other available environmental, demographic, and economical data in order to define a set of, mainly spatially-based, sustainability indicators. It is expected that analysing the changes in these indicators against land management and physical development polices and practices would provide recommendations into the most appropriate scenario for sustainable development.
Figure 1: Methodology for the detection and analysis of land use/cover changes
4.1 Satellite images and reference data
Landsat Thematic Mapper and Enhanced Thematic Mapper Plus (TM/ETM+) imagery (Figure 2) covering the study period of 1970 to present, will be used as the main data source for mapping land use and land cover. Other reference data such as aerial photography and topographic maps at nominal scale 1:25000 will be acquired for ground control and accuracy assessment.
Several images have already been identified and acquired to represent the land cover/use status in the 1980’s, 1990’s and 2000’s. One major concern over the use of satellite images of a tropical environment such as of Trinidad and Tobago is the existence of cloud cover, even during the dry seasons. Such a condition may limit the amount of information that may be extracted from these images, and would create information gaps and loss of valuable data (Al-Tahir et al 2008). One would expect that this problem would further be compounded when dealing with change detection as images from different dates are used to identify the extent and type of changes in the land cover and use in an area.
Several images have already been identified and acquired to represent the land cover/use status in the 1980’s, 1990’s and 2000’s. One major concern over the use of satellite images of a tropical environment such as of Trinidad and Tobago is the existence of cloud cover, even during the dry seasons. Such a condition may limit the amount of information that may be extracted from these images, and would create information gaps and loss of valuable data (Al-
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