پديد آورندگان :
مرادي، عزت اله , حشمتي، غلامعلي دانشگاه علوم كشاورزي و منابع طبيعي گرگان - دانشكده مرتع و آبخيزداري - گروه مرتعداري , دهقاني، اميراحمد دانشگاه علوم كشاورزي و منابع طبيعي گرگان - دانشكده مهندسي آب و خاك - گروه مهندسي آب
كليدواژه :
ابعاد لكه هاي گياهي , برگشت پذيري اكولوژيكي , مراتع كوهسري , نرخ دامگذاري
چكيده فارسي :
رﻣﺰ درك ﻧﺤﻮه ﻏﺎﻟﺒﯿﺖ ﮔﻮﻧﻪ ﻫﺎ در اﮐﻮﺳﯿﺴﺘﻢ ﻫﺎ، ﻣﻬﺎﺟﺮت ﮔﻮﻧﻪ ﻫﺎ و اﺛﺮ آﺷﻔﺘﮕﯽ ﻫﺎ ﺑﺮ اﮐﻮﺳﯿﺴﺘﻢ ﻧﯿﺎزﻣﻨـﺪ ﻓﻬـﻢ و درك ﺻﺤﯿﺢ ﺑﺮﮔﺸﺖ ﭘﺬﯾﺮي اﮐﻮﻟﻮژﯾﮑﯽ اﺳﺖ. ﻫﺪف اﺻﻠﯽ اﯾﻦ ﻣﻄﺎﻟﻌـﻪ ﻣﻌﺮﻓـﯽ ﻣﻬﻤﺘـﺮﯾﻦ وﯾﮋﮔـﯽ ﻫـﺎي ﺳـﺎﺧﺘﺎري و ﻋﻤﻠﮑﺮدي ﻣﺮﺗﻊ در ﺗﻌﯿﯿﻦ ﺑﺮﮔﺸﺖ ﭘﺬﯾﺮي ﻣﺮﺗﻊ اﺳﺖ. ﻣﻨﻄﻘﻪ ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﺷﻬﺮﺳﺘﺎن ﺳﻤﯿﺮم (ﻣﺮاﺗﻊ ﮐﻮﻫﺴـﺮي ﻣﻨﻄﻘـﻪ وﻧﮏ) واﻗﻊ در ﺟﻨﻮب اﺳﺘﺎن اﺻﻔﻬﺎن اﺳﺖ. وﯾﮋﮔﯽ ﻫﺎي ﻣﻮرد ﻣﻄﺎﻟﻌﻪ؛ ﺳﻬﻢ ﮔﻮﻧﻪ ﺷﺎﺧﺺ در ﺗﺮﮐﯿﺐ ﮔﻮﻧﻪ اي، ﻟﮑﻪ ﮔﯿﺎﻫﯽ، ﻓﻀﺎي ﺑﯿﻦ ﻟﮑﻪ اي، ﺗﻨﻮع ﮔﻠﺴﻨﮓ ﻫﺎ، ﻣﻘﺪار ﻧﯿﺘﺮوژن ﺧﺎك، ﻣﻘﺪار ﭘﺘﺎﺳﯿﻢ ﺧﺎك و ﻣﻘﺪار ﮐﺮﺑﻦ آﻟﯽ ﺧﺎك و آﺷﻔﺘﮕﯽ وارده ﻧﯿﺰ 5 ﻧﺮخ داﻣﮕﺬاري (1، 1/5، 2، 2/5 و 3 واﺣﺪ داﻣﯽ) در ﻫﮑﺘﺎر اﺳﺖ. ﻧﺮخ ﻫﺎي داﻣﮕﺬاري ﺑﻪ ﻣﺪت 4 ﺳـﺎل ﺑـﺎ اﺟـﺮاي 5 ﺳﻨﺎرﯾﻮ ﻣﺪﯾﺮﯾﺘﯽ (ﭼﺮا و ﻗﺮق ﺑﻪ ﺻﻮرت ﻣﺘﻨﺎوب و ﻣﺘﻮاﻟﯽ) اﻋﻤﺎل و ﻣﻄﺎﻟﻌﻪ ﺷﺪ. ﺑﺮداﺷﺖ داده ﻫﺎ ﺑﻪ روش ﻧﻤﻮﻧـﻪ ﺑـﺮداري ﺗﺼﺎدﻓﯽ ﺑﺎ اﺳﺘﻔﺎده از ﺗﺮاﻧﺴﮑﺖ و واﺣﺪﻫﺎي ﻧﻤﻮﻧﻪ ﺑﺮداري ﺗﻮ در ﺗﻮ اﻧﺠﺎم ﺷﺪ. آﻧﺎﻟﯿﺰ آﻣﺎري داده ﻫﺎ ﺑﺎ اﺳـﺘﻔﺎده از ﺗﺠﺰﯾـﻪ ﻣﻮﻟﻔﻪ ﻫﺎي اﺻﻠﯽ و ﻣﺤﺎﺳﺒﻪ ﺗﻨﻮع ﺑﺘﺎ اﻧﺠﺎم ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد وﯾﮋﮔﯽ ﻫﺎي ﺳﻬﻢ ﮔﻮﻧﻪ ﺷﺎﺧﺺ در ﺗﺮﮐﯿﺐ ﮔﻮﻧﻪ اي، ﻣﯿﺰان ﮐﺮﺑﻦ آﻟﯽ ﺧﺎك، ﻟﮑﻪ ﻫﺎي ﮔﯿﺎﻫﯽ و ﺗﻨﻮع ﮔﻠﺴﻨﮓ ﻫﺎ ﺑﻪ ﺧﻮﺑﯽ ﻧﺸﺎﻧﮕﺮ ﻣﯿﺰان ﻓﺸﺎر ﺑﺮ اﮐﻮﺳﯿﺴﺘﻢ و درﺟﻪ ﺑﺮﮔﺸﺖ ﭘﺬﯾﺮي اﮐﻮﻟﻮژﯾﮑﯽ اﮐﻮﺳﯿﺴﺘﻢ ﻣﺮﺗﻊ ﻫﺴﺘﻨﺪ. در ﻣﺪﯾﺮﯾﺖ اﮐﻮﺳﯿﺴﺘﻢ ﻫﺎي ﻣﺮﺗﻌﯽ ﻣﯽ ﺗﻮان از وﯾﮋﮔﯽ ﻫﺎي ذﮐﺮ ﺷﺪه ﺑﻪ ﻋﻨﻮان ﺷﺎﺧﺺ اﮐﻮﻟﻮژﯾﮑﯽ ﺑﻪ ﻣﻨﻈﻮر ﺗﺤﺖ ﻓﺸﺎر ﺑﻮدن ﯾﺎ ﻧﺒﻮدن اﮐﻮﺳﯿﺴﺘﻢ ﻫﺎي ﻣﺮﺗﻌﯽ و ﻣﯿﺰان ﺑﺮﮔﺸـﺖ ﭘـﺬﯾﺮي اﮐﻮﺳﯿﺴـﺘﻢ ﻣﺮﺗﻊ اﺳﺘﻔﺎده ﻧﻤﻮد.
چكيده لاتين :
Knowledge of ecological resilience is needed to understanding the secret of dominant of species in the ecosystems, species migration and the effects of disturbances. Main objective of this study is identifying the most important of ecological resilience in semi-arid mountain rangelands. Study area was Semirom (mountain rangelands, Vank area), located in the south of Isfahan province. The attributes were the share of index species in species composition, vegetation patches, distance between the patches, lichens diversity, soil nitrogen, soil potassium and soil organic carbon. The disturbances were 5 stoking rate (1, 1. 5, 2, 2.5 and 3 animal unit) animal units per hectare, to be studied for 4 years and 5 scenarios (grazing and ungrazing alternatively and consecutively). Data gathered by random sampling in transects and nested sampling units. Statistical analysis (eigenvalue, correlation, regression, beta diversity and simulation) done by the PC-ORD, PAST, and MATLAB softwares. The result showed that the attributes of the share of index species in species composition, soil organic carbon, vegetation patches and of lichens diversity indicates the amount of pressure on ecosystems and ecological resilience well. This attributes can be use in rangeland management as ecological indicators in inventory of under-pressure rangeland and ecosystem resilience.& nbsp; & nbsp
