闽江河口养虾塘养殖期和非养殖期CO2通量变化特征

为揭示河口区陆基养虾塘从养殖期到非养殖期一年间的CO₂通量变化，以福建省闽江河口鳝鱼滩陆基养虾塘为研究对象，于2016年5月-2017年3月采用悬浮箱/静态箱-气相色谱法对养虾塘养殖期水-大气界面和非养殖期沉积物-大气界面白天CO₂垂直通量进行原位观测.结果表明:①养虾塘在整个研究期间CO₂通量变化范围为-62.87~162.81 mg/（m2·h），平均值为（42.66±18.12）mg/（m2·h），总体上表现为大气CO₂的释放源，且呈非养殖期CO₂通量平均值（78.51±16.61）mg/（m2·h）]显著高于养殖期（17.98±18.26）mg/（m2·h）]的特征.②养殖期间，养虾塘CO₂通量呈"排放-吸收"交替变化的特征，而非养殖期养虾塘一直是大气CO₂的净排放源.③养虾塘养殖期CO₂通量时间变化特征主要受到ρ（DOC）（DOC为总溶解有机碳）、ρ（SO₄2-）、ρ（Cl-）、盐度、pH、ρ（Chla）（Chla为叶绿素a）的影响，其中，pH和ρ（SO₄2-）是其主要影响因子，而ρ（TDN）（TDN为总溶解氮）、ρ（TDP）（TDP为总溶解磷）、ρ（SO₄2-）对非养殖期CO₂通量时间变化影响较大.研究显示，滨海陆基养殖塘是大气CO₂的重要来源，其排放通量多低于河流、水库等水生生态系统，但高于湖泊生态系统；养殖塘CO₂通量受人为影响明显，其较高的变异性与养殖生物、饲料投放以及浮游藻类有关. 

Temporal Variation of Carbon Dioxide Flux between Farming and Non-Farming Stages in the Land-Based Shrimp Pond in the Min River Estuary

Coastal land-based aquaculture ponds are special artificially managed aquatic ecosystem in the world. However, the temporal variation and the change in source and sink function of the CO₂ fluxes in the coastal shrimp ponds during the farming phase and non-farming phase have not been clarified. The CO₂ fluxes at the water-atmosphere interface during the farming phase and at the sediment-atmosphere interface during the non-farming phase in a land-based shrimp pond were measured by the static chamber and floating chamber method from May 2016 to March 2017 in the Shanyutan of the Min River estuary, southeast China. The CO₂ flux of the shrimp pond ranged from -62.87 to 162.81 mg/(m2·h) at annual scale, with a mean value of (42.66±18.12) mg/(m2·h). The shrimp pond was a source of atmospheric CO₂. Moreover, the CO₂ flux during the non-farming phase ((78.51±16.61)mg/(m2·h)) was significantly higher than that in the farming phase ((17.98±18.26)mg/(m2·h)). During the culture period, the CO₂ flux showed the characteristic of 'emission-absorption' alternation. In the non-farming phase the shrimp pond became a net CO₂ source. The CO₂ flux in the culture period was mainly affected by DOC, SO₄2-, Cl-, salinity, pH, and Chla, and pH and SO₄2- were the main influencing factors. TDN, TDP, and SO₄2- had a great influence on the CO₂ flux during the non-farming phase. Our findings suggested that aquaculture shrimp ponds are important source of atmospheric CO₂, and their effluxes are generally lower than that from the rivers, reservoirs and other aquatic ecosystems, but are higher than lakes. The CO₂ flux in the aquaculture pond is obviously affected by human activities. The large temporal variation is related to aquaculture organisms, feed delivery and planktonic algae.