Noctiluca scintillans feeds on a large number of phytoplankton, including diatoms and dinoflagellates, and frequently forms a red tide in the East China Sea (ECS) and southern Yellow Sea (SYS). However, the spatiotemporal distribution pattern, controlling factors, and long-term change of N. scintillans in the ECS and SYS remain unclear. In the present study, we collected N. scintillans samples from the ECS and SYS throughout the four seasons of 2011. We sampled phytoplankton and environmental parameters simultaneously. The depth-integrated abundance (DIA) of N. scintillans was the highest and lowest in summer and winter, respectively. N. scintillans is distributed abundantly in eutrophic coastal waters and the Changjiang Estuary, which are characterized by high concentrations of phytoplankton and chlorophyll-a. A Spearman correlation test demonstrated that its DIA in the upper 30-m water column was generally more significantly associated with phytoplankton abundance and chlorophyll-a concentration than with temperature and salinity. The results of the generalized additive models revealed that chlorophyll-a concentration explained more of the variation in N. scintillans abundance than temperature and salinity throughout the year, particularly in warm seasons. These findings indicate that the seasonal and spatial changes of N. scintillans are largely regulated by phytoplankton biomass. Compared with the historical data from 1959 and 2002, the abundance of N. scintillans in the Changjiang Estuary increased considerably in 2011 with increasing phytoplankton abundance resulting from accelerated eutrophication and warming. These results clarify the controlling factors, red-tide formation mechanism, and changing trends associated with the N. scintillans in the ECS and SYS.

夜光虫以大量浮游植物为食，包括硅藻和甲藻，经常在东海（ECS）和黄海南部（SYS）形成赤潮。然而，时空分布格局、控制因素和长期变化N. scintillans在 ECS 和 SYS 中仍不清楚。在本研究中，我们收集了N. scintillans2011 年四个季节的 ECS 和 SYS 样本。我们同时对浮游植物和环境参数进行了采样。深度综合丰度（DIA）N. scintillans分别在夏季和冬季最高和最低。N. scintillans大量分布于富营养化的近岸海域和长江口，其特点是浮游植物和叶绿素含量高。一个. Spearman 相关性检验表明，其在上部 30 米水柱中的 DIA 通常与浮游植物丰度和叶绿素-一个浓度高于温度和盐度。广义加性模型的结果表明，叶绿素-一个浓度解释了更多的变化N. scintillans全年的温度和盐度都比温度和盐度要丰富，尤其是在温暖的季节。这些发现表明，季节和空间变化N. scintillans主要受浮游植物生物量的调节。与 1959 年和 2002 年的历史数据相比，N. scintillans2011 年长江口海藻数量显着增加，富营养化和变暖加速导致浮游植物丰度增加。这些结果阐明了与赤潮相关的控制因素、赤潮形成机制和变化趋势。N. scintillans在 ECS 和 SYS 中。