Study on the dominant species of Pteropoda in East China Sea

摘要

Based on the data of four seasonal marine surveys in the East China Sea (23°30'-33°N,118°30'-128°E )during 1997-2000, the author studied the ecological characters of dominant Pteropoda species in the area. Results showed that there were five dominant Pteropoda species, more in summer, less in autumn and even in other seasons. These species, though belonging warm water species, can be categorized into two different groups in habitability. The first group was adapted in summer and autumn, including Creseis acicula, Desmopteruspapilio and Creseis virgule, while the second group in winter and spring, represented by Limacina trochiformis and Agadina syimpsoni. The first group was more abundant than the second one.Besides, the first group contributed more to the Pteropoda abundance having higher occurrence frequency and aggregation intensity than the second. In horizontal distribution, the first group species reside in nearshore, and they could migrate to shallow place near estuary and aggregated in high density, while the second one was different: lower abundance, less occurred and aggregated because they were halophilic warm water species, and they were usually abundant in offshore area.