The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. H...The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. However, no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond. In this study, referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond, based on the general rules of water quality management in freshwater aquaculture system, a calculation mode was es- tablished to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system, which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the bal- ance between the ecological benefits and the economic benefits.展开更多
A dissolved oxygen fuzzy system predicting model based on neural network was put forward in this study. 106 groups of data were used to confirm the fitness of the predicting model. The first 80 groups of data were act...A dissolved oxygen fuzzy system predicting model based on neural network was put forward in this study. 106 groups of data were used to confirm the fitness of the predicting model. The first 80 groups of data were acted as training input and the other 26 groups of data were acted as the confirmed data in the system. The result showed that the testing data was approximately the same as the predicted data. So it gave a new way to solve the problem that the status of the water quality couldn＇t be predicted in time and it＇s hard to watching and measuring the factors dynamic.展开更多
The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established afte...The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established after sorting by importance of the factors by means of Delphi and expert investigation.In this study,index weight was confirmed according to the importance of the factors and relative membership grade of the measured values,thus and the fuzzy comprehensive evaluation model of aquaculture pond water quality was constructed,and the fuzzy comprehensive evaluation system of freshwater aquaculture pond water quality was designed and implemented.The application of this system in the assessment of aquaculture pond water quality by a company had achieved better result.展开更多
Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture ofL. vannamei is an important prelude to the continued development of shrimp culture ...Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture ofL. vannamei is an important prelude to the continued development of shrimp culture in China. In this study, we com- pared the respiratory metabolism of juvenile L. vannamei cultured in freshwater and saltwater by measuring their oxygen consump-tion rate （OCR）, ammonium-type nitrogen excretion rate （AER） and pyruvate kinase （PK） and lactate dehydrogenase （LDH） activi-ties at different molting stages in order to physiecologically characterize juvenile L. vannamei under freshwater conditions. The re- suits showed that OCR was significantly higher in saltwater than in freshwater at all stages of molting cycle. However, variation of OCR among molting stages in saltwater was similar with that in freshwater, and the highest OCR was observed at post-molting stage. At all stages of molting cycle, AER was significantly higher in freshwater than in saltwater, and the highest was observed at post-molting stage. The activity of PK was significantly higher in saltwater than in freshwater. Conversely, the activity of LDH was higher in freshwater than in saltwater in general. Significant variation of PK and LDH activities in molting cycle was observed in saltwater and freshwater. The results indicated that aerobic metabolism of juvenile L. vannamei was more active in saltwater than in freshwater; while its protein metabolism was more active in freshwater than in saltwater.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
The characteristics of an organic Rankin cycle designed to operate with a low temperature geothermal source and constant temperature cooling water supplied from freshwater ponds typical to those found near Waddan City...The characteristics of an organic Rankin cycle designed to operate with a low temperature geothermal source and constant temperature cooling water supplied from freshwater ponds typical to those found near Waddan City in the Al Jufrah region of Libya were examined. Two working fluids were examined and it was concluded that the most suitable for this application was R-245fa. The off design performance of the organic Rankine cycle was examined and it was shown that the cycle is controlled by the performance of the condenser which is cooling water side temperature limited.展开更多
Charophytes or stoneworts constitute a group of macrophytes that occur mostly in fresh-water environments but can also be found in brackish waters. Knowledge about stoneworts in Albania is still scarce and incomplete....Charophytes or stoneworts constitute a group of macrophytes that occur mostly in fresh-water environments but can also be found in brackish waters. Knowledge about stoneworts in Albania is still scarce and incomplete. According to published data on charoflora of Albania, there are 24 species and four genera known from different freshwater habitats. The present work is based on plant material sampled from 5 slightly brackish-water temporary ponds in the coastal area of Velipoja （north Albania）. During spring and summer of 2013-2015, field surveys were carried out with the main purpose of filling knowledge gaps concerning brackish water charophytes. Altogether seven species were identified： four typical of brackish water habitat （Chara baltica, Chara canescens, Chara galioides and Chara connivens） and three of broader tolerance （ Chara aspera, Chara vulgaris and Tolypella glomerata）. The first three species, which considered as the rarest and most threatened on the Balkans were found for the first time in Albania.展开更多
基金Supported by Special Fund for the Construction of Modern Agricultural Industry Technology System(CARS-46)Special Fund for Basic Research and Operating Expenses of Central-level Research Institutes(2007JBFA03)~~
文摘The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. However, no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond. In this study, referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond, based on the general rules of water quality management in freshwater aquaculture system, a calculation mode was es- tablished to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system, which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the bal- ance between the ecological benefits and the economic benefits.
