# Analysis of Coastal Zone Data of Northern Yantai Collected by Remote Sensing from 1990 to 2018
## 3 Results
### Relationship between coastline change and coastal surface cover change  
The change of land cover types in offshore areas will have a certain impact on the change of coastline types and lengths. Through comparative analysis, it was found that the changes of coastal structures, manually excavated land, and roads in the study area are related to the length of the artificial coastline. From 1990 to 2018, the length of the coastline in the study area increased with the use of  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  & & & \multicolumn{6}{c}{**Areas Increased or Decreased in 1990-2018 (km\({}^{2}\))**} \\ \cline{2-10}
**City** & **Roads** & **Building Areas** & **Desert/Bare Land** & **Forest/Greesses** & **Cultivated Land** & **Structures** & **Manually** & **Exevated Land** & **Waters** \\ \hline Laizhou & 2.38 & \(-\)0.57 & \(-\)4.78 & 37.71 & \(-\)22.63 & 50.65 & 2.02 & \(-\)19.18 \\ Zhaoyuan & 0.84 & \(-\)1.42 & \(-\)3.01 & 1.28 & 1.36 & 1.33 & 0.33 & 0.00 \\ Longkou & 11.08 &  
structures, manually excavated land and roads as the coastline, and the length of the artificial boundary line in the study area also increased. The correlation is shown in Figure 10.  
Human activities have brought about significant changes in resources and to the environment of the coastal zone, which have not only shaped many types of artificial coastline landforms, such as harbor and wharf, protection engineering, and coastal construction, but they also have had a great impact on the natural evolution process of the coastal zone. The coastline of Yantai is clearly affected by the change of land use in the coastal zone, especially by structures, manually excavated land, and roads. Through comparative analysis of the impact of structures, manually excavated land, roads, and desert/bare land on the coastline from 1990 to 2018, we determined that the artificial boundary line in the northern coastal area of Yantai is directly proportional to the length of the coastline with roads as the coastline, which was the most significant correlation (R\({}^{2}\) = 0.9527, \(P<0.01\)). It can be seen that in the past 30 years, roads have had the greatest impact on the coastline changes in the northern coastal areas of Yantai, and the impact of structures and manually excavated land on the coastline changes is more significant, which is the impact of frequent human activities on the coastline.  
Yantai has a superior geographical location and abundant marine resources, and its coastal zone has a long history of development. In recent years, the coastal regional economy of northern Yantai has developed rapidly. The port cities headed by Zhifu, Penglai, and Laizhou have been growing steadily. The construction of the Longkou artificial island group has increased the driving force for the overall economic development of Yantai [18]. However, at the same time, people need to be aware of the series of health problems brought about by the overdevelopment of coastal areas. How to minimize the damage while undergoing developing has become an urgent problem that needs to be solved.