ارزﯾﺎﺑﯽ زﯾﺴﺖ ﻣﺤﯿﻄﯽ آﻟﻮدﮔﯽ ﻓﻠﺰات ﺳﻨﮕﯿﻦ در ﺧﺎكﻫﺎي ﻣﻨﻄﻘﻪ ﺷﻮراب (ﺟﻨﻮب ﮐﺎﺷﻤﺮ- ﺧﺮاﺳﺎن رﺿﻮي)

An Environmental Evaluation of Heavy Metals’ Soil Contamination of Shourab Region (South Kashmar – Khorasan Razavi)

زﻣﯿﻨﻪ و ﻫﺪف: در ﻣﻨﻄﻘﻪ ﺷﻮراب واﻗﻊ در ﺟﻨﻮب ﮐﺎﺷﻤﺮ ﻧﺸﺎﻧﻪﻫﺎﯾﯽ از ذﺧﺎﯾﺮ ﻣﻌﺪﻧﯽ ﺟﯿﻮه، ﺳﺮب، آﻫﻦ و ﻣﺲ ﮔﺰارش ﺷﺪه ﮐﻪ ﻣﯽﺗﻮاﻧﺪ زﻣﯿﻨﻪﺳﺎز آﻟﻮدﮔﯽ زﯾﺴﺖﻣﺤﯿﻄﯽ ﺑﺎﺷﺪ. ﻫﺪف اﯾﻦ ﺗﺤﻘﯿﻖ ﺑﺮرﺳﯽ ﻧﺤﻮه ﺗﻮزﯾﻊ ﻓﻠﺰات ﺳﻨﮕﯿﻦ و ارزﯾﺎﺑﯽ ﻓﺎﮐﺘﻮرﻫﺎي زﻣﯿﻦاﻧﺒﺎﺷﺖ و آﻟﻮدﮔﯽ ﺑﺮاي اﯾﻦ ﻋﻨﺎﺻﺮ در رﺳﻮﺑﺎت رودﺧﺎﻧﻪاي ﻣﻨﻄﻘﻪ ﺷﻮراب ﮐﺎﺷﻤﺮ اﺳﺖ. روش ﺑﺮرﺳﯽ: ﭘﺲ از اﻧﺠﺎم ﻣﻄﺎﻟﻌﺎت ﮐﺘﺎﺑﺨﺎﻧﻪاي و ﭘﺮدازش ﺗﺼﺎوﯾﺮ ﻣﺎﻫﻮارهاي، ﺑﺮرﺳﯽﻫﺎي زﻣﯿﻦﺷﻨﺎﺳﯽ اﻧﺠﺎم ﮔﺮﻓﺖ و ﻧﻬﺎﯾﺘﺎً 21 ﻧﻤﻮﻧﻪ از رﺳﻮﺑﺎت رودﺧﺎﻧﻪاي ﻣﻨﻄﻘﻪ ﺑﺮداﺷﺖ ﮔﺮدﯾﺪ. ﭘﺲ از ﺗﻌﯿﯿﻦ ﺑﺎﻓﺖ ﺧﺎك و ﭘﺎراﻣﺘﺮﻫﺎي ﺷﻮري، EC ،pH، 14 ﻧﻤﻮﻧﻪ ﺑﺮاي ﺑﺮرﺳﯽ ﻏﻠﻈﺖ ﻓﻠﺰات ﺳﻨﮕﯿﻦ ﺗﻮﺳﻂ دﺳﺘﮕﺎه ICP-OS در آزﻣﺎﯾﺸﮕﺎه زرآزﻣﺎ آزﻣﺎﯾﺶ ﺷﺪ. ﻧﺘﺎﯾﺞ ﺑﻪدﺳﺖ آﻣﺪه ﺗﻮﺳﻂ ﻧﺮماﻓﺰارﻫﺎي GIS , Excel ,SPSS ﭘﺮدازش و ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺖ. ﯾﺎﻓﺘﻪﻫﺎ: ﺑﻪ اﺳﺘﺜﻨﺎي ﻋﻨﺎﺻﺮ ﻧﻘﺮه، ﻣﺲ، ﮐﺎدﻣﯿﻮم، ﮐﺒﺎﻟﺖ، ﮐﺮوم و ﻧﯿﮑﻞ ﮐﻪ ﺗﺎ ﺣﺪي آﻟﻮدﮔﯽ ﻧﺸﺎن ﻣﯽدﻫﻨﺪ، ﺑﻘﯿﻪ ﻋﻨﺎﺻﺮ در ﻣﻨﻄﻘﻪ ﺑﻪﻃﻮر ﺟﺪي ﻧﻘﺶ آﻟﻮده ﮐﻨﻨﺪهاي ﻧﺪارﻧﺪ. ﻣﯿﺰان pH از 7/5 ﺗﺎ 8/2 و ﻣﯿﺰان EC از 3 ﺗﺎ 5 µs/cm و ﺷﻮري 150 ﺗﺎ 2500 ﻣﺘﻨﺎﺳﺐ ﺑﺎ ﻫﺪاﯾﺖ اﻟﮑﺘﺮﯾﮑﯽ ﻣﺘﻐﯿﺮ اﺳﺖ. ﺑﺤﺚ و ﻧﺘﯿﺠﻪﮔﯿﺮي: اﻟﮕﻮي ﭘﺮاﮐﻨﺪﮔﯽ ﻋﻨﺎﺻﺮ ﻧﯿﮑﻞ و ﮐﺒﺎﻟﺖ و ﺗﺎ ﺣﺪودي ﮐﺮوم در رﺳﻮﺑﺎت رودﺧﺎﻧﻪاي ﻣﻨﻄﻘﻪ اﻧﻄﺒﺎق ﻣﻌﯿﻨﯽ ﺑﺎ ﯾﮑﺪﯾﮕﺮ ﻧﺸﺎن ﻣﯽدﻫﻨﺪ. اﯾﻦ اﻣﺮ ﻣﯽﺗﻮاﻧﺪ ﺑﺎ ﺗﺮﮐﯿﺐ ﺳﻨﮓﺷﻨﺎﺳﯽ ﺑﺎﻻدﺳﺖ آﺑﺮاﻫﻪﻫﺎ ﮐﻪ ﻋﻤﺪﺗﺎً ﺳﻨﮓﻫﺎي وﻟﮑﺎﻧﯿﮑﯽ آﻧﺪزﯾﺘﯽ ﻫﺴﺘﻨﺪ، ﻣﺮﺗﺒﻂ ﺑﺎﺷﺪ. ﻋﻨﺎﺻﺮ ﺳﺮب و روي ﻋﻤﺪﺗﺎً در آﺑﺮاﻫﻪﻫﺎ و رﺳﻮﺑﺎت ﺑﺨﺶﻫﺎي ﺷﻤﺎﻟﯽ و ﺷﺮﻗﯽ ﻣﻨﻄﻘﻪ و ﻋﻨﺎﺻﺮ آرﺳﻨﯿﮏ و آﻧﺘﯿﻤﻮان ﻧﯿﺰ در رﺳﻮﺑﺎت ﺷﻤﺎل و ﺷﻤﺎل ﻏﺮﺑﯽ ﺗﻤﺮﮐﺰ ﺑﯿﺸﺘﺮي ﻧﺸﺎن ﻣﯽدﻫﻨﺪ. اﯾﻦ اﻣﺮ ﻣﻤﮑﻦ اﺳﺖ ﻣﺮﺗﺒﻂ ﺑﺎ ﮐﺎﻧﯽﺳﺎزيﻫﺎي اﯾﻦ ﻧﻮاﺣﯽ ﺑﺎﺷﺪ ﮐﻪ ﺗﺎﮐﻨﻮن ﻣﻮرد ﺗﻮﺟﻪ ﻗﺮار نگرفته است

