برآورد زي‌توده، ذخيره كربن و شاخص سطح برگ گونه ارغوان (Cercis siliquastrum L.) در ذخيره گاه جنگلي ارغوان ايلام

Estimation of leaf biomass, leaf carbon sequestration and leaf area index of Cercis siliquastrum L. in forest reserve, Ilam

درﺧﺘﺎن ﺟﻨﮕﻞ، از ﻣﻬﻢﺗﺮﻳﻦ و ﺑﺰرگﺗﺮﻳﻦ ﻣﺨﺎزن ﻛﺮﺑﻦ در اﻛﻮﺳﻴﺴﺘﻢﻫﺎي ﺟﻨﮕﻠﻲ ﺑﺸﻤﺎر ﻣﻲروﻧﺪ و ﺗﺄﺛﻴﺮ ﺑﺴﻴﺎر زﻳﺎدي در ﻛﺎﻫﺶ اﻧﺘﺸﺎر ﻛﺮﺑﻦ اﺗﻤﺴﻔﺮي دارﻧﺪ. از اﻳﻦرو، ﭼﮕﻮﻧﮕﻲ اﻧﺪازهﮔﻴﺮي و ﺑﺮآورد ﻣﻮﺟﻮدي ذﺧﺎﻳﺮ ﻛﺮﺑﻦ درﺧﺘﺎن ﺟﻨﮕﻠﻲ از ﻣﻬﻢ ﺗﺮﻳﻦ ﻣﻮﺿﻮعﻫﺎي ﭘﮋوﻫﺸﻲ ﻣﺤﻘﻘﺎن اﻛﻮﻟﻮژي اﺳﺖ. ﻫﺪف از اﻳﻦ ﺗﺤﻘﻴﻖ، ﺑﺮآورد زيﺗﻮده ﺑﺮگ، ذﺧﻴﺮه ﻛﺮﺑﻦ ﺑﺮگ و ﺷﺎﺧﺺ ﺳﻄﺢ ﺑﺮگ ﮔﻮﻧﻪ ارﻏﻮان )Cercis siliquastrum L.( در ذﺧﻴﺮهﮔﺎه ﺟﻨﮕﻠﻲ ارﻏﻮان اﺳﺘﺎن اﻳﻼم ﺑﻮد. ﺑﺪﻳﻦ ﻣﻨﻈﻮر و ﺑﺎ اﺳﺘﻔﺎده از روش ﻧﻤﻮﻧﻪ- ﺑﺮداري ﺗﺼﺎدﻓﻲ، 30 اﺻﻠﻪ درﺧﺖ ارﻏﻮان اﻧﺘﺨﺎب و ﻣﺘﻐﻴﺮﻫﺎي ارﺗﻔﺎع درﺧﺖ، ﻣﺘﻮﺳﻂ ﻗﻄﺮ ﺗﺎج، ﺗﻌﺪاد ﺟﺴﺖ و ارﺗﻔﺎع ﺗﺎج اﻧﺪازه-ﮔﻴﺮي ﺷﺪ. ﺳﭙﺲ ﺑﺮگﻫﺎي ﻳﻚ ﭼﻬﺎرم ﺗﺎج درﺧﺘﺎن ﻧﻤﻮﻧﻪ ﺟﻤﻊآوري ﺷﺪ. ﭘﺲ از ﺧﺸﻚ ﻛﺮدن در داﺧﻞ آون، وزن ﺧﺸﻚ ﺑﺮگﻫﺎ ﺗﻌﻴﻴﻦ ﺷﺪ. ﭘﺲ از ﺳﻮزاﻧﺪن ﻣﻘﺪار ﻛﺎﻓﻲ از ﺑﺮگﻫﺎي ﺧﺸﻚ ﺷﺪه در ﻛﻮره اﻟﻜﺘﺮﻳﻜﻲ، وزن ﻣﻮاد آﻟﻲ و ﻣﻘﺪار ﻛﺮﺑﻦ ﺑﺮگﻫﺎ ﺑﺪﺳﺖ آﻣﺪ. ﺑﺮاي ﻣﺤﺎﺳﺒﻪ ﺷﺎﺧﺺ ﺳﻄﺢ ﺑﺮگ از روش وزﻧﻲ اﺳﺘﻔﺎده ﺷﺪ. ﻫﻤﭽﻨﻴﻦ ﺑﺮاي ﺗﻌﻤﻴﻢ ﻧﺘﺎﻳﺞ ﺑﺪﺳﺖ آﻣﺪه از درﺧﺘﺎن ﻧﻤﻮﻧﻪ ﺑﻪ ﻛﻞ ﺟﻨﮕﻞ از روش درﺧﺖ ﻣﺘﻮﺳﻂ اﺳﺘﻔﺎده ﺷﺪ. ﻧﺘﺎﻳﺞ ﻧﺸﺎن داد ﻛﻪ ﻣﺘﻮﺳﻂ زيﺗﻮده ﺑﺮگ، ﻣﺘﻮﺳﻂ ذﺧﻴﺮه ﻛﺮﺑﻦ ﺑﺮگ و ﻣﺘﻮﺳﻂ ﻣﻘﺪار ﺟﺬب دي اﻛﺴﻴﺪ ﻛﺮﺑﻦ از ﺟﻮ ﺑﻪ ﺗﺮﺗﻴﺐ 53/55، 23/4 و 86/02 ﻛﻴﻠﻮﮔﺮم در ﻫﻜﺘﺎر ﺑﺪﺳﺖ آﻣﺪ. ﻣﺘﻮﺳﻂ ﺷﺎﺧﺺ ﺳﻄﺢ ﺑﺮگ ﮔﻮﻧﻪ ارﻏﻮان در ﻣﻨﻄﻘﻪ 0/058 ﺑﺪﺳﺖ آﻣﺪ. ﻧﺘﺎﻳﺞ ﺑﺮرﺳﻲ رواﺑﻂ آﻟﻮﻣﺘﺮﻳﻚ ﺑﺎ اﺳﺘﻔﺎده از رواﺑﻂ رﮔﺮﺳﻴﻮﻧﻲ ﺧﻄﻲ ﻧﺸﺎن داد ﻛﻪ ﻫﻤﺒﺴﺘﮕﻲ ﻣﺜﺒﺖ و ﻣﻌﻨﻲداري ﺑﻴﻦ ﻣﺘﻐﻴﺮ ﻣﺘﻮﺳﻂ ﻗﻄﺮ ﺗﺎج ﺑﺎ ﻣﺘﻐﻴﺮﻫﺎي زيﺗﻮده، ذﺧﻴﺮه ﻛﺮﺑﻦ و ﺷﺎﺧﺺ ﺳﻄﺢ ﺑﺮگ درﺧﺘﺎن ارﻏﻮان در ﺟﻨﮕﻞ ﻫﺎي اﻳﻼم وﺟﻮد دارد.

Forest trees are considered as most important and huge carbon pools in the forest ecosystems and have a great influence on the reduction of carbon emission in the atmosphere. Therefore, how to measure and estimate the carbon stored in the trees in the forests are the main issue for ecologists. The aim of this study was to estimate of leaf biomass and leaf carbon sequestration of Cercis siliquastrum L. in Arghavan forests reserves of Ilam. For this purpose, 30 trees were selected using random sampling method and height, mean diameter of crown, number of sprout and crown length variables were measured. All leaves of 1/4 crown area were collected. After of drying, dry weighted of leaves calculated. Enough quantity of leaves (1 gr samples) was burned in electrical kiln to calculate the carbon storage. To calculate of leaf area index was used gravimetric method. Mean tree method was used to generalize the result to the whole forest. Based on results, mean of leaf biomass, mean of leaf carbon sequestration and mean of atmosphere CO2 absorption were 53.55, 23.4 and 86.02 kg per hectare, respectively. Mean of leaf area index in studied area was 0.058. The results of allometric using of linear regression showed that there was a significant and positive correlation between mean diameter of crown and leaf biomass, carbon sequestration and leaf area index variables in the studird area.