渤海海峡冬季无机碳的立体分布特征及其源汇变化

根据2010年2月至2010年3月对渤海海峡3个断面39个站位表层、10 m层和30 m层水体中盐度、水温、叶绿素a以及无机碳等参数的测定数据,分析了该季节溶解无机碳的分布特征以及源汇变化状况,探讨了影响其分布的主要因素。结果显示,调查期间渤海海峡水体中各水层溶解无机碳(DIC)及其组分浓度分布较一致,其中DIC及HCO₃-的浓度等值线分布均呈现出从西南向东北梯度降低的趋势,且受温度影响明显;二氧化碳分压[p(CO₂)]则表现出与叶绿素a含量成明显负相关的分布特征;位于渤海海峡东部的H断面垂直方向上,由于受黄海、渤海水团在海峡中部交汇混合形成的水体紊流影响,DIC及其组分在断面中部等值线分布较两边曲折。冬季渤海海峡表现出明显的源、汇分区分布特征,整个调查区海-气二氧化碳通量为3.52 mmol/(m2·d),表现为大气CO₂的弱源。冬季流经渤海海峡的DIC通量约为(130±2)×103 mol/s。

Distribution characteristics and source/sink changes of dissolved inorganic carbon around the Bohai Strait in winter

The field observation was carried out in Febuary 2010 to March 2010. A total of 39 stations was established three transects. Based on the data collected, the composition and distribution of dissolved inorganic carbon(DIC) were examined in 0 m, 10 m, 30 m depth and H Section. The results showed that the concentration of DIC and it's parameters in each depth were similar. The concentration of DIC and HCO₃^- decreasing from southwest to northeast. Temperature has important influence on the distribution of DIC and HCO₃^-. The relationship between p(CO₂) and chlorophyll-a was negative. In H section, the distribution of DIC and it's parameters of middle section were more complicated than the other section. The CO₂ flux at the Bohai Strait was 3.52 mmol/(m²·d), which shows that this area was the source of CO₂ in winter. The DIC flux flowed from the Bohai Strait was (130±2)×10³ mol/s.