Biodiv Sci ›› 2006, Vol. 14 ›› Issue (6): 508-516.  DOI: 10.1360/biodiv.060066

• 论文 • Previous Articles     Next Articles

Causal analysis on diversity of medusa in the East China Sea

Zhaoli Xu1*, Mao Lin2   

  1. 1 Key and Open Laboratory of Marine and Estuary Fisheries, Ministry of Agriculture of China, East China Sea Fisheries Research Institute, Chinese Academy of Fisheries Sciences, Shanghai 200090, China
    2 The Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China
  • Received:2006-03-28 Revised:2006-09-25 Online:2006-11-20 Published:2006-11-20
  • Contact: Zhaoli Xu

Abstract: Based on the maritime data collected from 23°30′–33°00′ N and 118°30′–128°00′ E of the East China Sea in four seasons during 1997–2000, we analyzed the dynamics of medusa diversity and the causes. A total of 103 medusa species were observed, which were mainly distributed in southern and northern offshore of the East China Sea. Higher species diversity indices (H′) of medusa occurred, respectively, in the southern part of the sea, offshore, and in summer and winter. The number of species was closely correlated with H′ value, whereas the abundance was not correlated with it significantly. The lower H′ value nearshore in spring and autumn resulted from the aggregation of Muggiaea atlantica nearshore of Zhejiang Province and Diphyes chamissonis at the Yangtze River estuary. Water temperature, followed by salinity, was main environmental factor influencing the distribution of species diversity. H′ value was related to the water temperature of 10 m layer in winter and spring, while it is associated with surface water temperature in summer and with 10 m-salinity-layer in autumn. The isoline distribution of H′ value reflected the direction of currents and changes in water masses in the East China Sea, the H′ isoline was a good indicator for analyzing the East Sea cold masses.