Abstract: Under the background of rapid economic and social development, the disorderly expansion of road landscape has aggravated habitat fragmentation, hindered biological circulation and impaired ecosystem services in coastal beach areas. Simulation of ecological network based on multiple resistance scenarios considering road construction stress is helpful to revealing the impacts of road network on key ecological processes and optimizing regional ecological security pattern. In this study, Dafeng District of Yancheng City was taken as a case study area and analyses were processed based on GIS, Conefor Sensinode, and other software platforms. Three kinds of resistance scenarios were established, which were based on landscape type assignment, modified according to the buffer zone on both sides of the road, and modified according to the high density zone of the road network, respectively. Lastly, ecological networks were simulated and quantitative evaluation on the structure and spatial pattern were conducted. The results showed that the ratio of high density areas of roads was about 8.21%, including central urban area and port area, in which the habitats faced with higher risk of road landscape stress. Under the stress of road network, the area of green land composition of corridors decreased by 7.40%, and the mean curvature increased by 12.82%, which implied that energy consumption of biological migration was significantly increased. The coastal wetland exerted the strongest effects on the other ecological sources in the ecological network, which could provide natural passages for biological migration. Furthermore, it is of great benefit to quantify the impacts of important sensitive factors, e.g. road density, on resistance surface assignment and component structure of ecological network, which can not only help understand the change and underlying mechanism of key ecological processes, but also provide effective support for the construction of regional ecological security pattern.

Key words: Alfalfa, Seed, Seed deterioration, Disease resistance, Field emergence