A high-resolution coastal ocean model was developed to simulate the temporal/spatial variability of the Kennebec-Androscoggin (K-A) river plume and the circulation in Casco Bay. The model results agree favorably with the moored and shipboard observations of velocity, temperature, and salinity. The surface salinity gradient was used to distinguish the plume from the ambient coastal water. The calculated plume thickness suggests that the K-A plume is surface trapped. Its horizontal scales correlate well with Q 0.25 , where Q is the volume discharge of the rivers. Directional spreading is affected by the wind with the upwelling favorable wind transporting the plume water offshore. Both the wind and the tide also enhance mixing in the plume. The inclusion of a wetting-and-drying (WAD) scheme appears to enhance the mixing and entrainment processes near the estuary. The plume becomes thicker near the mouth of the estuary, the outflow velocity of the plume is weaker, and the radius of the river plume shrinks. The flow field in the model run with the WAD is noisier, not only in shallow areas of Casco Bay but also in the plume and even on the shelf. We speculate that the WAD processes can affect much larger areas than the intertidal zones, especially via a river plume that feeds into a coastal current.

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The study aims to find a new and effective way to treat petroleum city's contaminated land, and promote the sustainable development of resource-based cities. Qianjiang City combined petroleum-contaminated land remediation with National Mine Park construction, took three modes to treat different degrees of contaminated soils in the Mine Park. Finding out that the petroleum-contaminated treatment site can become Mine Park popular science education base, while Mine Park construction could provide scientific research places and more funds for treatment project. It is conducive to resource-exhausted city to achieve Economic Transition. Combining petroleum-contaminated land treatment and Mine Park construction is a new practical and effective treatment model to restore the ecological environment in petroleum city.

In order to meet the requirements for flood prevention, the blocked river channel of a certain phosphate mine area which located in the Three Gorges Reservoir area requires to be regulated. The river channel has the features of mountain-rivers. The flood prevention standard of the river channel is designed to prevent 50-year flood according to the local meteorological and hydrological data. The gravity gabion retaining walls has been used to support side slopes, the Reynolds gabion cushion has been used to protect the bottom, and the reinforced Mack mattresses has been employed to protect slopes. The results indicate that the minimum cross sectional area of the river is 25.743 m2 under the condition of 50-year flood, which is lower than the designed maximum cross sectional area of the river 31 m2, meaning that the design of the river channel meets the flood prevention requirements. In addition, the special material composition and structure features of gabion structures do not only overcome the defects of the traditional structure which features stereoplasm imperviousness and is prone to aging and failures, but also are characterized by good foundation adaptability and ecological features. This project can be referred to similar projects as the new ideas in river regulation of mine mountain areas.