تنوع ﮔﻮﻧﻪ ﻫﺎي درﺧﺘﯽ و ﺷﺮاﯾﻂ ﺗﺎج و ﺗﻨﮥ درﺧﺖ ﺑﻪ ﻋﻨﻮان ﺷﺎﺧﺺ ﻫﺎي ﭘﺎﯾﺶ ﺳﻼﻣﺖ ﺟﻨﮕﻞ در ﺣﻮزة آﺑﺨﯿﺰ ﺟﻨﮕﻠﯽ ﻣﺎﺳﻮﻟﻪ

Tree Diversity and Tree Crown and Stem Conditions as Indicators of Forest Health Monitoring in Masouleh Forest Watershed

اﯾﻦ ﭘﮋوﻫﺶ ﺑﺎ ﻫﺪف ﺗﺠﺰﯾﻪ و ﺗﺤﻠﯿﻞ ﺗﻨﻮع ﮔﻮﻧﻪ ﻫﺎي درﺧﺘﯽ و ﺷﺮاﯾﻂ ﺗﺎج و ﺗﻨﮥ درﺧﺘﺎن ﺑﻪ ﻣﻨﺰﻟﮥ ﺷﺎﺧﺺ ﻫﺎي ﺳﻼﻣﺖ ﺟﻨﮕﻞ در ﺣـﻮز ة آﺑﺨﯿـﺰ ﺟﻨﮕﻠﯽ ﻣﺎﺳﻮﻟﻪ در اﺳﺘﺎن ﮔﯿﻼن اﻧﺠﺎم ﮔﺮﻓﺖ. ﺟﻤﻊ آوري داده ﻫﺎي ﻣﯿﺪاﻧﯽ ﺑﺎ اﺳﺘﻔﺎده از ﻧﻤﻮﻧﻪ ﺑﺮداري ﺧﻮﺷﻪ اي ﺑﺮاﺳﺎس روش ﭘﺎﯾﺶ ﺳـﻼﻣﺖ ﺟﻨﮕﻞ )FHM( ﺻﻮرت ﭘﺬﯾﺮﻓﺖ ﺷﺪ. در ﻣﺠﻤﻮع ﭘﻨﺞ ﺧﻮﺷﻪ ﺷﺎﻣﻞ 20 ﻗﻄﻌﻪ ﻧﻤﻮﻧﻪ در ﺗﻮدة ﺟﻨﮕﻠﯽ راش آﻣﯿﺨﺘﻪ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪ. در داﺧﻞ ﻫﺮ ﺧﻮﺷﻪ ﻣﺸﺨﺼﺎت ﮐﻤﯽ و ﮐﯿﻔﯽ درﺧﺘﺎن ﻣﻮﺟﻮد ﻣﺎﻧﻨﺪ ﻗﻄﺮ ﺑﺮاﺑﺮﺳﯿﻨﻪ، ارﺗﻔﺎع ﮐﻞ، ﻗﻄﺮ ﺗﺎج، درﺻﺪ ﺧﺸﮑﯿﺪﮔﯽ ﺗﺎج و ﮐﯿﻔﯿﺖ ﺗﻨﮥ درﺧﺘـﺎن ﺑﺮرﺳﯽ و اﻧﺪازه ﮔﯿﺮي ﺷﺪ. ﺑﺮاي ارزﯾﺎﺑﯽ ﺗﻨﻮع ﮔﻮﻧﻪ ﻫﺎي درﺧﺘﯽ، ﺷﺎﺧﺺ ﻫﺎي ﺗﻨﻮع، ﯾﮑﻨﻮاﺧﺘﯽ و ﻏﻨﺎي ﮔﻮﻧﻪ اي در ﻫـﺮ ﺧﻮﺷـﻪ ﻣﺤﺎﺳـﺒﻪ ﺷـﺪ . ﺑﺮاﺳﺎس ﻧﺘﯿﺠﮥ ﺗﺠﺰﯾﻪ وارﯾﺎﻧﺲ، در ﺳﻄﺢ اﺣﺘﻤﺎل 95 درﺻﺪ اﺧﺘﻼف ﻣﻌﻨﯽ داري در ﺑﯿﻦ ﺷﺎﺧﺺ ﻫﺎي ﻣﺬﮐﻮر در ﺧﻮﺷﻪ ﻫﺎي اﻧﺪازه ﮔﯿـ ﺮي ﺷـﺪه ﻣﺸﺎﻫﺪه ﻧﺸﺪ )0/05>P(. ﺑﯿﺸﺘﺮﯾﻦ ﺗﻨﻮع ﮔﻮﻧﻪ ﻫﺎي درﺧﺘﯽ در ﺧﻮﺷﮥ 2 و ﮐﻤﺘﺮﯾﻦ آن در ﺧﻮﺷﮥ 3 ﺑﻪ دﺳﺖ آﻣﺪ. ﺑﯿﺸﺘﺮﯾﻦ ﺗﻐﯿﯿـﺮات در ﺗﻨـﻮع ﮔﻮﻧﻪ ﻫﺎي درﺧﺘﯽ در ﺧﻮﺷﮥ 4 ﻣﺸﺎﻫﺪه ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن ﻣﯽ دﻫﺪ ﮐﻪ ﻫﻤﮥ ﺧﻮﺷﻪ ﻫﺎ در ﻣﻨﻄﻘﮥ ﭘﮋوﻫﺶ از ﻧﻈﺮ ﺷﺎﺧﺺ ﺗﻨﻮع ﮔﻮﻧﻪ ﻫﺎي درﺧﺘـﯽ ﺷﺮاﯾﻂ ﺧﻮﺑﯽ دارﻧﺪ. ﻣﻘﺪار ﺧﺸﮑﯿﺪﮔﯽ ﺗﺎج درﺧﺘﺎن در ﺑﺮﺧﯽ ﮔﻮﻧﻪ ﻫﺎ ﻣﺘﻨﺎﺳﺐ ﺑﺎ روﻧﺪ ﺗﻐﯿﯿﺮات ﻗﻄﺮ ﺗﺎج ﺑﻮد و ﮔﻮﻧﻪ ﻫـ ﺎي درﺧﺘـﯽ ﺷﻤﺸـﺎد و ﺧﺮﻣﻨﺪي ﺑﯿﺸﺘﺮﯾﻦ درﺻﺪ ﺧﺸﮑﯿﺪﮔﯽ ﺗﺎج )در ﺣﺪود 17 درﺻﺪ( را ﺑﻪ ﺧﻮد اﺧﺘﺼﺎص دادﻧﺪ. در ﺧﺼﻮص ﮐﯿﻔﯿﺖ ﺗﻨﮥ درﺧﺘﺎن ﻧﯿﺰ ﺑﯿﺶ از 80 درﺻﺪ درﺧﺘﺎن در اﯾﻦ ﺗﻮدة ﺟﻨﮕﻠﯽ داراي درﺟﮥ ﮐﯿﻔﯽ ﺧﻮب ﻫﺴـﺘﻨﺪ. ﻧﺘﯿﺠـﻪ ﮔﯿـ ﺮي ﻧﻬـﺎﯾﯽ آن اﺳـﺖ ﮐـﻪ وﺿـﻌﯿﺖ ﺳـﻼﻣﺖ ﺑـﻮم ﺳـﺎزﮔﺎن ﺑﺮرﺳﯽ ﺷﺪه از ﻧﻈﺮ ﺳﻄﺢ ﺗﻨﻮع ﮔﻮﻧﻪ ﻫﺎي درﺧﺘﯽ و ﺷﺮاﯾﻂ ﺗﺎج و ﺗﻨﮥ درﺧﺖ ﻣﻄﻠﻮب اﺳﺖ.

