# Analysis of Coastal Zone Data of Northern Yantai Collected by Remote Sensing from 1990 to 2018
## 1 Introduction  
A coastal zone is an interface between land and ocean. Coastal zones are the most densely populated type of area and are experiencing rapid economic development [1]. The economy of coastal zones plays a very important role in promoting the overall economic development of a country, in China, it is an important part of the national economy [2]. However, with the continuous increase in population, intensification of human activities, and acceleration of urbanization in coastal areas, coastal zones are facing tremendous pressure and disruption such as shortage of marine resources, deterioration of the ecological environment, rising sea level, and pollution, which seriously restrict the sustainable development of the coastal zone economy [3, 4]. Due to its ability to achieve large-scale, fast and real-time dynamic observation, remote sensing technology plays an important role in monitoringthe change process of land cover information in the coastal zone and studying the impact of coastal zone changes on human health, especially in densely populated areas. Therefore, it is of great value to study the changes in the resources and environment along coastlines and coastal zones and their driving factors to understand the changes in the coastal ecological environment and even global changes by means of remote sensing technology [5]. In recent years, the evolution of coastlines and coastal zones has attracted extensive attention from global experts and scholars. Most scholars have focused on monitoring the coastline via remote sensing monitoring and its dynamic changes in areas where human activities are frequent and economic strength is significant [6; 7; 8; 9] or areas where coastal changes are significant [10]. Many scholars have used remote sensing technology to study the characteristics of erosion and accretion changes in natural coastlines [11; 12]. Some scholars have studied remote sensing extraction methods for coastlines [13]. [PERSON] et al. [14] compared and analyzed three methods, iso clustering, threshold, and screen digitization and concluded that iso clustering is the best method of coastline extraction, but traditional methods such as visual interpretation and human-computer interactive visual interpretation are still the more common research methods used by experts and scholars to extract coastal information [15]. For remote sensing monitoring of coastal zones, different scholars have defined the scope of a coastal zone in different ways. [PERSON] et al. [16] analyzed the land use and cover change of coastal zones in different buffer zones around the Bohai Sea, and their results help clarify the current status and changes in the surface coverage of different coastal zones. A coastal zone is representative of a fragile ecological environment, which is vulnerable to human activities. The intensity of human activities is closely related to the diversity of the coastal landscape and the change of the coastline [17]. The health of ecosystems and the marine environment of coastal zone areas are important issues affecting human survival, and studying the change of surface coverage in coastal zones can provide helpful information for solving this problem. Using remote sensing and geographic information system technology to monitor coastline and coastal zone changes has become the topic of much scholarly research in various countries. In many studies, the combination of the two technologies is seldom discussed. One reason for that is due to the difficulty of acquiring data over a long-time span. Other reasons are that many different extraction rules have been used for extracting remote sensing information extraction rules of the coastline and coastal zone, the extraction process is complex, and the relationship between coastline and coastal zone is not always clear. Most scholars only study the coastline or coastal zone and its driving factors.