Chin J Plant Ecol

   

Species distribution pattern and its underlying mechanism of mangrove plants around the South China Sea

Xin Yang1,Ming-Xun REN   

  • Received:2022-09-09 Revised:2022-10-17 Online:2022-10-18 Published:2022-10-18
  • Contact: Ming-Xun REN

Abstract: Aim The region around the South China Sea is a relatively independent geographical unit, which can be divided into eight areas, i.e. South China, Hainan Island, Taiwan Island, Indochina Peninsula, Malay Peninsula, Borneo, Palawan Island, and Luzon Island. The region around the South China Sea is rich of mangrove plants worldwide, locating between south China and Southeast Asia and thus is a key region for understanding the historical connection and evolutionary trend of the flora of south China and Southeast Asia. Method Species richness of mangrove in the region around the South China Sea and other regions worldwide were obtained through extensive literature survey and mapped with Arc Map. Species distribution pattern of four typical mangrove taxa, i.e. Rhizophoraceae, Malvaceae, Sonneratia, Avicennia, were determined with 1°×1° grid by DIVA-GIS 7.5.0. The dispersal history and routes and its main affecting factors were explored through literature survey in ISI Web of Science. Important findings There are 39 species of true mangroves and 14 species of semi-mangroves distributed in this region, mostly distributed in Malay Peninsula, Borneo, Hainan Island, Indochina Peninsula, Luzon Island. All mangrove species are widespread in the region. This may be because the South China Sea has completely different ocean current directions in summer and winter, promoting long-distance dispersals of mangrove plants. There is a certain internal circulation in the northern and southern parts of the South China Sea, and resulting in the appearance of relatively isolated genetic lineages on both sides of the line connecting Cam Ranh Bay and the northern tip of Palawan Island, especially for the true mangrove such as Excoecaria agallocha, Lumnitzera racemose, and Aegiceras corniculatum. The sea level in the Pleistocene decreased by about 120 m, which profoundly affected the distribution pattern and migration route of mangroves in the region. Phylogeographical studies using updated molecular technology, especially genomic data, is suggested to reveal the dispersal history of mangrove plants and their future evolutionary trend under the influence of global climate change.

Key words: species diversity, long-distance dispersal, ocean currents, monsoon, species differentiation