STUDY AREA

The study area considered here is Lakshmanatirtha  catchment (fig1) of river Cauvery. The river originates at Bramhagiri hills [42, 43] near Irupu, of Madikeri, and meets Krishnarajasagara in Mandya [44, 45]. Extending from 12O6’ N to 12O45’ N and 75O38’ E to 76O34’ E the catchment is spread across four districts of Karnataka state namely Kodagu, Hassan, Mandya and Mysore, with an area of 3969 km2. The altitude (fig2) of the terrain varies from  700m at plains and goes up to 1600m towards the Ghats. Geologically soils contain gravelly to well drain clay to loamy soils and rock types include Gneiss, Granite. The basin receives most of its rain (fig 2) from the South-West monsoon during June to October; rainfall in the region varies from as low as 750mm at the plains to over 3000mm at the Ghats. The temperature (fig4) in the basin on an average varies from as low as 14Oc in January month to as high as 32Oc in May month. Agriculture and horticulture activities includes paddy cropping during monsoon, ragi, maize, sugarcane, tobacco, areca nut, coconut, ground nut, other pulses, oil seeds and food crops .The population density (fig 5) in the basin has increased from 272 persons per square kilometre in 2001 to 288 persons per square kilometre in 2011at a rate of 5.8% in a decade.

Fig. 1: Study Area