Journal of Tropical Oceanography ›› 2019, Vol. 38 ›› Issue (6): 9-20.doi: 10.11978/2019018CSTR: 32234.14.2019018

Special Issue: 南海专题

• Marine Ecology • Previous Articles     Next Articles

Distribution of Chlorophyll-a and its influencing factors in the northern South China Sea in summer

YANG Wei1,2,3, DONG Yuan2, ZU Tingting2, LIU Changjian3, XIU Peng2()   

  1. 1. University of Chinese Academy of Sciences, Beijing 100049, China
    2. State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
    3. South China Sea Marine Survey and Technology Center, State Oceanic Administration, Guangzhou 510300, China
  • Received:2019-02-21 Revised:2019-05-23 Online:2019-11-20 Published:2019-11-26
  • Contact: Peng XIU E-mail:pxiu@scsio.ac.cn
  • Supported by:
    Key Research Program of Frontier Sciences, CAS(QYZDJ-SSW-DQC022);National Natural Science Foundation of China(41576003);Natural Science Funds for Distinguished Young Scholar of Guangdong Province(2014A030306049);Natural Science Foundation of Guangdong Province(2017A030313251);Director Foundation of South China Sea Branch, State Oceanic Administration(1415);Director Foundation of South China Sea Branch, State Oceanic Administration(18106);100 Talents Program of The Chinese Academy of Sciences

Abstract:

Summer (from June to September) time series of 15 years (2002-2016) of chlorophyll-a (Chl a) from the Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua products were collected to discuss seasonal and interannual variability of ecological response of the Pearl River Plume in the Northern South China Sea (NSCS). In June, under the influence of southwest monsoon, nutrients from the Pearl River Delta were transported eastward to the shelf area, phytoplankton bloomed and Chla increased. The coverage area over the shelf in the NSCS reached the maximum in July, and decreased in August when the river discharge and wind reduced. In September when the northeasterly wind prevailed in the NSCS, the coverage area with high concentration of Chla (AHCHL) west of the estuary increased. Linear regression analysis suggested that the river discharge was the main reason for driving the AHCHL variability with a time lag of about one month. The combined effect of stronger (weaker) than the multi-year mean river discharge and wind resulted in extremely large (small) AHCHL in 2008 (2004). Because the spatiotemporal variability of Chl a in the NSCS was mainly influenced by the Pearl River Plume, the quality controlled satellite Chl a products can be used to discuss the variability of the Pearl River Plume.

Key words: Aqua/MODIS, Chlorophyll-a, Northern South China Sea, Pearl River Plume