This study aimed to analyze tree diversity and tree crown and stem condition as two indicators of forest health in the Masouleh forest watershed, Guilan province. Field data collection was performed using cluster sampling based on Forest Health Monitoring (FHM) method. A total of 5 clusters including 20 subplots in the mixed beech (Fagus orientalis Lipsky.) forest stand were established. Within each cluster, quantitative and qualitative characteristics of existing trees such as diameter at breast height (dbh), total height, canopy diameter, density, and percentage of crown dieback and stem quality were studied and measured. To assess the tree species diversity, species biodiversity indices, richness and evenness were calculated in each cluster. Based on the results of the analysis of variance in 95% confidence level, there are no significant differences in the species diversity indices between the five different clusters (P>0.05). The highest and lowest value of the species diversity indices were measured in clusters 2 and 3, respectively. The largest change in the species diversity occurred at cluster 4. The results showed that all clusters in the study area had good status in terms of the species diversity indices. The amount of canopy drought in some species was proportional to the trend of canopy diameter changes and Buxus hyrcana Pojark. and Diospyros lotus L. species had the highest percentage of canopy drought (approximately 17%). Regarding the quality of stems, more than 80% of the trees in the forest stand have good quality. It is concluded that the health status of the studied ecosystem in terms of the level of tree diversity and tree crown and stem conditions is desirable.