Abstract:Three sites were selected for samples in Lake Taihu to observe temporal and spatial distribution of redoxpotential(Eh),pH, total nitrogen (TN),total phosphorus (TP) and organic matter(OM) in sediments. Belowthe surface of sediments Eh declined rapidly with the increase of sediment depth and it was under anaerobic condi-lion except the top layer of sediment. pH value changed silightly in the profile of sediments, which ranged from 6. 4to 7. 8. With a comparison between four seasons, p.H value was the lowest in winter. TN and TP concentrations insediments of Lake Taihu were higher, and the maximum concentrations reached 2. 68 mg/g and 0. 864 mg/g. respectively. Their vertical profiles showed that TN snd TP concentrations in surface sediments were much higherthan in deeper layers and decreased steeply with the increase of the depth on the top 15 cm of sediment layers. OMconcentrations declined rapidly al the top 15 cm of sediment layers, but there was little change in four seasons. Thesediment loads of TN and TP were much higher at Sl than that at other sites.