Flash floods occurred frequently in Chinese mountainous areas, that most of the areas had no hydrological station network control. The flood forecasting was crucial for the flash flood disaster warning, prevention and control. In this paper we selected Zhudong River watershed of Pingdu City in China to investigate the application of the HEC-HMS model for flood forecasting in ungauged mountainous area. The design floods of the typical villages in the small watershed were calculated with the HEC-HMS model, and the calculation results were compared with those of the reasoning formula method and the instantaneous unit hydrograph method. The results proved that HEC-HMS model was suitable for the study small watershed and was a powerful tool for flood forecasting in ungauged mountainous area.

The aim of this study was to provide some scientific reference for the protection and restoration of the riverside wetland ecosystem in the cold regions. The study was based on the measurement data of Eddy Covariance observation experiment, to research the variations of water vapor flux over daily and seasonal scales of ecosystem in experimental area, and the factors affecting water vapor flux. This study showed that the diurnal changes of water vapor flux were in a single-peak type, the maximum values appeared between12:00-15:00 hr. On a seasonal scale, the highest value appeared in summer and lowest appeared in winter, and the daily accumulated value of water vapor flux in the growing season was 2.83 times higher than the non-growing season. The water vapor flux was mainly affected by vapor pressure difference, air temperature and radiation, among which radiation had the greatest influence on water vapor flux.