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regression models, it has been clearly found that the relief and the area of the basin

register insignificant, negative relation, with the surface water resource
characteristics. Size and shape of the basin register a significant, positive relation.

Residuals show a higher positive deviation in most of the sub-watersheds of
Kanyakumari basin. The thematic maps used from the digital atlas for this analysis are

drainage, relief, and rainfall map.

Plate No ATM.15

Using the Digital Atlas thematic map plates the Land use/ land cover for
Nambiyar Basin is analysed and the alternate land use is suggested for sustainable

developement. The layers such as base map, drainage map, and ground water level

and land use map are used for analysis. From the spatial pattern, it is evident that the
groundwater level is relatively good in the observation wells of the foothill zones.

While the observation wells of the coastal zone show levels lesser than the mean sea
level as in the case of Vijayapathi and Ovari observation wells. The groundwater

fluctuation shows the relative recharge capacity, whereby the observation wells in
Kanyakumari basin is having good recharge in comparison with the wells of

Nambiyar basin. The change in the groundwater level for a period of 30 years also

shows a depletion of water level in a few of the coastal observation wells like
Colachel. The inland observation wells away from coast of Uppar, Radhapuram,

Lower Nambiyar and Valliyur kal also show depletion in their groundwater level, due
to their prolonged drought conditions. Thus it has been evidenced that the

groundwater level is depleting and so the present land use pattern of the basin may
deplete more of the water resources and so alternate agricultural methods like

horticultural, fodder and fuel plantations has been suggested. By suggesting alternate

land use patterns and methods the depleting groundwater resources can be sustainably
used.

Plate No ATM.16

The thematic map layers from the digital Atlas such as satellite image and land
use/ land cover are used estimate the increase in plantaion crops in kodayar

watershed. Temporal study has evidenced the land use / land cover change in which