文献类型：期刊文献

英文题名：Long-term declining trend of phytoplankton bloom area in the upwelling zone of the northeastern South China Sea under climate variability

作者：Chen, Ying[1,3,4];Zhao, Hui[1,2,3,4]

机构：[1]Guangdong Ocean Univ, Coll Chem & Environm Sci, Zhanjiang, Peoples R China;[2]Southern Marine Sci & Engn Guangdong Lab Zhuhai, Zhuhai, Peoples R China;[3]Guangdong Ocean Univ, Res Ctr Coastal Environm Protect & Ecol Resilience, Zhanjiang, Peoples R China;[4]Guangdong Ocean Univ, Cooperat Res Ctr Nearshore Marine Environm Change, Zhanjiang, Peoples R China

年份：2025

卷号：269

外文期刊名：OCEAN & COASTAL MANAGEMENT

收录：SCI-EXPANDED(收录号：WOS:001522853600002)、、EI(收录号：20252618663513)、Scopus(收录号：2-s2.0-105008813757)、WOS

基金：This work was supported by the National Natural Science Foundation of China (No. 42076162) ; the Graduate Practice Innovation Ability Enhancement Plan Cultivation Project of Guangdong Ocean University (No.10) ; the project supported by Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) (No. 311020004) ; and the Postgraduate Education Innovation Project of Guangdong Ocean University (202428) .

语种：英文

外文关键词：Phytoplankton bloom area; EEMD decomposition; Random forest regression model; Sea surface temperature; Sea surface wind

外文摘要：In recent years, global ocean warming has intensified stratification, suppressing upwelling-driven nutrient transport and impacting phytoplankton growth. This study analyzes 22-year data from the northeastern South China Sea upwelling system using Ensemble Empirical Mode Decomposition (EEMD) and lag correlation to reveal multiscale drivers of phytoplankton bloom area dynamics. Results show a significant decline in phytoplankton bloom area over the past 22 years. The EEMD decomposition shows that the semiannual component strongly correlates with winter wind speed (r = 0.57, p < 0.01), while the seasonal component exhibits a robust negative correlation with sea surface temperature (SST) (r = -0.83, p < 0.01), indicating that the rise in SST inhibits the expansion of phytoplankton bloom area by limiting the vertical transport of nutrients. Interannual and decadal components show delayed negative correlations with the Multivariate ENSO Index (2-3 year lag, r = -0.30) and Pacific Decadal Oscillation (4-year lag, r = -0.94), highlighting climate modes' long-term regulation. Based on the EEMD results, we incorporated the key controlling factors into a Random Forest regression model, which demonstrates high predictive accuracy (training R-2 = 0.92, testing R-2 = 0.75), effectively capturing phytoplankton bloom area variability. This work elucidates multiscale controls on upwelling ecosystem productivity under climate change, providing critical insights for marine ecological assessments.