Requisites and methodologies in digital terrain models production

Land management and analysis deserve a deepened knowledge of every factor influencing it processes and dynamics particularly in areas with high morphological complexity as mountain areas, this knowledge has to be extended to he third dimension in order to acquire a more complete comprehension of the phenomena. In these years simultaneously with the evolution in informatics the employment of digital terrain models has increased in different fields of application in addition to the traditional use in orthoimage production. Today digital terrain models are used in hydraulic modelling, road projects, risk assessment, forestry, and in specific application as mobile communication, visibility assessment, forest fire monitoring systems… Digital terrain models have ceased to be a by-product in orthorectification process becoming a real product in cartographic production, so they need technical rules defining production methodologies and quality control standards.