Objective: To analyze the growth prediction results of crayfish (Astacus leptodactylus Eschscholtz 1823) with two methods of length-weight relation (LWR) and artificial neural networks (ANNs). Methods: We examine the ...Objective: To analyze the growth prediction results of crayfish (Astacus leptodactylus Eschscholtz 1823) with two methods of length-weight relation (LWR) and artificial neural networks (ANNs). Methods: We examine the relationships between total length and total weight;carapace length and total weight;carapace length and total length for Astacus leptodactylus caught from E?irdir Lake between 2013 and 2014. Length weight relation is used as a traditional method and artificial neural networks as a new approach. Results: The research is based on a sample of 222 crayfish (34% (75 individual) female, 66%(147 individual) male)The outcomes of the research can be summarized as follows: average total length is 128.40 mm for female and 135.50 mm for male;average total weight is 59.79 g for female and 82.95 g for male crayfish. LWR equation was found to be W = 0.05425196 L2.73 for females, W = 0.05272102 L2.81 for males, and W = 0.03589889 L2.94 for the entire sample, regardless of gender. The results acquired from ANNs and LWR are analyzed to those obtained by the growth rate of crayfish caught from E?irdir Lake. Conclutions: LWR and ANNs mean absolute percentage error results were examined. ANNs provide better results than the LWR. ANNs can be considered as an alternative for growth estimation.展开更多
Objective:To determine Fe,Cu,Zn,Pb and Cd concentrations in muscle of sind sardinella[Sardinella sindensis(S.sindensis)]from Balochistan coast,Pakistan.Methods:S.sindensis were collected from Balochistan coast,Pakista...Objective:To determine Fe,Cu,Zn,Pb and Cd concentrations in muscle of sind sardinella[Sardinella sindensis(S.sindensis)]from Balochistan coast,Pakistan.Methods:S.sindensis were collected from Balochistan coast,Pakistan,at autumn inter monsoon,north east monsoon,spring inter monsoon and south west monsoon during October 2005-September 2006.All samples were analyzed for Fe,Cu,Zn,Pb and Cd by AAnalyst 700 flame atomic absorption spectrophotometer.Results:Generally,S.sindensis caught from Balochistan coast showed the accumulation level of Fe[(16.88±5.60)μg/g],Cu[(2.74±1.89)μg/g],Cd[(0.29±0.25)μg/g],Zn[(4.29±2.31)μg/g]and Pb[(0.24±0.24)μg/g]in the muscle tissues.Conclusions:The metal concentrations in fish from Balochistan coast observed in this study were lower than the limit values.Therefore,all metal accumulations in S.sindensis have to be monitored continuously,especially in this region.展开更多
文摘Objective: To analyze the growth prediction results of crayfish (Astacus leptodactylus Eschscholtz 1823) with two methods of length-weight relation (LWR) and artificial neural networks (ANNs). Methods: We examine the relationships between total length and total weight;carapace length and total weight;carapace length and total length for Astacus leptodactylus caught from E?irdir Lake between 2013 and 2014. Length weight relation is used as a traditional method and artificial neural networks as a new approach. Results: The research is based on a sample of 222 crayfish (34% (75 individual) female, 66%(147 individual) male)The outcomes of the research can be summarized as follows: average total length is 128.40 mm for female and 135.50 mm for male;average total weight is 59.79 g for female and 82.95 g for male crayfish. LWR equation was found to be W = 0.05425196 L2.73 for females, W = 0.05272102 L2.81 for males, and W = 0.03589889 L2.94 for the entire sample, regardless of gender. The results acquired from ANNs and LWR are analyzed to those obtained by the growth rate of crayfish caught from E?irdir Lake. Conclutions: LWR and ANNs mean absolute percentage error results were examined. ANNs provide better results than the LWR. ANNs can be considered as an alternative for growth estimation.
文摘Objective:To determine Fe,Cu,Zn,Pb and Cd concentrations in muscle of sind sardinella[Sardinella sindensis(S.sindensis)]from Balochistan coast,Pakistan.Methods:S.sindensis were collected from Balochistan coast,Pakistan,at autumn inter monsoon,north east monsoon,spring inter monsoon and south west monsoon during October 2005-September 2006.All samples were analyzed for Fe,Cu,Zn,Pb and Cd by AAnalyst 700 flame atomic absorption spectrophotometer.Results:Generally,S.sindensis caught from Balochistan coast showed the accumulation level of Fe[(16.88±5.60)μg/g],Cu[(2.74±1.89)μg/g],Cd[(0.29±0.25)μg/g],Zn[(4.29±2.31)μg/g]and Pb[(0.24±0.24)μg/g]in the muscle tissues.Conclusions:The metal concentrations in fish from Balochistan coast observed in this study were lower than the limit values.Therefore,all metal accumulations in S.sindensis have to be monitored continuously,especially in this region.