كليدواژه :
فلزات سنگين , شاخص فلزي , شرب , رامسر , چشمه
چكيده فارسي :
منطقه‌ي مورد مطالعه در غربي‌ترين بخش استان مازندران و در حوالي شهرستان رامسر واقع شده است. هدف از اين تحقيق تشخيص خصوصيات هيدروژئوشيميائي و تعيين كيفيت آب‌هاي 5 چشمه منتخب در حوالي شهرستان رامسر جهت شرب است. در اين پژوهش نمونه‌ها از لحاظ پارامترهاي فيزيكي و شيميايي نظيرTDS ، Ec، Eh، pH، آنيون‌هاي اصلي و كاتيون‌ها و بعضي از عناصر كمياب مورد ارزيابي قرار گرفتند. داده‌هاي حاصله توسط نرم افزار AqQA پردازش و نمودارهاي مربوطه رسم شدند. پارامترهاي فيزيكوشيميايي چشمه‌ها با يكديگر و نيز با استانداردهاي WHO، ايران (1053)، شولر و سازمان حفاظت محيط زيست آمريكا (US.EPA) مقايسه شدند. با استفاده از شاخص‌هاي مختلف نمونه‌ها مورد ارزيابي كيفي قرار گرفتند. چشمه كچانك از نوع (Si-HCO3) است در حالي كه چشمه‌هاي كتالم، ريش‌برازدره، نمكدره و گياش از نوع (Si-Cl) مي‌باشد. مقايسه چشمه‌ها نشان مي‌دهد كه مقدار شاخص فلزي (MI) و غلظت عناصر سنگين مثل نيكل، آرسنيك، سرب و كروم در چشمه كتالم نسبت به بقيه بالاتر است. هرچند كه جهت شرب بعضي از چشمه‌ها از لحاظ منيزيم، كلسيم و pH در بازه مطلوب قرار نمي‌گيرند ولي تمامي چشمه‌هاي منطقه مورد مطالعه از لحاظ بقيه پارامترها در گروه خوب يا قابل قبول قرار دارند.
چكيده لاتين :
1-Introduction
The studied area is located in the westernmost part of Mazandaran province around Ramsar city and is part of the southern coast of the Caspian Sea. Elika, Nesen, Ruteh, Mobarak, Dorood, and Javaherdeh formation are exposed (Baharfiroozi et al., 2000). The general strike of geological structures of the area is northwest-southeast and dominated by abundant faults (Alavi, 1996). Studied springs of this area are including Kachanak, Katalom, Rishboraz Darreh, Namak Darreh, and Giash. Kachanak and Katalom springs are located in the plain areas, and Rishboraz Darreh, Namak Darreh, and Giash are in highlands of Ramsar city.
Hydrogeologically, the aquifer of the study area is unconfined, and its hydraulic gradient is toward the sea. In this research, the quality of water of springs has been considered because it represents not only the quality of underground water but also the people of the area drinks it, and it can affect the native’s health. So, the aim of this research is the specification of the hydrogeochemical properties and define the water quality of 5 selected springs around the Ramsar city for drinking.
2-Methodology
The springs were sampled according to the required standards using polyethylene bottles in the last days of summer. Dual-purpose conductor and acidity measured electrical conductivity, and total dissolved solids were measured by pH meter. BOD was estimated in five days using incubator (equipped with oxygen meter sensor) in 200C temperature. The alkalinity and chloride contents were measured through titration. Alkalinity was obtained by addition of Phenolphthalein and Methyl Orange to the samples and performing titration until reaching the final point (orange-pink color) and presented in milligram per liter of calcium carbonate. Bicarbonate also was measured by using calcium carbonate contents and applying related coefficients. Potassium chromate was used as a marker for measuring centration of chloride contents in the titration process. Nitrate and sulfate were evaluated using ultraviolet (UV) and spectrophotometry methods, respectively. Major and trace elements concentration obtained through inductively coupled plasma mass spectrometry (ICP-MS) in the laboratory of Act Labs Company in Canada. Hydrogeochemical processing of the samples was done by AqQa software.
3-Findings
Data processing results indicated that except Kachanak spring (which is of Si-HCO3 type), all the springs are of Si-Cl water type (table 1). The plot of hydrogeochemical data of the studied springs on the Piper diagrams suggested that alkaline earth metals (Ca+, Mg2+) are more than alkaline elements (K+, Na+) and anions of strong acids (SO2-4) are more than weak acids ones (HCO-3), and noncarbonate hardness is over 50%. Water quality also considered through comparing of physicochemical parameters of the springs with different standards (Table 1).
Table 1- Correlation the physiochemical parameters of the springs with different standards.