基金Supported by National Natural Science Foundation of China (40801227)Open Foundation of Marine and Estuarine Fisheries Resources of Ministry of Agriculture and the Key Laboratory of Ecology (Open-2-04-09)~~
文摘A dissolved oxygen fuzzy system predicting model based on neural network was put forward in this study. 106 groups of data were used to confirm the fitness of the predicting model. The first 80 groups of data were acted as training input and the other 26 groups of data were acted as the confirmed data in the system. The result showed that the testing data was approximately the same as the predicted data. So it gave a new way to solve the problem that the status of the water quality couldn＇t be predicted in time and it＇s hard to watching and measuring the factors dynamic.
基金Supported by National Natural Science Foundation of China(40801227)Open Foundation of Key Open Laboratory of Marine and Estuarine Fishery Resources and Ecology, Ministry of Agriculture (Open-2-04-09)~~
文摘The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established after sorting by importance of the factors by means of Delphi and expert investigation.In this study,index weight was confirmed according to the importance of the factors and relative membership grade of the measured values,thus and the fuzzy comprehensive evaluation model of aquaculture pond water quality was constructed,and the fuzzy comprehensive evaluation system of freshwater aquaculture pond water quality was designed and implemented.The application of this system in the assessment of aquaculture pond water quality by a company had achieved better result.
基金supported by National Program on Key Basic Research Project (Grant No.2009CB118706)
文摘Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture ofL. vannamei is an important prelude to the continued development of shrimp culture in China. In this study, we com- pared the respiratory metabolism of juvenile L. vannamei cultured in freshwater and saltwater by measuring their oxygen consump-tion rate （OCR）, ammonium-type nitrogen excretion rate （AER） and pyruvate kinase （PK） and lactate dehydrogenase （LDH） activi-ties at different molting stages in order to physiecologically characterize juvenile L. vannamei under freshwater conditions. The re- suits showed that OCR was significantly higher in saltwater than in freshwater at all stages of molting cycle. However, variation of OCR among molting stages in saltwater was similar with that in freshwater, and the highest OCR was observed at post-molting stage. At all stages of molting cycle, AER was significantly higher in freshwater than in saltwater, and the highest was observed at post-molting stage. The activity of PK was significantly higher in saltwater than in freshwater. Conversely, the activity of LDH was higher in freshwater than in saltwater in general. Significant variation of PK and LDH activities in molting cycle was observed in saltwater and freshwater. The results indicated that aerobic metabolism of juvenile L. vannamei was more active in saltwater than in freshwater; while its protein metabolism was more active in freshwater than in saltwater.
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.
文摘The characteristics of an organic Rankin cycle designed to operate with a low temperature geothermal source and constant temperature cooling water supplied from freshwater ponds typical to those found near Waddan City in the Al Jufrah region of Libya were examined. Two working fluids were examined and it was concluded that the most suitable for this application was R-245fa. The off design performance of the organic Rankine cycle was examined and it was shown that the cycle is controlled by the performance of the condenser which is cooling water side temperature limited.
文摘Charophytes or stoneworts constitute a group of macrophytes that occur mostly in fresh-water environments but can also be found in brackish waters. Knowledge about stoneworts in Albania is still scarce and incomplete. According to published data on charoflora of Albania, there are 24 species and four genera known from different freshwater habitats. The present work is based on plant material sampled from 5 slightly brackish-water temporary ponds in the coastal area of Velipoja （north Albania）. During spring and summer of 2013-2015, field surveys were carried out with the main purpose of filling knowledge gaps concerning brackish water charophytes. Altogether seven species were identified： four typical of brackish water habitat （Chara baltica, Chara canescens, Chara galioides and Chara connivens） and three of broader tolerance （ Chara aspera, Chara vulgaris and Tolypella glomerata）. The first three species, which considered as the rarest and most threatened on the Balkans were found for the first time in Albania.
