Document Type : Research Paper

Author

Member of the Faculty, Azad Islamic University of Semnan

Abstract

By expanding the application of the Global Positioning System (GPS), this method became increasingly inexpensive, light and easy. The accuracy of the GPS was improved, and apparently, the constant control of the morphological changes on the surface of the earth altered slowly and modestly. The purpose of the study is to measure morphology of ditches in a pond near Loyd in the Shankxi province using GPS. there are three main types of ditches within the area of study: the side ditches, valley ditches, hill slope ditches. This research focuses mainly on ditches of the hill slopes. The ditches of the slope in the research area are largely discontinuous and develop rapidly. In the area of ​​research, the density of the ditch is very large. The regress rate of the slopes of the hill is 0.16-2.0m per year. The relationship between the drainage area with high slope (A) and the main slope (S) of the ditches of hill slopes is S = 0.1839 A. The 2AS values ​​in the main cuttings of the hill slope ditches are in a range of 41 to 814 square meters and most of them range from 100 to 300 square meters. Both of these relationships are considered as indicators of the position of the ditch’s main cutting.

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