# Analysis of Coastal Zone Data of Northern Yantai Collected by Remote Sensing from 1990 to 2018
## 3 Results
### Analysis of Surface Cover Change in the Coastal Zone  
In 2018, the coastal land cover in the northern Yantai coastal area was dominated by forests/grasses cover and structures, accounting for 31.40% and 15.45% of the study area, respectively, while other land types accounted for a relatively small proportion. From 1990 to 2018, the area of forests/grasses covers, and structures increased, while the area of desert/bare land and water area decreased. Among them, forests/grasses cover area increased from 153.56 km\({}^{2}\) to 249.65 km\({}^{2}\), structure area increased from 9.88 km\({}^{2}\) to 122.84 km\({}^{2}\), desert/bare land area decreased from 129.46 km\({}^{2}\) to 37.20 km\({}^{2}\), and water area decreased from 93.15 km\({}^{2}\) to 80.83 km\({}^{2}\) (Figure 9)  
Figure 8: Fractal dimension change of coastline in the research area from 1990 to 2018.  
Figure 9: Surface cover map of coastal zone from 1990 to 2018.  
[PERSON]'s research reported that the coastal land area of Shandong Province is continuously increasing [34]. The eight counties and municipalities involved in the northern coastal area of Yantai studied in this study are all located in the northern part of Shandong Province, and the coastal land area has been increasing over the past 30 years. From 1990 to 2018, the coastal areas of Longkou and Laishan increased by 52.54% and 34.63%, while those of Fushan and Mouping increased by 8.05% and 9.04%. Table 6 shows the change of surface coverage of the first-class coastal zones in each county and municipality from 1990 to 2018. The study found that from 1990 to 2018, the area of structures in the study area increased the most, to 112.96 km\({}^{2}\), of which the area of structures in Laizhou increased by 50.65 km\({}^{2}\), accounting for 44.84%. The area of desert/bare land decreased the most, by 92.26 km\({}^{2}\), and Penglai City decreased the most, by 48.46 km\({}^{2}\), accounting for 52.53%. In contrast, the changes in building areas and water areas are relatively small, i.e., 5.87 km\({}^{2}\) and 12.32 km\({}^{2}\), respectively.  
Based on the vector data of the coastal zone extracted by remote sensing, the transfer matrix analysis of various types of coastal zone areas in the study area from 2015 to 2018 was carried out to fully understand the land pattern transformation of the coastal zone in the study area in recent years. As can be seen from Table 7, from 1990 to 2018, forests/grasses cover and structure transfer area were the largest, 139.92 km\({}^{2}\) and 70.58 km\({}^{2}\), respectively. The increased area of forests/grasses cover was mainly transformed from cultivated land and desert/bare land. The increased area of structure was mainly transformed from water area, desert/bare land, and building area. Desert/bare land has the largest area of transfer, of which 35.72 km\({}^{2}\) is converted into forests/grasses cover, and then into cultivated land, building areas, and structures. In addition, the change of manually excavated land is not clear, and the increase only accounts for 2.70% of the total change. Generally speaking, the region presents a state of transition from desert/bare land, cultivated land, and building areas to forests/grasses cover and structures, but the overall area of the study area experienced little change and is relatively stable.