GEOSPATIAL APPROACH FOR RECONCILIATION OF NOTIFIED FOREST LANDS AT CADASTRAL LEVEL

摘要

Forest lands are unique natural resources which are vulnerable to degradation and encroachment. Spatial maps indicating ownership along with jurisdictional boundaries are important for enforcing forest conservation and protection. In this context, a pilot study was carried out to generate geospatial database for forest lands in collaboration with Karnataka forest Department (KFD) for reconciliation of notified forest lands at the cadastral level. The pilot study was carried out in four forest ranges covering 220 villages representing overall diversity in terms of terrain and forest types. The major input for the study included high resolution data (Cartosat-1, L1SS-1V), GAGAN based GPS, cadastral and notified forest land maps. GAGAN based GPS devise was used for collection of accurate GCPs. One set of GCPs were used in the photogrammetric block adjustment of Cartosat-1 stereo images for generation of DEM and orthorectification. Fusion of Cartosat-1 and LISS-IV data was earned out using Brovey technique. The results indicated reasonable positional accuracy of the orthoproducts showing potential use of low cost GAGAN based GPS for photogrammetry. The scanned village cadastral maps were georeferenced using second set of GCPs. The georeferenced cadastral maps were overlaid on the merged data to compare the extent of matching between parcel boundaries with field boundaries as manifested on high resolution data. The results are quite encouraging with 80.2 per cent of the cadastral maps showing better than 5.0 m accuracy along the field boundaries. Two season L1SS-1V and Cartosat-1 merged data was used for reconciliation of notified forest land boundaries. A comparative study was carried out to analyze the land use change within notified forest lands (As per KFD records) which indicated significant diversion of forest lands to agriculture. Further, decadal changes in the forest lands were analyzed using historical satellite database from 1965 to 2015 to study the diversion.