| Inner-source loading was a key factor to influence the ecosystem of shallow lake, it played an important role after the outer-source loading was removed. Sediment resuspension was the major method of inner-source release induced by wind or fish predation. In this study, we try to quality the effect of an ecological engineering on sediment resuspension with sediment trap, seston and surface sediment, and discuss the influence of sediment resuspension on nutrient structue in water column. The results suggest that the ecological engineering can reduced the sediment resuspension effectively. As a classical large shallow lake, Taihu Lake is suffered from the wind-induced wave and sediment is brought into water column. During the study period, the sediment resuspension rate was 804.49 g dw m-2 d-1 (293.64 kg m-2 a-1) in the pelagic zone(E zone), while in B zone (protected by wave-eliminated engineering) and A zone (protected by wave-eliminated engineering and enclosure) the sediment resuspension ratewas 293.27 g dw m-2 d-1 (107.05 kg m-2 a-1, 36.50% of E zone) and 134.67 g dw m-2 d-1 (49.15 kg m-2 a-1, 16.75% of E zone) . With resuspension 1664.29 mg N m-2 d-1 and 633.06mg P m-2 d-1 was brought into water column in E zone. In B zone the corresponding numbers was 721.08 mg and 261.26 mg respectively. In A zone the corresponding numbers was 392.10 mg and 123.52 mg respectively.The seston concentration was controlled by sediment resuspension and had positive relationship with TN and TP concentration, which meant that the reduction of sediment resuspension rate resulted in the reduction of seston concentration and consequently reduced the TN and TP concentration in water column. Resuspended particles can either adsorb phosphorus from the water or release it, depending on their P saturation level, so the TDP concentration had negative relationship with the seston concentration.
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