Rao, D.P. 
  
pattern and crop yield, occurrence of hazards and socio-economic conditions. 
Included under land use/land cover parameters are: changes in the number and 
areal extent of surface water bodies, spatial extent of forest and other 
plantations, wastelands and cropped area. The vegetation density and vigor 
have been assessed using vegetation index (VI) generated from IRS -1A/-1B 
LISS-II or IRS-1C/-1D LISS-III data. 
9. A CASE STUDY 
In order to demonstrate the approach, an example of such an approach used in 
a watershed in the semi-arid region of southern India is presented here. The 
Pitlam watershed was selected for the study owing to its low (897mm) and 
erratic rainfall, recurring drought, land degradation, poor irrigation facility and 
poor literacy). Covering an area of 17,218ha, the test site lies between 18°10" to 
18°17" N and 77°35 to 77°45’ E and forms parts of Pitlam block (an 
administrative unit) of Nizamabad district of Andhra Pradesh, Nanded district of 
Maharastra. Lithologically, the are comprises of granite-gneissic complex and 
basalt. Most of the area comprises of denudation slope and lower plateau which 
is interspersed with burried pediplain, mesa inselberg and pediment. The area is 
drained by the river Nallavagu and its tributaries. 
9.1 Land and Water Resources 
For generating information on land and water resources IRS-1B LISS-II data in 
the form of False Colour Composite (FCC) prints at 1:50,000 scale acquired 
during October, 1992, and February and May, 1993 was were used following the 
approach described in the Section 8.2. Denudation slope, plateau, pediplain, 
buried pediplain-shallow and medium, pediment, mesa and inselberg , as 
mentioned earlier, comprise the geomorphic units (Fig.- 2). While inselberg, 
mesa, pediments favour more run-off, the buried pediplain and plateau with 
considerable thickness of weathered material are favourable for groundwater 
development. Denudation slopes, inselbergs and mesas have, however, poor to 
nil ground water potential. Coarse loamy Lithic Ustorthents and Loamy-skeletal 
Typic Ustochrepts; Fine Vertic Ustochrepts and Fine loamy Typic Ustochrepts, 
and Fine Udertic Ustochrepts and Fine loamy Udic Ustochrepts comprise the 
major soil categories of the watershed (Fig.-3). Owing to rugged and slopy 
nature terrain, shallow and gravelly soils, fairly large area of the watershed is 
not supporting crops.The kharif is the major crop and covers an estimated 
7,289ha comprising 42.33% of the watershed (Fig.-4). The rabi crop is, 
however, taken wherever assured irrigation through ground water /tank is 
available and covers1049ha(Fig.-4). The area under double crop is only 308ha or 
1.79% of the total area. Further, an equally large area (8,250ha) comprising 
  
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.