اثر تغيير سيستم آبياري از روش سطحي (غرقابي) به زيرسطحي با لوله هاي پي وي سي (PVC) بر شوري خاك، رشد و عملكرد درختان پسته

Effect of changing irrigation system from surface (flooding) to subsurface method with PVC pipes on soil salinity, growth and yield of pistachio trees

در اﯾﻦ ﭘﺮوژه، اﻣﮑﺎن ﺗﻐﯿﯿﺮ ﺳــﯿﺴــﺘﻢ آﺑﯿﺎري از روش ﻏﺮﻗﺎﺑﯽ ﺑﻪ زﯾﺮﺳــﻄﺤﯽ ﮐﻢﻓﺸــﺎر )ﺑﺎ ﻟﻮﻟﻪﻫﺎي ﭘﯽويﺳــﯽ ﺳﻮراﺧﺪار ( روي درﺧﺘﺎن ﺑﺎرور ﭘﺴﺘﻪ ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﻗﺮار ﮔﺮﻓﺖ. اﯾﻦ ﭘﮋوﻫﺶ در ﻗﺎﻟﺐ ﻃﺮح آﻣﺎري ﺑﻠﻮكﻫﺎي ﮐﺎﻣﻞ ﺗﺼﺎدﻓﯽ ﺑﺎ 3 ﺗﯿﻤﺎر در 3 ﺗﮑﺮار اﻧﺠﺎم ﺷﺪ. ﺗﯿﻤﺎرﻫﺎي آزﻣﺎﯾ ﺸﯽ ﺷﺎﻣﻞ ﺗﯿﻤﺎر ﺷﺎﻫﺪ ) S(، آﺑﯿﺎري ﺑﻪ روش ﻏﺮﻗﺎﺑﯽ ﺑﺎ دور آﺑﯿﺎري 48 روز و ﺣﺠﻢ آب 6720 ﻣﺘﺮ ﻣﮑﻌﺐ در ﻫﮑﺘﺎر، ﺗﯿﻤﺎر P1، آﺑﯿﺎري زﯾﺮﺳـــﻄﺤﯽ ﺑﺎ ﻟﻮﻟﻪ ﻫﺎي ﭘﯽ ويﺳـــﯽ ﺑﺎ ﻣﻘﺪار آب ﻣﻮرد اﺳــﺘﻔﺎده ﺑﺮاي ﺗﯿﻤﺎر ﺷــﺎﻫﺪ و دور آﺑﯿﺎري 12 روز و ﺗﯿﻤﺎر P2، آﺑﯿﺎري زﯾﺮﺳــﻄﺤﯽ ﺑﺎ ﻟﻮﻟﻪﻫﺎي ﭘﯽويﺳــﯽ ﺑﺎ ﻣﻘﺪار آب 75 در ﺻﺪ ﻣﻘﺪار آب ﻣﻮرد ا ﺳﺘﻔﺎده ﺑﺮاي ﺗﯿﻤﺎر ﺷﺎﻫﺪ و دور آﺑﯿﺎري 24 روز ﺑﻮدﻧﺪ. ﻧﺘﺎﯾﺞ ﻧ ﺸﺎن داد ﮐﻪ از ﺑﯿﻦ ﺻﻔﺎت روﯾ ﺸﯽ، ﺳﻄﺢ ﺑﺮگ، ﺗﻌﺪاد ﮐﻞ ﺟﻮاﻧﻪ ﻫﺎ، در ﺻﺪ ﺟﻮاﻧﻪ رﯾﺰش ﮐﺮده و در ﺻﺪ ﺟﻮاﻧﻪ روﯾ ﺸﯽ ﺑﻄﻮر ﻣﻌﻨﯽداري ﺗﺤﺖ ﺗﺎﺛﯿﺮ ﺗﻐﯿﯿﺮ روش آﺑﯿﺎري ﻗﺮار ﮔﺮﻓﺘﻨﺪ. ﻫﻤﭽﻨﯿﻦ ﺗﻐﯿﯿﺮ روش آﺑﯿﺎري ﺑﺮ روي اﻏﻠﺐ ﺻــﻔﺎت ﮐﻤﯽ و ﮐﯿﻔﯽ ﻣﺤﺼــﻮل در ﺳــﻄﺢ 5 درﺻــﺪ اﺛﺮ ﻣﻌﻨﯽدار داﺷــﺖ، ﺑﻪﻃﻮرﯾﮑﻪ ﺑﺎﻋﺚ اﻓﺰاﯾﺶ 0/8 ﺗﺎ 1/6 ﮐﯿﻠﻮﮔﺮﻣﯽ وزن ﻣﺤﺼــﻮل ﺧﺸــﮏ ﻫﺮ درﺧﺖ، ﮐﺎﻫﺶ 1/7 ﺗﺎ 4/25 درﺻﺪي ﭘﻮﮐﯽ، اﻓﺰاﯾﺶ 3/5 ﺗﺎ 6 درﺻﺪي ﺧﻨﺪاﻧﯽ و ﮐﺎﻫﺶ 1/3 ﺗﺎ 2 واﺣﺪي در اﻧﺲ ﭘﺴﺘﻪ ﮔﺮدﯾﺪ . ﺿﻤﻦ اﯾﻨﮑﻪ ﺑﻬﺮه وري ﻣﺼــﺮف آب ﻧﯿﺰ در روش ﻫﺎي آﺑﯿﺎري P1 و P2، ﺑﻪ ﺗﺮﺗﯿﺐ 41/4 درﺻــﺪ و 61/6 درﺻــﺪ اﻓﺰاﯾﺶ ﯾﺎﻓﺖ. ﺗﯿﻤﺎرﻫﺎي آﺑﯿﺎري زﯾﺮﺳﻄﺤﯽ ﺑﺎ ﻟﻮﻟﻪ ﻫﺎي ﭘﯽويﺳﯽ در اﻏﻠﺐ ﺻﻔﺎت ﻣﻮرد ﺑﺮرﺳﯽ، ﺑﺎ ﯾﮑﺪﯾﮕﺮ اﺧﺘﻼف ﻣﻌﻨﯽدار در ﺳﻄﺢ 5 درﺻﺪ ﻧﺪاﺷﺘﻨﺪ. ﻧﺘﺎﯾﺞ ﺷﻮري