Change Detection And Analysis Of Surface Coverage On Island And Reefs Via High Resolution Remote Sensing Image

The change detection and analysis for the surface coverage of island and reefs is an important part of surveying and mapping on island and reefs. The census for surface coverage and mapping of the island and reefs can be done by my work, and thus, dynamic monitoring can be realized. By doing this, we can get a good idea of the change of the whole island and reefs, so as to provide a basis for making policies for the development and protection of the island and reefs, therefore, we can exploit the resources more reasonable, meanwhile, the life for people who live there and the ecological environment can also be improved.From the actual needs of surveying and mapping and the dynamic monitoring of surface coverage on island and reefs, this thesis build the technical system of the change detection of surface coverage by using the exist data. There are three aspects which include scope definition, the change detection of surface coverage and the analysis of surface coverage change.To define the boundary of the island and reefs, we extract the coastline to divide the boundary of the sea and the land in order to know our research area. This thesis introduces three methods of extracting the coastline, which includes the automatic extraction by edge detector, the automatic extraction based on DEM and tidal data, the visual interpretation based on stereopair.We select the method of change detection from the needs of different application, which includes two ways: quick change detection and subtle change detection. The method of quick change detection which based on Iteratively Reweighted Multivariate Alteration Detection aims at acquiring a fast estimate and response for the change of surface coverage. The result of extraction only reflects the scope and location of the changed surface coverage in the study area, which doesn't include the detailed change classification. The method of subtle change detection uses the object-oriented classification result. The extraction of change result not only reflects location and area information, but also includes the classification of surface feature in the changed area and the direction of change.The analysis of surface coverage is a statistical study of evolution, it also the fully use of the change results. Based on the result of change detection, the evolution of surface coverage is statistically analyzed by the appropriate model. After comprehending the status of test area in detail, the classified change is analyzed and interpreted reasonably which combining the natural environment in study area.Finally, the applicability of the theory is verified by testing the typical island and reefs. According to the complete technique procedure, the change detection and analysis of surface coverage is tested on Zhaoshu Isle by using high resolution and multi-temporal remote sensing image from multi-sensors.