[Objective]The study was to monitor the indoor environmental parameters of broiler house with three-overlap cages and analyze the differences in winter and autumn. [Method] In the process of feeding,the same broiler h...[Objective]The study was to monitor the indoor environmental parameters of broiler house with three-overlap cages and analyze the differences in winter and autumn. [Method] In the process of feeding,the same broiler house in the same farm was chosen to determine indoor ambient temperature,humidity and air quality at 3-6 weeks age of broilers in different seasons. The measure points were distributed in four different positions in the house. [Result] There was no significant difference in ambient temperature between autumn and winter( P > 0. 05). The ambient temperature in the house in winter was slightly higher than that in autumn. The humidity in autumn was significantly higher than that in winter( P < 0. 05). The temperature and humidity in two seasons could meet the requirements of broiler growth. There was no significant difference( P > 0. 05) in ammonia concentration between autumn and winter,while ammonia concentration in winter was slightly higher than that in autumn. The carbon dioxide concentration of broiler house in winter was significantly higher than that in autumn( P < 0. 05).The total number of airborne bacteria in winter was significantly higher than that in autumn( P < 0. 05). [Conclusion]The indoor temperature kept constant in autumn and winter seasons in closed poultry house. In winter,the humidity was reduced,the carbon dioxide concentration was increased,and the total number of bacteria in the air was increased. The ventilation in winter should be increased in case of heat preservation.展开更多
Impact of LaMmichthys crocea cage culture in Daiqu fishery （Zhoushan, Zhejiang Province） on the chemistry of the sediment was inves- tigated. Sediment samples, in different depths and from three stations at various ...Impact of LaMmichthys crocea cage culture in Daiqu fishery （Zhoushan, Zhejiang Province） on the chemistry of the sediment was inves- tigated. Sediment samples, in different depths and from three stations at various distances from the cage, were collected, for analyzing total organic matter, total organic carbon, total nitrogen and phosphorus. The results showed a significant increase in all analyzed parameters in station 1, at 5 m from the cage. The difference between reference station （600 m from the cage） and station 2 at 95 m to the cage was insignificant, indicating lo- calized impact of cage farming to the vicinity of cage. The analyzed parameters in various depths did not show a significant difference. The values of analyzed parameters in the perimeter of the cage and their differences with reference stations showed small magnitude and localized impact on the chemistry of sediment. It might be because of deep water and moderate velocity of water current in this fjord. The magnitude of impact may dif- fer durina the summer when biomass and feedina rate would be at the maximum level.展开更多
The present study investigated the applicability of integrated polychaete-fish culture for fish waste removal to offset negative impact induced by organic benthic enrichment.A field study demonstrated that deposition ...The present study investigated the applicability of integrated polychaete-fish culture for fish waste removal to offset negative impact induced by organic benthic enrichment.A field study demonstrated that deposition rate was significantly higher underneath the fish farm than that in control area.The material settling under the farm was characterized by a high amount of fish feces(45%) and uneaten feed(27%).Both feeding rate(FR) and apparent digestibility rate(ADR) increased with decreasing body weight,as was indicated by significantly a higher rate observed for the groups containing smaller individuals in a lab study.The nutrient in fresh deposited material(De) was higher than that in sediments collected under the farm(Se),resulting in lower feces production but higher apparent digestibility rate for the De group as feeding rate was similar.Consequently,higher nutrient removal efficiency was observed in the De group.A mass balance approach indicated that approximately 400–500 individuals m^(-2) is required for removing all waste materials deposited underneath the fish farm,whereas abundance can be lower(about 300–350 individuals m^(-2)) when only the fish waste needs to be removed.The results showed that a significant amount of waste had been accumulated in the fish cages in Sanggou Bay.The integration of fish with P.aibuhitensis seems promising for preventing organic pollution in the sediment and therefore is an effective strategy for mitigating negative effect of fish farms.Thus such integration can become a new IMTA(integrated multi-trophic aquaculture) model in Sanggou Bay.展开更多
In the present study, the dynamic response of a coupled SPM-feeder-cage system under irregular waves and shear currents is analyzed. A numerical model is developed by using the commercial software Orca Flex. Hydrodyna...In the present study, the dynamic response of a coupled SPM-feeder-cage system under irregular waves and shear currents is analyzed. A numerical model is developed by using the commercial software Orca Flex. Hydrodynamics coefficients of the vessel are calculated by using a 3D diffraction/radiation panel program. First- and second-order wave forces are included in the calculations. Morison equation is used to compute the drag force on line elements representing the net. Drag coefficients are determined at every time step in the simulation considering the relative normal velocity between the structural elements and the fluid flow. The dynamic response of the coupled system is analyzed for various environments and net materials. The results of the study show the effects of solidity ratio of the net and vertical positions of the cage on the overall dynamic response of the system, confirming the viability of this type of configuration for future development of offshore aquaculture in deep waters.展开更多
基金Supported by Science and Technology Project of Shanxi Province(20140311021-2)Key Research Project of Shanxi Academy of Agricultural Sciences(YGG1609)Special Fund of China Agricultural Industry Research System(CARS-42)
文摘[Objective]The study was to monitor the indoor environmental parameters of broiler house with three-overlap cages and analyze the differences in winter and autumn. [Method] In the process of feeding,the same broiler house in the same farm was chosen to determine indoor ambient temperature,humidity and air quality at 3-6 weeks age of broilers in different seasons. The measure points were distributed in four different positions in the house. [Result] There was no significant difference in ambient temperature between autumn and winter( P > 0. 05). The ambient temperature in the house in winter was slightly higher than that in autumn. The humidity in autumn was significantly higher than that in winter( P < 0. 05). The temperature and humidity in two seasons could meet the requirements of broiler growth. There was no significant difference( P > 0. 05) in ammonia concentration between autumn and winter,while ammonia concentration in winter was slightly higher than that in autumn. The carbon dioxide concentration of broiler house in winter was significantly higher than that in autumn( P < 0. 05).The total number of airborne bacteria in winter was significantly higher than that in autumn( P < 0. 05). [Conclusion]The indoor temperature kept constant in autumn and winter seasons in closed poultry house. In winter,the humidity was reduced,the carbon dioxide concentration was increased,and the total number of bacteria in the air was increased. The ventilation in winter should be increased in case of heat preservation.
