| River management has always been an important role along with the developing society. In different periods, the functions of river are various and according to the different objectives, there are many ways of river management. In the20th century, unreasonable river management in urban has resulted in huge losses and catastrophe, so it has been becoming an awareness that the ecological management in urban rivers has much to do with the city’s sustainable development. In the late1990s, owing to the attempts of environment-friendly river management in some cities of our country, ecological river management has been developed fast and acquired many effects. While because of the changing of landscape configuration and construction materials, the riverbed resistances changed from channelized to ecological watercourse and these would affect flood carrying capacity absolutely. Meanwhile, as a result of the increasing number of bridges over the river in urban, the backwater effect caused by bridges would also effect flood prevention. According to the above, it is necessary to research the consequences of ecological river managements and the backwater effects caused by bridges. Take the urban district of Haicheng River as an example, a flood numerical model was employed to research the flood carrying capacity before and after the ecological management in this paper.Contents of the paper are as follows:(1) Choosing the Dongsandao to Express Railway Bridge from Haicheng River, MIKE11was used to simulate flooding course. The flood event of the year2002was simulated and the resistances obtained by satellite were used to calibrate the model. Results of the model were good enough to apply to assessment of flood control capacity of the embankments. A fifty year return period numerical model for flooding was established, and from which flood surface level was obtained and the flood control capacity was analyzed.(2) Construction of Multispectral Image Database. To remote It is the most common method for terrain classification. With the development of remote sensing, the number of object spectrum data increases continuously. In order to preserve, manage and depart the information efficiently, construction of spectrum database seems to be a very important job. The spectra of terrain features in Haicheng River basin were measured in the paper, and it would be vital information when it comes to construction of local hyperspectral database.(3) In light of the changing watercourse in urban district, the effect of riverbed resistance from channelized to ecological watercourse on flood carrying capacity was analyzed. In addition, to research the backwater effect caused by bridges, a model was established and the modeling result was compared with that of the criterion formula.(4) Haicheng River plays an important role in Haicheng City. Considering the current terrain feature and the continuity of the water bank ecosystem, natural and artificial-natural bank protection was applied in the paper to research environmental planning of Haicheng River in urban district. The above work enables Haicheng River to improve self-purification capacity and protect biodiversity, as well as to ensure the health of the river’s ecosystem.In the end, the paper summarizes the research work and makes a prospective for the next step. |
