According to the analysis of terrain attributes, using the DSM obtained by drone to conduct a mountainous urban fluvial flood modelling, the resolution of the DSM used should be kept within 1 m to 5 m. However, if larger mountainous cities were involved, in the case of non-extreme discharges, considering the cost of processing, using a resolution of 5 m to 10 m could also meet requirements in terms of inundation area drawing, but there could be a possibility of overestimation of flood depth.

The main objective of this work is to discuss the cumulative effects on flow regime with the construction of cascade reservoirs. A revised IHA (indicators of hydrologic alteration) method was developed by using a projection pursuit method based on the real-coded accelerated genetic algorithm in this study. Through this method, IHA parameters with a high contribution to hydrological-alteration evaluation could be selected out and given high weight to reduce the redundancy among the IHA metrics.

This paper analyzed basic principles and existing flaws of water resources value theories and accounting methods, proposed to primarily account water resources depletion cost, water environment degradation cost and ecological water occupation cost from three aspects, i.e. water resources, water environment and water eco-system. It provides a reference for advancing water resources management, realizing scientific and rational allocation of water resources.

Land use changes alter the hydrological characteristics of the land surface, and have significant impacts on hydrological cycle and water balance, the analysis of complex effects on natural systems has become one of the main concerns. We use different indicators to evaluate changes in land use and establish statistical models for rainfall and runoff. The results show that the predicted runoff is lower than the measured runoff. Eecological protection measures should be strengthened.