ﺗﺄﺛﯿﺮ وﯾﮋﮔﯽ ﻫﺎي ﺳﺎﺧﺘﺎري ﺟﻨﮕﻞ ﺑﺮ ﺑﺮﺧﯽ ﻣﺸﺨﺼﻪ ﻫﺎي ﻓﯿﺰﯾﮑﯽ و ﺷﯿﻤﯿﺎﯾﯽ ﺧﺎك در ﺗﻮده ﻫﺎي ﺟﻨﮕﻠﯽ اﺳﺘﺎن ﮐﺮدﺳﺘﺎن

The effect of forest structure on some physical and chemical soil properties in the forests stands of Kurdistan province

وﯾﮋﮔﯽ ﻫﺎي ﺳﺎﺧﺘﺎري ﺗﻮده ﻫﺎي ﺟﻨﮕﻠﯽ ﺑﺮ ﺧﺎك ﺟﻨﮕﻞ ﺗﺄﺛﯿﺮ دارد. ﻫﺪف اﯾﻦ ﭘﮋوﻫﺶ ﺑﺮرﺳﯽ ﺗﻐﯿﯿﺮ ﺑﺮﺧﯽ وﯾﮋﮔﯽ ﻫﺎي ﻓﯿﺰﯾﮑـﯽ و ﺷﯿﻤﯿﺎﯾﯽ در روﯾﺸﮕﺎه ﻫﺎي ﺟﻨﮕﻠﯽ ﺑﻠﻮط ﺑﺎ ﺳﺎﺧﺘﺎر ﻣﺘﻔﺎوت در اﺳﺘﺎن ﮐﺮدﺳﺘﺎن ﺑﻮد. ﭼﻬﺎر ﻗﻄﻌﻪ ﻧﻤﻮﻧﮥ ﯾﮏ ﻫﮑﺘـﺎري )ﺑـﺎ اﺑﻌـﺎد 100×100 ﻣﺘﺮ( در روﯾﺸﮕﺎه ﻫﺎي ﺟﻨﮕﻠﯽ ﺑﻠﻮط ﺷﻬﺮﺳﺘﺎن ﻫﺎي ﺑﺎﻧﻪ )دو روﯾﺸﮕﺎه(، ﻣﺮﯾﻮان و ﺳﺮوآﺑﺎد )ﻫﺮ ﮐﺪام ﯾـﮏ روﯾﺸـﮕﺎه( اﻧﺘﺨﺎب و در ﻫﺮ ﻗﻄﻌﻪ ﻧﻤﻮﻧﻪ، وﯾﮋﮔﯽ ﻫﺎي ﮐﻤّﯽ و ﺳﺎﺧﺘﺎري درﺧﺘﺎن در اﯾﻦ روﯾﺸﮕﺎه ﻫﺎ ﺑﺮداﺷﺖ ﺷﺪ. ﺳﭙﺲ در ﻫﺮ ﻗﻄﻌﻪ ﻧﻤﻮﻧﮥ ﯾﮏ ﻫﮑﺘﺎري، ﻫﻔﺖ ﻧﻤﻮﻧﻪ ﺧﺎك از ﻋﻤﻖ 0-10 ﺳﺎﻧﺘﯽ ﻣﺘﺮي ﺑﺮداﺷﺖ )در ﮐﻞ 28 ﻧﻤﻮﻧﻪ( و ﻣﺘﻐﯿﺮﻫـﺎي ﻓﯿﺰﯾﮑـﯽ - ﺷـﯿﻤﯿﺎﯾﯽ آﻧﻬـﺎ اﻧﺪازه ﮔﯿﺮي ﺷﺪ. از آزﻣﻮن ﻫﺎي ﺗﺠﺰﯾﮥ وارﯾﺎﻧﺲ ﯾﮑﻄﺮﻓﻪ و ﻣﻘﺎﯾﺴﮥ ﻣﯿﺎﻧﮕﯿﻦ داﻧﮑﻦ ﺑﻪ ﺗﺮﺗﯿﺐ ﺑﺮاي ﺑﺮرﺳﯽ ﻣﻌﻨﯽ دار ﺑﻮدن اﺧـﺘﻼف وﯾﮋﮔﯽ ﻫﺎي اﻧﺪازه ﮔﯿﺮي ﺷﺪة ﺧﺎك و ﻣﻘﺎﯾﺴﮥ ﻣﯿﺎﻧﮕﯿﻦ داده ﻫﺎ در ﭼﻬﺎر روﯾﺸﮕﺎه ﯾﺎدﺷﺪه اﺳﺘﻔﺎده ﺷﺪ. از ﺗﺤﻠﯿﻞ ﻣﺆﻟﻔﻪ ﻫﺎي اﺻـﻠﯽ ﺑﺮاي ﮔﺮوه ﺑﻨﺪي ﻫﻔﺖ ﻣﺸﺨﺼﮥ ﻓﯿﺰﯾﮑﯽ و ﺷﯿﻤﯿﺎﯾﯽ ﺧﺎك ﺑﻪ ﻋﺎﻣﻞ ﻫﺎي آﻣﺎري اﺻﻠﯽ اﺳﺘﻔﺎده ﺷﺪ. ﻧﺘﺎﯾﺞ آزﻣﻮن ﺗﺠﺰﯾﮥ وارﯾـﺎﻧﺲ ﯾﮑﻄﺮﻓﻪ ﻧﺸﺎن دﻫﻨﺪة اﺧﺘﻼف ﻣﻌﻨﯽ دار وﯾﮋﮔﯽ ﻫﺎي ﻓﯿﺰﯾﮑﯽ و ﺷﯿﻤﯿﺎﯾﯽ ﺧﺎك )ﻏﯿﺮ از ﻧﯿﺘـﺮوژن و ﻫـﺪاﯾﺖ اﻟﮑﺘﺮﯾﮑـﯽ( در ﭼﻬـﺎر روﯾﺸﮕﺎه اﺳﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ روﯾﺸﮕﺎه ﻫﺎي ﺟﻨﮕﻠﯽ ﺑﺎ ﺳﺎﺧﺘﺎر ﺷﺎﺧﻪ زاد ﺟﻮان )ﺑﺎ ﺗﺮاﮐﻢ و درﺻﺪ ﺗﺎج ﭘﻮﺷﺶ ﺑﯿﺸﺘﺮ( ﺳـﺒﺐ اﻓﺰاﯾﺶ ﮐﺮﺑﻦ آﻟﯽ )3/15 درﺻﺪ(، ﭘﺘﺎﺳﯿﻢ ﻗﺎﺑﻞ ﺟﺬب )5/37 ﻣﯿﻠﯽ ﮔﺮم ﺑﺮ ﮐﯿﻠﻮﮔﺮم(، ﻓﺴﻔﺮ ﻗﺎﺑﻞ ﺟﺬب )10/5 ﻣﯿﻠـﯽ ﮔـﺮم ﺑـﺮ ﮐﯿﻠﻮﮔﺮم(، ﻫﺪاﯾﺖ اﻟﮑﺘﺮﯾﮑﯽ )483 دﺳﯽ زﯾﻤﻨﺲ ﺑﺮ ﻣﺘﺮ( و رﻃﻮﺑﺖ وزﻧﯽ ﺧﺎك )9/95 درﺻـﺪ( ﻣـﯽ ﺷـﻮﻧﺪ. ﻧﺘـﺎﯾﺞ ﺗﺤﻠﯿـﻞ ﻣﺆﻟﻔﻪ ﻫﺎي اﺻﻠﯽ ﻧﺸﺎن داد ﮐﻪ ﻣﺆﻟﻔﻪ ﻫﺎي اول و دوم 90/27 درﺻﺪ ﺗﻐﯿﯿﺮات روﯾﺸﮕﺎه ﻫﺎ را در ﺑﺮ ﻣﯽ ﮔﯿﺮﻧـﺪ و ﻣﺆﻟﻔـﮥ اول ﺷـﺎﻣﻞ ﻣﺘﻐﯿﺮﻫﺎي ﻫﺪاﯾﺖ اﻟﮑﺘﺮﯾﮑﯽ و ﭘﺘﺎﺳﯿﻢ و ﻣﺆﻟﻔﮥ دوم ﺷﺎﻣﻞ ﻣﺘﻐﯿﺮﻫﺎي ﻓﺴﻔﺮ، درﺻﺪ ﮐﺮﺑﻦ آﻟﯽ و رﻃﻮﺑﺖ اﺳﺖ. ﺑﺎ ﺗﻮﺟﻪ ﺑـﻪ ﺗـﺄﺛﯿﺮ ﻣﺜﺒﺖ ﺗﻮده ﻫﺎي ﺟﻨﮕﻠﯽ ﺑﺎ ﺳﺎﺧﺘﺎر ﺷﺎﺧﻪ زاد ﺟﻮان )ﻫﻤﺴﺎل و ﻧﺎﻫﻤﺴﺎل( ﺑﺮ ﺧﺎك ﺟﻨﮕﻞ، ﭘﯿﺸﻨﻬﺎد ﻣﯽ ﺷﻮد در ﺗﻮده ﻫﺎي ﺷﺎﺧﻪ زاد ﺑﺎ ﺗﺮاﮐﻢ ﮐﻤﺘﺮ از 150 ﭘﺎﯾﻪ در ﻫﮑﺘﺎر، اﻗﺪام اﺣﯿﺎ و ﺗﻮﺳﻌﻪ ﺟﻨﮕﻞ ﺷﻮد.

