大口黑鲈池塘内循环流水养殖模式温室气体减排及影响因子OA

In this study,largemouth bass(Micropterus salmoides)was selected for research,and we investigated the greenhouse gas(GHG)flux(CO2,CH4,and N2O)at the water-air interface under two aquaculture operating systems:inner-pond raceway aquaculture(IPRA)and conventional pond aquacul-ture(UPA).By simultaneously measuring water quality parameters and meteorological factors,we ana-lyzed correlations among variables and identified key drivers of the GHG flux.The aim of the study was to explore the potential reduction in greenhouse gas emissions when using IPRA rather than UPA,and to extend the database on greenhouse gas emissions from freshwater aquaculture.From April 4 to Novem-ber 31 of 2023,we carried out a M.salmoides aquaculture experiment comparing IPRA and UPA,and greenhouse gas fluxes from each system were determined using the closed static opaque chamber-GC method.Water quality indicators and meteorological parameters were measured simultaneously for correlation analysis.In the IPRA culture zone and water purification zones,and in the UPA system,the respective CO2 emission fluxes were in the ranges of-10.14-761.13 mg/(m2·h),-89.92-302.31 mg/(m2·h),and-32.57-492.74 mg/(m2·h),the respective CH4 emission fluxes were in the ranges of-0.26-2.65 mg/(m2h),-0.25-1.52 mg/(m2·h),and 0.10-2.31 mg/(m2·h),and the respective N2O emission fluxes were in the ranges of-0.006 to 0.204 mg/(m2·h),0.012 to 0.161 mg/(m2·h),and 0.006 to 0.145 mg/(m2·h).Correlation analysis showed that humidity and the concentrations of total nitrogen,nitrite nitrogen,and COD were the primary factors influencing greenhouse gas emissions in IPRA system,and air temperature and pressure,and water temperature were the primary factors influencing greenhouse gas emissions in UPA system.The global warming potential(GWP)of the IPRA and UPA systems were 611.88 g/m2 and 1 112.45 g/m2,respectively,while the warming effects per unit of aquatic product were 561.36 g/kg and 1 002.21 g/kg,respectively,both showing UPA GHG＞IPRA GHG.Compared to UPA,IPRA reduced CO2 and CH4 emissions,but the difference in N2O emissions was negligible.In summary,the IPRA system significantly reduces greenhouse gas emissions during M.salmoides culture,making it an excellent low-carbon choice for aquaculture.