كليدواژه :
آب ﺑﺎران , اراﺿﯽ ﺷﯿﺐ دار , ژﺋﻮﻣﻤﺒﺮان , ﺳﻄﺢ ﻋﺎﯾﻖ , ﻣﺎﻟﭻ ﺷﻨﯽ
چكيده فارسي :
اﺳﺘﻔﺎده ﺑﻬﯿﻨﻪ از ﻧﺰوﻻت ﺟﻮي در ﻣﻨﺎﻃﻖ ﺧﺸﮏ و ﻧﯿﻤﻪ ﺧﺸﮏ ﻣﯽ ﺗﻮاﻧﺪ ﻧﻘﺶ ﺑﺴﺰاﯾﯽ در ﺗﺄﻣﯿﻦ ﻧﯿﺎز آﺑﯽ ﻓﻀﺎي ﺳﺒﺰ در ﻓﺼﻮل ﮐﻢ آب داﺷﺘﻪ ﺑﺎﺷﺪ. از ﻃﺮف دﯾﮕﺮ، ﺿﻌﯿﻒ ﺑﻮدن ﭘﻮﺷﺶ ﮔﯿﺎﻫﯽ در اراﺿﯽ ﺷﯿﺐ دار ﺑﺎﻋﺚ ﺗﺨﺮﯾﺐ و ﻓﺮﺳﺎﯾﺶ اﯾﻦ ﮔﻮﻧﻪ اراﺿﯽ ﻣﯽ ﺷﻮد ﮐﻪ در ﺻﻮرت ﻣﺪﯾﺮﯾﺖ ﺻﺤﯿﺢ ﻣﻨﺎﺑﻊ آب و ﺧﺎك ﻣﯽ ﺗﻮان ﺑﺨﺸﯽ از ﻣﺸﮑﻼت ﻣﺬﮐﻮر را ﺑﺮﻃﺮف ﮐﺮد. ﺑﺎرش ﻫﺎي ﺟﻮي از ﻣﻬﻤﺘﺮﯾﻦ ﻣﻨﺎﺑﻊ در ﺗﺄﻣﯿﻦ آب ﺑﺮاي ﻣﺼﺎرف ﻣﺨﺘﻠﻒ ﻫﺴﺘﻨﺪ. ﯾﮑﯽ از روش ﻫﺎي ﺟﻤﻊ آوري آب ﺑﺎران، ﻏﯿﺮﻗﺎﺑﻞ ﻧﻔﻮذ ﮐﺮدن ﺳﻄﺢ زﻣﯿﻦ و ﺑﻪ ﺑﯿﺸﯿﻨﻪ رﺳﺎﻧﺪن رواﻧﺎب ﻧﺎﺷﯽ از ﺑﺎرش اﺳﺖ. ﺳﻄﻮح ﻏﯿﺮﻗﺎﺑﻞ ﻧﻔﻮذ ﻣﯽ ﺗﻮاﻧﻨﺪ ﻣﺎﻧﻨﺪ ﺳﻄﻮح ﺳﻨﮕﯽ ﺑﻪ ﺻﻮرت ﻃﺒﯿﻌﯽ وﺟﻮد داﺷﺘﻪ، ﯾﺎ ﺑﺎ ﭘﻮﺷﺎﻧﺪن ﺳﻄﺢ زﻣﯿﻦ از ﻣﻮادي ﻣﺎﻧﻨﺪ آﺳﻔﺎﻟﺖ، ﺑﺘﻦ، ورﻗﻪ ﻫﺎي ﻋﺎﯾﻖ ﻣﺎﻧﻨﺪ ﭘﻼﺳﺘﯿﮏ، ژﺋﻮﻣﻤﺒﺮان و دﮐﺎﻣﻮﻧﺪ ﺑﻪ ﻃﻮر ﻣﺼﻨﻮﻋﯽ اﯾﺠﺎد ﺷﻮﻧﺪ. اﯾﻦ ﭘﮋوﻫﺶ ﮐﻪ در ﻗﺴﻤﺖ ﺷﻤﺎﻟﯽ ﺷﻬﺮ ﺗﺒﺮﯾﺰ اﺟﺮا ﺷﺪ، ﭼﻬﺎر ﻧﻮع ﺗﯿﻤﺎر، ﻫﺮ ﮐﺪام در ﺳﻪ ﺗﮑﺮار ﺑﻪ ﻣﺴﺎﺣﺖ ﭼﻬﺎر ﻣﺘﺮ ﻣﺮﺑﻊ )2m×2m( در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪﻧﺪ ﮐﻪ ﺷﺎﻣﻞ ﺳﻄﺢ آﺑﮕﯿﺮ ﭘﻮﺷﺶ ژﺋﻮﻣﻤﺒﺮان، ﭘﻮﺷﺶ ﭘﻼﺳﺘﯿﮏ ﺑﺎ ﻣﺤﺎﻓﻆ ﺷﻨﯽ، ﺳﻄﺢ ﻃﺒﯿﻌﯽ و ﺳﻄﺢ ﻃﺒﯿﻌﯽ ﺑﺎ ﻣﺎﻟﭻ ﺷﻨﯽ ﺑﻮدﻧﺪ. ﻧﺘﺎﯾﺞ ﺣﺎﺻﻞ از 78 ﻣﻮرد ﺑﺎرش )747 ﻣﯿﻠﯽ ﻣﺘﺮ( در ﻣﺪت دو ﺳﺎل، ﻧﺸﺎن داد ﮐﻪ در ﺷﯿﺐ ﻫﺎي ﻣﺘﻮﺳﻂ 33-38/6 درﺻﺪ رواﻧﺎب ﺣﺎﺻﻞ از ﺑﺎرش ﺑﺮاي ﭘﻮﺷﺶ ژﺋﻮﻣﻤﺒﺮان، ﭘﻼﺳﺘﯿﮏ ﺑﺎ ﻣﺤﺎﻓﻆ ﺷﻨﯽ، ﺳﻄﺢ ﻃﺒﯿﻌﯽ و ﺳﻄﺢ ﻃﺒﯿﻌﯽ ﺑﺎ ﻣﺎﻟﭻ ﺷﻨﯽ ﺑﻪﺗﺮﺗﯿﺐ ﺑﺮاﺑﺮ 67 ،84، ﺳﻪ و دو درﺻﺪ و آﺳﺘﺎﻧﻪ ﺑﺎرش ﺑﺮاي ﺷﺮوع رواﻧﺎب در ﺳﻄﻮح ﻣﺬﮐﻮر ﺑﻪﺗﺮﺗﯿﺐ ﺑﺮاﺑﺮ 2/56 ،0/28، 9/95 و 11/12 ﻣﯿﻠﯽ ﻣﺘﺮ اﺳﺖ. ﺑﻨﺎﺑﺮاﯾﻦ، ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﺑﺎرش ﻧﺮﻣﺎل ﺳﺎﻻﻧﻪ )245/7 ﻣﯿﻠﯽ ﻣﺘﺮ(، ﺣﺠﻢ رواﻧﺎب ﺟﻤﻊ ﺷﺪه ﺑﺮاي ﭘﻮﺷﺶ ژﺋﻮﻣﻤﺒﺮان، ﭘﻮﺷﺶ ﭘﻼﺳﺘﯿﮏ ﺑﺎ ﻣﺤﺎﻓﻆ ﺷﻨﯽ، ﺳﻄﺢ ﻃﺒﯿﻌﯽ و ﺳﻄﺢ ﻃﺒﯿﻌﯽ ﺑﺎ ﻣﺎﻟﭻ ﺷﻨﯽ ﺑﻪﺗﺮﺗﯿﺐ ﺑﺮاﺑﺮ 206، 164، ﻫﻔﺖ و ﭘﻨﺞ ﻟﯿﺘﺮ ﺑﺮ ﻣﺘﺮ ﻣﺮﺑﻊ در ﺳﺎل ﺧﻮاﻫﺪ ﺑﻮد. ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ ﻣﻘﺎﯾﺴﻪ ﻣﯿﺎﻧﮕﯿﻦ ﻫﺎ، ﺗﯿﻤﺎر ﭘﻮﺷﺶ ژﺋﻮﻣﻤﺒﺮان ﺑﻪ ﻋﻨﻮان ﯾﮏ ﮔﺰﯾﻨﻪ ﻣﻨﺎﺳﺐ در ﺗﻮﻟﯿﺪ رواﻧﺎب ﺗﺸﺨﯿﺺ داده ﺷﺪ. ﻫﻤﭽﻨﯿﻦ، وﺟﻮد ﻣﺎﻟﭻ ﺷﻨﯽ ﺑﺮ روي ﺳﻄﺢ ﻃﺒﯿﻌﯽ ﻣﻨﺠﺮ ﺑﻪ ﮐﺎﻫﺶ 10 ﺑﺮاﺑﺮي ﻓﺮﺳﺎﯾﺶ ﺧﺎك ﺷﺪه، ﻓﺮﺳﺎﯾﺶ ﺧﺎك را در ﻣﺪت دو ﺳﺎل، از 97 ﮔﺮم ﺑﺮ ﻣﺘﺮ ﻣﺮﺑﻊ ﺑﻪ 9/5 ﮔﺮم ﺑﺮ ﻣﺘﺮ ﻣﺮﺑﻊ ﮐﺎﻫﺶ ﻣﯽ دﻫﺪ.
