بررسي و تهيه نقشه بيابانزايي بر اساس مدل ايراني ارزيابي پتانسيل بيابانزايي(IMDPA) با تأكيد بر دو معيار خاك و پوشش گياهي (مطالعه موردي: فارياب-استان كرمان)

Investigation and Preparation of Desertification Map Based on Iranian Model of Desertification Potential (IMDPA) with an emphasis on two criteria of soil and vegetation (Case study: Faryab-Kerman Province)

زﻣﯿﻨﻪ و ﻫﺪف: ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﻔﻬﻮم ﺑﯿﺎﺑﺎن زاﯾﯽ ﮐﻪ ﻋﺒﺎرت اﺳﺖ از ﺗﺨﺮﯾﺐ اراﺿﯽ در ﻧﻮاﺣﯽ ﺧﺸﮏ، ﻧﯿﻤﻪ ﺧﺸﮏ و ﻧﯿﻤﻪ ﻣﺮﻃﻮب ﺧﺸﮏ ﻧﺎﺷـﯽ از ﻋﻮاﻣﻞ ﻣﺘﻌﺪدي ﭼﻮن ﺗﻐﯿﯿﺮات اﻗﻠﯿﻤﯽ و ﻓﻌﺎﻟﯿﺖ ﻫﺎي اﻧﺴﺎﻧﯽ، اﯾﻦ ﭘﺪﯾﺪه ﻣﺪت ﻫﺎﺳﺖ ﮐﻪ ﯾﮏ ﻣﺸﮑﻞ ﺟـﺪي اﻗﺘﺼـﺎدي، اﺟﺘﻤـﺎﻋﯽ و زﯾﺴـﺖ ﻣﺤﯿﻄﯽ در ﺑﺴﯿﺎري از ﮐﺸﻮر ﻫﺎي ﺷﻨﺎﺧﺘﻪ ﺷﺪه اﺳﺖ. ﻫﺪف از ﻣﻄﺎﻟﻌﻪ ﺣﺎﺿﺮ، ﺑﺮرﺳﯽ ﺑﯿﺎﺑﺎنزاﯾﯽ ﺷﻬﺮﺳﺘﺎن ﻓﺎرﯾﺎب در ﺟﻨﻮب اﺳـﺘﺎن ﮐﺮﻣـﺎن ﺑﺎ اﺳﺘﻔﺎده از روش اﯾﺮاﻧﯽ IMDPA ﻣﯽﺑﺎﺷﺪ. روش ﺑﺮرﺳﯽ: ﺗﺤﻘﯿﻖ ﺣﺎﺿﺮ ﺑﻪ ﻣﻨﻈﻮر ﺑﺮرﺳﯽ ﺷﺪت ﺑﯿﺎﺑﺎن زاﯾﯽ اراﺿﯽ ﺣﻮزه ﻓﺎرﯾﺎب در ﻣﻨﺎﻃﻖ ﺧﺸﮏ ﺟﻨﻮب اﺳـﺘﺎن ﮐﺮﻣـﺎن ﺑـﺎ ﺗﺄﮐﯿـﺪ ﺑـﺮ ﻣﻌﯿﺎرﻫﺎي ﺧﺎك و ﭘﻮﺷﺶ ﮔﯿﺎﻫﯽ ﺑﺎ اﺳﺘﻔﺎده از ﻣﺪل اﯾﺮاﻧﯽ ﺑﯿﺎﺑﺎن زاﯾﯽ ﺻﻮرت ﮔﺮﻓﺖ. ﺑﺎ اﺳﺘﻔﺎده از اﯾﻦ ﻣﺪل اﻣﺘﯿـﺎزات ﻫـﺮ ﺷـﺎﺧﺺ در ﻣﻌﯿـﺎ ر ﻣﺮﺑﻮﻃﻪ ﻣﺸﺨﺺ و ارزش ﻫﺮ ﻣﻌﯿﺎر ﺑﺎ ﻣﺤﺎﺳﺒﻪ ﻣﯿﺎﻧﮕﯿﻦ ﻫﻨﺪﺳﯽ اﻣﺘﯿﺎز ﺷﺎﺧﺺ ﻫﺎي آن ﻣﺸﺨﺺ ﮔﺮدﯾﺪ و ﭘﺲ از آن ﻫـﺮ ﯾـﮏ از ﻣﻌﯿﺎرﻫـﺎ ﺑـﻪ ﺻﻮرت ﻻﯾﻪ ﻫﺎي اﻃﻼﻋﺎﺗﯽ وارد 9.3 ArcGIS ﺷﺪﻧﺪ. ﺑﺎ روي ﻫﻢ ﮔﺬاري و ﺗﻠﻔﯿﻖ ﻻﯾﻪ ﻫﺎي رﺳـﺘﺮي ﻣﻌﯿﺎرﻫـﺎي ﻣـﺬﮐﻮر و ﻣﺤﺎﺳـﺒﻪ ﻣﯿـﺎﻧﮕﯿﻦ ﻫﻨﺪﺳﯽ ﻣﻌﯿﺎرﻫﺎ ﺑﻪ ﮐﻤﮏ ﻓﺮﻣﻮل 1/2)DM=(VQI*SQI و ﺗﺠﺰﯾﻪ و ﺗﺤﻠﯿﻞ آن ﺑـﺎ اﺳـﺘﻔﺎده از ﻣـﺪل IMDPA ﻧﻘﺸـﻪ ﺷـﺪت ﺑﯿﺎﺑـﺎن زاﯾـﯽ ﻣﻨﻄﻘﻪ ﺑﺪﺳﺖ آﻣﺪ. ﯾﺎﻓﺘﻪ ﻫﺎ: ﻧﺘﺎﯾﺞ ﻧﺸﺎن ﻣﯽ دﻫﺪ از ﺳﻄﺢ زﻣﯿﻦ ﻫﺎي ﻣﻨﻄﻘﻪ ﺑﻪ ﺗﺮﺗﯿﺐ 14/53 درﺻﺪ در ﮐﻼس ﮐﻢ ﯾﺎ ﻧﺎﭼﯿﺰ، 33/69 درﺻﺪ در ﮐﻼس ﻣﺘﻮﺳـﻂ و 51/78 درﺻﺪ در ﮐﻼس ﺷﺪﯾﺪ ﺑﯿﺎﺑﺎن زاﯾﯽ اﺳﺖ. ﻫﻤﭽﻨﯿﻦ ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﺷﺎﺧﺺ ﺗﺠﺪﯾﺪ ﺣﯿﺎت از ﻣﻌﯿـﺎر ﭘﻮﺷـﺶ ﮔﯿـﺎﻫﯽ ﺑـﺎ ارزش ﻋـﺪدي 3/82 ﺑﯿﺶ ﺗﺮﯾﻦ ﺗﺄﺛﯿﺮ را در ﺑﯿﺎﺑﺎن زاﯾﯽ ﻣﻨﻄﻘﻪ داﺷﺘﻪ اﺳﺖ.

