ﺑﺮآورد ﺗﻮﻟﯿﺪ ﺑﻠﻨﺪ ﻣﺪت ﻋﻠﻮﻓﮥ ﻣﺮاﺗﻊ اﺳﺘﭙﯽ ﻓﺎرس ﺑﺮ اﺳﺎس ﭘﺎراﻣﺘﺮﻫﺎي اﻗﻠﯿﻤﯽ

Estimation of long-term forage production of steppe rangelands of Fars province based on climatic factors parameters

ﻋﻮاﻣﻞ اﻗﻠﯿﻤﯽ ﻣﻬﻢﺗﺮﯾﻦ ﻋﺎﻣﻞ ﺗﺄﺛﯿﺮﮔﺬار ﺑﺮ رﺷﺪ ﭘﻮﺷﺶ ﮔﯿﺎﻫﯽ و ﺗﻮﻟﯿﺪ ﻣﯽﺑﺎﺷﻨﺪ. ﺗﺄﺛﯿﺮ ﻫﺮ ﯾﮏ از اﯾﻦ ﻋﻮاﻣﻞ در ﻫﺮ ﻣﻨﻄﻘﻪ ﺑﺴﺘﻪ ﺑﻪ ﻧﻮع ﭘﻮﺷﺶ ﮔﯿﺎﻫﯽ ﻣﺘﻔﺎوت اﺳــﺖ. در اﯾﻦ ﻣﻄﺎﻟﻌﻪ اﺛﺮ ﻋﻮاﻣﻞ اﻗﻠﯿﻤﯽ )ﺑﺎرﻧﺪﮔﯽ و دﻣﺎ( ﺑﺮ ﺗﻮﻟﯿﺪ ﮔﻮﻧﻪﻫﺎي ﮔﯿﺎﻫﯽ ﻣﻮرد ﭼﺮاي دام در 6 ﺳــﺎﯾﺖ اﺳــﺘﭙﯽ اﺳــﺘﺎن ﻓﺎرس در ﯾﮏ دورة ده ﺳـــﺎﻟﻪ )1377 ﺗﺎ 1386( ﻣﻮرد ﺑﺮرﺳـــﯽ ﻗﺮار ﮔﺮﻓﺖ. ﺟﻬﺖ اﻧﺪازهﮔﯿﺮي ﭘﻮﺷـــﺶ از 60 ﭘﻼت 2 ﻣﺘﺮ ﻣﺮﺑﻌﯽ در ﻃﻮل 4 ﺗﺮاﻧﺴﮑﺖ ﭼﻬﺎر ﺻﺪ ﻣﺘﺮي اﺳﺘﻔﺎده ﺷﺪ و ﺗﻮﻟﯿﺪ ﺑﺎ روش ﻗﻄﻊ و ﺗﻮزﯾﻦ در ﭘﺎﻧﺰده ﭘﻼت در ﻃﻮل ﺗﺮاﻧﺴﮑﺖﻫﺎ اﻧﺪازهﮔﯿﺮي ﮔﺮدﯾﺪ. ﺳﭙﺲ ﺑﺎ اﺳﺘﻔﺎده از راﺑﻄﮥ رﮔﺮﺳﯿﻮﻧﯽ ﺑﯿﻦ ﭘﻮﺷﺶ ﺗﺎﺟﯽ )درﺻﺪ( و ﺗﻮﻟﯿﺪ )ﮐﯿﻠﻮﮔﺮم در ﻫﮑﺘﺎر(، ﺗﻮﻟﯿﺪ ﻣﺎﺑﻘﯽ ﭘﻼتﻫﺎ ﺑﺮاي آن ﺳﺎل ﻣﺤﺎﺳﺒﻪ ﺷﺪ. ﺷﺎﺧﺺﻫﺎي ﻣﻬﻢ اﻗﻠﯿﻤﯽ ﮐﻪ در اﯾﻦ ﺑﺮرﺳﯽ ﻣﻮرد ﺗﺠﺰﯾﻪ و ﺗﺤﻠﯿﻞ ﻗﺮار ﮔﺮﻓﺘﻨﺪ، ﻋﺒﺎرﺗﻨﺪ از: ﺑﺎرﻧﺪﮔﯽ )روزاﻧﻪ، ﻣﺎﻫﺎﻧﻪ، ﺳﺎﻻﻧﻪ، ﺑﺎرﻧﺪﮔﯽ ﻓﺼﻞ روﯾﺶ و ﺑﺎرﻧﺪﮔﯽ ﻓﺼﻞ روﯾﺶ ﺑﻪ ﻋﻼوه ﺳﺎل ﭘﯿﺸﯿﻦ(، دﻣﺎ )ﺳﺎﻻﻧﻪ، ﻣﺎﻫﺎﻧﻪ، ﻓﺼﻞ روﯾﺶ، ﺑﯿﺸﯿﻨﻪ و ﮐﻤﯿﻨﮥ دﻣﺎ(. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﻣﺘﻮﺳﻂ ﺗﺎج ﭘﻮﺷﺶ 6/3 درﺻﺪ و ﻣﺘﻮﺳﻂ ﺗﻮﻟﯿﺪ 128/5 ﮐﯿﻠﻮﮔﺮم در ﻫﮑﺘﺎر ﺑﻮده اﺳﺖ و در ﻣﯿﺎن ﺷﮑﻞﻫﺎي ﻣﺨﺘﻠﻒ روﯾﺸﯽ ﺑﻮﺗﻪايﻫﺎ ﺑﯿﺸﺘﺮﯾﻦ درﺻﺪ ﭘﻮﺷﺶ و ﺗﻮﻟﯿﺪ و ﮔﻨﺪﻣﯿﺎن ﮐﻤﺘﺮﯾﻦ درﺻـﺪ ﭘﻮﺷـﺶ و ﺗﻮﻟﯿﺪ را ﺑﻪ ﺧﻮد اﺧﺘﺼـﺎص دادﻧﺪ. از ﺑﯿﻦ ﺷـﺎﺧﺺﻫﺎي ﻣﻬﻢ اﻗﻠﯿﻤﯽ، ﺑﺎرﻧﺪﮔﯽ ﺳـﺎﻻﻧﻪ و دﻣﺎي ﻣﺮداد ﻣﺎه در ﺗﻤﺎﻣﯽ ﺳـﺎﯾﺖﻫﺎ و ﺑﺎرﻧﺪﮔﯽ ﻓﺼﻞ روﯾﺶ در ﺗﻤﺎﻣﯽ ﺳﺎﯾﺖﻫﺎ ﺑﻪﺟﺰ ﺳﺎﯾﺖ اﯾﺰدﺧﻮاﺳﺖ ﺑﻪ ﻋﻨﻮان ﻣﺆﺛﺮﺗﺮﯾﻦ ﺷﺎﺧﺺ روي ﺗﻮﻟﯿﺪ ﻋﻠﻮﻓﻪ ﻣﺆﺛﺮ ﺑﻮده و ﻫﻤﺒﺴﺘﮕﯽ ﻣﺜﺒﺖ و ﻣﻌﻨﯽداري را ﺑﺎ ﺗﻮﻟﯿﺪ ﻋﻠﻮﻓﻪ ﻧﺸﺎن داد. ﺑﺎ اﺳﺘﻔﺎده از ﺑﺎرﻧﺪﮔﯽ ﺳﺎﻻﻧﻪ ﻣﯽﺗﻮان ﺗﻐﯿﯿﺮات ﺗﻮﻟﯿﺪ ﻋﻠﻮﻓﻪ را در ﻣﺮاﺗﻊ ﻣﻮرد ﺑﺮرﺳﯽ از 50 ﺗﺎ 92 درﺻﺪ و در ﮐﻞ ﻣﺮاﺗﻊ اﺳــﺘﺎن ﻓﺎرس ﺗﺎ 70 درﺻــﺪ ﺑﺮآورد ﻧﻤﻮد. ﻣﯿﺎﻧﮕﯿﻦ ﺗﻮﻟﯿﺪ ﺑﻠﻨﺪﻣﺪت در ﻣﺮاﺗﻊ ﺑﯿﺎﺑﺎن زداﯾﯽ، ﺑﯿﺪاﻋﻠﻢ و اﯾﺰدﺧﻮاﺳــﺖ ﺑﺎ اﺳــﺘﻔﺎده از ﭘﺎراﻣﺘﺮﻫﺎي ﺑﺎرﻧﺪﮔﯽ ﺳﺎﻻﻧﻪ، ﺑﺎرﻧﺪﮔﯽ ﻓﺼﻞ روﯾﺶ و ﺑﯿﺸﯿﻨﮥ دﻣﺎ ﺑﻪ ﺗﺮﺗﯿﺐ 95/2 ،88/3 و 112/7 ﮐﯿﻠﻮﮔﺮم در ﻫﮑﺘﺎر ﺑﺮآورد ﺷﺪ. از ﯾﺎﻓﺘﻪﻫﺎي اﯾﻦ ﺗﺤﻘﯿﻖ ﻣﯽﺗﻮان ﺑﻪ ﻣﻨﻈﻮر ﭘﯿﺶﺑﯿﻨﯽ ﺗﺎجﭘﻮﺷﺶ و ﺗﻮﻟﯿﺪ و در ﻧﻬﺎﯾﺖ ﻇﺮﻓﯿﺖ ﭼﺮاﯾﯽ ﺑﻠﻨﺪﻣﺪت در ﻣﺮاﺗﻊ اﺳﺘﻔﺎده ﻧﻤﻮد.

Climatic factors are the most important factors affecting vegetation growth and production. The impact of each of these factors in each region varies depending on the vegetation type. The effect of climatic factors (rainfall and temperature) on the production of grazed plant species at 6 steppe sites in Fars province over a ten year period (1998 to 2007) was investigated. 60 plots of 2 square meters along 4 transects of four hundred meters were used to measure cover and production was measured by cutting and weighing method in 15 plots along transects. Then, using regression relationship between canopy cover (percent) and production (kg ha-1), the residual plot yield was calculated for that year. Important climatic indices analyzed in this study are: annual rainfall, growing season rainfall (March to June), plus and earlier rainfall, annual temperature, July temperature, August, maximum and minimum temperatures. The results showed that the average canopy cover was 6.3% and the average yield was 128.5 kg / ha and among the different vegetative forms of shrubs had the highest percentage of cover and production and wheat had the lowest cover and production percentage. Among the important climatic indices, annual rainfall and August temperature at all sites and the growing season rainfall at all sites except for the desired site were the most effective indicators on forage production and showed a positive and significant correlation with forage production.