ORIGINAL RESEARCH
Determination of Temporal Changes
in the Sinuosity and Braiding Characteristics
of the Kizilirmak River, Turkey
Derya Ozturk, Faik Ahmet Sesli
More details
Hide details
Department of Geomatics Engineering, Ondokuz Mayis University, 55139 Samsun, Turkey
Submission date: 2015-06-02
Final revision date: 2015-06-24
Acceptance date: 2015-07-06
Publication date: 2015-09-21
Pol. J. Environ. Stud. 2015;24(5):2095-2112
KEYWORDS
TOPICS
ABSTRACT
In this study, the pattern of the approximately 1,300-km-long Kizilirmak River was recreated in a geographic
information system (GIS) environment using data obtained from Landsat TM/ETM+/OLI satellite
images from 1987, 2000, and 2013. The temporal changes in the sinuosity and braiding characteristics of the
river were determined for the periods 1987-2000 and 2000-13. The right and left shorelines of the Kizilirmak
River and the shorelines of islands and bars within the river channel were extracted automatically from the
satellite images by integrating the normalized difference water index (NDWI) and modified normalized difference
water index (MNDWI). The data required for measuring the sinuosity and braiding characteristics
were obtained by evaluating the shorelines in the GIS environment. The braiding index (BI), braid-channel
ratio (B), and braiding ratio (BR) were used to determine the braiding of the river, and the sinuosity index was
used to determine the sinuosity of the river. The Kizilirmak River was divided into 21 analyzed sections based
on the locations of dams. The sinuosity decreased in 15 sections in 1987-2000 and 2000-13. The BI, B, and
BR values decreased in 11 sections in 1987-2000 and in 9 sections in 2000-13. Sinuosity and braiding both
decreased in most of the sections downstream of dams; these sections were often subject to uncontrolled sand
and gravel extractions.