimate the water yield from ungauged catchments located in the region.

The water yield is an integration of discharge as a function of time for a specified duration and reflects the volumetric relationship between rainfall and runoff. The estimation of water yield is required for solution of water resources problems normally encountered in design of storage facilities. It is of use in understanding the water availability for agriculture, industrial and drinking purpose as also for estimating the dependable water supply for power generation and irrigation projects.

The study uses HEC-RAS to analyse the water surface profiles of Malaprabha river system upto Khanapur for different combinations of discharges through various reaches of the river system. The river system is divided into eleven reaches, and forty one cross sections have been measured and interpolated within these reaches.

Discharge values have been assigned for different reaches according to the ratio of contributing area for each reach. The bridge across the river at Khanapur is reproduced in the modeling system to test its capabilities. Various return period floods have been allowed to pass through the river system to compute the individual water surface profiles.

The study estimates the average soil loss using the Geographic Information Systems (GIS) tool of Integrated Land and Water Information Systems (ILWIS) and the Universal Soil Loss Equation (USLE) methodology for the Hire nadi catchment, in Yelbarga taluk, Koppal district of Karnataka, under different conditions.  

Scientific planning for soil conservation and water management requires knowledge of the relations among factors that cause and prevent soil and water loss.  Controlled studies on field plots and small watersheds have supplied vital information regarding these complex factors and their interrelations.

The hydrological study for the experimental representative basins, Ghataprabha and Malaprabha, of the Krishna river basin attempts to standardize and develop methodologies for providing solutions for understanding and solving various hydrological problems of the hard rock regions of India.

Representative basins are basins, which are selected as representative of a hydrological region within which hydrological similarity is presumed and can be used for intensive investigation of specific problems of the hydrological cycle. This can then take a wide-ranging role representing a broad area to which the data can be transferred. 

The study analyses the surface and groundwater quality of Ghataprabha representative basin during pre-monsoon and post-monsoon seasons. It looks at the primary impact of land use and cropping pattern on water quality using physico-chemical analysis, geo-chemical classification of groundwater samples and monitoring of groundwater quality.

Streeter-Phelp’s model is applied to understand the variation of dissolved oxygen along the course of the river from a point source. The study attempts to understand the impact of irrigation return-flow and use of pesticides, fertilizers & manures on surface and groundwater quality. The literature review offered indicates a dearth of studies on the subject for hard rock catchments and puts forward the need to do basin-wide as against area-wide studies.

The study deals with the estimation of hydrological soil properties of the area of Lokapavani River in KR Sagar Command in Mandya district of Karnataka. The properties determined are soil texture, porosity, saturated hydraulic conductivity, specific gravity and soil moisture characteristics.

The disturbed and undisturbed soil samples from eighteen locations along different depths were collected and analyzed. Eighty-five disturbed soil samples were used to determine the grain size distribution, porosity, specific gravity and soil moisture characteristic curves with the help of electromagnetic sieve shaker, master sizer, GeoPyc and pressure plate apparatus. Twenty undisturbed soil samples were used to determine saturated hydraulic conductivity with ICW Permeameter.