ﺧﺎك ﻧﺎﺣﯿﻪ رﯾﺸﻪ درﺧﺘﺎن در ﻓﺼﻞ ﭘﺎﯾﯿﺰ )ﻗﺒﻞ از آﺑﺸﻮﯾﯽ( ﻧﯿﺰ ﺣﺎﮐﯽ از اﻓﺰاﯾﺶ ﺷﻮري ﺳﻄﺢ ﺧﺎك در ﻧﺎﺣﯿﻪ ﺑﺎﻻي ﻟﻮﻟﻪﻫﺎي زﯾﺮﺳـﻄﺤﯽ ﺑﻮد. اﻣﺎ ﺷـﻮري ﺧﺎك در اﺳـﻔﻨﺪﻣﺎه و ﭘﺲ از اﻧﺠﺎم آﺑﺸـﻮﯾﯽ و ﺑﺎرﻧﺪﮔﯽ زﻣﺴـﺘﺎﻧﻪ ﺑﻪ وﺿـﻌﯿﺘ ﯽ ﻣﻨﺎﺳــﺐ )ﮐﻤﺘﺮ از dS/m 9( رﺳــﯿﺪ. ارزﯾﺎﺑﯽ اﻗﺘﺼــﺎدي اﺟﺮاي اﯾﻦ ﭘﺮوژه ﻧﯿﺰ ﺣﺎﮐﯽ از ﺗﻮﺟﯿﻪ اﻗﺘﺼــﺎدي ﺑﺎﻻي آن دارد، ﺑﻪﻃﻮرﯾﮑﻪ ﺑﺎ ﺳــﺮﻣﺎﯾﻪﮔﺬاري ﺳــﺎﻟﯿﺎﻧﻪ در ﺣﺪود 60 ﻣﯿﻠﯿﻮن رﯾﺎل در ﻫﺮ ﻫﮑﺘﺎر )ﺑﻪ ﻋﻨﻮان ﺳــﺮﻣﺎﯾﻪﮔﺬاري اوﻟﯿﻪ( ﺑﺮاي ﺗﻐﯿﯿﺮ ﺳﯿ ﺴﺘﻢ، ﺑ ﺴﺘﻪ ﺑﻪ اﻧﺘﺨﺎب روش آﺑﯿﺎري P1 ﯾﺎ P2، ﺑﻪ ﺗﺮﺗﯿﺐ درآﻣﺪي ﻣﻌﺎدل 7/6 و 15/2 ﺑﺮاﺑﺮ ﺳﺮﻣﺎﯾﻪ ﮔﺬاري اوﻟﯿﻪ، ﻋﺎﯾﺪ ﺑﺎﻏﺪار ﺧﻮاﻫﺪ ﺷﺪ. ﺑﻨﺎﺑﺮاﯾﻦ ﺑﺎ در ﻧﻈﺮ ﮔﺮﻓﺘﻦ ﻣﺤﺪودﯾﺖﻫﺎي ﻣﻨﺎﻃﻖ ﭘﺴﺘﻪﮐﺎري اﯾﺮان از ﻧﻈﺮ ﮐﻤﯿﺖ و ﮐﯿﻔﯿﺖ ﻣﻨﺎﺑﻊ آب در دﺳﺘﺮس، اﺳﺘﻔﺎده از روش P2 ﺑﻪ دﻟﯿﻞ ﮐﺎﻫﺶ 25 درﺻﺪي ﻣﺼﺮف آب و اﻓﺰاﯾﺶ 61/6 و 14/3 درﺻﺪي ﺑﻬﺮه وري ﻣﺼﺮف آب، ﺑﻪ ﺗﺮﺗﯿﺐ ﻧﺴﺒﺖ ﺑﻪ روشﻫﺎي S و P1، ﻗﺎﺑﻞ ﺗﻮﺻﯿﻪ ﻣﯽﺑﺎﺷﺪ.

In this project, the possibilities of changing the method of surface irrigation (flooding) to subsurface irrigation system (with porous PVC tubes) were studied on mature pistachio trees. This research was conducted as a randomized complete block design with three treatments and three replications. Treatments included: control (S) by flood irrigation with 48 days irrigation frequency and the volume of 6720 cubic meters per hectare, P1 treatment, subsurface irrigation with PVC pipes with the amount of water used for irrigation control(S) and 12 days irrigation frequency and, P2 treatment, subsurface irrigation with PVC pipes with a water content of 75% of the water used to control and 24 days irrigation frequency. The results showed that among the growth characteristics, leaf area, total