Sargassum beds in Gouqi Island,Zhejiang Province,are the target researching sea area in this paper.Based on the uptake experiments of Sargassum horneri(Turn.) Ag.on inorganic phosphate,silicate,nitrite and nitrogen,the fluctuation of the uptake rate in 80 hours is analyzed :the uptake rate of inorganic phosphate decreases with time exponentially;the uptake rate of silicate decreases with time linearly;the uptake rate of nitrite increases with time logarithmically and is suppressed at the initial stage;Sargassum horneri(Turn.) Ag.absorbs nitrogen as N nutrient preferentially.Based on the uptake experiment of Sargassum horneri(Turn.) Ag.on silicate with gradient biomass of Sargassum horneri(Turn.) Ag.and initial silicate consistency,the fluctuation and the correlation factors of the silicate consistency and the dissolve rate of the silicate in seawater and the uptake rate of the Sargassum horneri(Turn.) Ag.on silicate are analyzed: the fluctuation of silicate in 10 days correlates with oriental silicate consistency,and doesn't correlate with biomass of Sargassum horneri(Turn.) Ag.;the fluctuation of the fierce degree of silicate consistency in seawater correlates with both biomass of Sargassum horneri(Turn.) Ag.and oriental silicate consistency.