| Wetland is not only an important component in city landscape but also a significant part of the ecological infrastructure. Being a core city in the Yellow River delta. Dongying is accelerating its urbanization. At the same time, how to design a wetland landscape properly in cities in the Yellow River delta increasingly aroused the public's awareness, owing to the wetland's role in the city ecological landscape building as well as the seaside saline-alkali soil afforestation.First of all, this essay analyzed the wetland landscape in some main towns near Dongying with the help of the 3S technology which focus on the remote sensing technology.The city wetland landscape can be classified into five types: natural rivers artificial water channels artificial lakes and shallow water mires. According to a survey covering six main towns beside Dongying: Dong cheng Xi cheng He kou Kenli Gudao and Xianhe, the ratios of the wetland area to the total land area vary dramatically . The variation can be explained by the different years at which oil fields had been explored earliest, the ratio is only 5%, which is much lower than that in Gu dao and Xianhe, 22.9% and 27.7% respectively. The oil fields in those two towns had been explored much later than that in Xicheng.In those six towns mentioned above, the artificial water channels and artificial lakes is the biggest part of total wetland area, accounting for 41.4% of the total wetland area. Consequently, the artificial wetland takes a major role in wetland landscape in the towns near Dongying.Generally speaking, the diversity index of the city wetland landscape in the Yellow River delta does not vary substantially. However, the wetland landscape is not continuously .There are small-sized and scattered plates. The continuity index in He Xi cheng and Kenli is far higher than that in Gudao , Dong cheng as well as Xian he .The average density index of riverside galleries in those main towns is 1.49km/km2. The density in Dong cheng and Kenli is higher than in others.What's more, the essay discussed the city wetland landscape designing in the Yellow River delta with theories of landscape ecology and proposed three designing principles ecology principle, art principle and security principle, it also made a statement that in designing the river-bank corridor designers should simulate the natural water channel structure place the bank glacis bended riverways water-storing lakes and riverside plants in proper positions . connect various types of green land with river-bank corridor and finally establish the wetland system.In order to ensure the normal growth of garden plants in the fracture surface of the artificial wetland the gap between the soil surface and the underground water should be kept from 2.1m to 3.9m. It is a good idea to use flexible bank protection and unstructured bank protection in a wetland system.The wetland-centred park is a principal part of city green land in the Yellow River delta. Hence their sizes, amount, shapes and locations should be pondered with landscape ecology theories. The essay made a specific plan for a city wetland system in HeKou for example.The author made a comprehensive survey of the regional plants which is a major component in the wetland system, covering 17 families 28 genera and 34 species .These plants can be classified into 14 different wetland plant communities, such as reed community, cattail-reed community and Suaeda heteroptera community. It also put forward a suggestion of plant communities which fit different levels of saline soil when building an artificial wetland system. Besides, according to the cultivation of 20 perennial hydrophilous species which had been introduced from abroad in various levels of saline soil and water , it is sure that all plants can live through the winter in the open .What's more , seven of them can survive in saline water of 3g/L or saline wetland of 0.3%.
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