BENTHIC FORAMINIFERA IN THE SURFACE SEDIMENTS OF THE MINNAN-TAIWAN BANK REGION AND ITS ENVIRONMENTAL CHARACTERISTICS

In the present paper 37 samples collected from the surface sediments of the Minnan-Taiwan Bank were analyzed. In all 328 benthic foraminiferal species belonging to 132 genera are identified . According to their composition and distribution, six benthic foraminiferal fauna can be established:Ⅰ. Ammobacuities formoensis-Arenoparrella asiatiea fauna ; Ⅱ. Quinqueloculina centrostriata-Textularia foliacea fauna; Ⅲ. Pararotalia ozawai-Poroeponides lateralis fauna, it can be divided into two groups (Ⅲa andⅢb);Ⅳ. Cibicides lobatulus-Hanzawoaia mantaensis fauna, two groups (Ⅳa and Ⅳb) can be identified;Ⅴ . Robulus calcar-Gyroidina neosoldanii fauna; Ⅵ. Ammonia parkinsonina-Elphidium advenum fauna. In the Ⅲa, Ⅲb and ⅣFa fauna, every station,has identical dominant species which numbers make up the first three places. However , the Ⅰ and Fb fauna are defined by the range of some species only found in these area. There are different characteristics of environment in every fauna. Along with the water depth, the salinity and hydrodynamics are the important controlling factors for distribution of benthic foraminifera. At station 303 located in the southwest of the Taiwan Bank, both distribution of benthic foraminifera and sediments are found evidently different from the adjacent area with similar depth . It might be resulted by the influence of upwelling which exists in this area over a long period of time.