The National Remote Sensing Agency (NRSA) conducted a land use survey using Remote Sensing Technique in the year 1988-89 at the behest of the Planning Commission in which they had classified the land by visual interpretation technique and digital techniques into twenty two-fold. The definitions of the 22 categories adopted by them are as follows:
Built up land It is defined as an area of human habitation developed due to non-agricultural use and that which has a cover of buildings, transport, communication utilities in association with water vegetation and vacant lands.
Agricultural land It is defined as the land primarily used for farming and for production of food, fibre, and other commercial and horticultural crops. It includes land under crops (irrigated and un-irrigated), fallow, plantation, etc.
Crop Land It includes those lands with standing crop (per se) as on the date of the satellite imagery. The crops may be of either Kharif (June-September) or Rabi (October – March) or Kharif Rabi seasons.
Fallow land It is described as agricultural land which is taken up for cultivation but is temporarily allowed to rest un-cropped for one or more seasons, but not less than one year. These lands are particularly those which are seen devoid of crops at the time when the imagery is taken of both seasons.
Plantations It is described as an area under agricultural tree crops, planted adopting certain agricultural management techniques. It includes tea, coffee, rubber, coconut, arecanut, citrus, orchards and other horticultural nurseries.
Forest It is an area (within the notified forest boundary) bearing an association predominantly of trees and other vegetation types capable of producing timber and other forest produce.
Evergreen/Semi-evergreen forest It is described as a forest, which comprises of thick and dense canopy of tall trees, which predominantly remain green throughout the year. It includes both coniferous and tropical broad-leaved evergreen trees. Semi-evergreen forest is a mixture of both deciduous and evergreen trees but the latter predominate
Deciduous forest It is described as a forest which predominantly comprises of deciduous species and where the trees shed their leaves once in a year.
Degraded forest or Scrub It is described as a forest where the vegetative (crown) density is less than 20% of the canopy cover. It is the result of both biotic and abiotic influences. Scrub is a stunted tree or bush/shrub.
Forest Blank It is described as openings amidst forests without any tree cover. It includes openings of assorted size and shapes as seen on the imagery.
Forest Plantations It is described as an area of trees of species of forestry importance and raised on notified forest lands. It includes, eucalyptus, casuarina, bamboo, etc.
Mangrove It is described as a dense thicker or woody aquatic vegetation or forest cover occurring in tidal waters near estuaries and along the confluence of delta in coastal areas. It includes species of the general Rhizophora and Aviccunia.
Wastelands It is described as degraded land, which can be brought under vegetative cover with reasonable water and soil management or on account of natural causes. Wastelands can result from internal/imposed constraints such as, by location, environment, chemical and physical prosperities of the soil or financial or management constraints (NWDB, 1987).
Salt-affected land The salt-affected land is generally characterised as the land that has adverse effects on the growth of most plants due to the action or presence of excess soluble or high exchangeable sodium. Alkaline land has an exchangeable sodium percentage (ESP) of about 15, which is generally considered as the limit between normal and alkali soils. The predominant salts are carbonates and bicarbonates of sodium. Coastal saline soils may be with or without ingress or inundation by seawater.
Waterlogged land Waterlogged land is that land where the water is at/or near the surface and water stands for most of the year. Such lands usually occupy topographically low-lying areas. It excludes lakes, ponds and tanks.
Marshy/Swampy land Marshy land is that which is permanently or periodically inundated by water and is characterised by vegetation, which includes grasses and weeds. Marshes are classified into salt/brackish or fresh water depending on the salinity of water. These exclude Mangroves.
Gullied/Ravenous land The gullies are formed as a result of localised surface runoff affecting the friable unconsolidated material in the formation of perceptible channels resulting in undulating terrain. The gullies are the first stage of excessive land dissection followed by their networking which leads to the development of ravenous land. The word ‘ravine’ is usually associated not with an isolated gully but a network of deep gullies formed generally in thick alluvium and entering a nearby river, flowing much lower than the surrounding high grounds. The ravines, are extensive systems of gullies developed along river courses.
Land with or without scrub They occupy (relatively) higher topography like uplands or high grounds with or without scrub. These lands are generally prone to degradation or erosion. These exclude hilly and mountainous terrain.
Sandy area (costal and desertic) These are the areas, which have stabilised accumulations of sand in-site or transported in coastal riverine or inland (desert) areas. These occur either in the form of sand dunes, beaches, channel (river/stream) islands, etc.
Baren rocky/Stony waste/Sheet rock area It is defined as the rock exposures of varying lithology often barren and devoid of soil cover and vegetation and not suitable for cultivation. They occur amidst hill forests as openings or scattered as isolated exposures or loose fragments of boulders or as sheet rocks on plateau and plains. It includes quarry or gravel pit or brick kilns.
Water bodies It is an area of impounded water, areal in extent and often with a regulated flow of water. It includes man-made reservoirs/lakes/tank/canals, besides natural lakes, rivers/streams and creeks.
River/Stream It is a course of flowing water on the land along definite channels. It includes from a small stream to a big river and its branches. It may be perennial or non-perennial.
Reservoir/Lakes/Tanks/Canal It is a natural or man-made enclosed water body with a regulated flow of water. Reservoirs are larger than tanks/lakes and are used for generating electricity, irrigation and for flood control. Tanks are smaller in areal extent with limited use than the former. Canals are inland waterways used for irrigation and sometimes for navigation.
Others It includes all those, which can be treated as miscellaneous because of their nature of occurrence, physical appearance and other characteristics.
Shifting Cultivation It is the result of cyclic land use practice of felling of trees and burning of forest areas for growing crops. Such lands are also known as Jhum lands.
Grassland/Grazing land It is an area of land covered with natural grass along with other vegetation, often grown for fodder to feed cattle and other animals. Such lands are found in river beds, on uplands, hill slopes, etc. Such lands can also be called as permanent pastures or meadows. Grazing lands are those where certain pockets of land are fenced for allowing cattle to graze.
Snow-covered /Glacial area It is snow-covered areas defined as a solid form of water consisting of minute particles of ice. It includes permanently as on the Himalayas. Glacier is a mass of accumulated ice occurring amidst permanently snow-covered areas.