Precipitation Used as Key Factor in Tapered Line Based River Representation

Abstract

GIS and cartography represent two different study areas but both of them share the map concept. Nowadays, most GIS software incorporates advanced representation and labeling possibilities, and thanks to the database, which is an essential component of any geoinformation system, there are multiple symbolization possibilities, using the stored data. Taking into account this symbiosis between the two components of modern GIS: analysis and advanced representation this study wants push further the cartographic possibilities of them taking advantage of their analysis and modelling part. Through this study we wanted to develop and test a method for river symbolization in which the river's line width to be proportional with the average precipitation amount at every part of the river. The idea of this study came by working with hand drawn historical maps in which this type of representation is common and very suggestive. Although there are some interesting approaches which want to symbolize river courses based on data, this type of approach presented in this study has not been found. The result obtained from a situation where inaccuracies are inevitable due to very different data sources: a recent DEM with 25m resolution and a map from the beginning of the 20th century with scale of 1: 300000, has shown that this method based on modeling, analysis and GIS operations can be used successfully to have a more accurate, more real and eye catching symbolization of watercourses.