نقش برش هاي بهداشتي در كنترل خشكيدگي بلوط ايراني (مطالعه موردي: فاز دوم، زاگرس، ايلام، مله سياه)

The role of sanitary cuts in control of Persian oak dieback) Case study, second phase, Zagros, Ilam, Melah Siah)

ﺳﺎﺑﻘﻪ و ﻫﺪف: ﺣﻮزه روﯾﺸﯽ ﻧﯿﻤﻪ ﺧﺸﮏ زاﮔﺮس ﺑﻪ ﻋﻨﻮان دوﻣﯿﻦ ﻣﻨﺒﻊ زيﺗﻮده ﺟﻨﮕﻠﯽ اﯾﺮان اﻫﻤﯿﺖ زﯾﺴﺖ ﻣﺤﯿﻄﯽ وﯾﮋه اي دارد. در ﻃﻮل دﻫﻪﻫﺎي ﮔﺬﺷﺘﻪ ﺗﻮان ﺑﻮمﺷﻨﺎﺧﺘﯽ اﯾﻦ ﻣﻨﻄﻘﻪ در اﺛﺮ ﻓﺸﺎر ﺷﺪﯾﺪ اﻧﺴﺎن ﺿﻌﯿﻒ ﺷﺪه و درﺧﺘﺎن ﺟﻨﮕﻠﯽ آن ﻧﯿﺰ در دو دﻫﻪ اﺧﯿﺮ ﺗﺤﺖ ﺗﺄﺛﯿﺮ اﺳﺘﺮس ﺧﺸﮑﺴﺎﻟﯽ و ﺣﻤﻠﻪ آﻓﺎت ﭼﻮب ﺧﻮار و ﻗﺎرچ ذﻏﺎﻟﯽ در ﺣﺎل زوال ﻣﯽ ﺑﺎﺷﻨﺪ. ازآﻧﺠﺎﮐﻪ ﻣﺒﺎرزه ﺷﯿﻤﯿﺎﯾﯽ در ﺑﻮمﺳﺎزﮔﺎنﻫﺎ ﺷﺮاﯾﻂ ﻃﺒﯿﻌﯽ را ﺑﯿﺶ ﺗﺮ دﭼﺎر اﺧﺘﻼل ﮐﺮده و ﻣﺒﺎرزه ﺑﯿﻮﻟﻮژﯾﮏ ﻧﯿﺰ ﻧﯿﺎزﻣﻨﺪ اﺟﺮاي ﺗﺤﻘﯿﻘﺎت ﻃﻮﻻﻧﯽ ﻣﺪت اﺳﺖ، ﺑﻨﺎﺑﺮاﯾﻦ در ﺷﺮاﯾﻂ ﺣﺎل، اﻋﻤﺎل ﺑﺮش ﻫﺎي ﺑﻬﺪاﺷﺘﯽ ﻣﻬﻢ ﺗﺮﯾﻦ راﻫﮑﺎر ﮐﻨﺘﺮل زوال ﺟﻨﮕﻞ ﻫﺎي زاﮔﺮس ﻣﺤﺴﻮب ﻣﯽﺷﻮد. در ﻣﻨﺎﺑﻊ ﻋﻠﻤﯽ ﻣﺘﻌﺪد، ﻧﻘﺶ ﻣﺜﺒﺖ ﺳﺮﺷﺎﺧﻪزﻧﯽ و ﻫﺮس درﺧﺘﺎن در ﮐﻨﺘﺮل آﻓﺎت و اﻣﺮاض ﮔﺰارش ﺷﺪه اﺳﺖ. اﯾﻦ ﻣﻘﺎﻟﻪ، ﻧﺘﺎﯾﺞ ﻓﺎز دوم ﭘﮋوﻫﺸﯽ اﺳﺖ ﮐﻪ ﺑﻪ ﺑﺮرﺳﯽ ﺷﯿﻮه ﻣﻨﺎﺳﺐ ﺑﺮش ﺑﻬﺪاﺷﺘﯽ در ﺟﻨﮕﻞﻫﺎي ﺣﻮزه روﯾﺸﯽ زاﮔﺮس در دوره ﭼﻬﺎر ﺳﺎﻟﻪ دوم ﭘﺮداﺧﺘﻪ اﺳﺖ. ﻫﺪف ﺑﺮرﺳﯽ ﻧﻘﺶ ﭘﻨﺞ ﺗﯿﻤﺎر ﻗﻄﻊ و ﺷﺎﺧﻪ زﻧﯽ در دو ﻓﺮم داﻧﻪزاد و ﺷﺎﺧﻪ زاد ﺑﺮاي ﮐﻨﺘﺮل ﺧﺸﮑﯿﺪﮔﯽ درﺧﺘﺎن ﺑﻠﻮط اﯾﺮاﻧﯽ ﻧﺎﺣﯿﻪ روﯾﺸﯽ زاﮔﺮس ﺑﻮد. ﻣﻮاد و روش ﻫﺎ: در اﺟﺮاي اﯾﻦ ﭘﮋوﻫﺶ، ﺗﺄﺛﯿﺮ ﻓﺮم روﯾﺸﯽ و ﺑﺮشﻫﺎي ﺑﻬﺪاﺷﺘﯽ در درﺻﺪ زﻧﺪهﻣﺎﻧﯽ و ﺷﺎداﺑﯽ درﺧﺘﺎن ﺑﻠﻮط اﯾﺮاﻧﯽ، ﭘﺲ از ﮔﺬﺷﺖ ﻫﺸﺖ ﺳﺎل ﻣﻮرد آزﻣﻮن ﻗﺮار ﮔﺮﻓﺘﻪ و ﺑﺎ ﻧﺘﺎﯾﺞ ﻓﺎز اول ﭘﺮوژه در دوره ﭼﻬﺎر ﺳﺎﻟﻪ ﻓﺎز اول ﻣﻘﺎﯾﺴﻪ ﺷﺪ. ﻓﺮم روﯾﺸﯽ در دو ﺳﻄﺢ داﻧﻪزاد و ﺷﺎﺧﻪزاد و ﻧﻮع ﺑﺮش ﺑﻬﺪاﺷﺘﯽ در ﭘﻨﺞ ﺳﻄﺢ، ﺷﺎﻣﻞ ﺣﺬف ﻗﻄﻌﺎت آﻟﻮده، ﺣﺬف ﮐﺎﻣﻞ ﺗﺎج، ﻗﻄﻊ در ارﺗﻔﺎع 10 ﺳﺎﻧﺘﯽﻣﺘﺮي ﺗﻨﻪ ﯾﺎ ﺟﺴﺖ، ﻗﻄﻊ در ﻋﻤﻖ 10 ﺳﺎﻧﺘﯽﻣﺘﺮي ﺗﻨﻪ ﯾﺎ ﺟﺴﺖ و ﺗﯿﻤﺎر ﺷﺎﻫﺪ )ﻓﺎﻗﺪ ﺑﺮش ﭘﺮورﺷﯽ( ﺑﺮرﺳﯽ ﺷﺪ. در ﻣﻘﺎﯾﺴﻪ ﺗﯿﻤﺎرﻫﺎي آزﻣﺎﯾﺶ ﺑﻪ دﻟﯿﻞ ﮐﯿﻔﯽ ﺑﻮدن دادهﻫﺎي ﻣﺘﻐﯿﺮ ﺷﺎداﺑﯽ و ﻓﻘﺪان ﭘﯿﺶ ﻓﺮض ﻫﺎي آﻣﺎر ﭘﺎراﻣﺘﺮي در ﺗﯿﻤﺎرﻫﺎي