Generation of stream length gradient index map using visual basic program-A case study from South India

Abstract

This study investigates the spatial variations of SL using visual basic computer program called R. Profiler. The graphical interface of R. Profiler allows the user to calculate the SL easily and draw the river long profiles. In order to check the efficiency and accuracy, R. Profiler is validated by using the drainage networks data of Kali River basin of southern India. The digitized data were converted into .txt format and imported into R. Profiler. Using query option, streams of third order and above have been selected and calculated the SL automatically. The calculated SL values of each portion of the river were converted into point shapefile and prepared the spatial map by using Inverse Distance Weighted (IDW) interpolation method available in ArcGIS 9.3. The results show that, R.Profiler is effective in calculating SL using the text data of ESRI line shapefile as an input.