بررسی وضعیت عناصر سنگین در خاک‌های ایران: مروری جامع و انتقادی بر مطالعات گزارش شده

نوع مقاله : مروری

نویسندگان

1 موسسه تحقیقات خاک و آب، ﺳﺎزﻣﺎن ﺗﺤﻘﯿﻘﺎت، آﻣﻮزش و ﺗﺮوﯾﺞ ﮐﺸﺎورزی، ﮐﺮج، اﯾﺮان

2 گروه علوم و مهندسی خاک، دانشکده مهندسی و فناوری کشاورزی دانشگاه تهران، کرج، ایران

10.22059/ijswr.2022.341586.669245

چکیده

در دنیا توجه به غلظت فلزات سنگین در خاک بدلیل خطرات بالقوه آن‌ها برای محیط زیست و سلامت انسان افزایش یافته است. در چند دهه اخیر، مطالعات زیادی بر روی آلودگی خاک‌ها توسط فلزات سنگین در ایران صورت گرفته است ولی اکثر مطالعات، وضعیت غلظت فلزات سنگین خاک را در مقیاس ملی نشان نمی‌دهد. از طرف دیگر باوجود اهمیت غلظت زمینه برای ارزیابی آلایندگی و خطر زیست محیطی این فلزات، هنوز مطالعه‌ای در مورد آن برای خاک‌های ایران در سطح ملی منتشر نشده است. در این پژوهش تلاش شد تا بر اساس تجزیه و تحلیل کمی و کیفی نتایج مطالعات گزارش شده شناخت جامعی از وضعیت عناصر سنگین در خاک‌های ایران در مقیاس ملی ارائه شود. برای انجام این پژوهش در مجموع 247 مطالعه (مقاله و گزارش نهایی طرح‌های تحقیقاتی) در زمینه پایش میدانی عناصر سنگین در خاک‌های ایران که تا آبان 1400 منتشر شده بودند جمع‌آوری گردید. اطلاعات مورد نیاز (نتایج تجزیه حدود 21400 نمونه خاک) از مطالعات استخراج و ابتدا از نظر شاخص‌های تضمین و کنترل کیفیت تجزیه ارزیابی شدند. سپس مطالعات بر اساس نوع کاربری به کشاورزی، شهری و صنعتی تفکیک و پس از غربال و انتخاب مطالعاتی که دارای حداقل‌های لازم از نظر کنترل کیفی بودند، آماره‌های مختلف از جمله میانگین وزنی، میانه، غلظت زمینه و شاخص آلودگی عناصر سنگین (As، Pb، Cd، Cr، Co، Ni، Cu و Zn) محاسبه و تجزیه و تحلیل شدند....

کلیدواژه‌ها


عنوان مقاله [English]

Investigation of the status of heavy metals in soils of Iran: A comprehensive and critical review of reported studies

نویسندگان [English]

  • Karim Shahbazi 1
  • Arzhang Fathi-Gerdelidani 2
  • Mostafa Marzi 1
1 Professor, Soil and Water Research Institute, AREEO, Karaj, Iran
2 Department of Soil Science, Faculty of Agricultural Engineering and Technology, University of Tehran, Iran
چکیده [English]

In the world, attention to the content of heavy metals in the soil has increased due to their potential risks to the environment and human health. In recent decades, many studies have been reported on soil contamination by heavy metals in Iran, but most studies do not show heavy metal status in soils on a national scale. On the other hand, despite the importance of background concentration of heavy metals for the assessment of pollution and environmental risks of these metals, no study has yet been published for soils of Iran at the national scale. In this study, an attempt was made to provide a comprehensive understanding of the status of heavy metals in soils of Iran on a national scale based on quantitative and qualitative analysis of the results of studies reported. To conduct this research, a total of 247 studies (both articles and final reports of research projects on field monitoring of heavy metals in soils of Iran that were published until November 2021 were collected. The required information (analysis results of about 21,400 soil samples) were extracted from the studies and first evaluated in terms of quality assurance and quality control criteria. Then, studies were classified into agricultural, urban and industrial based on the type of land use, and after screening and selecting studies that had the minimums required in terms of quality control, various statistics such as weighted average, median, background concentration and pollution index for heavy metals As, Pb, Cd, Cr, Co, Ni, Cu and Zn were calculated and analyzed....

کلیدواژه‌ها [English]

  • Agricultural
  • urban and industrial soils
  • Background concentration
  • Potentially toxic elements
  • Quality control
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