Abstract:

As an important ecological infrastructure,the green stream corridors play a significant role in improving ecological environment,maintaining biological diversity and enhancing landscape diversity.Taking Chongming Island for example,this paper shows the method of quantitative study for the landscape patterns of the green stream corridors,and also puts forward some corresponding suggestions for the existing problems of the landscape patterns of green stream corridors.Based on landscape ecology theories and landscape pattern indices,using GIS technology to process the basic data of stream corridors,the landscape patterns of each green stream corridor in each administrative district of Chongming Island were analyzed in two aspects,which are the landscape composition of the green stream corridors and the structure of the corridor network.The results indicate that:The total length of the green stream corridor is 952.26 km and the construction ratio of it achieves above 80%.The green stream corridors mostly are narrow and the average width is only〖JP2〗 9.96 m,which causes negative effect on protecting biological diversity〖JP〗.The green stream corridors are scarce in Chongming Island and their overall density is 0.75 km/km2.Among all districts,the green stream corridors in the town have much higher construction ratio and better quality than those in the farms.But the green stream corridors which in the farm areas are much wider than those in the town.The network of the green stream corridors in Chongming Island is very simple while the ratio of line to node and connectivity are small.And the green network is lack of loop which has seriously influence on the development of waterfront ecosystem.

Key words: green stream corridors/Chongming Island/corridor structure/network structure