Temporal-Spatial Distribution Characteristics of Different Rainfall Levels in the Mihe River Basin from 1976 to 2020
To study the rainfall characteristics and future trend in the Mihe River Basin,based on daily rainfall data of 15 stations in the basin from 1976 to 2020,Mann-Kendall non-parametric test,inverse distance interpolation and rescaled range(R/S)analysis were used to analyze the characteristics of temporal-spatial variation for rainfall and rainfall days at different rainfall levels.The impacts of the different rainfall levels variation on the annual rainfall were explored and the future trend of rainfall structure was discussed.The results show that during the research period,the annual rainfall shows an increasing trend,except for heavy rainfall,other rainfall levels also show an upward trend.The rainfall days generally decrease,and only the moderate rainfall days and rainstorm days show an upward trend.Spatial distribution characteris-tics of the annual rainfall shows a decreasing trend from the upstream to the downstream of the basin,which is consistent with the spatial variation of heavy and rainstorm rainfall.The spatial distribution characteristics of the annual rainfall days and light rainfall days show a similar pattern.The highest contribution rate of moderate rainfall to annual rainfall is 27.99% ,and the highest incidence rate of light rainfall is 72.07% .According to the correlation analysis,the changes of the annual rainfall and the rainfall days in the basin are most affected by the rainstorm and light rainfall days,respectively.The indicators related to rainstorm,rainstorm days and annual rainfall show strong persistence,the future trend is consist-ent with that of the past,indicating that the rainfall levels have a trend of transferring to rainstorm.
rainfallrainfall leveltemporal-spatial distributionthe Mihe River Basin
NETL
NSTL
万方数据
