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National data from the hydrological network for 38 rivers out of 25 watersheds were used to detect spatial and temporal trends in water quality and quantity characteristics between 1995 and 2002. Assessment of water quality and quantity included flow rate, water temperature, pH, electrical conductivity, sodium adsorption rate, Na, K, Ca+Mg, CO3, HCO3, Cl, SO4, and boron. Among the major ions assessed on a watershed basis, Turkish river waters are relatively high in Ca+Mg, Na and HCO3, and low in K and CO3. The watersheds in Turkey experienced a general trend of 16% decrease in flow rates between 1995 and 2002 at a mean annual rate of about 4 m3 s?1, with a considerable spatial variation. Similarly, there appeared to be an increasing trend in river water temperature, at a mean annual rate of about 0.2°C. A substantial proportion of watersheds experienced an increase in pH, in particular, after 1997, with a maximum increase from 8.1 to 8.4 observed in Euphrates (P?0.01). Kendall’s tau test revealed increasing trends of EC and SAR concentrations that exceeded existing standards, particularly, in the Meriç, K?z?l?rmak and Big Menderes watersheds where intensive agricultural activities take place. Such continued levels may threaten biotic integrity and both drinking and irrigation water quality of rivers. Best multiple linear regression (MLR) models constructed both annually and monthly differed in R 2 values in accounting for variations of pH and water temperature only. The findings of the study can provide a useful assessment of controls over water quality and quantity and assist in devising integrated and sustainable management practices for watersheds at the regional scale in Turkey. 相似文献
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Tureyen Oktay E. Yilmaz Atilla Yakan Sevil D. Yetiskin Berkant Okay Oguz Okay Oya S. 《Environmental science and pollution research international》2021,28(4):3766-3773
Environmental Science and Pollution Research - In this study, two macroporous butyl rubber (BR)–based sorbents prepared in benzene (H-BR) and in cyclohexane (L-BR) with different porosities... 相似文献
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Spatial and seasonal differences in water quality of drainage water and unconfined shallow groundwater were related to irrigation in Samandağ, a Mediterranean coastal region. Eighteen wells, seven drainage points and Orontes River were monitored bimonthly for one year for analyses of electrical conductivity (EC), total dissolved solids (TDS), sodium adsorption ratio (SAR), cations (Na, K, Ca + Mg) and anions (CO3, HCO3, Cl and SO4). Agricultural irrigation using saline groundwater decreased water quality of Orontes River during the irrigation season (May to September) more than during the non-irrigation season (October to April). Seasonal fluctuations in water quality of shallow groundwater were greater during the irrigation season than the non-irrigation season in the study area. Excessive use of groundwater resulted in a decline in the water table levels in the irrigation season. Water table level rose up to the soil surface in areas where there was a lack of drainage or poor drainage, due to the impact of precipitation in the winter. SAR and pH values of drainage water increased in the irrigation season, while the other properties of drainage water decreased. Irrigation water quality of Orontes River was classified as C3S1 in both seasons. Irrigation water quality of shallow groundwater and drainage water varied from C2S1 to C4S2 in one year. Drainage and well waters were found to be different on yearly basis in terms of Na, SAR (p<0.01) and Ca + Mg concentrations (p<0.001). Ca + Mg concentrations for both sources were different for all sampling dates (p<0.001). 相似文献
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Berkant Odemis Mustafa Kemal Sangun Fatih Evrendilek 《Environmental monitoring and assessment》2010,170(1-4):475-490
The Euphrates and Tigris watersheds originating from Turkey and passing through Syria and Iraq are one of the most important transboundary watersheds in the Middle East. Long-term data (1971 to 2002) from 14 stations over the Euphrates river and seven stations over the Tigris river were analyzed and compared using the nonparametric Kruskal–Wallis and Mann–Kendall trend tests, and box-and-whisker plots. The upper Euphrates river had significantly lower values of flow rate (FR), water temperature (WT), electrical conductivity (EC), Cl, and SO4 than did the lower Euphrates river. The middle Euphrates river had significantly higher Na, K, HCO3, Cl, sodium adsorption ratio (SAR), and boron (B) and lower EC and SO4 than the lower Euphrates river. The upper west Tigris river had higher EC, Ca + Mg, and SO4 and lower FR, Na, and SAR than the lower Tigris river. The upper east Tigris river had higher HCO3 and B and lower FR and WT than the lower Tigris river. 相似文献
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