ﺑﺮرﺳﯽ ﺗﺄﺛﯿﺮ ﺳﺮﻋﺖ، ﻋﻤﻖ و ﻧﻮع ﺧﺎك ورز ﺑﺮ ﻧﺎﻫﻤﻮاري ﺳﻄﺢ ﺧﺎك و ﻣﯿﺰان زﯾﺮ ﺧﺎك ﺷﺪن ﺑﻘﺎﯾﺎي ﮔﯿﺎﻫﯽ در اراﺿﯽ دﯾﻢ

Investigation of the Effect of Speed, Depth, and Type of Tillage on Soil Surface Roughness and Burial of Plant Residues in Rainfed Lands

ﻧﺎﻫﻤﻮاري و وﺟﻮد ﺑﻘﺎﯾﺎي ﮔﯿﺎﻫﯽ در ﺳﻄﺢ ﺧﺎك ﺑﻪﺧﺼﻮص در اراﺿﯽ دﯾﻢ، ﻣﯽﺗﻮاﻧﺪ ﻣﻮﺟﺐ ﮐﻨﺪ ﺷﺪن روﻧﺪ ﻓﺮﺳﺎﯾﺶ ﺷﻮد. ﻫﺪف از اﯾﻦ ﺗﺤﻘﯿﻖ، اﻧﺘﺨﺎب ﻣﻨﺎﺳﺐﺗﺮﯾﻦ روش ﺧﺎكورزي اﺳﺖ ﮐﻪ ﺑﯿﺸﺘﺮﯾﻦ ﺷﺎﺧﺺ ﻧﺎﻫﻤﻮاري و ﮐﻤﺘﺮﯾﻦ ﻣﯿﺰان دﻓﻦ ﺑﻘﺎﯾﺎي ﮔﯿﺎﻫﯽ را داﺷﺘﻪ ﺑﺎﺷﺪ. آزﻣﺎﯾﺶ ﻫﺎ ﺑﺎ آزﻣﻮن ﻓﺎﮐﺘﻮرﯾﻞ در ﻗﺎﻟﺐ ﻃﺮح ﮐﺎﻣﻼً ﺗﺼﺎدﻓﯽ ﺑﺎ ﺳﻪ ﻋﺎﻣﻞ ﻧﻮع دﺳﺘﮕﺎه ﺧﺎكورز )ﭼﻬﺎر ﺳﻄﺢ ﮔﺎوآﻫﻦ ﺑﺮﮔﺮداندار، ﺑﺮﮔﺮداندار+ دﯾﺴﮏ، ﮔﺎوآﻫﻦ ﺑﺸﻘﺎﺑﯽ و ﺧﺎكورز ﻗﻠﻤﯽ(، ﺳﺮﻋﺖ ﺷﺨﻢزﻧﯽ )ﺳﻪ ﺳﻄﺢ 3، 5و 7ﮐﯿﻠﻮﻣﺘﺮ ﺑﺮ ﺳﺎﻋﺖ( و ﻋﻤﻖ ﺷﺨﻢ )دو ﺳﻄﺢ 15-20و 25-30ﺳﺎﻧﺘﯽﻣﺘﺮ( اﺟﺮا ﺷﺪ. ﻧﺎﻫﻤﻮاري ﺳﻄﺢ ﺧﺎك، ﺑﻪ ﮐﻤﮏ دﺳﺘﮕﺎه ﭘﯿﻦﻣﺘﺮ اﻧﺪازه ﮔﯿﺮي ﺷﺪ. ﺑﺮاي ﺗﻌﯿﯿﻦ درﺻﺪ زﯾﺮ ﺧﺎك ﺷﺪن ﺑﻘﺎﯾﺎي ﮔﯿﺎﻫﯽ، از روش ﭘﺮدازش ﺗﺼﻮﯾﺮ اﺳﺘﻔﺎده ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﺗﺄﺛﯿﺮ ﺗﻤﺎم ﻣﺘﻐﯿﺮﻫﺎي اﺻﻠﯽ ﺑﺮ ﺷﺎﺧﺺ ﻧﺎﻫﻤﻮاري ﺳﻄﺢ ﺧﺎك ﻣﻌﻨﯽدار اﺳﺖ و ﺑﯿﺸﺘﺮﯾﻦ و ﮐﻤﺘﺮﯾﻦ ﺷﺎﺧﺺ ﻧﺎﻫﻤﻮاري ﺑﻪﺗﺮﺗﯿﺐ ﻣﺮﺑﻮط ﺑﻪ ﮔﺎوآﻫﻦ ﺑﺮﮔﺮداندار ) 12 /8ﺳﺎﻧﺘﯽﻣﺘﺮ( و ﺗﺮﮐﯿﺐ ﺑﺮﮔﺮداندار+دﯾﺴﮏ ) 3 /6ﺳﺎﻧﺘﯽﻣﺘﺮ( ﺑﻮد. ﻫﻤﭽﻨﯿﻦ ﮔﺎوآﻫﻦ ﻗﻠﻤﯽ و ﺷﺨﻢ ﺗﺮﮐﯿﺐ ﺑﺮﮔﺮداندار+دﯾﺴﮏ ﺑﻪﺗﺮﺗﯿﺐ ﮐﻤﺘﺮﯾﻦ و ﺑﯿﺸﺘﺮﯾﻦ ﻣﯿﺰان زﯾﺮ ﺧﺎك ﺷﺪن ﺑﻘﺎﯾﺎي ﮔﯿﺎﻫﯽ را ﺑﺎ ﻣﻘﺎدﯾﺮ 29/3و 92 /9درﺻﺪ ﻧﺸﺎن دادﻧﺪ. ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻧﺘﺎﯾﺞ ﻣﯽﺗﻮان ﺧﺎكورز ﻗﻠﻤﯽ را ﺑﻪﻋﻨﻮان ﻣﻨﺎﺳﺐﺗﺮﯾﻦ روش ﺧﺎكورزي از ﻧﻈﺮ ﺣﻔﺎﻇﺖ از ﺧﺎك در ﻣﻘﺎﺑﻞ ﻓﺮﺳﺎﯾﺶ ﺑﺎدي و آﺑﯽ اﻧﺘﺨﺎب ﮐﺮد.

The presence of soil surface roughness and plant residues can slow down the erosion process, particularly on rainfed fields. The aim of this study was to select the most suitable tillage method, which has the highest soil surface roughness index and the lowest rate of the burial of plant residues. Three factors of plowing machine (Moldboard-plow, Moldboard-plow + Disc harrow, Disc plow and Chisel plow), speed (3, 5 and 7 km/h) and tillage depth (15-20 cm and 25-30 cm) were evaluated in a factorial experiment in a completely randomized design. The soil surface roughness was measured using a pin-meter. Image processing techniques were used to determine the percentage of burial of plant residues. The results showed that the effect of all main factors on the soil surface roughness index was significant and the highest and lowest roughness indices were related to moldboard plow (12.8cm) and Moldboard plow+Disc harrow (3.6cm), respectively. In addition, Chisel plows and Disc harrow+Moldboard plow treatment showed the lowest and highest rates of plant residue burial of 29.3% and 92.9%, respectively. Taking into account the results, chisel plow can be selected as the most suitable tillage method in terms of soil protection against wind and water erosion.