| The Asian dust affecting the the growth of phytoplankton in marine environment was studied through twice spot mesocosm experiments and three times of laboratory stimulated experiments.It can be seen from the dissolution of dust test that the dissolved nutrients from Beijing and Qingdao dust were obviously higher than the dust from source. Beijing and Qingdao dust Dissolution of various nutrients in the time-dependent rate were significantly higher than the source dust. 48 h after the dissolution, the concentration of Fe levels in the dissolution were different, the dust sample from Xilingele Meng ZhengLan Banner in Inner Mongolia has the highest concentration, to 3.4μg·L-1·g-1, the dust sample from Alashan Meng Jilantai in Inner Mongolia has the lowest, to 0.2μg·L-1·g-1.The experiments results of Yellow Sea ship-based spot mesocosm in April 2006 showed that different addition of nitrogen nutrients had significant effect on the growth of Phytoplankton. NH4-N added was the highest, which specific growth rate of Phytoplankton reached 0.26 d-1, the NO3-N and dusts added was the lowest, which specific growth rate of Phytoplankton reached 0.15 d-1, lower than the only equal dust added (0.23d-1). The specific growth rate of mesocosm Phytoplankton with dust added (0.12 d-1)was higher than the control (0.10d-1), which concluded that the addition of dust had some enhancement to the growth of mesocosm Phytoplankton, but not obviously.By adding dust to inshore waters and ocean, Dust affecting the growth of Thalassiosira rotula was compared under different addition amount of dust and different seawater medium. The results shows that the promotion of dust to the growth was different for diverse water medium. In inshore waters, the promotion of dust addition was smaller. In ocean, dust addition could significantly promote the growth of Phytoplankton due to the low concentration of nutrient salt. Dust addition amount also had obvious effect on the growth of Thalassiosira rotula with oligotrophic ocean water. The specific growth rate of Thalassiosira rotula was raised by the increasing dust addition.During the lab experiments of relationship between Asian dust and growth of several marine microalgaes, five different source dust affecting the three kinds of microalgaes growth were compared. It conclude that in oligotrophic ocean water, all dust had significant promotion to the growth of Chaetoceros curvisetus, Chaetoceros minutissimus and Prorocendrum donghaiense. But in eutrophic ocean water, none of the dust had influence on growth. Under oligotrophic condition, the dust sample from Qingdao Fu hill had high promotion to all three microalgaes, especially to Chaetoceros minutissimus. The dust sample from Xilingele Meng ZhengLan Banner in Inner Mongolia on the growth of three kinds of microalgae also have a high role in promoting, in view of its higher soluble Fe content.Concentration of nutrient salt and soluble Fe in Dust from sandstorm settlement and source were different. In 2007, dust from Inner Mongolia source and Beijing spring sandstorm were collected, used to culture the natural Phytoplankton in the coastal sea of Jiaozhou Bay of Qingdao. Results showed that under high dust addition, the promotion to the growth of dust from Beijing was clearly higher than dust from Inner Mongolia. But under low addition, both of them had slight promotion to the Phytoplankton. All the mesocosm showed that the proportion of nano-Phytoplankton rised and Pico- Phytoplankton reduced gradually at the point of structure change of Chlorophyl a. The extents of change were different with diverse dust addition. Phytoplankton in the use of ammonium nitrate was priority to nitrate nitrogen.The consumption of silicate by Diatom which was the dominant species of Phytoplankton made the concentration of silicate in mesocosm reduced constantly. Mesocosm added with 360mg Beijing dust had obvious ammonium nitrate content, this may related to its higher Chlorophyl a than others.
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