The ecological processes and interrelationships between protists,either autotrophic or heterotrophic,and environmental factors in mariculture ponds are largely unknown.This study investigated the temporal dynamics of ...The ecological processes and interrelationships between protists,either autotrophic or heterotrophic,and environmental factors in mariculture ponds are largely unknown.This study investigated the temporal dynamics of potentially harmful dinoflagellate,Prorocentrum minimum (Pavillard) Schiller,and its relationship to physico-chemical factors and protozoan grazers over a complete cycle in a semi-enclosed shrimp-farming pond near Qingdao,Northern China.P.minimum occurred frequently in low numbers from June to August,followed by a sharp increase from the middle of August,reaching a single maximum peak value of 2.2×105 cells L-1 in October.Temporal variation in abundance was positively correlated with dissolved nitrogen,but showed a significant inverse relationship to abundance of the dominant ciliates,Tintinnopsis lohmanni and Askenasia stellaris.The results provide statistical evidence that the number of P.minimum increased with increasing nitrogen,and the suppression or shortening of algal bloom may be associated with protozoan grazers,such as Tintinnopsis lohmanni,in mariculture ponds.展开更多
Ridgetail white prawn (Exopalaemon carinicauda) are of significant economic importance in China where they are widely cultured. However, there is little information on the basic biology of this species. We evaluated...Ridgetail white prawn (Exopalaemon carinicauda) are of significant economic importance in China where they are widely cultured. However, there is little information on the basic biology of this species. We evaluated the effect of temperature (16, 19, 22, 25, 28, 31, and 34℃) on the standard metabolic rates (SMRs) of juvenile and adult E. carinicauda in the laboratory under static conditions. The oxygen consumption rate (OCR), ammonia-N excretion rate (AER), and atornic ratio of oxygen consumed to nitrogen consumed (O:N ratio) of juvenile and adult E. carinicauda were significantly influenced by temperature (P〈0.05). Both the OCR and AER of juveniles increased significantly with increasing temperature from 16 to 34℃, but the maximum OCR for adults was at 31℃. Juvenile shrimp exhibited a higher OCR than the adults from 19 to 34℃. There was no significant difference between the AERs of the two life-stages from 16 to 31 ℃ (P〉0.05). The O:N ratio in juveniles was significantly higher than that in the adults over the entire temperature range (P〈0.05). The temperature coefficient (Q_10) of OCR and AER ranged from 5.03 to 0.86 and 6,30 to 0.85 for the adults, respectively, and from 6,09-1.03 and 3.66-1.80 for the juveniles, respectively. The optimal temperature range for growth of the juvenile and adult shrimp was from 28 to 31℃, based on Q_10 and SMR values. Results from the present study may be used to guide pond culture production ofE. carinicauda.展开更多
Chlorella vulgaris is a single-cell, spherical green algae and one of the microalgae on which many applied studies are conducted. In the present study, five strains displaying fast and efficient reproduction were chos...Chlorella vulgaris is a single-cell, spherical green algae and one of the microalgae on which many applied studies are conducted. In the present study, five strains displaying fast and efficient reproduction were chosen among 11 C. vulgaris strains isolated from different fresh water ponds and their cell numbers and the amount of chlorophyll a, protein, lipid, cellulose and carbohydrate were examined. The main goal of the study is to investigate increasing the biochemical contents especially the protein content of C. vulgaris strains in different mediums. In the present study, cell densities were determined through cell count for five days. In parallel with cell count, their chlorophyll a content was determined. The highest cell density was observed with C. vulgaris TOH (Tourism and Hotel Management Pond) strain as 5.5 × 104 h/mL, and the chlorophyll a content as 4.3 × 102 mg/m3. The highest intracellular protein amount was determined with C. vulgaris GUH (Gazi University Rectorship Pond) (0.061 g/100 mL) and the highest lipid amount was attained with C. vulgaris UIK (Ulus Construction Well) strain as 0.019 g/100 mL. The process of increasing the intracellular protein amount in C. vulgaris GUH strain was carried out in Prat, Yagojinski and Chlorella medium. The results indicated that Chlorella medium increased the intracellular protein amount.展开更多
