The Variation of Land Use Pattern in Tidal Flat Reclamation Zones in Jiangsu Coastal Area: A Case Study of Rudong County of Jiangsu Province

The reclamation and development of tidal flat is the specific land use pattern of coastal area. The variation characteristics of land use in coastal area can provide useful data for land use planning. This paper takes Rudong County as a case to discuss the variation of land use pattern in the tidal flat reclamation zones in Jiangsu coastal area by using the index of land use pattern structure, land use degree and land use diversity. The result shows that the variation of land use types has periodic characteristics from 1949 to 2013. The S-shaped curve and the turning point represent farmland increases in the 30 years after reclamation. The growth of construction land is intermittent with a period of 20 years. The village land use type appears 10 years after reclamation. Highway land and mining land are affected by port development and economic level of reclamation zones. The unused land decreases at first and then keeps staying at a stable level 40 years after reclamation. Land use degree increases in the S- shaped curve and the turning point appears 30 years after reclamation. The change curve of land use diversity shows an inverted U- shaped pattern, and the high point refers to 30 years after reclamation. The land use pattern process is divided into three stages, and the demarcation points are 10 years and 30 years. The formation of land use pattern is because that area of tidal flat increases as a result of marine dynamics. High salinity of soil makes land use pattern simple. Land use pattern is becoming diverse under the pressure of cropland protection, economic benefit, coastal planning, environmental protection and so on. Land use planning should consider to firstly improve soil quality for a 10- year period and planning time should be more than 30 years. Now, it is important for Jiangsu provincial government to pay more attention to the natural status of tidal flat and make great effort to the reclamation and development of tidal flat, in order to improve soil quality and realize sustainable development of tidal flat.