كليدواژه :
خطرپذيري آلودگي , آبهاي زيرزميني , تحليل حساسيت , ضريب همبستگي , P-DRASTIC
چكيده فارسي :
زﻣﯿﻨﻪ و ﻫﺪف: روشﻫﺎي آﻣﺎري ﺑﻪﻃﻮر ﮔﺴﺘﺮدهاي در ﻣﻄﺎﻟﻌﺎت ﻣﺤﯿﻂزﯾﺴﺘﯽ ﺟﻬﺖ ارزﯾﺎﺑﯽ ﻣﺨﺎﻃﺮات ﻃﺒﯿﻌﯽ اﺳﺘﻔﺎده ﻣـﯽ ﺷـﻮد. از آﺳـﯿﺐ ﭘﺬﯾﺮي آﺑﻬﺎي زﯾﺮزﻣﯿﻨﯽ ﺑﻪﮐﻤﮏ روشﻫﺎي آﻣﺎري ﺑﺮاي ﺣﻤﺎﯾﺖ از ﺗﺼﻤﯿﻢﮔﯿﺮي در ﻣﻮرد ﻣﺪﯾﺮﯾﺖ و ﺑﺮﻧﺎﻣﻪرﯾﺰي زﯾﺴﺖﻣﺤﯿﻄﯽ اﺳـﺘﻔﺎده ﻣـﯽ ﺷﻮد. در اﯾﻦ ﺗﺤﻘﯿﻖ از ﺑﻬﯿﻨﻪﺳﺎزي ﭘﺎراﻣﺘﺮﻫﺎي ﻣﺪل Pesticide DRASTIC ،DRASTIC و ﻻﯾﻪ ﮐﺎرﺑﺮي اراﺿﯽ )(LU ﺑﺮاﺳﺎس روشﻫﺎي آﻣﺎري ﺟﻬﺖ ﻣﺪلﺳﺎزي ﺧﻄﺮﭘﺬﯾﺮي آﻟﻮدﮔﯽ آﺑﻬﺎي زﯾﺮزﻣﯿﻨﯽ ﺣﻮزه آﺑﺮﯾﺰ ﺟﻨﻮب درﯾﺎﭼﻪ ﻧﻤﮏ اﺳﺘﻔﺎده ﮔﺮدﯾﺪه اﺳﺖ.
روش ﺑﺮرﺳﯽ: در اﯾﻦ روش ﻻﯾﻪﻫﺎي اﻃﻼﻋﺎﺗﯽ در ﻣﺤﯿﻂ GIS ﺗﻬﯿﻪ، رﺗﺒﻪﺑﻨـﺪي )ﻗﻄﻌـﯽ و ﻓـﺎزي -آﻣـﺎر ي(، وزندﻫـﯽ )اﺻـﻠﯽ و آﻣـﺎري( و ﺑﻪروش ﻫﻢﭘﻮﺷﺎﻧﯽ ﺷﺎﺧﺺ ﺗﻠﻔﯿﻖ ﮔﺮدﯾﺪﻧﺪ. ﺑﺮاي ﻣﺪلﺳﺎزي از رﮔﺮﺳﯿﻮن ﻏﯿﺮﺧﻄﯽ ﺟﻬﺖ رﺗﺒﻪﺑﻨﺪي ﻓـﺎزي -آﻣـﺎري )ﻫـﻢ ﻣﻘﯿـﺎس ﺳـﺎزي( و از ﺿﺮاﯾﺐ ﻫﻤﺒﺴﺘﮕﯽ ﭘﯿﺮﺳﻮﻧﯽ ﺑﯿﻦ ﻏﻠﻈﺖ ﻧﯿﺘﺮات ﺑﺎ ﭘﺎراﻣﺘﺮﻫـﺎي ﻫـﻢ ﻣﻘﯿـﺎس ﺷـﺪه ﻣـﺪل P-DRASTIC ،DRASTIC و ﺗﺤﻠﯿـﻞ ﺣﺴﺎﺳـﯿﺖ )ﺣﺬف ﭘﺎراﻣﺘﺮي، ﺗﮏ ﭘﺎراﻣﺘﺮي( ﺟﻬﺖ ﺗﻌﯿﯿﻦ و ﺗﺼﺤﯿﺢ وزن ﻣﻨﺎﺳﺐ ﭘﺎراﻣﺘﺮﻫﺎ اﺳﺘﻔﺎده ﺷﺪ. ﻫﻤﭙﻨﯿﻦ ﺟﻬﺖ ﺗﻌﯿﯿﻦ ﺗﺎﺛﯿﺮ ﮐﺎرﺑﺮيﻫﺎي اراﺿﯽ و رﺗﺒﻪﺑﻨﺪي آن از ﻣﺪل ﺗﺨﺮﯾﺐ ﻣﺨﺪوم ﺑﺮ اﺳﺎس ﻣﯿﺰان ﭘﺘﺎﻧﺴﯿﻞ آﻟﻮدﮔﯽ و ﻧﯿﺘﺮات ﻣﺸﺎﻫﺪهﺷﺪه آﺑﻬﺎي زﯾﺮزﻣﯿﻨﯽ اﺳﺘﻔﺎده ﮔﺮدﯾﺪ.
