Development of a Spatial Reference (System) Database
Field crop plot boundaries can be extracted from high-resolution images with spatial resolution less than 2.5 m from satellites like Cartosat, QuickBird, etc. The village maps along with survey numbers obtained from respective states’ departments geo-referenced using control points like natural features, roads, etc. and the coordinates obtained from DGPS were used to increase the positional accuracy. Crop plots were extracted from high-resolution natural color composite images from Google Earth. A controlled mosaic of crop plots for each village developed in GIS environment was converted to geo-fenced map tile and loaded on to smartphone powered with suitable application for automatic navigation and recording the information along with photographs in the field. Farmers in each village were informed about the process and cooperation was sought. Field inventory carried out in Rabi was kept as basic reference of crop plots of different farmers. Android application was modified to reduce the mapping of plots without crops in subsequent season. The data generated in each season was systematically organized in QGIS for visualization and spatial analysis. Farmers not only cooperated but also felt that the process is useful so that they can have reference of crop area and type.