شناسايي منابع آورد رسوب در حوضه آبريز با استفاده از تصاوير ماهوارهاي، سيستم هاي و بكارگيري اطلاعات هيدروژئولوژيكي )GIS) اطلاعات جغرافيايي )مطالعه موردي: حوضه آبخيز سد دز(

Possibility Using Remote Sensing for Estimation Sediment Resources to Reservoir of Exploitation Dams

رﺳﻮبﮔﺬاري در ﻣﺨﺎزن ﭘﯿﺶﻧﯿﺎز ﻣﺪﯾﺮﯾﺖ ﭘﺎﯾﺪار آب ﻣﯽﺑﺎﺷﺪ و ﺳﺪ دز ﺑﻪ دﻟﯿﻞ ﺗﻨﻈﯿﻢ ﻓﺮﮐﺎﻧﺲ ﺑﺮق ﮐﺸﻮر از اﻫﻤﯿﺖ ﺧﺎﺻﯽ ﺑﺮﺧﻮردار اﺳﺖ. از اﻫﺪاف ﮐﻠﯽ اﯾﻦ ﻣﻄﺎﻟﻌﻪ، ﺷﻨﺎﺳﺎﯾﯽ ﻣﻨﺎﺑﻊ آورد رﺳﻮب در ﺣﻮﺿﻪ آﺑﺮﯾﺰ ﺑﺎ اﺳﺘﻔﺎده از ﺗﺼﺎوﯾﺮ ﻣﺎﻫﻮارهاي و ﺳﯿﺴﺘﻢ اﻃﻼﻋﺎت ﺟﻐﺮاﻓﯿﺎﯾﯽ )GIS( ﺑﺎ ﺑﻪﮐﺎرﮔﯿﺮي اﻃﻼﻋﺎت ﻫﯿﺪروژﺋﻮﻟﻮژﯾﮑﯽ ﻣﯽﺑﺎﺷﺪ. ﺑﻪ ﻫﻤﯿﻦ ﻣﻨﻈﻮر ﺑﺎ درﯾﺎﻓﺖ ﻧﺘﺎﯾﺞ آزﻣﺎﯾﺸﮕﺎﻫﯽ ﮐﺎﻧﯽﺷﻨﺎﺳﯽ رﺳﻮﺑﺎت ﺳﺪ ﻣﺸﺨﺺ ﺷﺪ ﮐﻪ 75 درﺻﺪ رﺳﻮﺑﺎت را ﮐﺎﻧﯽﻫﺎي ﮐﻠﺴﯿﺖ، دوﻟﻮﻣﯿﺖ و ﮐﻮارﺗﺰ ﺗﺸﮑﯿﻞ ﻣﯽدﻫﻨﺪ. ﺑﺎ اﻧﺠﺎم ﭘﺮدازش ﺗﺼﺎوﯾﺮ ﺳﻨﺠﻨﺪه ASTER ﺑﻪ روشﻫﺎي ﻧﺴﺒﺖ ﺑﺎﻧﺪي، SAM و PCA ﻣﻨﺎﺑﻊ آورد رﺳﻮﺑﺎت ﻣﺸﺨﺺ ﺷﺪﻧﺪ و ﺑﺎ ﺗﻄﺒﯿﻖ ﺑﺎ ﺳﺎزﻧﺪﻫﺎي زﻣﯿﻦﺷﻨﺎﺳﯽ ﻣﻨﻄﻘﻪ و ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻟﯿﺘﻮﻟﻮژي ﺳﺎزﻧﺪﻫﺎ ﺻﺤﺖ ﻧﺘﺎﯾﺞ ﺑﺮرﺳﯽ ﺷﺪ؛ اﻣﺎ ﮐﺎﻧﯽ ﮐﻮارﺗﺰ ﺑﻪ دﻟﯿﻞ اﯾﻨﮑﻪ در ﻣﺤﺪوده ﻣﺮﺋﯽ و ﻣﺎدون ﻗﺮﻣﺰ ﺑﺎﻧﺪ ﺟﺬب و ﺑﺎزﺗﺎب ﺷﺎﺧﺼﯽ ﻧﺪارد ﺑﺎ روشﻫﺎي ﻣﺬﮐﻮر ﺑﺎرز ﻧﺸﺪ و ﺑﻪ ﻫﻤﯿﻦ دﻟﯿﻞ روش ﺗﺮﮐﯿﺐ ﺑﺎﻧﺪي )13،12،10( )RGB( ﺑﻪﮐﺎرﺑﺮده ﺷﺪ ﮐﻪ ﺑﺮاﺳﺎس ﺿﺮﯾﺐ ﻓﺎﮐﺘﻮر ﺑﻬﯿﻨﻪ ﺑﻬﺘﺮﯾﻦ ﻧﺘﯿﺠﻪ را درﺑﺮ دارد و ﻣﻨﺎﻃﻖ داراي ﮐﻮارﺗﺰ ﺑﺎ درﺟﻪ ﺑﺎﻻ ﺑﻪ رﻧﮓ ﻗﺮﻣﺰ و ﻣﻨﺎﻃﻖ ﺑﺎ درﺟﻪ ﻣﺘﻮﺳﻂ ﺑﻪ رﻧﮓ ﺻﻮرﺗﯽ ﺑﺎرز ﺷﺪ. ﺑﺮﭘﺎﯾﻪ ﻧﺘﺎﯾﺞ ﺗﺤﻘﯿﻖ ﺣﺎﺿﺮ ﻣﯽﺗﻮان ﮔﻔﺖ ﮐﻪ ﺗﺼﺎوﯾﺮ ﻣﺎﻫﻮارهاي ﻣﯽﺗﻮاﻧﻨﺪ اﺑﺰار ﻣﻨﺎﺳﺒﯽ ﺑﺮاي ﺷﻨﺎﺳﺎﯾﯽ ﻣﻨﺎﺑﻊ آورد رﺳﻮﺑﺎت در ﺣﻮﺿﻪ آﺑﺮﯾﺰ ﺳﺪﻫﺎ ﺑﺎﺷﻨﺪ.

Sedimentation in reservoirs is a prerequisite for sustainable water management. The Dez dam is very important the country because of its role in electricity frequency adjustment. The main objective of this research is to identify the sources of sediment in the catchment using satellite images, GIS and hydro-geological information. For this purpose, the lab results of sediments mineralogy revealed that 75 percent of sediments constitute calcite, dolomite and quartz. By processing the ASTER images and applying the methods such as Band Ratio, SAM and PCA sediments resources were identified and by matching geologic formations lithology formations of the study area accuracy of the results were verified. However, the quartz mineral could not be enhanced using the mentioned methods due to its low absorptance and reflectance in visible and infrared regions For this reason the band composition (RGB) (10, 12, 13) method was applied and the best results were revealed based on the Optimum Index Factor (OIF) which then demonstrated the high purity quartz area in red and the mid purity in pink color. The results concluded that the satellite images can be a useful tool to identify sources of sediments in the reservoirs dams.