ﯾﺎﻓﺘﻪ ﻫﺎ: در ﻧﺘﯿﺠﻪ ﻣﺪل P-RASIC-LU و RASIC-LU ﺑﺮ اﺳﺎس رﺗﺒﻪﺑﻨﺪي و وزندﻫﯽ آﻣـﺎري و ﺗﺤﻠﯿـﻞ ﺣﺴﺎﺳـﯿﺖ ﺣـﺬف ﭘـﺎراﻣﺘﺮي، ﺿﺮﯾﺐ ﻫﻤﺒﺴﺘﮕﯽ 62 درﺻﺪ و ﺳﻄﺢ ﻣﻌﻨﯽداري آﻣﺎري 0/01 را ﻧﺸﺎن داده و ﺑﺎ ﭘﺎراﻣﺘﺮﻫﺎي ﻧﺮخ ﺗﻐﺬﯾﻪ ﺧﺎﻟﺺ، ﻣﺤﯿﻂ آﺑﺨﻮان، ﻣﺤﯿﻂ ﺧـﺎك، اﺛﺮ ﻣﻨﻄﻘﻪ ﻏﯿﺮاﺷﺒﺎع، ﻫﺪاﯾﺖ ﻫﯿﺪروﻟﯿﮑﯽ و ﮐﺎرﺑﺮي اراﺿﯽ ﺑﻪﺗﺮﺗﯿﺐ ﺑـﺎ وزﻧ ﻬـﺎي 2/0 ،2/0 ،3/1 ،4/1 ،4/0 ،3/1 و 3/03 ،4/15 ،4/63 ،2/50، 1/96، 2/00 ﺑﻪ ﻋﻨﻮان ﺑﻬﺘﺮﯾﻦ ﻣﺪل اﻧﺘﺨﺎﺑﯽ ﻣﺸﺨﺺ ﺷﺪ. ﺑﺮ اﺳﺎس اﯾﻦ ﻣﺪل ﻗﺴﻤﺖﻫﺎي ﻏﺮﺑﯽ و ﺟﻨﻮﺑﯽ آﺑﺨﻮان ﺑﻪ دﻟﯿﻞ ﻧـﺮخ ﺗﻐﺬﯾـﻪ ﺑـﺎﻻ و ﻣﻮاد درﺷﺖ داﻧﻪ در ﻧﺎﺣﯿﻪ ﻏﯿﺮ اﺷﯿﺎع، ﺧﺎك و ﻣﺤﯿﻂ آﺑﺨﻮان داراي ﺧﻄﺮﭘﺬﯾﺮي آﻟﻮدﮔﯽ زﯾﺎدي ﻣﯽﺑﺎﺷﺪ.
ﺑﺤﺚ و ﻧﺘﯿﺠﻪﮔﯿﺮي: ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ اﯾﻨﮑﻪ در ﺑﺎزﺑﯿﻨﯽ وزن و رﺗﺒﻪ ﭘﺎراﻣﺘﺮﻫﺎي ﻣﺪل ﺑﺎ اﺳﺘﻔﺎده از روش آﻣﺎري و GIS ﺗﺎ ﺣﺪودي ﻧﻈﺮات ﺷﺨﺼﯽ ﻣﺤﺪود ﺷﺪه و ﺑﺎﻋﺚ اﻓﺰاﯾﺶ ﺻﺤﺖ ﻣﺪل ﮔﺮدﯾﺪه اﺳﺖ. اﯾﻦ روش ﻧﺘﺎﯾﺞ ﻣﻄﻠﻮﺑﯽ ﺑﺮاي ﻣﺪلﺳﺎزي ﺧﻄﺮﭘﺬﯾﺮي آﻟﻮدﮔﯽ ﺑﻪ دﻧﺒﺎل داﺷﺘﻪ اﺳﺖ.
چكيده لاتين :
Background and Purposes: Statistical methods are widely used in environmental studies to evaluate natural hazards. Within groundwater vulnerability in particular, statistical methods are used to support decisions about environmental planning and management. In this study, the optimized of DRASTIC, Pesticide DRASTIC model parameters and land use layers (LU) were used to assess of pollution risk in catchment basin aquifer in south of Namak lake using of statistical methods.
Methods: Information layers were prepared, rated (deterministic and fuzzy-statistical), weighted (original and statistical) and combined (by Index-Overlay method) in GIS environment. For modeling, from nonlinear regression for fuzzy-statistical rating (scaling) and the Pearson correlation coefficients between of nitrate concentrations with scaling parameters of DRASTIC, P-DRASTIC model and sensitivity analysis (removal and single-parameter) were performed to determine and modify of parameters weighted.
Results: As result P-RASIC-LU and RASIC-LU model with statistical rating and weighting, removal-parameter sensitivity analysis, determine as best selection model based on correlation coefficient = 62%, P-value = 0.01 and with parameters of net recharge, aquifer media, soil media, impact of vadose zone, hydraulic conductivity and land use with the weighty values of 3.1, 4.0, 4.1, 3.1, 2, 2 and 2.5, 4.63, 4.15, 3.03, 2, 1.96 consequently. According to this model, western and southern parts of the aquifer has high pollution risk due to high net recharge and coarse-grain material in the impact of vadose zone, soil and aquifer media.
Conclusion: Since reviewing of weight and rank of model parameters is limited personal opinions and increased model validation using statistical methods and GIS, It can be expected that favorable results to be followed for optimization of pollution risk model
