Due to anthropogenic climate change, cover crop water consumption in winter could potentially increase drought stress for a succeeding crop. Simulation of cover crop evapotranspiration (ET) losses could be a tool for farmers to make smart management decisions. In Germany, the model AMBAV is used by the German Meteorological Service (DWD) to advise farmers in irrigation management. We compared measured ET of phacelia (Phacelia tanacetifolia), oilseed radish (Raphanus sativus var. oleiformis) and white mustard (Sinapis alba) cultivated in a container experiment with simulated data and conducted a sensitivity analysis to identify the meteorological and crop-specific parameters, which had the strongest effect on simulated ET. In general, measured ET exceeded simulated ET. Different statistical criteria showed that AMBAV performed best for the simulation of evaporation from a bare soil surface. Model performance was also strongly influenced by the irrigation regime in the container experiment. However, the sensitivity analysis showed that changes in irrigation hardly influenced simulated ET. We recommend optimization of the model for irrigated agriculture. Furthermore, we identified temperature and humidity as the most important meteorological and leaf area index as the most important crop-specific parameter for ET simulations with AMBAV. Since farmers' management decisions depend on the accuracy of ET simulations, they should be aware that even small regional deviations of meteorological conditions and soil cover can significantly affect model predictions.

中文翻译：

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覆盖作物耗水量：在容器实验中分析用于计算实际蒸散量 (AMBAV) 的农业气象模型的性能

由于人为气候变化，冬季覆盖作物的耗水量可能会增加后续作物的干旱压力。覆盖作物蒸散（ET）损失的模拟可以成为农民做出明智管理决策的工具。在德国，德国气象局 (DWD) 使用 AMBAV 模型为农民提供灌溉管理方面的建议。我们比较了雉鸡 ( Phacelia tanacetifolia )、油籽萝卜 ( Raphanus sativus var. oleiformis ) 和白芥菜 ( Sinapis alba)的 ET 测量值）在容器实验中用模拟数据进行培养，并进行敏感性分析，以确定对模拟蒸散影响最强的气象和作物特定参数。一般来说，测量的蒸散量超过模拟的蒸散量。不同的统计标准表明，AMBAV 在模拟裸露土壤表面的蒸发方面表现最佳。模型性能也受到容器实验中灌溉方式的强烈影响。然而，敏感性分析表明灌溉的变化几乎不影响模拟蒸散。我们建议优化灌溉农业模型。此外，我们将温度和湿度确定为最重要的气象参数，将叶面积指数确定为 AMBAV 蒸散模拟中最重要的作物特定参数。