基金Supported by Zhejiang Provincial Natural Science Foundation of China(LQ13D060001,LY14D060003)
文摘Impact of LaMmichthys crocea cage culture in Daiqu fishery （Zhoushan, Zhejiang Province） on the chemistry of the sediment was inves- tigated. Sediment samples, in different depths and from three stations at various distances from the cage, were collected, for analyzing total organic matter, total organic carbon, total nitrogen and phosphorus. The results showed a significant increase in all analyzed parameters in station 1, at 5 m from the cage. The difference between reference station （600 m from the cage） and station 2 at 95 m to the cage was insignificant, indicating lo- calized impact of cage farming to the vicinity of cage. The analyzed parameters in various depths did not show a significant difference. The values of analyzed parameters in the perimeter of the cage and their differences with reference stations showed small magnitude and localized impact on the chemistry of sediment. It might be because of deep water and moderate velocity of water current in this fjord. The magnitude of impact may dif- fer durina the summer when biomass and feedina rate would be at the maximum level.
基金supported by Primary Research&Development Plan of Shandong Province(2016GGF01068)the National Natural Science Foundation of China(Nos.31302193,41676147)+3 种基金Environment and Aquaculture Governance(CHN-2152,13/0033)Public Funds of Key Laboratory of East China Sea&Oceanic Fishery Resources Exploitation and Utilization,Ministry of Agriculture,P.R.China(2013K06)the Special Scientific Research Funds for Central Non-profit Institutes,Yellow Sea Fisheries Research Institutes(20603022015017)National Natural Science Foundation of China 41306117)
文摘The present study investigated the applicability of integrated polychaete-fish culture for fish waste removal to offset negative impact induced by organic benthic enrichment.A field study demonstrated that deposition rate was significantly higher underneath the fish farm than that in control area.The material settling under the farm was characterized by a high amount of fish feces(45%) and uneaten feed(27%).Both feeding rate(FR) and apparent digestibility rate(ADR) increased with decreasing body weight,as was indicated by significantly a higher rate observed for the groups containing smaller individuals in a lab study.The nutrient in fresh deposited material(De) was higher than that in sediments collected under the farm(Se),resulting in lower feces production but higher apparent digestibility rate for the De group as feeding rate was similar.Consequently,higher nutrient removal efficiency was observed in the De group.A mass balance approach indicated that approximately 400–500 individuals m^(-2) is required for removing all waste materials deposited underneath the fish farm,whereas abundance can be lower(about 300–350 individuals m^(-2)) when only the fish waste needs to be removed.The results showed that a significant amount of waste had been accumulated in the fish cages in Sanggou Bay.The integration of fish with P.aibuhitensis seems promising for preventing organic pollution in the sediment and therefore is an effective strategy for mitigating negative effect of fish farms.Thus such integration can become a new IMTA(integrated multi-trophic aquaculture) model in Sanggou Bay.
基金Kampachi Farms LLC for their support to complete this work and for all the technical information provided to complete the numerical model
文摘In the present study, the dynamic response of a coupled SPM-feeder-cage system under irregular waves and shear currents is analyzed. A numerical model is developed by using the commercial software Orca Flex. Hydrodynamics coefficients of the vessel are calculated by using a 3D diffraction/radiation panel program. First- and second-order wave forces are included in the calculations. Morison equation is used to compute the drag force on line elements representing the net. Drag coefficients are determined at every time step in the simulation considering the relative normal velocity between the structural elements and the fluid flow. The dynamic response of the coupled system is analyzed for various environments and net materials. The results of the study show the effects of solidity ratio of the net and vertical positions of the cage on the overall dynamic response of the system, confirming the viability of this type of configuration for future development of offshore aquaculture in deep waters.