number of buds, percentage of fallen bud and vegetative bud were significantly affected by changes in irrigation methods. But changing irrigation methods on the most of quantitative and qualitative factors, significant effect at 5% level, as, increased the dry product from 0.8 to 1.6 Kg per tree, reduced blanking from 1.7 to 4.25 percent, increased splitting from 3.5 to 6 percent and reduced the number of nuts per ounce of pistachios from 1.3 to 2 units. While the WUP in irrigation methods of P1 and P2, increased 41.4% and 61.6%, respectively. There were no significant differences (P≤ 0.05) in subsurface irrigation treatments in most traits. The results of soil salinity in the root zone of trees in autumn (before leaching) also showed an increase in soil salinity in the soil surface and above the subsurface pipes. But, soil salinity after leaching and precipitation in the winter was appropriately (Less than 9 dS/m). Economic evaluation of this project showed that high economic justification. So, with an annual investment of about 60 million rials (as an initial investments) in Hectare to change the system, depending on the choice of irrigation method P1 or P2, respectively, earning between 7.6 to 15.2 times the initial investments, growers will receive. Therefore, considering the limitations of the pistachio producing regions in Iran, In terms of quantity and quality of available water resources, P2 method, due to a 25 percent reduction in water consumption and increasing 61.6% and 14.3% in WUP, respectively, compared to methods S and P1, is advisable.