Abstract
Measurements of suspended sediments in rivers are important for understanding soil losses, controlling waterpollution, planning and management of water storage structures,. Due to temporal and spatial variation, measurement of suspendedsediments is very difficult. The traditional technique for measuring concentration is direct water sampling method which has manysampling and laboratory difficulties. However, this technique is restrictive in its ability to provide continuous monitoring ofsuspended sediment concentration. Turbidity measurement is an alternative indirect method to determined sediment concentration.Changes in turbidity values depending on particles in water, sediment concentration can be estimated. This method is relativelycheap and easy, and it supply continuous monitoring with suitable calibrations. But it can be considered of particles and waterproperties effect on turbidity. This problem can be solved with more frequently calibration or definition of effective factors. In thisstudy particles size affecting on turbidity values was investigated with using four different sediment sizes (0-50, 50-100, 100-200and 200-250 micron)The highest turbidity values were determined for small size sediment and it decreased for bigger sediment size. Clay contentdecreased of relationship between sediment and turbidity and caused reading error for high concentration (> 4 g L). However Rvalues were obtained bigger than 0.90 for all treatments. As a result of this study it could be concluded that this method can beused for sediment concentration measurement with adequately accuracy besides cheap and easy using advantages.
Keywords
References
- APHA, 1999. Standard Methods for the Examination of Water and Wastewater. 20th edn. American Public Health Association,Washington, D.C.
- Chanson, H., Takeuchi, M., Trevethan, M., 2008. Using turbidity and acoustic backscatter intensity as surrogate measures of suspended sediment concentration in a small subtropical estuary. J. Environ. Manage. 88, 1406-1416.
- Foster, I .D. L., Millington, R., Grew, R. G., 1992. The impact of particle size controls on stream turbidity measurement; some implications for suspended sediment yield estimation. Erosion and sediment transport monitoring programmes in river basins. Proceedings of a Workshop, Oslo, IAHS-AISH Publ. no. 210, pp 51–62.
- Gippel, C.J., 1989. The Use of Turbidity Instruments to Measure Stream Water Suspended Sediments Concentration. Department of Geography and Oceanography. University College, Australian Defense Force Academy. Monograph Series No. 4.
- Gray, J. R., Glysson, G. D., Mueller, D. S., 2002. Comparability and accuracy of fluvial-sediment data-a view from the US Geological Survey. Proceedings of the American Society of Civil Engineers Hydraulics Measurements & Experimental Methods Symposium, Estes Park, CO, July 28 –August 1. Nakato, T., 1988. Test of selected sediment transport formulas. J. Hydraul. Eng. 116, 362-379.
- McBean, E. A., Al-Nassri, S., 1988. Uncertainty in suspended sediment transport curves. J. Hydraul. Eng. 114, 63-73.
- Mitchell, S. B., Lawler, D. M., West, J. R., Couperthwaite, J. S., 200 Use of continuous turbidity sensor in the prediction of fine sediment transport in the turbidity maximum of the trent Estuary. UK. Coastal and Shelf Sci. 58, 645–652. Pavanelli, D., Bigi, A., 2005. Indirect analysis methods to estimate suspended sediment concentration: reliability and relationship of turbidity and settleable solids. Biosystems Eng. 90, 75–83.
- Sun, H., Cornish, P. S., Daniell, T. M., 2001. Turbidity based erosion estimation in catchment in South Australia. J. Hydrol. 253, 227-238.
- Yalçın, E., Uludağ, S., Düz, M., 2006. Türkiye Akarsularında Süspanse Sediment Gözlemleri (1999-2005). Hidrolik Etütler Dairesi Başkanlığı Yayınları, 978-975-8964-69-7. Ziegler, C. A., 2002. Issues related to use of turbidity measurements surrogate for suspended sediment. Turbidity and Other Sediment Surrogates Workshop, April 30 – May 2, Reno, NV.
Abstract
ÖZET : Akarsularda sediment ölçümü erozyonla kaybolan toprak miktarının tahmininde, su kirliliğinin kontrol edilmesinde, su depolama yapılarının planlanması ve yönetiminde büyük önem taşımaktadır. Ancak sediment taşınımının alan ve zamansal bazlı çok değişken olması nedeniyle yeterli doğrulukta ölçülmesi oldukça zordur. Geleneksel sediment ölçümlerinde örnekleme ve laboratuvar işlemleri pek çok zorluklar içermekle birlikte ölçümlerde sürekliliği de sağlayamamaktadır. Alternatif bir yöntem olarak bulanık değerleri ile dolaylı olarak sediment değerleri tahmin edilebilmektedir. Bulanıklığın su içerisindeki parçacıkların ışığı yansıtmasına bağlı olarak değişmesinden hareketle konsantrasyon hakkında gerçekçi tahminler elde edilmektedir. Nispeten ucuz ve kullanımı kolay olay bu yöntem uygun kalibre koşullarında kullanıldığında sedimentin sürekli izlenmesine olanak sağlayabilecek niteliktedir. Burada önemli olan nokta, sedimentin özelikleri ve su kalitesine bağlı olarak bulanıklık değerlerinin farklı şekillerde etkilenmesidir. Bu problemin doğrudan örnekleme yöntemiyle daha sık kalibre kontrollerinin yapılmasıyla veya debi, su kalitesi ve sediment tane özellikleri gibi etkenlerin tanımlanmasıyla elimine edilebileceği düşünülmektedir. Bu amaç gözetilerek bu çalışmada sediment tane çap değişiminin bulanıklık değerlerine etkisi ve sediment konsantrasyon ilişkileri incelenmiştir. Bu amaçla 0-50, 50-100, 100-200 ve 200-250 mikron aralıklarında dört farklı sediment materyali için bulanıklık ölçümleri yapılmıştır. Dane çapı en düşük olan ortamda en yüksek bulanıklık değerleri elde edilirken dane çapının artmasına bağlı bulanıklık değerleri de düşmüştür. Bu durum kil içeriği daha yüksek örneklerde sediment bulanıklık ilişkisini düşürürken, yüksek konsantrasyon (> 4 g L-1) değerlerinde bulanıklık ölçümlerinin hata verdiği görülmüştür. Bununla beraber bulanıklık - konsantrasyon arasındaki R2 değerleri tüm konularda 0.90’ın üzerinde bulunmuştur. Sonuç olarak bulanıklık ölçümü, ucuz ve kullanım kolaylığı yanı sıra, yeterli doğrulukta ve sürekli sediment izleme amaçlı kullanılabileceği anlaşılmıştır.
