Abstract: A two-factorial experiment was designed to study the effects of temp erature (10, 15, 20, and 25 ℃) and light intensity (20, 60, 100, 140, and 180 μE·m-2·s-1) on the growth and biochemical composition of Sargas sum thunbergii. The results showed that temperature, light intensity, and thei r interactions had significant effects on the growth of S. thunbergii. A hig her growth rate of S. thunbergii was observed at 15 ℃〖KG-*2〗-〖KG-*7〗20 ℃, and, with the increase of temperature, the light intensity for the maximum grow th rate of S. thunbergii had an increasing trend. At 10 ℃ and 15 ℃, higher li ght intensity had definite inhibition effect on the growth of S. thunbergii; while at 20 ℃ and 25 ℃, the growth rate was generally increased with increasing light intensity. Both temperature and light intensity had significant effects on the chlorophyll a and fucoxanthin contents of S. thunbergii, and the effect s of light intensity was greater than those of temperature. In general, the chlo rophyll a and fucoxanthin contents of S. thunbergii decreased significantly with increasing light intensity but increased with increasing temperature. The c arbohydrate content of S. thunbergii increased with increasing light intensi ty, while no significant difference was observed at different temperature. The p rotein content of S. thunbergii decreased with increasing light intensity, a nd was higher at 10 ℃ and 15 ℃ but tented to decrease with increasing temperature . The variation of light intensity and temperature induced the changes in the bi ochemical composition of S. thunbergii, and these changes could be an active physiological adjustment for the adaptation to the variation of environmental f actors, which was of ecological significance to the growth and survival of S. thunbergii.

Key words: Hangjin Banner., remote sensing ecological index, ecological environment quality