COMPARISON OF A GEOGRAPHICAL INFORMATION-SYSTEM VERSUS MANUAL TECHNIQUES FOR LAND-COVER ANALYSIS IN A RIPARIAN RESTORATION PROJECT

Few studies have addressed the benefits and costs of computerized geog raphical information systems (GIS) as compared to manual methods of ca rtographic analysis. However, GIS require substantial investment in eq uipment and personnel which is of particular importance to small or fi nancially strapped resource management agencies. In this case study, l and cover maps created as part of a riparian restoration research proj ect were used to compare the time-costs involved in calculating land c over areas with a GIS and manually with a planimeter and dot-grid. Sim ple modeling of riparian forest restoration potential was also perform ed to investigate the GIS value for restoration planning. While estima tes of land cover areas were similar for the two methods, GIS time-cos ts were many times higher than manual technique time-costs. Developmen t of even a simple modeling procedure for restoration planning proved difficult and time-consuming. Modeling results, although useful, also require validation. As the complexity of modeling increases, the need for technical expertise and analyst time increases without negating th e need for validation. Natural resource managers should carefully eval uate long-term benefits and costs before adopting a GIS for riparian r estoration planning.