Journal of Geographical Sciences ›› 2021, Vol. 31 ›› Issue (11): 1655-1674.doi: 10.1007/s11442-021-1916-y

• Special Issue: Fluvial and Geomorphological Features • Previous Articles     Next Articles

Substrate damage and recovery after giant clam shell mining at remote coral reefs in the southern South China Sea

ZHOU Shengnan1,2,4(), SHI Qi2,1,*(), YANG Hongqiang2,1,3, ZHANG Xiyang2,1, LIU Xiaoju1,2,4, TAN Fei1,2,4, YAN Pin2,1   

  1. 1. Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, CAS, Guangzhou 510301, China
    2. Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
    3. Nansha Marine Ecological and Environmental Research Station, CAS, Sansha 573199, Hainan, China
    4. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2020-01-04 Accepted:2021-08-12 Online:2021-11-25 Published:2021-11-25
  • Contact: SHI Qi E-mail:zhousn@scsio.ac.cn;shiqi@scsio.ac.cn
  • About author:Zhou Shengnan (1993‒), PhD Candidate, specialized in coral reef geomorphology and environment. E-mail: zhousn@scsio.ac.cn
  • Supported by:
    Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0206);Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0104);National Science & Technology Fundamental Resources Investigation Program of China(2018FY100103);The Strategic Priority Research Program of the Chinese Academy of Sciences(XDA13010103);Special Support Program for Cultivating High-level Talents in Guangdong Province(2019BT02H594);National Natural Science Foundation of China(41776128);National Natural Science Foundation of China(U1901217)

Abstract:

Giant clam shell mining (GCSM), a unique phenomenon occurring at remote coral reefs in the southern South China Sea (SCS), forms striking scars on the reef flats and damages the reef flat substrate. Through image analyses at three times (2004.02.02, 2014.02.26, and 2019.04.10) and in situ surveys at Ximen Reef, a representative site that has experienced GCSM, we quantified the GCSM-generated substrate damage and the corresponding recovery. GCSM was estimated to have occurred sometime between 2012 and 2014, causing reduction in live coral subarea and formation of micro-relief as trenches and mounds. GCSM-generated damage was restricted to the reef flat. After GCSM, coral and algae subarea increased, and the trenches and mounds tended to be filled and eroded, representing a natural recovery of the substrate. The legal prohibition on human disturbances at the coral reefs contributed to substrate recovery at Ximen Reef. This case also implied that recovery of the other coral reefs that suffered from GCSM is possible.

Key words: giant clam shell mining, substrate components, micro-relief, reef flat, South China Sea