Photosynthesis‐irradiance (P‐E) parameters, such as the maximum photosynthetic rate () and maximum light utilization coefficient (α), are key parameters of primary production (PP) models. It is necessary to understand the response of P‐E parameters to mesoscale eddies to accurately model PP in eddies. The P‐E parameters and phytoplankton communities were examined at the surface and the deep chlorophyll maximum (DCM) of the eddy dipole in the western South China Sea. The surface differed significantly between the edge and center of both eddies. The at the center was significantly higher than that at the edge of the cyclonic eddy (CE), while the opposite trend was observed in the anticyclonic eddy (AE). Phytoplankton community composition modulated variability in P‐E parameters in the eddy dipole. Over 75% of the variance in surface P‐E parameters could be explained by the pico‐phytoplankton communities and environmental factors (nutrients and temperature). In contrast, the ratio of Synechococcus abundance to chlorophyll a concentration was primarily responsible for the variability in P‐E parameters at the DCM. These relationships allowed us to model and α at all stations and depths sampled. The integrated primary production (IPP) determined from these modeled P‐E parameters was coincident with the IPP determined from on‐deck incubations. The modeled ‐α‐based IPP exhibited a higher IPP at the CE center than that at the AE center. Our findings can improve the parameterization of the physical‐biogeochemical coupling models of eddies.

中文翻译：

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南海西部涡流偶极子的光合作用-辐照度响应

光合作用辐照度（P‐E）参数，例如最大光合速率（）和最大光利用系数（α），是初级生产（PP）模型的关键参数。有必要了解P-E参数对中尺度涡旋的响应，以准确地模拟涡旋中的PP。在南海西部的涡旋偶极子的表面和深部叶绿素最大值（DCM）处检查了P‐E参数和浮游植物群落。两个涡流的边缘和中心之间的表面差异很大。这中心的旋风比旋风涡（CE）的边缘显着高，而反气旋的旋风（AE）则观察到相反的趋势。旋涡偶极子中P-E参数的浮游植物群落组成调节变异性。浮游植物的浮游生物群落和环境因素（养分和温度）可以解释超过75％的表面P-E参数变化。相比之下，Synechococcus丰度与叶绿素a浓度之比主要是导致DCM的PE参数变化的主要原因。这些关系使我们能够模型和α在所有采样站和深度进行采样。通过这些建模的P-E参数确定的综合初级生产（IPP）与通过甲板上孵化确定的IPP一致。建模- α为基础的在IPP在AE中心CE中心比表现出更高的IPP。我们的发现可以改善涡旋的物理-生物地球化学耦合模型的参数化。