RESULTS AND DISCUSSIONS

Land use analysis was carried out using Landsat series and IRS series of satellite data to understand the landscape dynamics of Sagara taluk and the results area as presented in Figure 6 and Table 1. Land use analysis between 1973 and 2012 indicate that forest cover has reduced from 57.3% in 1973 to about 45.5% in 2012.

1973	1990
2001	2012

Figure 6.  Land use dynamics

Table 1. Land use dynamics of Sagara (all units in %)

Ground water dynamics were assessed in the wells located in catchments and in the vicinity of Baruru, Lavigere, Pandavarakoldu, Hosagunda, Yelakundali lakes respectively and is depicted in Figure 7. The results indicate the availability of water in wells is correlated with its proximity to forests and lakes, evident from lower deviations. Wells farther away from lakes and also forested catchments, had poor ground water table, indicating the lower quantum of water in the well with large variations across seasons.

Discharges were measured using area velocity method at Varadamoola, Bilisiri, Hulkodu, YenneHole and Varada are presented in Figure 8. Discharges were normalized and compared across seasons w.r.t catchments. Results indicate streams at Hulkodu (i.e., sacred grove with pristine evergreen forest cover) were perennial with higher water yield during post and pre monsoon periods compared to other (with degraded landscape and mixed land use types). Intermittent stream flows of 7 to 11 months at Varadamoola, Bilisiri, Yennehole and Varada confirm the silent role played by native vegetation in sustaining water in streams. Average seasonal flow for each of the gauged streams were quantified and compared as depicted in Figure 9 and Table 2, Comparative assessment of the 5 gauging stations showed that Hulkodu had richer water resource throughout with nearly 5 times higher availability in the post monsoons and 10 times higher availability in the pre monsoon (Table 2).

Figure 7.  Ground Water Dynamics

Figure 8.  Stream flow Dynamics

Figure 9.  Comparative assessment of stream flows

Table 2. Comparative assessment (all units in mm)