GUANGZHOU, Aug. 6 (Xinhua) -- Chinese scientists said on Thursday that they have completed a comprehensive scientific expedition near Zhongsha Islands in the South China Sea.

During the expedition project, which came to an end in late July, three research vessels were organized for missions including samplings for topographic, hydrodynamic, meteorological, chemical, ecological, and biological research in different water areas near the islands, according to the South China Sea Institute of Oceanology of the Chinese Academy of Sciences.

Underwater geological drilling was also carried out at the big atoll, a ring-shaped coral reef of Zhongsha.

Lin Qiang, the chief scientist of the project, said the expedition has laid a more solid foundation for the study of the ecological environment and biological resources, the fine topographic mapping of the water areas near Zhongsha Islands, and an accurate understanding of stratum features of the islands and reefs in the area.