زﻧﺪه ﻣﺎﻧﯽ از آزﻣﻮن ﻫﺎي ﻧﺎﭘﺎراﻣﺘﺮي اﺳﺘﻔﺎده ﺷﺪ. ﺟﻔﺖ ﺗﯿﻤﺎرﻫﺎي دو ﻓﺎز ﭘﮋوﻫﺶ ﺑﺎ آزﻣﻮن وﯾﻠﮑﺎﮐﺴﻮن )Wilcoxon(، دو ﺗﯿﻤﺎر ﻓﺮم روﯾﺸﯽ ﺑﺎ آزﻣﻮن ﻣﻦ-وﯾﺘﻨﯽ )Mann-Whitney(، ﺗﯿﻤﺎرﻫﺎي ﺑﺮشﻫﺎي ﺑﻬﺪاﺷﺘﯽ ﺑﻪ ﺻﻮرت ﮔﺮوﻫﯽ ﺑﺎ آزﻣﻮن ﮐﺮوﺳﮑﺎل-واﻟﯿﺲ و ﺑﻪ ﺻﻮرت ﺟﻔﺘﯽ ﺑﺎ آزﻣﻮن دان-ﺑﻦ ﻓﺮوﻧﯽ )Dunn-Bonferroni( ﻣﻘﺎﯾﺴﻪ ﺷﺪﻧﺪ. ﯾﺎﻓﺘﻪ ﻫﺎ: ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ اﺧﺘﻼف زﻧﺪه ﻣﺎﻧﯽ و ﺷﺎداﺑﯽ دو ﻓﺮم روﯾﺸﯽ در دو ﻓﺎز ﭘﮋوﻫﺶ ﻧﺴﺒﺖ ﺑﻪ ﻫﻢ در ﺳﻄﺢ اﺣﺘﻤﺎل 5% ﻣﻌﻨﯽ دار ﻧﺒﻮد. اﺧﺘﻼف زﻧﺪه ﻣﺎﻧﯽ ﺗﯿﻤﺎرﻫﺎي ﺑﺮش ﺑﻬﺪاﺷﺘﯽ در دو ﻓﺎز ﭘﮋوﻫﺶ ﺑﻪ ﺟﺰ در ﺗﯿﻤﺎر ﻗﻄﻊ ﺑﺨﺶ ﻫﺎي آﻟﻮده در ﺳﺎﯾﺮ ﺗﯿﻤﺎرﻫﺎ در ﺳﻄﺢ اﺣﺘﻤﺎل 1% ﻣﻌﻨﯽ دار ﺑﻮد. اﺧﺘﻼف ﺷﺎداﺑﯽ ﺗﯿﻤﺎرﻫﺎي ﺑﺮش در دو ﻓﺎز ﭘﮋوﻫﺶ، ﺑﺮﺧﻼف زﻧﺪه ﻣﺎﻧﯽ ﻓﻘﻂ در ﺗﯿﻤﺎر ﺷﺎﻫﺪ در ﺳﻄﺢ اﺣﺘﻤﺎل 1% ﻣﻌﻨﯽ دار ﺑﻮد. ﻧﺘﺎﯾﺞ زﻧﺪه ﻣﺎﻧﯽ و ﺷﺎداﺑﯽ ﭘﺲ از ﮔﺬﺷﺖ ﻫﺸﺖ ﺳﺎل از ﺷﺮوع آزﻣﺎﯾﺶ در ﻓﺎز دوم، ﺑﯿﺎﻧﮕﺮ ﻣﻌﻨﯽ داري اﺧﺘﻼف )%1 = α( ﺗﯿﻤﺎرﻫﺎي ﺑﺮش و ﻋﺪم ﻣﻌﻨﯽ داري )%5 = α( دو ﺗﯿﻤﺎر ﻓﺮم روﯾﺸﯽ ﺑﻮد. ﻧﺘﺎﯾﺞ ﻣﻘﺎﯾﺴﺎت زوﺟﯽ ﻧﯿﺰ ﻧﺸﺎن داد ﮐﻪ اﺧﺘﻼف درﺻﺪ ﺷﺎداﺑﯽ دو ﺗﯿﻤﺎر ﻗﻄﻊ از ﻋﻤﻖ و از ارﺗﻔﺎع 10 ﺳﺎﻧﺘﯽ ﻣﺘﺮ ﺑﺎ ﺗﯿﻤﺎر ﺷﺎﻫﺪ و اﺧﺘﻼف دو ﺗﯿﻤﺎر ﻗﻄﻊ ﺑﺨﺶ ﻫﺎي آﻟﻮده و ﻗﻄﻊ ﮐﺎﻣﻞ ﺗﺎج ﻧﺴﺒﺖ ﺑﻪ ﻫﻢ ﻣﻌﻨﯽ دار ﻧﺒﻮد )1% = α(. ﻧﺘﯿﺠﻪ ﮔﯿﺮي: در ﻣﺠﻤﻮع، ﺗﯿﻤﺎر ﻗﻄﻊ ﻫﺪﻓﻤﻨﺪ ﺑﺨﺶ ﻫﺎي آﻟﻮده از ﻧﻈﺮ زﻧﺪه ﻣﺎﻧﯽ )88/8%( ﮐﻪ ﻋﺎﻣﻞ اﺻﻠﯽ ﭘﮋوﻫﺶ ﺑﻮد ﺑﻪ ﺗﻨﻬﺎﯾﯽ و از ﻧﻈﺮ ﺷﺎداﺑﯽ )87/4%( ﻫﻤﺮاه ﺑﺎ ﺗﯿﻤﺎر ﻗﻄﻊ ﮐﺎﻣﻞ ﺗﺎج ﺑﻬﺘﺮﯾﻦ ﻧﺘﯿﺠﻪ را در ﺑﯿﻦ ﺗﯿﻤﺎرﻫﺎي ﺑﺮش ﻧﺸﺎن داد؛ ﺑﻨﺎﺑﺮاﯾﻦ، ﻗﻄﻊ ﺑﺨﺶ ﻫﺎي آﻟﻮده ﺑﺮاي ﮐﻨﺘﺮل ﻣﺮگ درﺧﺘﺎن ﺑﻠﻮط اﯾﺮاﻧﯽ در ﻋﺮﺻﻪ ﻫﺎي ﺟﻨﮕﻠﯽ ﻣﺸﺎﺑﻪ در زاﮔﺮس ﺗﻮﺻﯿﻪ ﻣﯽ ﮔﺮدد.

Background and objectives The semi-arid vegetation area of Zagros is the second source of forest biomass in Iran and has a special environmental importance. Over the past decades, the ecological potential of this region has degraded due to severe human pressure, and its forest