Background and Objective: The purpose of this research is to investigate the distribution of heavy metals and evaluating geo-accumulation and contamination factors on these elements in the stream sediments of Shourab Kashmar area. There are indications of some elements such as Mercury, Lead, Iron, and Copper that might be the cause for environmental pollution in this area. Method: After processing of satellite images and performing geological studies, 21 samples of stream sediments were gathered. By determining the salinity, pH, and EC parameters as well as the soil texture of samples, 14 samples were tested in order to study the concentration of heavy metals with the ICP-OS systems in the ZarAzma Laboratory. The collected results were processed and studied using GIS, SPSS, and Excel software. Findings: With the exception of the Silver, Copper, Cadmium, Cobalt, Chromium, and Nickel elements which show some level of contamination, there is no evidence of environmental pollution, in the stream sediments in this area. The amount of pH from 7.5 to 8.2 and EC from 0.3 μs/cm to 5 μs/cm and salinity from 150 to 2500 are varying. Discussion and Conclusion: There is a similarity between the distribution of the Nickel, Cobalt, and to some degrees, Chromium in the stream sediments of the study area. This can be related to the volcanic rocks which are mainly intermediate in composition. The Lead and Zinc are mainly concentrated on the north and some towards east of the area, and the Arsenic and Antimony elements in the north and north-west of the study area. The origin of these elements could be connected to mineralization in this area, which has not been focused on so far.