Sogbedji Jean M, McIsaac Gregory F
Dep. of Natural Resources and Environmental Sci., Univ. of Illinois at Urbana-Champaign, W503 Turner Hall, 1102 South Goodwin Ave., Urbana, IL 61801, USA.
J Environ Qual. 2006 Sep 13;35(5):1914-23. doi: 10.2134/jeq2005.0379. Print 2006 Sep-Oct.
Assessing the accuracy of agronomic and water quality simulation models in different soils, land-use systems, and environments provides a basis for using and improving these models. We evaluated the performance of the ADAPT model for simulating riverine nitrate-nitrogen (NO3-N) export from a 1500-km2 watershed in central Illinois, where approximately 85% of the land is used for maize-soybean production and tile drainage is common. Soil chemical properties, crop nitrogen (N) uptake coefficient, dry matter ratio, and a denitrification reduction coefficient were used as calibration parameters to optimize the fit between measured and simulated NO3-N load from the watershed for the 1989 to 1993 period. The applicability of the calibrated parameter values was tested by using these values for simulating the 1994 to 1997 period on the same watershed. Willmott's index of agreement ranged from 0.91 to 0.97 for daily, weekly, monthly, and annual comparisons of riverine nitrate N loads. Simulation accuracy generally decreased as the time interval decreased. Willmott's index for simulated crop yields ranged from 0.91 to 0.99; however, observed crop yields were used as input to the model. The partial N budget results suggested that 52 to 72 kg N ha(-1) yr(-1) accumulated in the soil, but simulated biological N fixation associated with soybeans was considerably greater than literature values for the region. Improvement of the N fixation algorithms and incorporation of mechanisms that describe soybean yield in response to environmental conditions appear to be needed to improve the performance of the model.
评估农艺和水质模拟模型在不同土壤、土地利用系统及环境中的准确性，可为这些模型的应用和改进提供依据。我们评估了ADAPT模型在模拟伊利诺伊州中部一个1500平方公里流域河流硝酸盐氮（NO3-N）输出方面的性能，该流域约85%的土地用于玉米-大豆生产，常见瓦管排水。土壤化学性质、作物氮（N）吸收系数、干物质比和反硝化还原系数被用作校准参数，以优化该流域1989年至1993年期间实测和模拟的NO3-N负荷之间的拟合度。通过使用这些校准参数值来模拟同一流域1994年至1997年期间的情况，测试了校准参数值的适用性。对于河流硝酸盐氮负荷的每日、每周、每月和年度比较，威尔莫特一致性指数在0.91至0.97之间。随着时间间隔减小，模拟准确性总体上降低。模拟作物产量的威尔莫特指数在0.91至0.99之间；然而，实测作物产量被用作模型的输入。部分氮收支结果表明，土壤中每年积累52至72千克氮/公顷，但与大豆相关的模拟生物固氮量远高于该地区的文献值。似乎需要改进固氮算法，并纳入描述大豆产量对环境条件响应的机制，以提高模型性能。
