SWIM模型在东北黑土区流域的适用性评价——以乌裕尔河中上游流域为例

Assessing SWIM model applicability in the black soil region of Northeast China:A case study in the middle and upper reaches of the Wuyuer River Basin

以典型东北黑土区乌裕尔河中上游流域为研究区,引入SWIM水文模型,利用偏相关系数评价模型参数的敏感性,基于流域出水口依安水文站1961-1997年实测日径流数据和部分气象站小型蒸发皿数据,进行了多站点、多变量的模型率定和验证,并通过模拟结果与实测资料对比,探讨了SWIM模型在东北黑土区流域的适用性、存在的误差及其原因。结果表明:(1)在率定期和验证期,月径流和日径流的纳希效率系数分别大于0.71和0.55,径流相对误差在6.0%以内,月径流的模拟效果好于对日径流的模拟效果;月潜在蒸散发的纳希效率系数达0.81以上;(2)在月尺度上经过校准的SWIM模型可以应用于东北黑土区与径流相关的各种模拟分析;(3)但模型在模拟融雪和冻土产流方面存在一定的限制;对同时具有春汛和夏汛的年份模拟效果也较差;对年降水量出现骤增的年份年径流量的模拟结果会几倍于实测值,但基本能够重现汛期的流量变化过程。模型不仅可以为管理者对该流域水环境综合管理提供水文基础支持,对黑土区其他流域也具有一定的推广和应用价值。

The black soil region of Northeast China is an important national commodity grain base. The Wuyuer River Basin is a typical black soil region and agricultural area in Northeast China. In this paper, a SWIM （Soil and Water Integrated Model） was constructed to study the applicability in the middle and upper reaches of the Wuyuer River Basin. Based on observed daily runoff data from a local hydrologic station and evaporating dish weather data from 1961- 1997, the model was validated using multiple criteria and sites. Special attention was paid to the use of both spatial information （potential evapotranspiration） and more commonly used observations of water discharge at the basin outlet to validate the model. The applicability of the SWIM is evaluated using the Nash-Sutcliffe efficiency coefficient and the relative error of runoff. Based on this analysis, the study discusses the applicability of the SWIM model in the black soil region of Northeast China, and the associated errors and causes. The study reached three key conclusions. First, the Nash-Sutcliffe efficiency coefficients of monthly runoff and daily runoff are greater than 0.71 and 0.55, respectively; the relative error of runoff is less than 6.0%. The simulation efficiency of the SWIM for both monthly runoff and daily runoff satisfies the assessment requirements, but the simulation efficiency of daily runoff is not ideal, and the simulation is more accurate for monthly runoff than daily runoff. The Nash-Sutcliffe efficiency coefficient of monthly evapotranspiration is more than 0.81. Second, the calibrated monthly SWIM model can be used to conduct different runoff simulations and analyses in the black soil region of Northeast China. Third, the study identified structural elements of the model that may limit some uses in the black soil region of Northeast China. The simulated values of spring flood runoff were less than the observed values; and the yearlong simulated results with spring and summer floods were poor. In years with a sudden increase in annual precipitation, the simulated results of the annual runoff were several times of the measured value. However, the model can fundamentally reproduce the flow change process during the flood season. The simulation results have an important reference value to study the impact of land-use change and climate change on hydrological processes at the regional scale. It can provide hydrological information to support the integrated management of the basin water environment, as well as other watersheds in the black soil region.