Research And Analysis On Changxing Island Of Dalian Reclamation Change Based On 3S Technology

In the coastal area, the growing economy and increasing population year by year makes the land resources tensions. Reclamation is becoming the effective scheme to solve this problem. With the reclamation gradually expend, makes coastline in the coastal area has a huge impact. The changes of the coastline and the reclamation of the coastal play a vital role in the economic development and the ecological environment. This study selects Dalian Changxing Island as the research object. By using the Landsat remote sensing data, based on 3S technology, research the changes of Dalian Changxing Island reclamation. Frist, using different methods, including threshold segmentation, edge detection and wavelet transformation, extract the coastline of Dalian Changxing Island, to select an optimal method. And then, by using sensing remote data in 7 hours, which are the years of 1980, 1990, 2000, 2005, 2008, 2010 and 2012, extract the reclamation area of Changxing Island, then research and analysis the changes of them. The following is the obtained conclusions:(1) Wavelet transform method displays the natural coastline accurately, and the canny operator in edge extraction method displays the coastline of artificial reclamation area accurately. By using the method which combines the remote sensing image with the Matlab software, makes the extraction of coastline for semi-automated. At the same time, has a fast, efficient, and accurate extraction effect. For the future of Coastline Extraction in Huanghai and Bohai region, this study provides certain reference.(2) The coastline length of Dalian Changxing Island has increased continued in recent 30 years. The key times for the growth are the years of 2005 and 2008: since 2005, the coastline length becomes increase more intense; during the two years from 2008 to 2010, the length and speed of coastline growth are both peaks in recent 30 years.(3) The total area of the reclamation shows a growing trend in recent 30 years, while the annual average reclamation area shows fluctuant trend during this period. The key times for the growth are also the years of 2005 and 2008: before 2005 the overall development of reclamation project shows stable and slowly; after 2005 the reclamation project begin to develop accelerate; since 2008, the reclamation project has entered the peak, shows a rapid development.(4) The economic policy and the reclamation influence each other: on one hand, the decisions of policies and the development of economic play very important roles in promoting the reclamation project; on the other hand, expanding area of reclamation also stimulate the economic development, and then affect policy change.(5) With the continuous change of the coastline length and the reclamation area, the ecological environment of Dalian Changxing Island has been damaged greatly. So that, in the future development of reclamation, when considering the economic benefits brought from the reclamation, it should also research and analysis the damage to the ecological environment.