Background and Objective: According to the concept of desertification, which is land degradation in dry areas, the semi-arid, and dry sub-humid due to many factors such as climate change and human activities, this phenomenon has long been known as a serious problem in terms of economic, social, and environmental in many countries. The purpose of this study was to study the desertification of Faryab city in southern Kerman province using Iranian IMDPA method. Method:The aim of this study was assessed desertification potential of Faryab region in the arid region of south of Kerman province by using the Iranian model of desertification potential assessment (IMDPA) on soil and vegetation cover indicators.Each criterion was assessed based on the selected indices which result in qualitative mapping of each criterion cased on geometric average of the indices. Thematic databases, with a scale of 1:50000 were integrated and elaborated in Arc GIS 9.3. By laminate of thematic databases layers and using this formula DM=(VQI×SQI)1/2 to Calculate the geometric mean Criteria. Then Desertification intensity map was obtained with analysis IMDPA Model. Findings: Results indicated that 14.53% of study area classified as low class, 33.69% is classified as moderate class and 51.78% of area classified as a severe class of desertification. Analysis of desertification criteria in Faryab region showed that among study criteria, regeneration of vegetation of vegetation cover is a major problem with a geometric average of 3.82. Discussion and Conclusion: According to the results of this research, which indicates the importance of vegetation in desertification, it is suggested that a deeper investigation of the appropriate methods of remediation and improvement of the rangelands of the region be undertaken by the Natural Resources Department. In the case of lack of attention from the authorities, about 50% of other (medium and low desertification classes) will be subject to severe destruction, which will lead to damage to other elements of the ecosystem, including wildlife, and so on.