晋江流域HEC-HMS模型关键参数的分区率定

为进一步揭示流域自然地理条件的空间分异，以及大型水库等人类活动对分布式水文模型参数时空变化的影响，以东南沿海的晋江流域为典型区，通过对研究区内3个水文站和山美水库集水区的亚区设置，构建晋江流域HEC-HMS模型；选取1996－2014年历年最大一场洪水系列，运用循环渐近法，对模型进行分区率定，以分析模型关键参数初损率λ和波速V的时空变化。结果表明：（1）分区率定法可以得到流域不同区域模型关键参数的合理取值。（2）模型关键参数时空变化明显，其中，初损率λ在4个亚区的平均值分别为0.33、0.54、0.559和0.571，与区域的土地利用结构、水利工程等因素有关，水库集水区的初损率平均值最小，可能与区域林地面积增加以及水库蓄水有关；初损率在时间上的变化则与相应时间的起涨流量相关，起涨流量越大则初损率越小。5个不同区域河道的波速V平均值为3.218、2.241、1.95、1.427和1.217 m/s，呈上游至下游递减，区域平均坡度越大则波速越大；而波速V在时间上的变化与最大6 h降雨量及上游来水条件相关，降雨量越大、上游水量越大则波速越大。（3）分区率定方法充分利用了流域水文控制站点的水文资料，构建的流域HEC-HMS模型，可以更好地反映流域不同区间水文过程的变化 A case study was conducted in the Jinjiang River basin,which is located in south east coast of China,in order to explore how the spatial variations of the natural conditions and the human activities like large reservoir affect the temporalspatial variations of the distributed hydrological model parameters.Three hydrological stations and the dam of Shanmei Reservoir were used to separate the watershed into four subareas and the method of multi sites calibration and validation was used to set up the HEC-HMS model.The annual largest flood series from 1996 to 2014 were selected and two key parameters,the initial loss rate (λ) and the flood wave velocity (V),were calibrated in each sub area with approximate circulation method.The results showed that:(1) The multisites calibration method was effective to obtain the values of key parameters in each subarea.(2) The temporal spatial variation of parameters was clear.The annual average of the initial loss rates at four sub area were 0.33,0.54,0.559 and 0.571,respectively,being affected by the land use and water conservancy project.The initial loss rate at reservoir catchment area was the lowest one among the four sub areas,which indicated that woodland increasing and reservoir storage decreased the initial loss rate.The temporal variation of initial loss rate was dependent on the initial discharge.The greater the initial discharge was,the smaller the initial loss rate was.The annual averages of flood wave velocity at different sub area were 3.218,2.241,1.95,1.427 and 1.217 m/s,respectively,and it decreased from upstream to downstream.The spatial variation of flood wave velocity was related to the average slope of the watershed while the temporal variation was related to the largest 6 h areal rainfall and upstream runoff.A larger of the average slope and areal rainfall leads into a greater of wave velocity.(3) The method of multi sites calibration for setting up of HEC-HMS made it possible to reveal the differences of hydrologic processes in different region of the basin.