اثر تراكم‌هاي مختلف فيل‌ماهي (Huso huso) بر شاخص‌هاي رشد و كل مواد آلي بستر در سيستم يكپارچه، با استفاده از فعاليت زيست پالايي كرم نرئيس (Nereis diversicolor)

Effects of different densities of beluga sturgeon (Huso huso) on growth indices and total organic matter in integrated system using the bioremediation activity of Nereis worm (Nereis diversicolor

ﺗﺮاﮐﻢﻫﺎي ﻣﺨﺘﻠﻒ ﻓﯿﻞﻣﺎﻫﯽ ﺑﺮ ﺗﻮﻟﯿﺪ ﻓﯿﻞﻣﺎﻫﯽ و ﮐﺮم ﻧﺮﺋﯿﺲ و ﺗﺼﻔﯿﻪ ﮐﻞ ﻣﻮاد آﻟﯽ ﺑﺴﺘﺮ در ﺳﯿﺴﺘﻢ ﯾﮑﭙﺎرﭼﻪ ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﻗﺮار ﮔﺮﻓﺖ. ﻓﯿﻞﻣﺎﻫﯿﺎن ﺑﺎ وزن اوﻟﯿﻪ 0/32 ± 140/44 ﮔﺮم در ﻃﯽ 60 روز ﺑﺎ ﺳﻪ ﺗﺮاﮐﻢ 4 ،2 و 8 ﻋﺪد در ﻫﺮ ﻣﺨﺰن ﭘﺮورش داده ﺷﺪﻧﺪ. آب ﺧﺮوﺟﯽ ﻣﺨﺰن ﭘﺮورش ﻣﺎﻫﯽ اﺑﺘﺪا وارد ﻣﺨﺰن ﭘﺮورﺷﯽ ﮐﺮم ﻧﺮﺋﯿﺲ و ﺳﭙﺲ ﻣﺨﺰن ﺑﯿﻮﻓﯿﻠﺘﺮ ﻣﯽﺷﺪ و ﭘﺲ از ﺗﺼﻔﯿﻪ در اﯾﻦ ﻣﺨﺎزن دوﺑﺎره ﺑﻪ ﺳﯿﺴﺘﻢ ﺑﺮﮔﺸﺖ داده ﻣﯽﺷﺪ. در اﯾﻦ ﺳﯿﺴﺘﻢ از ﮐﺮم ﻧﺮﺋﯿﺲ ﺑﻪﻋﻨﻮان ﯾﮏ زﯾﺴﺖ ﭘﺎﻻﯾﻨﺪه و ﯾﮏ ﻣﺤﺼﻮل ﺟﺎﻧﺒﯽ اﺳﺘﻔﺎده ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﻓﺎﮐﺘﻮرﻫﺎي رﺷﺪ ﻣﺎﻫﯽ ﺑﺎ اﻓﺰاﯾﺶ ﺗﺮاﮐﻢ ﻧﺴﺒﺖ ﻣﻌﮑﻮس دارد ﺑﻪﻃﻮريﮐﻪ ﺣﺪاﮐﺜﺮ درﺻﺪ اﻓﺰاﯾﺶ وزن ﺑﺪن و اﻓﺰاﯾﺶ وزن ﻓﯿﻞﻣﺎﻫﯽ ﺑﻪ ﺗﺮﺗﯿﺐ ﺑﻪ ﻣﯿﺰان 1/5± 93/86 درﺻﺪ و 1/7± 124/61 ﮔﺮم در ﺗﺮاﮐﻢ ﮐﻢ ﻣﺸﺎﻫﺪه ﺷﺪ. ﺑﺎ اﯾﻦ وﺟﻮد اﻓﺰاﯾﺶ ﺗﺮاﮐﻢ ﺑﺎﻋﺚ اﻓﺰاﯾﺶ ﺗﻮﻟﯿﺪ در واﺣﺪ ﺳﻄﺢ ﻣﺎﻫﯽ ﺷﺪ. ﺑﻪﻃﻮريﮐﻪ ﺑﯿﻮﻣﺲ ﻧﻬﺎﯾﯽ ﺑﭽﻪ ﻣﺎﻫﯿﺎن ﺑﺎ ﻣﯿﺰان 5/28±0/09 ﮐﯿﻠﻮﮔﺮم ﺑﺮ ﻣﺘﺮﻣﺮﺑﻊ در ﺗﺮاﮐﻢ ﺑﺎﻻ ﻣﺸﺎﻫﺪه ﺷﺪ. اﺧﺘﻼف ﻣﻌﻨﯽدار در ﻣﯿﺰان ﮐﻞ ﻣﻮاد آﻟﯽ ﺑﺴﺘﺮ در ﺳﻪ ﺗﺮاﮐﻢ ﻣﺨﺘﻠﻒ ﻣﺸﺎﻫﺪه ﻧﺸﺪ )0/05>P(. ﻫﻤﺒﺴﺘﮕﯽ ﺑﺎﻻﯾﯽ ﺑﯿﻦ ﺗﺮاﮐﻢﻫﺎي ﻣﺨﺘﻠﻒ ﻣﺎﻫﯽ و ﺣﺬف ﻣﻮاد آﻟﯽ ﺑﺴﺘﺮ ﻣﺸﺎﻫﺪه ﺷﺪ. ﮐﻤﺘﺮﯾﻦ ﮐﻞ ﻣﻮاد آﻟﯽ ﺑﺴﺘﺮ ﺑﺎ ﻣﯿﺰان 0/94± 2/66 ﮔﺮم ﺑﻪ ﺗﺮاﮐﻢ ﺑﺎﻻ ﻣﺮﺑﻮط ﺑﻮد. ﻧﺘﺎﯾﺞ اﯾﻦ آزﻣﺎﯾﺶ ﻧﺸﺎن داد ﮐﻪ ﻗﺎﺑﻞ اﻃﻤﯿﻨﺎنﺗﺮﯾﻦ ﺗﺮاﮐﻢ از ﻧﻈﺮ ﺗﻮﻟﯿﺪ ﻣﺎﻫﯽ و ﮐﺎرآﯾﯽ ﺗﺼﻔﯿﻪ ﺳﯿﺴﺘﻢ ﺗﺮاﮐﻢ 8 ﻋﺪد ﻣﺎﻫﯽ در80 ﻟﯿﺘﺮ اﺳﺖ.

Laboratory examinations on the effect of different densities on production of beluga and Nereis diversicolor worm and purification of total organic matter was carried out in an integrated system. Juvenile beluga with initial weight of 140.44±0.32 g were reared during 60 days with three densities of 2, 4 and 8 fish per tanks. Outlet water of the fish tanks was entered to the Nereis worm tank then was entered to the biofilter tank then after cleaning on this tanks water was returned again into the system. In this system, the Nereis worm was used both as a bioremediator and also byproduct. The results showed that growth factors of fish and increasing of density have related inversely. So that the maximum percentage of body weight increase and weight gain of beluga were 93.86±1.5% and 124.61±1.7 g respectively in low density. However, increased density caused increases in production of fish per unit area. So that highest final biomass of juvenile’s 5.28±0.09 kg/m2 were observed in high density. The lowest amount of total organic matter on the substrate with 2.66±0.94 g/mg was related to high density. The results of this experiment showed that the reliable stocking density is 8 per tank for fish production and bioremediation efficiency of system.