Transitions Of Seacoast In Chaochow Gulf From Song Dynasty

This paper applies historic geography and brine dynamics rehabilitating the seacoastal transitions of Chaochow Gulf from the song dynasty. Study showed that the three seacoasts of Chaochow Gulf took on different transitional states in historical phase due to different natural circumstances. Prior to Tongzhi Emperor time, Qing Dynasty, the developments of the three seacoasts were tardy while after that, ooze silted up at a faster speed. And potatoes, which were widely planted in this area, accounted for the speeded seacoast transitions.The natural attributes strengthened man's ability to exploit uplands and hilly regions. And then, large-scale exploitation of uplands and hilly regions aggravated soil erosion, thus the silted seacoasts. Different distribution landscapes in counties had different influences on the seacoastal transitions of Chaochow Gulf. Potatoes planted in Zhanyuan County, upstream of the Dugu River, and Ye County, upstream of the Xiaogu River, worked upon slightly on the seacoastal transitions of Chaochow Gulf for their small plantation scope and low production,While Gaomi, located in the plain, was of developed economic crops, and potatoes , though, was planted in a small scale, but the output per acreage was high. The scattered distributions wouldn't affect the seacoastal transitions too much. The uplands and hilly regions of Laiyang County and Pingdu County were located in middle-stream of Gu River basin, and moderate temperature, moisture and soil there made potatoes planted widely, representing a landscape of large-scale potato planting in these regions. Thus soil erosion has been aggregated for the large-scale planting of potatoes. A great amount of silt poured into Chaochow Gulf, along with Dugu River and Xiaogu River, and speeded up the seacoastal transitions. This was the main reason for the obvious development of north seacoast in Chaochow Gulf after Tongzhi Emperor time, Qing Dynasty.In Jiaozhou County, potatoes were planted highly concentrated in South and scattered in North. Northern regions, which were low hilly ones, were the river basin. When potato were introduced, low hilly regions in the south of Jimo County have been cultivated greatly. With Baisha River, Li village River and Moshui River, silt caused by potato planting infused into Chaochow Gulf and promoted the developments of the seacoasts distinctly. These rivers were short and drainage areas were not so wide, therefore the developments of southern seacoasts in Chaochow Gulf were not as severe as those in the northwest, despite the clear developments. Different distributions of potatoes in counties reflect the natural diversities of different places.