Spatial and Temporal Variability of Water Quality for Karun River, in Upstream and Downstream Gotvand Dam

Document Type: Original Article

Authors

Abstract

In this study, the spatial and temporal variability of water quality including monthly series of TDS, EC, So4, Cl, Ca and Na in common statistical period 1993-2014 was evaluated for the Karun River. This assessment is based on qualitative data stations including Susan in the upstream of Gotvand reservoir, Gotvand, Mollasani and Ahvaz in the downstream. To determine the parameters trend process, Mann-Kendall and Sen slope estimator tests were used. Also, Petit test was used to determine the breaking point. The results showed that in all quality parameters of the Susan station, a combination of increasing and decreasing trend is observed. Mainly downward trend is corresponding to the wet months and the upward trend is corresponding to the low water months. Susan, Mollasani and Ahvaz stations are located in downstream of Gotvand dam. The results of modified Mann-Kendall showed clear decrease in water quality after Gotvand dam. The upward trend for the quality parameters were observed in all months of the all stations. According to the results of Sen’s slope estimator, the most trend for the EC series was 108.83 micromhos per centimeter per year, for TDS is 76.07 ppm per year, and for Sulfate, Chlorine ,Calcium and Sodium, are respectively 0.52, 0.65, 0.41 and 0.75 ppm per year. In general it can be found that there are no significant changes in water quality for upstream Gotvand during the study period, however, after the dam, severe changes in water quality parameters have occurred. Based on Petit test, most of changes happened in 2006 and 2007 caused by dam constructing, diversion tunnels and coastal loss in these years. That changes the Karun river water quality in downstream of Gotvand dam. Indeed, water quality Variation before and after the dam construction was showed by hydrometric stations.

دیلم، م. تیموری، م. روحانی، ح. ) 1395 (. روند تغییرات رواناب و کیفیت آب سطحی در رودخانه گرگانرود. نشریه
انجمن آبخیزداری ایران، سال چهارم، شماره 15 ، ص 16 - 11 .
دین پژوه، ی. ) 1395 (. تحلیل روند کیفیت شیمیای آب رودخانه های استان آذربایجان شرقی. نشریه علمی پژوهشی
جغرافیا و برنامه ریزی، سال بیستم، شماره 55 ، ص 124 - 105 .
زارع گاریزی، آ. سعدالدین، ا. بردی شیخ، و. سلمان ماهینی، ع. ) 1391 (. بررسی روند تغییرات بلند مدت متغیرهای
کیفیت آب رودخانه چهلچای )استان گلستان(. مجله پژوهش آب ایران، سال ششم، شماره دهم، ص 165 - 155 .
سلیمانی ساردو، م. ولی، ع. قضاوی، ر و سعیدی، گ. ) 1392 (. آنالیز و روندیابی پارامترهای کیفیت شیمیایی آب.
مطالعه موردی رودخانه چم انجیر خرم آباد، مهندسی آبیاری و آب، شماره دوازدهم، ص 95 - 12 .
موسوی، ر. میرگلوی بیات، ر. معروفی، ص. زارع ابیانه، ح. ) 1388 (. ارزیابی کیفیت آب و تیپ هیدروشیمیایی
رودخانه های نکا، تجن و سفید رود از نظر شرب و کشاورزی. همایش ملی بحران آب در کشاورزی و منابع طبیعی،
شهرری، دانشگاه آزاد شهر ری.
میرعباسی، ر. و دینپژوه، ی ) 1389 (. تحلیل روند تغییرات آبدهی رودخانههای شمالغرب ایران در سه دهه اخیر.
نشریه آب و خاک، شماره بیست و چهارم، ص 768 - 757 .

Anbazhagan, S. and Nair, A. (2004). Geographic information system and ground water quality mapping in Panvel basin, Maharashtra, India. J. Environ. Geol. 45,pp: 753–761.
Antonopoulus, V., Papamichail , D. and Mitsiou, K. (2008).Statistical and trend analysis of water quality and quantity data for the Strymon River in Greece. Hydrology and Earth System Science, 5(4), pp: 679-691.
Boyacioglu, H. (2008). Investigation of Temporal trends in hydro chemical quality of surface water in Western Turkey. Bull Environ Contam Toxicol, 80, pp: 469-474.
Dinpashoh, Y., Mirabbasi, R., Jhajharia, D., Zare Abianeh, H. and A. Mostafaeipour(2014). Effect of Short-Term and Long Term Persistence on Identification of Temporal Trends. Journal of Hydrologic Engineering, 19(3), pp: 617-625.
Hamed, K.H. and Rao, A.R., (1998). A modified Mann Kendall trend test for auto correlated data . Journal of Hydrology, 204, pp: 182–196.
Kauffman, G. J. and Belden, A.C. (2010). Water quality trends (1970 to 2005) along Delaware streams in the Delaware and Chesapeake Bay watersheds, USA. Water Air Soil Pollut, 208, pp:345-375.
Kendall, M.G., (1975). Rank Correlation Measures . Charles Griffin, London .
Kumar, S., Merwade V., Kam, J. and Thurner K. ( 2009). Stream flow trends in Indiana: Effects of long term persistence, precipitation and subsurface drains. Journal of Hydrology, 374(1-2), pp: 171-183.
Mann, H.B. (1945). Non parametric tests against trend. Econometrica, 13, Math Sci Net, pp: 245-259 .
Pettit, A.N. (1979). A non parametric approach to the change-point problem. Applied statistics, 28(2), pp: 126-135.
Yue, S., Pilon, P. and Cavadias, G. (2002). Power of the Mann-Kendall and Spearman's rho tests for detecting monotonic trends in hydrological series. J. Hydrology, 259, pp: 254-271.
Yue, S., and Wang, C.Y., (2003), Applicability of pre whitening to eliminate the influence of serial correlation on the Mann-Kendall test. Water Res., 38 (6), pp: 4-1_4-7.
Yu, Y. S., Zou, S. and Whittemore, D. (1993). Non parametric trend analysis of water quality data of rivers in Kansas . Journal of Hydrology, 150, pp: 61-80.