Suspended Sediment Load Estimation Using Geostatistics Case Study: Talkherood River, Tabriz

Document Type : Original Article

Authors

1 Ph.D. Student, Dept. of Civil Eng., Faculty of Eng., Shiraz University

2 Professor, Dept. of Civil Eng., Faculty of Eng., Shiraz University

3 Assistant Professor, Dept. of Civil Eng., Faculty of Eng., Shiraz University

Abstract

Due to the importance of sediment hydraulics in river engineering and its effects on hydraulics structures, the reliable estimation of the suspended sediment load plays very important role in real and reliable study. Because of some shortages such as technical and economical problems, the data from many sediment-gauging stations in national rivers can not be relied on. Rational data is therefore necessary for some reaches.

In this study, geostatistics and concepts of spatial variables were used in order to find a model for estimation of Talkherood suspended sediment load. For this purpose, a pre-developed software named “Gslib” was used and then estimation of the suspended load of Talkherood River was carried out by both Kriging and Cokriging methods.

In Cokriging method, in addition to suspended load, water discharge is also used as a secondary variable. This variable has a statistical relation with suspended load.

Talkherood River is the most important river in the northern-west of Iran. In this study, the data of 5 hydrographic stations were used for suspended load estimation of Talkherood using both Kriging and Cokriging methods.

For verification of the presented model, cross validation method was used. The result showed that proposed model could be adequately used for estimation of Talkherood suspended load.

Two important points raised from the obtained results are as follows:

Gaussian Variogram model for spatial estimation of Talkherood suspended sediment load has the best fitting on the experimental Variograms and the result of Cokriging method, in which the discharge is used as a secondary and parameter and compared to the Kriging method

Keywords


آوریده، فریبا و بنی حبیب، محمدابراهیم و طاهر شمسی، احمد ،
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