We investigated phytoplankton production rates and grazing fates in the Costa Rica Dome (CRD) during summer 2010 based on dilution depth profiles analyzed by flow cytometry and pigments and mesozooplankton grazing assessed by gut fluorescence. Three community production estimates, from 14C uptake (1025 ± 113 mg C m-2 day-1) and from dilution experiments analyzed for total Chla (990 ± 106 mg C m-2 day-1) and flow cytometry populations (862 ± 71 mg C m-2 day-1), exceeded regional ship-based values by 2-3-fold. Picophytoplankton accounted for 56% of community biomass and 39% of production. Production profiles extended deeper for Prochlorococcus (PRO) and picoeukaryotes than for Synechococcus (SYN) and larger eukaryotes, but 93% of total production occurred above 40 m. Microzooplankton consumed all PRO and SYN growth and two-third of total production. Positive net growth of larger eukaryotes in the upper 40 m was balanced by independently measured consumption by mesozooplankton. Among larger eukaryotes, diatoms contributed ∼3% to production. On the basis of this analysis, the CRD region is characterized by high production and grazing turnover, comparable with or higher than estimates for the eastern equatorial Pacific. The region nonetheless displays characteristics atypical of high productivity, such as picophytoplankton dominance and suppressed diatom roles.

中文翻译：

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哥斯达黎加圆顶的浮游植物生产和放牧平衡

我们根据流式细胞仪分析的稀释深度剖面和肠道荧光评估的色素和中型浮游动物放牧，调查了 2010 年夏季哥斯达黎加圆顶 (CRD) 的浮游植物生产率和放牧命运。三个群落产量估计值，来自 14C 吸收（1025 ± 113 mg C m-2 day-1）和稀释实验分析的总 Chla（990 ± 106 mg C m-2 day-1）和流式细胞仪种群（862 ± 71 mg C m-2 day-1)，超过区域船基值 2-3 倍。微型浮游植物占群落生物量的 56% 和产量的 39%。与聚球藻 (SYN) 和更大的真核生物相比，原绿球藻 (PRO) 和微核生物的产量分布更深，但 93% 的总产量发生在 40 m 以上。微型浮游动物消耗了所有 PRO 和 SYN 生长以及总产量的三分之二。上部 40 m 中较大真核生物的正净增长通过中型浮游动物的独立测量消耗来平衡。在较大的真核生物中，硅藻对产量的贡献约为 3%。根据这一分析，CRD 地区的特点是产量高，放牧周转率高，与赤道东太平洋的估计值相当或高于估计值。尽管如此，该地区仍显示出非典型的高生产力特征，例如微型浮游植物占优势和硅藻作用受到抑制。与赤道东太平洋的估计值相当或更高。尽管如此，该地区仍显示出非典型的高生产力特征，例如微型浮游植物占优势和硅藻作用受到抑制。与赤道东太平洋的估计值相当或更高。尽管如此，该地区仍显示出非典型的高生产力特征，例如微型浮游植物占优势和硅藻作用受到抑制。