Structural properties of forest stand affect forest soil and soil characteristics. The purpose of this study is to investigate the changing of soil physical and chemical properties under different forest structure in Kurdistan province. At first, four one-hectare (with dimensions of 100 × 100 m) plots were selected in Baneh (two stands), Marivan and Sarvabad (one stand) and structural characteristics of stands were determined. Seven soil samples were taken from a depth of 0-10 cm in each site (a total of 28 soil samples) and the physical and chemical were measured. Results of one-way analysis of variance test show a significant difference in most of the physical and chemical properties of soil (except nitrogen and electrical conductivity) in the four stands. The results showed that forest stand with young coppice structure (with higher canopy percentage ) increased organic carbon (3.15%), absorbable potassium (5.37 mg/kg), absorbable phosphorus (10.5 mg/kg), electrical conductivity (483 d s m-1) and soil moisture content (9.95%) in compere of another site. The results of principal component analysis showed that the first and second components account for 90.27% of site changes and the first component includes electrical conductivity and potassium variables and the second component includes absorbable phosphorus, organic carbon and weight moisture. Considering the positive effect of forest stand with young coppice structure (with higher canopy percentage and higher tree density) on the forest soil, it is recommended to regenerate and develop the forest in coppice stands with a density of less than 150 tree in hectare.