This is one of a series study on yellow substance in seawater.Based on the results of experiment

the distribution on fluorescence relative intensity of yellow substance in China Sea area is obtained firstly by using the fluoricence.The distribution on fluorescence intensity in Jiaozhou Bay is as following

The fluorescence intensity of yellow substance is the highest

more than over 7.5 *10 -7

along the northern and western shore especially in the river estuary.It decreases in the central area of the Bay

and reaches the lowest in the outside mouth of the Bay.There is a clear differentce in yellow substance between the inner and the exterior of the Bay.The fluorescence intensity of yellow substance is uneven in the Jiaozhou Bay

and its distribution is relatively close to the rivers along the shore.It is suggested that the yellow substance in the Jiaozhou Bay is originated from the land

carried by the rivers to the Bay.