Discussion on Sampling Methods in Island Vegetation Survey of Species Richness and Biomass

Vegetation is an important part of island ecosystem. Due to the distinction of vegetation from mainland vegetation, the existing mainland sampling method cannot be entirely applied to the islands. Hence it is necessary to combine the existing mainland vegetation sampling methods, and to select different types of islands to test the key links of the methods, and to accumulate data for statistical analysis, so as to obtain the technical methods suitable for island vegetation sampling. Aiming at the application of quadrat method in island vegetation survey, this paper chooses two different survey areas of North Changshan Island as examples, compares different quadrat setting methods, clarifies how to set the quadrat in different kind of slope direction, slope position, and types of plant communities, how much the number of quadrat, and how much the area of quadrat can be set in order to represent the island more completely. Finally, the optimal principle of setting up the island quadrat is determined, which provides scientific basis for the effective selection of the quadrat setting in the investigation of island vegetation community.