| In order to find out the general rule of avian community succession and seasonal dynamics with the development of vegetation succession in Chongming Dongtan Wetland, a whole-year survey was conducted on avian community between October in 2002 and October in 2003. The differences of characteristics of avian community in different seasons and phases of vegetation succession were studied by comparison of their species constitution, abundance, seasonal variation, geographical variation, density, diversity, evenness, dominant species and community similarity. And then the relationship was discussed between environment factors and dynamics of avian community. The results were following:1 . The general rule of vegetation community succession in Chongming Dongtan Wetland. At present, the basic pattern is saline algae community, Scirpus marqueter/Scirpus triqueter community and reed community. If there were no unnatural disturbance, the succession would go on, and terraneous vegetation would take the place of reed community and form climax community.2. The general rules of avian community succession. (1) The avian species abundance is at a low level in the primary stage of vegetation succession, goes up in the second stage, and declines in the high stage. Total of 69 species were observed in saline algae zone, 96 species were recorded in Scirpus marqueter/Scirpus triqueter zone, and 51 species were found in reed zone; (2) The ratio of birds except water bird gradually increase with the development of wetland vegetation succession. It was 7.25% in saline algae zone, 31.25% in Scirpus marqueter/Scirpus triqueter zone and 47.06% in reed zone; (3) The avian density undergoes declination with the development of wetland vegetation succession. The annual average density was 14.63 per hectare in saline algae zone, 7.50 per hectare in Scirpus marqueter/Scirpus triqueter zone and 1 .59 per hectare in reed zone; (4) The avian community similarity in between adjoining stages of vegetation succession was higher than that in between apart stages. The similarity coefficient of avian community was 0.5442 in between reed zone and Scirpus marqueter/Scirpus triqueter zone. The coefficient was 0.6182in between Scirpus marqueter/Scirpus triqueter zone and saline algae zone, and 0.2585 in between reed zone and saline algae zone; (5) The diversity of avian community correlated negatively with the number ratio of dominant species (R=-0.88, PO.01, Y= 3.8956-0.0297X).3. The seasonal difference existed in the construction of wetland avian community of Chongming Dongtan. (1) There were 87 species in autumn, which was at the highest level, 68 species in spring, 47 species in summer and 28 species in winter; (2) The declining trend of avian density was the following: 14.60 per hectare in spring, 9.56 per hectare in winter, 8.28 per hectare in autumn and 2.85 per hectare in summer. The three species with the highest density were Great Knot (4.96 per hectare), Dunlin (4.46 per hectare) and Kentish Plover (1.08 per hectare) in spring, Little Egret (0.35 per hectare), Barn swallow (0.32 per hectare) and White-winged Tern (0.25 per hectare) in summer, Dunlin (1.78 per hectare), Little Egret (1.19 per hectare) and Kentish Plover (1.13 per hectare) in autumn, and Slaty-backed Gull (3.43 per hectare), Herring Gull (1.91 per hectare) and Black-tailed Gull (1.54 per hectare ) in winter.4. Analysis about protected birds in Chongming Dongtan Wetland. (1) The difference of species number of protected birds occurred in different stages of vegetation succession. There were 36 species in reed zone, 64 species in Scirpus marqueter/Scirpus triqueter zone and 57 species in saline algae zone; (2) The difference also existed in varied seasons. There were 56 species in spring, 36 species in summer, 61 species in autumn and 20 species in winter.The discussion was carried on season variation of Little Egret, Dunlin and Common Greenshank. The results showed that there was no significant difference of Little Egret density among seasons (P>0.05), which i...
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