trees have declined in the last two decades due to drought stress and attacks by wood-eating pests and charcoal fungi. Since chemical control further disturbs the natural conditions in ecosystems and biological control requires long-term research, so the application of sanitary cuttings is the most important way to control the degradation of Zagros forests in the current situation. Numerous scientific references have reported the positive role of branching and pruning of forest and garden trees in controlling pests and diseases. This article is the results of the second phase of a study that investigated the proper method of sanitary cutting in the forests of the Zagros vegetation area in the next four years. The aim was to investigate the role of five cuttings treatments in two forms of high and coppice to control the dieback of Persian Oak trees in the Zagros area. Materials and methods In this study, the effects of vegetative form and sanitary cuttings on the survival and vitality of Persian oak after eight years was tested and compared with the project results in the four-year period of the first phase. Vegetative form was studied at two levels of high and coppice and cutting type in five levels including removal of infected parts of trees, complete removal of crown, cutting from height 10 cm and cutting from 10 cm depth and control treatment (without sanitary cutting). The researches treatments were compared with non-parametric tests due to the quality of the vitality data and the lack of parametric statistics assumptions in the survival treatments. Pair of two-phase research treatments were compared with Wilcoxon test, two vegetative form treatments with Mann-Whitney test and group cutting treatments with Kruskal-Wallis test and in pairs with Dunn-Bonferroni test. Results The results showed that the difference in survival and vitality of the two vegetative forms in the two phases of the study was not significant at the 5% probability level. The difference of survival of cutting treatments in the two phases of the study was significant in all treatments at the level of 1% probability, except in the treatment of cutting infected sections. The difference of viability of cutting treatments in the two phases of the study was significant only in the control treatment at the level of 1% probability, in contrast to survival. The results of survival and vitality after eight years from the start of the experiment in the second phase showed a significant difference (α=1%) in the cutting treatments and no significance (α=5%) in the two vegetative form treatments. Also, the results of pairwise comparisons showed that the difference in the vitality percentage of the two treatments cut from the depth and from a height of 10 cm with the control treatment and the difference between the two treatments of cutting infected parts and complete cutting of the crown were not significant (α=1%). Conclusion In general, the targeted cutting treatment of infected parts in terms of survival (88.8%) which was the main factor of the study showed the best result alone and in terms of vitality (87.4%) with complete crown cutting treatment. Therefore, this sanitary cut is recommended to control the dieback of Persian oak trees in similar forest areas in the Zagros.