Although chub mackerel （Scomberjaponicus） is a primary pelagic fish species, we have only limited knowledge on its key life history processes. The present work studied the age and growth of chub mackerel in the East...Although chub mackerel （Scomberjaponicus） is a primary pelagic fish species, we have only limited knowledge on its key life history processes. The present work studied the age and growth of chub mackerel in the East China and Yellow Seas. Age was determined by interpreting and counting growth rings on the sagitta otoliths of 252 adult fish caught by the Chinese commercial purse seine fleet during the period from November 2006 to January 2007 and 150 juveniles from bottom trawl surveys on the spawning ground in May 2006. The difference between the assumed birth date of 1st April and date of capture was used to adjust the age determined from counting the number of complete translucent rings. The parameters of three commonly used growth models, the von Bertalanffy, Logistic and Gompertz models, were estimated using the maximum likelihood method. Based on the Akaike Information Criterion （AIC）, the yon Bertalanffy growth model was found to be the most appropriate model. The size-at-age and size-at-maturity values were also found to decrease greatly compared with the results achieved in the 1950s, which was caused by heavy exploitation over the last few decades.展开更多
Biochemical composition and nutritional value of muscle tissue of wild-caught yellowback seabream （Evynnis tumifrons） from the East China Sea were determined. The yellowback seabream muscle contained 18.30% crude pr...Biochemical composition and nutritional value of muscle tissue of wild-caught yellowback seabream （Evynnis tumifrons） from the East China Sea were determined. The yellowback seabream muscle contained 18.30% crude protein and 0.47% crude lipid. The contents of biochemical, moisture, crude protein, crude lipid, and ash were analyzed using AOAC standard methods. The compositions and contents of amino-acid and fatty-acid were determined by Amino Acid 20 Analyzer and Agilent 6890 Gas Chromatograph. The total essential amino acids （EAA; those required by humans） accounts for 46.96% of the total amino acids in E. tumifrons, higher than FAO/WHO standard but lower than whole-egg protein standard. In E. tumifrons, the first limiting amino acids were threonine （Thr）, based on amino acid score （AAS）, and methionine （Met） and cysteine （Cys）, based on chemical score （CS）. A total of 19 fatty acids were identified; together, eicosapentaenoic acid （EPA） and docosahexaenoic acid （DHA） contributed 22.65% of the total fatty-acid content, with 17.25% from DHA. The nutritional-requirement characteristics of this fish, which tumifrons mariculture. composition data provided useful information on the food quality and may facilitate the development of appropriate feed formulation in E.展开更多
The biomass and energy production of Casuarina equisetifolia plantations aged 14 were studied in Huian County, Fujian Province, Southeast of China. The standing crop biomass was 152.60 t/ha, in which the biomass of bo...The biomass and energy production of Casuarina equisetifolia plantations aged 14 were studied in Huian County, Fujian Province, Southeast of China. The standing crop biomass was 152.60 t/ha, in which the biomass of bole was 67.02 t/ha, accounting for 43.94 % of the total, while that of root was 36.83 t/ha and 24.14 %, respectively. Net primary productivity was 10.17t/(ha.a).The range of gross caloric of components was 19.29～20.23 kJ/g, with the average 19.70 kJ/g. The standing crop energy was 2 987×10^6 kJ/ha. Net energy production was 196.8×10^6 kJ/ha, while solar energy conversion efficiency was 0.90%.展开更多
基金the Program for New Century Excellent Talents in University (NCET-06-0437)Shanghai Leading Academic Discipline Project (No T1101)
文摘Although chub mackerel （Scomberjaponicus） is a primary pelagic fish species, we have only limited knowledge on its key life history processes. The present work studied the age and growth of chub mackerel in the East China and Yellow Seas. Age was determined by interpreting and counting growth rings on the sagitta otoliths of 252 adult fish caught by the Chinese commercial purse seine fleet during the period from November 2006 to January 2007 and 150 juveniles from bottom trawl surveys on the spawning ground in May 2006. The difference between the assumed birth date of 1st April and date of capture was used to adjust the age determined from counting the number of complete translucent rings. The parameters of three commonly used growth models, the von Bertalanffy, Logistic and Gompertz models, were estimated using the maximum likelihood method. Based on the Akaike Information Criterion （AIC）, the yon Bertalanffy growth model was found to be the most appropriate model. The size-at-age and size-at-maturity values were also found to decrease greatly compared with the results achieved in the 1950s, which was caused by heavy exploitation over the last few decades.
文摘Biochemical composition and nutritional value of muscle tissue of wild-caught yellowback seabream （Evynnis tumifrons） from the East China Sea were determined. The yellowback seabream muscle contained 18.30% crude protein and 0.47% crude lipid. The contents of biochemical, moisture, crude protein, crude lipid, and ash were analyzed using AOAC standard methods. The compositions and contents of amino-acid and fatty-acid were determined by Amino Acid 20 Analyzer and Agilent 6890 Gas Chromatograph. The total essential amino acids （EAA; those required by humans） accounts for 46.96% of the total amino acids in E. tumifrons, higher than FAO/WHO standard but lower than whole-egg protein standard. In E. tumifrons, the first limiting amino acids were threonine （Thr）, based on amino acid score （AAS）, and methionine （Met） and cysteine （Cys）, based on chemical score （CS）. A total of 19 fatty acids were identified; together, eicosapentaenoic acid （EPA） and docosahexaenoic acid （DHA） contributed 22.65% of the total fatty-acid content, with 17.25% from DHA. The nutritional-requirement characteristics of this fish, which tumifrons mariculture. composition data provided useful information on the food quality and may facilitate the development of appropriate feed formulation in E.
文摘The biomass and energy production of Casuarina equisetifolia plantations aged 14 were studied in Huian County, Fujian Province, Southeast of China. The standing crop biomass was 152.60 t/ha, in which the biomass of bole was 67.02 t/ha, accounting for 43.94 % of the total, while that of root was 36.83 t/ha and 24.14 %, respectively. Net primary productivity was 10.17t/(ha.a).The range of gross caloric of components was 19.29～20.23 kJ/g, with the average 19.70 kJ/g. The standing crop energy was 2 987×10^6 kJ/ha. Net energy production was 196.8×10^6 kJ/ha, while solar energy conversion efficiency was 0.90%.
