Abstract: It is of great practical significance to study the impact of construction land expansion on the habitat network from the perspective of ecosystem service function. We focused on Su-Xi-Chang area of the rapid urbanization area as a case study, with the little egret (Egretta garzetta) as a representative species and from the perspective of ecosystem service function. We discussed the relationship between the construction land expansion, habitat network and ecosystem service function by way of the land change class analysis method and the monetary of ecosystem service function. The results showed that: 1) Construction land expansion on total ecosystem service function of habitat network have higher influences comparison of construction land expansion on regional ecosystem service function value that led directly to land changes; 2) As far as habitat network land, construction land expansion led to total ecosystem service function value of migration corridor and habitat patches reduced, and the construction land expansion had further critical effect on migration corridor’s ecosystem service function value than habitat patches.Besides, migration corridor’s ecosystem services more diversified than habitat; 3)The construction land expansion led directly to decrease of the ecosystem service value based on the survival needs of the egret habitat, and the rate of change is greater than the total value of ecosystem services; The construction land expansion led to lack of ecological processes in habitat land,such as species migration and gene flow, affecting the network function indirectly. The study can provide reference for the direction and intensity of Su Xichang's construction land expansion, and it is an important guarantee for regional biodiversity diversity and ecosystem health.
Key words：construction land expansion; ecosystem service function; habitat networks; rapidly urbanizing area