چكيده لاتين :
Optimal use of rainfall in arid and semi-arid regions can play an important role in meeting the water needs of green space in low water seasons. On the other hand, poor vegetation can cause erosion and destruction in sloping lands that can be partially resolved if water and soil resources are properly managed. Rainfall is one of the most important sources of water supply for various uses. One of the methods of collecting rainwater is to make the ground impermeable and to maximize rainwater runoff. Impermeable surfaces can exist naturally like rock surfaces, or can be artificially created by covering the ground with materials such as asphalt, concrete, insulation sheets such as plastic, geomembrane and decamond. This study, which was carried out in the northern part of Tabriz, was conducted in four treatments, each with three replications of 4 m2 (2m×2m), including geomembrane cover area, plastic cover with sand protection, natural surface and natural surface with sand mulch. Results of 78 rainfall events over two years showed that in intermediate slopes of 33-38.6%, runoff from rainfall for geomembrane, plastic cover with sand protection, natural surface and natural surface with sand mulch were 84, 67, 3 and 2% of rainfall respectively and rainfall threshold for runoff at mentioned surfaces was 0.28, 2.56, 9.95 and 11.12 mm, respectively. Therefore, with respect to annual normal rainfall (245.7 mm), the volume of runoff accumulated for geomembrane, plastic cover with sand protection, natural surface and natural surface with sand mulch will be 206, 164, seven and five Lm-2 ina year, respectively. Comparing the means, the geomembrane cover treatment was identified as a suitable option for runoff production. Also, sand mulch on the natural surface reduces soil erosion from 97 to 9.5 grm-2 in two years.
