بررسي ميزان تجمع سرب و كادميوم در بافت سخت خرچنگ‌ منزوي (scaevola Coenobita) و رسوبات جزيره كيش

The Concentration of Lead and Cadmium in the Hermit Crab (Coenobita scaevola) and Sediments of KISH Island

زﻣﯿﻨﻪ و اﻫﺪاف: ﺣﻀﻮر ﺧﺮﭼﻨﮓﻫﺎي ﻣﻨﺰوي در زﻧﺠﯿﺮه ﻏﺬاﯾﯽ آﺑﺰﯾﺎن و ﭘﺮﻧﺪﮔﺎن ﺳﺎﺣﻠﯽ و ﻧﻘﺶ ﻗﺎﺑﻞ ﺗﻮﺟﻪ در ﭘﺎكﺳـﺎزي ﻣﺤـﯿﻂ ﻧﺸـﺎن دﻫﻨﺪهي اﻫﻤﯿﺖ ﻣﻄﺎﻟﻌﻪ اﯾﻦ ﮔﻮﻧﻪﻫﺎ ﺑﻪ ﻋﻨﻮان ﺷﻨﺎﺳﺎﮔﺮﻫﺎي زﯾﺴﺘﯽ اﺳﺖ. از اﯾﻦ رو ﻣﻄﺎﻟﻌﻪ ﺣﺎﺿﺮ ﺑﻪ ﺗﻌﯿﯿﻦ ﻣﯿﺰان ﻏﻠﻈﺖ ﺳـﺮب و ﮐـﺎدﻣﯿﻮم در رﺳﻮﺑﺎت و ﺑﺎﻓﺖ ﺳﺨﺖ ﺧﺮﭼﻨﮓ ﻣﻨﺰوي در ﺳﻮاﺣﻞ ﺟﺰﯾﺮه ﮐﯿﺶ و ﻣﻘﺎﯾﺴﻪ آن ﺑﺎ اﺳﺘﺎﻧﺪاردﻫﺎي ﺟﻬﺎﻧﯽ ﭘﺮداﺧﺘﻪ اﺳﺖ. روش ﺑﺮرﺳﯽ: ﺑﺮاي ﺗﻌﯿﯿﻦ ﻏﻠﻈﺖ ﺳﺮب و ﮐﺎدﻣﯿﻮم، اﺑﺘﺪا ﺑﺎ اﺳﺘﻔﺎده از ﻃﺮح ﻧﻤﻮﻧﻪﺑﺮداري ﺗﺼـﺎدﻓﯽ، ﺗﻌـﺪاد 30 ﻧﻤﻮﻧـﻪ رﺳـﻮب و 60 ﻧﻤﻮﻧـﻪ ﺧﺮﭼﻨﮓ از ﺟﻨﻮب و ﺟﻨﻮب ﺷﺮق ﺟﺰﯾﺮه ﮐﯿﺶ در ﺳﺎل 1395ﺑﺮداﺷﺖ ﮔﺮدﯾﺪ. ﺳﭙﺲ ﻏﻠﻈﺖ ﺳﺮب و ﮐﺎدﻣﯿﻮم ﻣﻮﺟـﻮد در ﺑﺎﻓـﺖ ﺳـﺨﺖ ﻫـﺮ ﻧﻤﻮﻧﻪ ﺑﺎﻓﺖ و رﺳﻮب ﺑﺎ اﺳﺘﻔﺎده از دﺳﺘﮕﺎه اﺳﭙﮑﺘﺮوﻓﺘﻮﻣﺘﺮي ﺟﺬب اﺗﻤﯽ اﻧﺪازهﮔﯿﺮي و ﺑﺎ ﺣﺪود اﺳﺘﺎﻧﺪارد ﻣﻘﺎﯾﺴﻪ ﺷﺪ. ﯾﺎﻓﺘﻪﻫﺎ: ﻣﯿﺎﻧﮕﯿﻦ ﺳﺮب و ﮐﺎدﻣﯿﻮم در رﺳﻮﺑﺎت ﺳﻮاﺣﻞ ﺟﻨﻮب و ﺟﻨﻮب ﺷﺮق ﺟﺰﯾﺮه ﮐﯿﺶ ﺑﻪ ﺗﺮﺗﯿﺐ 63/20 و 2/94 ﻣﯿﻠﯽ ﮔﺮم ﺑﺮ ﮐﯿﻠـﻮﮔﺮم ﺑﻪ دﺳﺖ آﻣﺪ ﮐﻪ ﻫﺮ دو از اﺳﺘﺎﻧﺪاردﻫﺎي ﮐﯿﻔﯿﺖ رﺳﻮب ﮐﺎﻧﺎدا و آﻣﺮﯾﮑﺎ ﺑﺎﻻﺗﺮ اﺳﺖ. ﻣﯿﺎﻧﮕﯿﻦ ﺳﺮب و ﮐﺎدﻣﯿﻮم در ﺑﺎﻓﺖ ﺳﺨﺖ ﻧﻤﻮﻧﻪ ﻫﺎي ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﻧﯿﺰ ﺑﻪ ﺗﺮﺗﯿﺐ 20/92 و 2/09 ﻣﯿﻠﯽ ﮔﺮم ﺑﺮ ﮐﯿﻠﻮﮔﺮم اﻧﺪازه ﮔﯿﺮي ﺷﺪ. ﺑﺤﺚ و ﻧﺘﯿﺠﻪﮔﯿﺮي: ﻣﯿﺎﻧﮕﯿﻦ ﺳﺮب و ﮐﺎدﻣﯿﻮم در ﺑﺎﻓﺖ ﺳﺨﺖ ﻧﻤﻮﻧﻪ ﻫﺎ از ﻣﯿﺎﻧﮕﯿﻦ ﺑﻪ دﺳﺖ آﻣﺪه در ﻣﻄﺎﻟﻌﺎت ﻣﺸـﺎﺑﻪ روي آﺑﺰﯾـﺎن ﺧﻠـﯿﺞ ﻓﺎرس ﺑﻪ ﻣﺮاﺗﺐ ﺑﺎﻻﺗﺮ اﺳﺖ. ﺗﺎﺛﯿﺮ ﻣﺘﻘﺎﺑﻞ ﺳﺮب و ﮐﺎدﻣﯿﻮم در اﯾﺠﺎد اﺧﺘﻼل در ﻓﯿﺰﯾﻮﻟﻮژي رﺷﺪ ﺑﻪ اﺛﺒﺎت رﺳﯿﺪه اﺳـﺖ. ﮐـﺎدﻣﯿﻮم در ﺗﻐﺬﯾـﻪ، رﺷﺪ، ﺑﻘﺎ و ﻓﻌﺎﻟﯿﺖ ﻫﺎي ﺗﻮﻟﯿﺪﻣﺜﻠﯽ Coenobita scaevola ﺗﺄﺛﯿﺮ ﻣﻨﻔﯽ دارد.

