热带海洋学报 ›› 2025, Vol. 44 ›› Issue (2): 18-29.doi: 10.11978/2024095CSTR: 32234.14.2024095

• 海洋水文学 • 上一篇    下一篇

基于水文气象参数的南海西部叶绿素a估算*

郑媛宁1,2(), 李彩1(), 周雯1, 许占堂1, 施震1, 张现清1,2, 刘聪1,2, 赵金成1,2   

  1. 1.热带海洋国家重点实验室(中国科学院南海海洋研究所), 广东 广州 510301
    2.中国科学院大学, 北京 100049
  • 收稿日期:2024-04-26 修回日期:2024-06-19 出版日期:2025-03-10 发布日期:2025-04-11
  • 通讯作者: 李彩
  • 作者简介:

    郑媛宁(1999—), 女, 河南省邓州市人, 硕士研究生, 研究方向是海洋环境监测。email:

    *感谢国家自然科学基金共享航次, 感谢中国科学院南海海洋研究所海洋光学学科组全体成员对于本次实验数据获取做出的贡献。

  • 基金资助:
    广东省基础与应用基础研究基金项目(2023A1515240073); 广州市南沙区科技规划项目(2022ZD001); 国家重点研发计划项目(2016YFC1400603); 国家重点研发计划项目(2017YFC0506305)

Estimation of Chlorophyll-a in the western South China Sea based on hydro-meteorological parameters*

ZHENG Yuanning1,2(), LI Cai1(), ZHOU Wen1, XU Zhantang1, SHI Zhen1, ZHANG Xianqing1,2, LIU Cong1,2, ZHAO Jincheng1,2   

  1. 1. State Key Laboratory of Tropical Oceanography (South China Sea Institute of Oceanology, Chinese Academy of Sciences), Guangzhou 510301, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2024-04-26 Revised:2024-06-19 Online:2025-03-10 Published:2025-04-11
  • Contact: LI Cai
  • Supported by:
    Guangdong Basic and Applied Basic Research Foundation(2023A1515240073); Science and Technology Planning Project of Science and Technology Planning Project of Nansha District, Guangzhou(2022ZD001); National Key Research and Development Program of China(2016YFC1400603); National Key Research and Development Program of China(2017YFC0506305)

摘要:

文章以叶绿素a (Chlorophyll-a, Chl-a)的低成本、高精度估算为目标, 利用近十年南海西部调查航次数据, 基于随机森林(random forest, RF)算法, 以水文气象条件的变化对海洋生化过程的影响及贡献为基础, 以水文气象参数(hydro-meteorological parameters, HMPs)作为输入数据, 构建Chl-a的低成本估算模型对南海西部表层Chl-a进行了估算。为验证基于水文气象参数估算Chl-a的可靠性, 利用准分析算法(quasi-analytical algorithm, QAA)以实测固有光学特性参数为基础, 推导得到原位遥感反射率(remote sensing reflectance, Rrs)。在此基础上, 结合海洋颜色4 (ocean color 4, OC4)、Aiken和Tassan等经典水色产品经验算法对 Chl-a进行了估算及评价, 评价结果表明OC4算法的估算精度最高, R2可达0.438。与RF模型0.568的R2比较不难看出, 得益于HMPs的大数据量, 基于HMPs的RF模型其Chl-a估算结果表现出较为优秀的稳定性和泛化性, 与实测结果的空间分布一致性更好。通过对特征参数重要性进行研究发现, 盐度是基于HMPs估算Chl-a的机器学习模型中最重要的特征变量, 其次依次是温度、风与气压, 贡献率最低的是相对湿度。

关键词: 叶绿素a, 水文气象, 机器学习, 南海

Abstract:

With the goal of low-cost and high-accuracy estimation of Chlorophyll-a (Chl-a), a model for estimating Chl-a in the surface layer of the Western South China Sea (WSCS) was constructed in this study. Using the data from the WSCS cruises in the past ten years, and based on the influence of changes of hydro-meteorological conditions and their contribution to the oceanic biochemical processes, the hydro-meteorological parameters (HMPs) were used as the input data of the random forest (RF) algorithm. To evaluate the reliability of estimating Chl-a based on HMPs, the quasi-analytical algorithm (QAA) was used to derive the in-situ remote sensing reflectance (Rrs) based on the measured inherent optical property parameters. Then Chl-a was estimated and evaluated by the combination of classical empirical algorithms for water color products such as Ocean Color 4 (OC4), Aiken and Tassan, and the evaluation results showed that the OC4 algorithm had the highest estimation accuracy, with an R2 of up to 0.438. The comparison with the R2 of 0.568 of the RF-based model shows that, owing to the large data volume of HMPs, the Chl-a estimation results of the RF model based on HMPs show much better stability and generalization, and better spatial distribution consistency with the measured results. It was found in study of the importance of feature parameters that in the machine learning model for estimating Chl-a based on HMPs, salinity is the most important feature variable, followed in turn by temperature, wind and air pressure, and the lowest contributor is relative humidity.

Key words: Chlorophyll-a, hydro-meteorology, machine learning, South China Sea

中图分类号: 

  • P731.3