Obtaining land-use information from a remotely sensed land cover map: results from a case study in Lebanon

The availability of land-use information allows decision-makers to develop short to long-term plans for the conservation, sustainable use and development of natural resources. Spatial land-use information often does not exist, whereas land cover information is mostly present in the form of maps derived from remotely sensed data. The latter could provide a basis for obtaining land-use information but there is currently no comprehensive methodology for how to obtain such information in a standardised manner. In Lebanon, with its wide variety of land cover types due to the diversity in landforms and variability in rainfall, a case study was carried out to try to develop a set of decision rules to obtain the dominant land uses from the existing 1:50,000-scale land cover maps. The development of the decision rules to allow such a transformation brought several problems to light concerning spatial and temporal variation of land cover, the accuracy of the input materials, the limitations of the developed decision rules and the complexity of the relation between land cover and land use. The decision rules were also analysed as to their general applicability for acquisition of land-use information and the implications for field survey data collection. Furthermore, quantification of the land cover and land-use classes allowed the examination of the nature of the land cover/use relationships in Lebanon. In addition, these data were compared to the FAO Production Yearbook statistics in order to link annual production estimates with the extent of land involved in the production of commodities. This comparison underlines the complexity of deducing land-use information from land cover data, especially where the land cover/land-use relation is weak and additional data is limited. Assumptions used to identify the spatial extent of certain land uses need to be thoroughly tested in the field for their validity as this is vital in obtaining reliable land-use information.