| The implementation of the "Baosteel Zhanjiang Project" has drastically changed the feature distribution of Zhanjiang East Island in the past ten years, especially the industrial land. This paper based on the Landsat-8 data of 2013, 2017 and 2021, the terrain features of Zhanjiang East Island were classified to study the land use change trend of East Island in the past decade. Taking 2013 data as reference: The NDWI model and the spectral relation model are used to realize the separation of water and land, and the better separation effect is selected by comparison to extract the coastline of East Island; Comparing three supervised classification methods: Maximum Likelihood, Neural Net and Support Vector Machine, and select the one with the best extraction effect to apply to the rest of the data. Construct a verification point set based on the Google earth online map and the measured data of the unmanned aerial vehicle, and use the Confusion Matrix for accuracy evaluation. The results show that: The water-land separation effect of the spectral relation model is better, and the accuracy of extracting island coastlines has been significantly improved; Support Vector Machine has the highest overall accuracy and Kappa coefficient, and the classification results can better reflect the real distribution of ground objects in the study area; Summarizing the classification results of the three years of data, it is found that the growth of land area used for industrial development is prominent and in a continuous growth trend. The spectral relation model and the Support Vector Machine are used to accurately extract the coastline and surface feature types of the East Island respectively, and obtained the land use change trend of the study area in the past ten years, which can provide a reference for the land use planning of the study area. |
