Journal of Tropical Oceanography ›› 2024, Vol. 43 ›› Issue (3): 72-86.doi: 10.11978/2023081cstr: 32234.14.2023081

• Marine Biology • Previous Articles     Next Articles

Community structure of reef-building corals and their environmental impact factors in the coastal waters of Hongpai-Maniao, Lingao, Hainan

LUO Yong1,2,3(), HUANG Lintao1,4, YANG Jianhui1, LIAN Jiansheng1,2,3, LIU Chengyue1,2,3, JIANG Lei1,2,3, LIANG Yuxian1, CHEN Lunju1, LEI Xinming1,2,3, LIU Sheng1,2,3, HUANG Hui1,2,3()   

  1. 1. Laboratory of Tropical Marine Bio-resources and Ecology (South China Sea Institute of Oceanology, Chinese Academy of Sciences), Guangzhou 510301, China
    2. CAS-HKUST Sanya Joint Laboratory of Marine Science Research, Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, SCSIO, Sanya 572000, China
    3. Sanya National Marine Ecosystem Research Station; Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya 572000, China
    4. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2023-06-15 Revised:2023-07-22 Online:2024-05-10 Published:2024-06-04
  • Supported by:
    National Natural Science Foundation of China(41976120); National Natural Science Foundation of China(42276124); National Key Research and Development Program(2021YFC31005001); Natural Science Foundation of Hainan Province(423MS130)

Abstract:

To identify the community structure of reef-building corals and their environmental factors in the coastal waters of Hongpai-Maniao, Lingao, Hainan, a survey on the reef-building coral communities, substrate types, sediment accumulation rates and water environmental factors was conducted in the region from 18th to 23th March, 2023. The results showed that: 1) reef-building corals in the region were identified with 42 species in 24 genera of 13 families and 7 undetermined species, with a mean cover of (18.05±10.53)%, concentrated at water depths of 1.0~2.5m; 2) the dominant species of reef-building corals were predominantly massive or encrusting growth types, and dead reef-building coral cover (> 2 years old) was significantly negatively correlated with live reef-building coral cover and Shannon's diversity index, while Shannon's diversity index was significantly positively correlated with Simpson's dominance index and Pielou's evenness index, indicating that the death of reef-building corals was accompanied by a significant reduction in their cover and species diversity; 3) dead reef-building coral cover was significantly positively correlated with sand cover and negatively correlated with pH; the Pielou's evenness index was significantly negatively correlated with dissolved oxygen and sediment accumulation rates; water turbidity was significantly positively correlated with the diffuse attenuation coefficient of the photosynthetically active radiation (Kd-PAR) and its mean value (3.81±1.10) NTU (nephelometric turbidity unit) already exceeded the stress threshold of 3NTU affecting the growth of reef-building corals. These results demonstrate that benthic sand cover, sedimentation rate, turbidity, pH, dissolved oxygen and Kd-PAR are important environmental factors affecting the structure of reef-building coral communities in this area. In summary, the coastal waters of Lingao Hongpai-Maniao is one of the hotspots for the distribution of reef-building corals, with high species diversity and cover. However, the vertical distribution of reef-building corals in this region is narrow and is under stress from multiple environmental factors, requiring effective measures for timely protection.

Key words: Lingao, reef-building corals, community structure, environmental factors, impacts