GIS and Remote Sensing for Natural Resource Survey and Management Data Processing The IRS P6 satellite data were geo-referenced and suitable Image enhancements are applied to facilitate the delineation and interpretation of different thematic information. Data Interpretation Visual and digital interpretation methods were used to prepare pre-field interpreted map. The satellite data is interpreted based on photo elements like tone, texture, size, shape, pattern, aspect, association etc. These pre-field interpreted maps and digitally enhanced satellite data are used on the ground to identify different elements of various themes. Field Verification and Data Collection Suitable field sampling designs in terms of line transects/ quadrants are used to assess the interpreted elements and relate with satellite data. The field data collections are aided by GPS in order to locate the ground verification points on the image and for further incorporation of details. For the all the sample collection and field points visited attribute information on vegetation, geomorphologic, soil and topographic parameters are also collected. The detailed soil-site study was undertaken in each soil-mapping unit by general traversing and by collecting surface soil, minipit and soil profile observations at intervals depending on soil variability The sample points were decided based on the geological / Geomorphological / soil heterogeneity mapped from the satellite data. Finalization of Maps Based on the pre-field interpretation, ground truth verification and available secondary information final maps were prepared in 1: 25000 scales. Towards this both visual and digital approaches are conjunctively used.  Themes Specifications: Land use Land cover The land use and land cover map is prepared using RESOURCESAT LISS IV satellite data. The classification scheme was designed keeping in view of the management practices addressing each land use/ land cover parcel, amenability of these parcels for identification/mapping in LISS IV dataset. Under the Level-I classification, Built up, Cultivated areas, Woody vegetation, Grasslands, Wastelands, Wetlands and Water bodies were segregated. In addition subclasses of Level-I LULC classes observed based on spectral satellite data and were evaluated on the ground, to characterize them as information classes. All the LULC classes were visually interpreted based on tone/texture, contextual and ground information. The major information class in the study area is ‘built up areas’ was consisting of urban and rural fringe landscapes and the urban built up areas were dominated by residential, mixed residential and industrial areas. The rural landscape essentially consisted of settlements, camel camps and cultivated areas. Statistical data of community wise built up area was generated and analyzed. Vegetation The vegetation cover map is generated using IRS Resourcesat LISS III & IV. The vegetation in the study area is regulated by desert climate, seasonality, physiographic, geomorphologic and soil regimes. The vegetation is broadly demarcated into natural and managed vegetation. The natural vegetation mainly consisted of formations of Mangroves, Prosopis, Leptadenia. The managed vegetation mainly consisting of avenue plantations, grasslands, lawns, golf courses and palm /mixed plantations. Phyto-sociological analysis was carried out after collecting sufficient number of sample data from the natural vegetated areas. The vegetation mainly mangroves, Prosopis, Laptadenia are further stratified into dense and open canopy density classes. Further different categories of vegetation under each of the community has been extracted and analyzed to understand the percentage of vegetation present to that of vacant land. Such information on spatial distribution in qualitative and quantitative terms would be useful in further exploring and analyzing the aspects of biodiversity and ecological conservation Soils The soil is mapped using remote sensing satellite data IRS- P6 LISS IV. The soils of the study area were classified upto series level and their association’s level as per the Keys to Soil Taxonomy (Soil survey staff, 2003). . Essentially soil survey is a study and mapping of soils in the field. It is the systematic examination, description, classification and mapping of soils of an area and it comprises of a group of interlinked operations involving
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