ABSTRACT

Large amorphous aggregates, called “NUTA” (Japanese fisherman's jargon), were collected during 1986-1988, using a NUTA trap system in Osaka Bay, the Seto Inland Sea. These particles adhere to mooring ropes and fishing nets. To clarify the nature and distribution of NUTA, this study determined the organic matter composition of NUTA and those of suspended and sinking particles. The results revealed that the nature and distribution of NUTA are different from those of suspended particles. For example, the C/ATP and C/Chla ratios of NUTA were several times higher than those of the suspended particles. Cluster analysis of the amino acid composition of three types of particles showed that NUTA were more similar to sinking particles than to suspended particles. It can be considered that NUTA are formed by the decomposition of phytoplankton into detritus.