Anahtar Kelimeler: Sediment, Bulanıklık, Su kirliliği.
Assessment of Turbidity-Concentration Relations in Different Sediment Sizes
ABSTRACT : Measurements of suspended sediments in rivers are important for understanding soil losses, controlling water pollution, planning and management of water storage structures,. Due to temporal and spatial variation, measurement of suspended sediments is very difficult. The traditional technique for measuring concentration is direct water sampling method which has many sampling and laboratory difficulties. However, this technique is restrictive in its ability to provide continuous monitoring of suspended sediment concentration. Turbidity measurement is an alternative indirect method to determined sediment concentration. Changes in turbidity values depending on particles in water, sediment concentration can be estimated. This method is relatively cheap and easy, and it supply continuous monitoring with suitable calibrations. But it can be considered of particles and water properties effect on turbidity. This problem can be solved with more frequently calibration or definition of effective factors. In this study particles size affecting on turbidity values was investigated with using four different sediment sizes (0-50, 50-100, 100-200 and 200-250 micron)
The highest turbidity values were determined for small size sediment and it decreased for bigger sediment size. Clay content decreased of relationship between sediment and turbidity and caused reading error for high concentration (> 4 g L-1). However R2 values were obtained bigger than 0.90 for all treatments. As a result of this study it could be concluded that this method can be used for sediment concentration measurement with adequately accuracy besides cheap and easy using advantages.
Keywords: Sediment, Turbidity, Water pollution
Keywords
References
- APHA, 1999. Standard Methods for the Examination of Water and Wastewater. 20th edn. American Public Health Association,Washington, D.C.
- Chanson, H., Takeuchi, M., Trevethan, M., 2008. Using turbidity and acoustic backscatter intensity as surrogate measures of suspended sediment concentration in a small subtropical estuary. J. Environ. Manage. 88, 1406-1416.
- Foster, I .D. L., Millington, R., Grew, R. G., 1992. The impact of particle size controls on stream turbidity measurement; some implications for suspended sediment yield estimation. Erosion and sediment transport monitoring programmes in river basins. Proceedings of a Workshop, Oslo, IAHS-AISH Publ. no. 210, pp 51–62.
- Gippel, C.J., 1989. The Use of Turbidity Instruments to Measure Stream Water Suspended Sediments Concentration. Department of Geography and Oceanography. University College, Australian Defense Force Academy. Monograph Series No. 4.
- Gray, J. R., Glysson, G. D., Mueller, D. S., 2002. Comparability and accuracy of fluvial-sediment data-a view from the US Geological Survey. Proceedings of the American Society of Civil Engineers Hydraulics Measurements & Experimental Methods Symposium, Estes Park, CO, July 28 –August 1. Nakato, T., 1988. Test of selected sediment transport formulas. J. Hydraul. Eng. 116, 362-379.
- McBean, E. A., Al-Nassri, S., 1988. Uncertainty in suspended sediment transport curves. J. Hydraul. Eng. 114, 63-73.
- Mitchell, S. B., Lawler, D. M., West, J. R., Couperthwaite, J. S., 200 Use of continuous turbidity sensor in the prediction of fine sediment transport in the turbidity maximum of the trent Estuary. UK. Coastal and Shelf Sci. 58, 645–652. Pavanelli, D., Bigi, A., 2005. Indirect analysis methods to estimate suspended sediment concentration: reliability and relationship of turbidity and settleable solids. Biosystems Eng. 90, 75–83.
- Sun, H., Cornish, P. S., Daniell, T. M., 2001. Turbidity based erosion estimation in catchment in South Australia. J. Hydrol. 253, 227-238.
- Yalçın, E., Uludağ, S., Düz, M., 2006. Türkiye Akarsularında Süspanse Sediment Gözlemleri (1999-2005). Hidrolik Etütler Dairesi Başkanlığı Yayınları, 978-975-8964-69-7. Ziegler, C. A., 2002. Issues related to use of turbidity measurements surrogate for suspended sediment. Turbidity and Other Sediment Surrogates Workshop, April 30 – May 2, Reno, NV.
Details
| Primary Language | tr;en |
|---|---|
| Journal Section | ARAŞTIRMALAR |
| Authors | |
| Publication Date | May 27, 2014 |
| Published in Issue | Year 2013 Volume: 44 Issue: 1 |
Cite
Articles published in this journal are published under the Creative Commons International License (https://creativecommons.org/licenses/by-nc/4.0/). This allows the work to be copied and distributed in any medium or format provided that the original article is appropriately cited. However, the articles work cannot be used for commercial purposes.
https://creativecommons.org/licenses/by-nc/4.0/