以巢湖典型支流丰乐河流域为例，利用分布式水文模型ATHYS对流域降雨—径流过程进行模拟，以期为丰乐河流域水土保持、防洪、水资源利用和非点源污染防治等提供科学依据。ATHYS模型将流域分为大小相同的空间小单元，以库模型进行产流计算，以滞后演算法（lag and route）方法进行汇流计算，并以Nash and Sutcliffe指数作为检验模拟结果的标准，模拟流域出口断面日径流量，初步分析流域径流实测值与模拟值的年际变化。模型模拟结果表明，在率定期和验证期模拟与实测径流量的总Nash and Sutcliffe值（Nash值）都可以达到0.80以上，相关系数均可达0.89以上。除了部分峰值和基流，模型能较好地模拟丰乐河的径流过程。模型模拟径流总量的相对误差在率定期为23.1%，验证期为34.6%。流域降雨量、径流量的年内、年际变化均比较明显，径流实测值和模拟值的年际变化也都比较大。综合来看，模型比较适用于所研究流域的日径流模拟。
used in this model. The model was run in a continuous way at the daily timescale. The discharge at the outlet was available for ten years duration in which five years’s discharge data were randomly selected for the calibration purpose. The comparison observed and simulated discharge was based on Nash and Sutcliffe index. Data from other five years were used for validation. The parameter was calibrated using trial and error method. The model demonstrated a good calibration and validation result with the total Nash coefficients being 0.86 and 0.80, respectively. The maximum Nash coefficient in calibration was 0.92, while the minimum value was 0.68. In validation, the maximum and minimum of Nash coefficient were 0.92 and 0.68. Except for one value, the correlation coefficient between observed and simulated discharge was over 0.9 for both calibration and validation periods. The model can generally well reproduce the hydrograph except for some peaks and some baseflow periods. The relative error of the annul runoff volumes between observed and simulated runoff was about 23.1% in calibration period and 34.6% in validation period. The rainfall and runoff both had a great variation by year, while a corresponding relationship was observed between them. The eigenvalues of rainfall and runoff volume had a great inter-annual variation and the average value of annual rainfall was 1238 m and the variation coefficient was 20.2%. The average value of annual runoff depth was 0.52 and the variation coefficient of annual runoff depth reached to 47.0%. There is no big difference in the average of annual runoff volume and daily peak runoff volume between observation and simulation values, but the observed and simulated runoff volume both showed a great inter-annual variation in total runoff volume and daily peak runoff volume. ATHYS model has proven to be able to simulate runoff from Fengle catchment in a continuous way.