پيش‌بيني اثرات تغيير اقليم بر پراكنش بالقوۀ مكاني (Boraginaceae Juss.) Onosma sabalanica Ponert. و Onosma cornuta H. Riedl. در واحدهاي اقليمي ايران

Prediction the climate change effects on the potential spatial distribution Onosma sabalanica Ponert. and Onosma cornuta H. Riedl. (Boraginaceae Juss.) in climatic units of Iran

ﭘﺪﯾﺪة ﺗﻐﯿﯿﺮ اﻗﻠﯿﻢ ﺑﺰرگﺗﺮﯾﻦ ﭼﺎﻟﺶ زﯾﺴــﺖ ﻣﺤﯿﻄﯽ ﺣﺎل ﺣﺎﺿــﺮ دﻧﯿﺎ ﻣﯽﺑﺎﺷــﺪ. ﭘﯿﺶﺑﯿﻨﯽ اﺛﺮ ﺗﻐﯿﯿﺮ اﻗﻠﯿﻢ ﺑﺮ ﭘﺮاﮐﻨﺶ ﮔﻮﻧﻪﻫﺎي ﮔﯿﺎﻫﯽ ﺣﺴـﺎس و ﺑﺎ ارزش، اﻣﺮي ﻣﻬﻢ در راﺳـﺘﺎي ﻣﺪﯾﺮﯾﺖ و ﺣﻔﺎﻇﺖ آنﻫﺎ ﻣﺤﺴـﻮب ﻣﯽﮔﺮدد. ﺟﻨﺲ .Onosma L )زﻧﮕﻮﻟﻪاي( ﺑﻪ ﻋﻨﻮان ﯾﮏ ﺟﻨﺲ ﺑﺴﯿﺎر ﻏﻨﯽ از ﻃﺎﯾﻔﮥ .Lithospermeae Dumort در ﺗﯿﺮة ﮔﺎوزﺑﺎن )Boraginaceae( ﻣﯽﺑﺎﺷﺪ ﮐﻪ داراي 52 ﮔﻮﻧﻪ در اﯾﺮان اﺳﺖ ﮐﻪ ﺑﯿﺶ از ﻧﯿﻤﯽ از آنﻫﺎ اﻧﺪﻣﯿﮏ اﯾﺮان ﻣﯽﺑﺎﺷـــﺪ. ﮔﻮﻧﻪﻫﺎي .Onosma cornuta H. Riedl و .Onosma sabalanica Ponert از ﮔﻮﻧﻪﻫﺎي ﺑﻮﻣﯽ و ﺑﺴــﯿﺎر ﻧﺎدر اﯾﻦ ﺟﻨﺲ در اﯾﺮان ﻣﯽﺑﺎﺷــﺪ. ﻫﺪف اﯾﻦ ﻣﻄﺎﻟﻌﻪ، ﺑﺮرﺳــﯽ اﺛﺮ ﺗﻐﯿﯿﺮ اﻗﻠﯿﻢ ﺑﺮ ﭘﺮاﮐﻨﺶ ﻣﮑﺎﻧﯽ اﯾﻦ 2 ﮔﻮﻧﻪ در آﯾﻨﺪه اﺳﺖ. در اﯾﻦ راﺳﺘﺎ، ﺑﺎ اﺳﺘﻔﺎده از اﺑﺰار ﻣﺪلﺳﺎزي ﭘﺮاﮐﻨﺶ ﮔﻮﻧﻪ )SDM(، ﻫﺸﺖ اﻟﮕﻮرﯾﺘﻢ ﻣﺨﺘﻠﻒ ) ,GLM, GAM, GBM, RF FDA, MARS, ANN, SRE( در ﺳﻨﺎرﯾﻮﻫﺎي ﻣﺨﺘﻠﻒ ﺧﻮ ﺷﺒﯿﻨﺎﻧﻪ )RCP2.6( و ﺑﺪﺑﯿﻨﺎﻧﻪ )RCP8.5( ﭘﺮاﮐﻨﺶ ﻣﮑﺎﻧﯽ آﯾﻨﺪة اﯾﻦ ﮔﻮﻧﻪ را ﺑﺮاي ﺳﺎل 2050 ﺑﺎ ا ﺳﺘﻔﺎده از ﻣﺪل اﻧ ﺴﻤﺒﻞ در ﻣﺤﯿﻂ ﻧﺮم اﻓﺰاري R ﭘﯿﺶﺑﯿﻨﯽ ﻧﻤﻮدهاﻧﺪ. ﻧﺘﺎﯾﺞ ﻧ ﺸﺎن داد ﮐﻪ ﻋﻤﻠﮑﺮد ﺗﻤﺎﻣﯽ ﻣﺪلﻫﺎ ﺑﺮ اﺳﺎس ﺷﺎﺧﺺ TSS، ﻋﺎﻟﯽ و ﻣﺪلﺳﺎزي ﭘﺮاﮐﻨﺶ ﮔﻮﻧﮥ ﻣﻮرد ﻧﻈﺮ ﺑﺎ اﻃﻤﯿﻨﺎن آﻣﺎري ﺑﺎﻻﯾﯽ اﻧﺠﺎم ﺷﺪه اﺳﺖ. ﻧﺘﺎﯾﺞ ﻫﻤﭽﻨﯿﻦ ﻧﺸﺎن داد ﮐﻪ ﭘﺮاﮐﻨﺶ اﯾﻦ دو ﮔﻮﻧﻪ در ﻫﺮ دو ﺳﻨﺎرﯾﻮي ﺧﻮﺷﺒﯿﻨﺎﻧﻪ و ﺑﺪﺑﯿﻨﺎﻧﮥ ﺳﺎل 2050 ﺑﺎ ﮐﺎﻫﺶ ﭼﺸﻤﮕﯿﺮي روﺑﻪرو ﺑﻮده ﮐﻪ ﻧﯿﺎز ﺑﻪ ﺑﻪﮐﺎرﮔﯿﺮي اﺳﺘﺮاﺗﮋيﻫﺎي ﻻزم ﺟﻬﺖ ﺣﻔﺎﻇﺖ از اﯾﻦ دو ﮔﯿﺎه ارزﺷﻤﻨﺪ ﻣﯽﺑﺎﺷﺪ.

The climate change is the greatest environmental challenge facing the world today. The prediction of the effect of climate change on the distribution of sensitive and valuable plant species is considered important in the management and conservation of them. Onosma L. as a very rich taxa from Lithospermeae Dumort. tribe in Boraginaceae family including 52 species in Iran wich more than half of them are endemic to Iran. The Onosma sabalanica Ponert. and Onosma cornuta H. Riedl. are the rare and endemic species of Onosma L. in Iran. Objective of the present study was to predict the effects of the climate change on the spatial distribution of these plants at future. In this regard, with using species distribution model's tool (SDM), different algorithms (GLM, GAM, GBM, RF, CTA, FDA, MARS, ANN, SRE) in different optimistic (RCP2.6) and pessimistic (RCP8.5) scenarios predicted the future spatial distribution of this species for 2050 by an ensemble model in R statistical software. The results showed that the performance of all models based on TSS index was excellent and modeling of the distribution of the species had been done with high statistical reliability. The results also represented that the distribution of these species in both optimistic and pessimistic scenarios of 2050 had been significantly reduced which requires to apply strategies for protecting of this valuable plants.