ارزیابی شاخص موقعیت توپوگرافی (TPI) در زون سنندج - سیرجان و زاگرس شکسته

Automatic analysis of morphometric of topography is one of the new sections and unprecedented internal studies. Due to this fact, the validation of this type of studies are also similarly important to their assigned position. Hereof, the leading research, analysis of the topography position index (TPI) automatically in two regions of Sanandaj – Sirjan zone and broken Zagros zone to achieve most correct results, were studied. In this study, according to verify and adaptation with condition of observations was used of Dickson & Beier within through of the other methods. After preparing of TPI layer with separation to 4 classes (ridgetop, steep slope, flat-gentle slope and canyon bottom) approach by Dickson & Beier from DEM layer with a resolution of 10 m of the total Sahneh township in Kermanshah province, in the next step typically from two parts of the geomorphologic Zagros region selected two part with dimensions of 6.07 × 6.07 km. In the final part of the project as well as the results of the topographic position index with respect to satellite images and field visits. The results represent the perfect match the values of the TPI = 1, with valleys and Canyon (Exist of Drainage Network), TPI = 2, with the residential part of the crop, and the slope gentle, TPI = 3, fitted with steep slopes and sparse vegetation and TPI = 4, with ridgetop. In two parts areas of steep slope has been included maximum area   parts of the both regions (pilot) and then the landforms of slope gentle and the ridgetop and finally also canyon bottom as well as the minimum area.
Introduction
Landform is a feature of land or face of its a complicated that formed it to be formed by natural processes formed that it can be described and defined with features of distinctive, and present of various landforms and diversity of their controlled mainly by changes in the shape and position of the land. So, classify and identify different areas according to morphometric characteristics is essential. In this study, accuracy and TPI model classes at the first by given the actual conditions, and in the next measured in accordance with a resolution of DEM. The present research with new assumptions, the validity of this model in two different regions of Zagros and given the realities of the region, work epigraph put.
Materials and Methods
In this part, analysis of the topography position index (TPI) automatically in two regions of Sanandaj – Sirjan zone and broken Zagros zone to achieve most correct results, were studied. After preparing of TPI layer with separation to 4 classes (ridgetop, steep slope, flat-gentle slope and canyon bottom) approach by Dickson & Beier from DEM layer with a resolution of 10 m of the total Sahneh township in Kermanshah province, in the next step typically from two parts of the geomorphologic Zagros region selected two part with dimensions of 6.07 × 6.07 km. In this study, according to verify and adaptation with condition of observations was used of Dickson & Beier within through of the other methods.
Results and discussion

Sanandaj – Sirjan zone (A)

By analysis this area to the conclusion that 8.52 % of the zone is valleys, 22.74 % is gentle slope, 57.64 % is steep slope and 11.1 % ridgetop included. By analysis of the drainage network achieve as well as the adaptation of drainage on gentle slopes and valleys. The river beds are located within TPI = 1 and by following in this topographic feature continues themselves route. In addition to we will by satellite image analysis on adaptation TPI = 1, on valleys, TPI = 2, on settlements and agricultural areas, TPI = 3, on steep slopes and poor coverage of plant and TPI = 4, on the steep sections and ridgetop.
 

Broken Zagros zone (B)

By analyzing this area to the conclusion that 8.01 % of the zone is valleys, 15.42 % is gentle slope, 66.46 % is steep slope and 10.1 % ridgetop included. By analysis of the drainage network achieve as well as the adaptation of drainage on gentle slopes and valleys. The waterways in the area are located within TPI = 1 and by following in this topographic feature, will be going on. In addition to we will by satellite image analysis and field studies on adaptation of TPI = 1, on valleys, TPI = 2, on residential and agricultural sectors, TPI = 3, the= 3, on steep slopes and sparse vegetation and TPI = 4, the ranges and steep ridge, approved. In this zone the same as the previous zone, b by studying satellite images to overlap TPI = 1, the valleys, TPI = 2, the built-up area ranges and crops, TPI = 3, on steep slopes and low vegetation cover and TPI = 4, the steep and uphill sections.
Conclusion
In this study, the accuracy and TPI model classes, at first with real conditions (field data) and second proportional to the measured resolution of DEM. Select two locations in two construction zones and different morphology and get results of According to environmental conditions is bodes of the reliability of the method used in this research and its applicability. Nevertheless, for analyses was used of models Dickson & Bear (4 classes) in two broken and folded Zagros zones with a further variety of geomorphologic, and a perfect correspondence established values ​​TPI = 1 on valley, TPI = 2, on settlements and agricultural areas, TPI = 3, on steep slopes and low vegetation cover and TPI = 4, on the steep part and ridgetop. In both areas as well as areas with steep slopes where the largest ratio of any Two zones (pilot) is then taken and at the next gentle slopes and ridgetop, and at the finally the valleys lowest area accounted.