Background and Objective: The presence of hermit crabs in aquatic species and coastal bird’s food chain and their significant role in environmental remediation highlight the importance of studying these species as biological indicators. Hence, this study assessed the concentration of Lead and Cadmium in sediments of and hard tissue of hermit crabs in KISH Island and compared the results against international standards. Methods: To determine the concentration of Lead and Cadmium, 30 sediment samples and 60 crabs were randomly collected from the south and southeast of KISH Island. By preparation and analysis of specimens, the concentration of heavy metals was determined using atomic absorption spectrophotometer. Findings: The mean concentration of lead and cadmium in the sediments of the south and southeast coasts of Kish Island were 63.20 and 2.94 mg/kg, respectively, both of which are higher than the sediment quality standards of Canada and NOAA. The mean concentration of lead and cadmium in the hard tissue of Coenobita scaevola were 20.92 and 2.09 mg/kg, respectively, which is much higher than the average obtained in similar studies on Persian Gulf aquatic animals. Discussion and Conclusion: The mean concentration of lead and cadmium in the hard tissue of Coenobita Scaevola is much higher than the similar studies on Persian Gulf aquatics. The interaction of lead and cadmium in disrupting growth physiology has been proven. Cadmium has a negative effect on nutrition, growth, survival, and reproductive activities of Coenobita Scaevola.