基金Supported by the National Natural Science Foundation of China (No. 40976075)a Post-Doctoral Fellowship of Inha University,a Grant from the Center of Excellence in Biodiversity Research,King Saud University and 111 project of China (No. B08049)
文摘The ecological processes and interrelationships between protists,either autotrophic or heterotrophic,and environmental factors in mariculture ponds are largely unknown.This study investigated the temporal dynamics of potentially harmful dinoflagellate,Prorocentrum minimum (Pavillard) Schiller,and its relationship to physico-chemical factors and protozoan grazers over a complete cycle in a semi-enclosed shrimp-farming pond near Qingdao,Northern China.P.minimum occurred frequently in low numbers from June to August,followed by a sharp increase from the middle of August,reaching a single maximum peak value of 2.2×105 cells L-1 in October.Temporal variation in abundance was positively correlated with dissolved nitrogen,but showed a significant inverse relationship to abundance of the dominant ciliates,Tintinnopsis lohmanni and Askenasia stellaris.The results provide statistical evidence that the number of P.minimum increased with increasing nitrogen,and the suppression or shortening of algal bloom may be associated with protozoan grazers,such as Tintinnopsis lohmanni,in mariculture ponds.
基金Supported by the National Key Technology Research and Development Program of China(No.2011BAD13B01)the National Natural Science Foundation of China(General Program)(No.41376165)the China Agriculture Research System CARS-47
文摘Ridgetail white prawn (Exopalaemon carinicauda) are of significant economic importance in China where they are widely cultured. However, there is little information on the basic biology of this species. We evaluated the effect of temperature (16, 19, 22, 25, 28, 31, and 34℃) on the standard metabolic rates (SMRs) of juvenile and adult E. carinicauda in the laboratory under static conditions. The oxygen consumption rate (OCR), ammonia-N excretion rate (AER), and atornic ratio of oxygen consumed to nitrogen consumed (O:N ratio) of juvenile and adult E. carinicauda were significantly influenced by temperature (P〈0.05). Both the OCR and AER of juveniles increased significantly with increasing temperature from 16 to 34℃, but the maximum OCR for adults was at 31℃. Juvenile shrimp exhibited a higher OCR than the adults from 19 to 34℃. There was no significant difference between the AERs of the two life-stages from 16 to 31 ℃ (P〉0.05). The O:N ratio in juveniles was significantly higher than that in the adults over the entire temperature range (P〈0.05). The temperature coefficient (Q_10) of OCR and AER ranged from 5.03 to 0.86 and 6,30 to 0.85 for the adults, respectively, and from 6,09-1.03 and 3.66-1.80 for the juveniles, respectively. The optimal temperature range for growth of the juvenile and adult shrimp was from 28 to 31℃, based on Q_10 and SMR values. Results from the present study may be used to guide pond culture production ofE. carinicauda.
文摘Chlorella vulgaris is a single-cell, spherical green algae and one of the microalgae on which many applied studies are conducted. In the present study, five strains displaying fast and efficient reproduction were chosen among 11 C. vulgaris strains isolated from different fresh water ponds and their cell numbers and the amount of chlorophyll a, protein, lipid, cellulose and carbohydrate were examined. The main goal of the study is to investigate increasing the biochemical contents especially the protein content of C. vulgaris strains in different mediums. In the present study, cell densities were determined through cell count for five days. In parallel with cell count, their chlorophyll a content was determined. The highest cell density was observed with C. vulgaris TOH (Tourism and Hotel Management Pond) strain as 5.5 × 104 h/mL, and the chlorophyll a content as 4.3 × 102 mg/m3. The highest intracellular protein amount was determined with C. vulgaris GUH (Gazi University Rectorship Pond) (0.061 g/100 mL) and the highest lipid amount was attained with C. vulgaris UIK (Ulus Construction Well) strain as 0.019 g/100 mL. The process of increasing the intracellular protein amount in C. vulgaris GUH strain was carried out in Prat, Yagojinski and Chlorella medium. The results indicated that Chlorella medium increased the intracellular protein amount.