The legend for land cover mapping was created by FAO in consultation with SUPARCO and representatives of the Crop Reporting Services. The Photo-keys of different land cover types were developed and which serve to illustrate the aspect on the ground (texture, tone, colour and reflectance) of the land cover units, present in the images. The final version of the legend is composed of 36 land cover classes aggregated into 13 main classes. The main 13 classes are as follows:
Orchards are the cultivated or maintained areas for the production of fruits, nuts, berries, or ornamentals. Orchards are divided into two subclasses on the bases of growth form namely tree orchards and shrub orchards. Orchards are always found in the agricultural irrigated area. An herbaceous crop could be present beneath the trees.
Areas used for the production of annual crops, such as corn, soybeans, vegetables, tobacco, and cotton. This class also includes all land being actively tilled. The differentiation of this class with rain fed crops is made on the basis of presence of channels, geographic location and local knowledge. Herbaceous crop irrigated and Herbaceous crop surrounded by Tree orchards are included in crop irrigated.
Crop marginal and irrigated saline are identified as those areas which are currently used for agriculture with low and unstable rainfall or higher rainfall areas intensively used, relative to user-capability, under existing population densities, traditional technologies and institutional structures. Crop marginal and irrigated include herbaceous crop irrigated saline fields and herbaceous crop rainfed in desert area. Herbaceous crop rainfed in desert areas are mostly found in the southern part of Sindh province, where the arid climate and the consequent shortage of rainwater allow crops to take place only when the occasional rainfall occurs and hence fields are sporadically active. Differentiation of this class with the class crop rainfed is made on the basis of geographic location and local knowledge. Herbaceous crops in saline area can resemble as reflectance to the class saline area. Its discrimination with saline area can be done on the basis of clear field’s pattern.
Crop marginal and irrigated saline are identified as those areas which are currently used for agriculture with low and unstable rainfall or higher rainfall areas intensively used, relative to user-capability, under existing population densities, traditional technologies and institutional structures. Crop marginal and irrigated include herbaceous crop irrigated saline fields and herbaceous crop rainfed in desert area. Herbaceous crop rainfed in desert areas are mostly found in the southern part of Sindh province, where the arid climate and the consequent shortage of rainwater allow crops to take place only when the occasional rainfall occurs and hence fields are sporadically active. Differentiation of this class with the class crop rainfed is made on the basis of geographic location and local knowledge. Herbaceous crops in saline area can resemble as reflectance to the class saline area. Its discrimination with saline area can be done on the basis of clear field’s pattern.
The term rainfed agriculture is used to describe farming practices that rely only on rainfall for water. Crop rainfed includes herbaceous crop rainfed and herbaceous crop rainfed in sloping land. The differentiation of this class with irrigated crops is made on the basis of the absence of channels, geographic location and local knowledge. Herbaceous crop rainfed in sloping land can be found only in the sloping mountainous areas of Hindu Kush and Himalayan region.
Forest is described as area characterized by tree cover natural or semi-natural woody vegetation, generally greater than 6 meters tall. Forest includes both natural and planted forest. In this class trees forest plantation, trees Closed, trees Open and mangroves are considered as subclasses. Tree forest plantation refers to governmental plantation. This class can be identified with large area and regular shape. Tree closed are a type of vegetation with tree percentage cover of more than 60%.The class closed trees occur in different parts of the country. It has woody natural vegetation, found both in broad as well as in needle leaves. Open trees are the type of vegetation with mandatory presence of trees and herbaceous growth forms with percentage cover varying from 10 to 60%. Mangroves are forest type exclusively found in the coastal areas.
The subclasses include river bank, wetlands, shrubs closed to open in wetland, tree closed in wetland and tree open in wetland. The subclasses are derived on the bases of soil and vegetation type. River bank is part of the river bed flooded during the rainy season (flood plain), the bed of the seasonal rivers is also included in this class. Wetlands are herbaceous vegetation with cover ranging from 60% to 100% found in flooded/ wet areas, sometimes associated with shrubs. Shrubs, closed to open, in wetland are found along the rivers and associated flooded areas in the vegetated portion of the river bank, made of shrubs with cover 20 - 100%. Tree closed in wetland are woody vegetation occurring along the rivers and associated flooded areas, with cover from 60 to 100%. Tree open in wetlands are the woody vegetation with cover ranging from 10 to 60%.
Rangelands are vast natural landscapes of grasslands, shrublands and woodlands. Areas characterized by natural or semi-natural woody and herbaceous vegetation with aerial stems, generally less than 6 meters tall, with individuals or clumps not touching to interlocking. These areas are not subject to intensive management such as tilling, but can be utilized for grazing. Shrub closed, shrubs open and herbaceous closed to open are the subclasses that are included in rangelands. Shrubs with a cover from 60 to 100% are considered as shrub closed. A layer of trees sparse (1-10%) could be present with shrub closed. Open shrubs are natural or semi-natural vegetation with shrubs ranging from 10 to 60 % and trees ranging from 1 to 10 %. They are found mainly on the hills of Pakistan, with both varieties of broad and needle leaves. Herbaceous closed to open is a type of vegetation where mandatory presence of herbaceous growth forms varies from 10 to 100% and optional presence of trees and shrubs of up to 10% of cover.
It defines all built-up areas (urban, industrial, airport etc.) with all vegetated areas linked to the built-ups such as gardens, golf courses, urban recreation parks, plots devoted to urban expansion etc.
This class describes areas that have very less natural and manmade vegetative cover. The subclasses include sand dunes and barren land. Barren land is bare soil area with very low density of shrubs and no agriculture activity. Sand dunes are made of low ridges or hillocks of drifted sand mainly moved by wind. The shifting sand is not covered by vegetation and, if present is negligible.
Sand Dunes with natural vegetation, bare rocks (with sparse vegetation) and desert flat plain are included in this class. These are areas where sparse vegetation could be present but the percentage coverage would be less than 10%. Sand dunes with natural vegetation are dunes that have permanent vegetation cover ranges from 1 to 40%. The vegetation cover causes a process of dune stabilization. According to the amount of vegetation cover, dunes are stabilized or semi-stabilized. Bare rocks (with sparse vegetation) are a class that contains less than 10% of growth forms. This class is based on the geographical location of the area that is declared as desert other than sand dunes.
Areas which are naturally covered with fresh or saline water such as river and lakes are grouped in this class. Wet areas are characterized by drainage and the consequent presence of sluggishly moving or standing water saturating the soil with sparse natural vegetation. The subclasses include mud flats, river perennial, salt lake, water bodies, saline area and water logged bare areas. The classes are derived on the basis of presence of water above surface. Mud flats are area with wet sand in proximity of mangroves forest and coastal area. River perennial is a part of the riverbed where there is a constant presence of flowing water throughout the year. Saline lakes are water bodies located near the coast where the water is brackish or saline. Lake shore is also included in the classes of water bodies and saline lake. Saline areas can show up as reflectance to the class herbaceous crop irrigated saline fields. In this case the field pattern is absent. Water logged bare area is low level land generally filled with a high water table. It must be always surrounded by agricultural area.
Snow permanent is the area characterized by year-long surface cover of ice and/or snow. Glaciers are permanent solid moving under its own gravity; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries.