Comparison between the accuracy of geomorphological map using traditional and analytical photogrammetry methods (Case study: Harzand chai watershed)

Aerial images are systematically utilized in most scientific contexts to undertake exploration and measurement operations. Image matching techniques for the acquisition of the ground truth in order to create thematic maps have been always faced difficulties and challenges. In this research, the LPS module from the ERDAS Imagine9.2 software
was used to develop geomorphological landforms maps of the Harzand Chai watershed. The methodology used was based on analytical photogrammetric techniques (Two Dimension Affaine) using aerial photographs (1:40000). Harzand Chay watershed geomorphological landforms maps, were prepared using both traditional and photogrammetry methods.Prepared map by photogrammetrical method (Two Dimension Affaine), was compared after field visiting and matching type facies with the acquisition of the ground truth, with the map which prepared by conventional method that is used for creating thematic maps in our country. Geomorphological landforms map has been prepared for the test to assess 100 points on maps provided by the software ERDAS Imagine9.2 about 62 points of the set and then using ground positioning system (GPS) were harvested and the characteristics of each were done. Stratified Random Sampling and test method was used by ERDAS Imaginge 9.2 for examin two prepared maps.The resultant map was then matched with the real features and compared with the map developed by traditional methods used in the thematic mapping process in Iran. According to the findings of the statistical test, the percentage of the total accuracy for
the geomorphological landforms map developed by the analytical photogrammetry technique was %95. The Kappa Index value for this map was estimated to be 0.9. These values for the geomorphological landforms map created by the conventional method were obtained %84 and 0.76 respectively. Therefore, the geomorphological landforms map created by the analytical photogrammetry was selected as the best representation of the geomorphological features of the Harzand Chai watershed.