Impacts of day versus night temperatures on spring wheat yields: A comparison of empirical and CERES model predictions in three locations
Impacts of day versus night temperatures on spring wheat yields: A comparison of empirical and CERES model predictions in three locations
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DOI：
10.2134/agronj2006.0209
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发表时间：
2007-03-01
期刊：
影响因子：
2.1
通讯作者：
Ortiz-Monasterio, J. Ivan
中科院分区：
文献类型：
--
作者：
Lobell, David B.;Ortiz-Monasterio, J. Ivan
最近的温度观测趋势和未来的模式预测的特点是日最低温度（tmin）相对于日最高温度（tmax）变暖更大。为了帮助了解最小和最大的差异如何影响作物产量，我们分析了区域春小麦产量和温度的变化，在北美西部的三个灌溉点，其特点是最小和最大之间的低相关性。作物模型CERES-小麦v3.5在每个地点进行了评估，并用于预测未来对温度变化的反应。Train和tmax与产量表现出明显的历史相关性，CERES成功地捕捉到了每个地区的观察关系。在墨西哥的亚基河谷，历史产量与tmin密切相关，但与tmax无关。然而，CERES预测的响应增加的最小温度或最大温度（保持其他变量不变）是相似的（类似于6%摄氏度-1），表明最小温度的明显的历史重要性，主要是由于温度和太阳辐射之间的协变，而不是更大的直接影响，最小温度对产量。在墨西哥的圣路易斯-墨西卡利山谷和加州的帝王谷，观察到了相反的情况：历史产量与tmin和tmax的相关性是相似的，但对tmax的预测响应大约是火车的三倍。后者的解释是相反的影响，在CERES的籽粒灌浆速率的最小值和最大值，较高的最小值增加收获指数。这一模型机制没有得到历史数据的明确支持，在预测产量对气候变化的反应方面仍然存在不确定性。
Trends in recent temperature observations and model projections of the future are characterized by greater warming of daily minimum (tmin) relative to maximum (tmax) temperatures. To aid understanding of how tmin and tmax differentially affect crop yields, we analyzed variations of regional spring wheat yields and temperatures for three irrigated sites in western North America that were characterized by low correlations between tmin and tmax. The crop model CERES-Wheat v3.5 was evaluated in each site and used to project future response to temperature changes. Train and tmax exhibited distinct historical correlations with yields, with CERES successfully capturing the observed relationships in each region. In the Yaqui Valley of Mexico, historical yields were strongly correlated with tmin but not tmax. However, CERES projections of response to increased tmin or tmax (holding other variables constant) were similar (similar to 6% degrees C-1), indicating that the apparent historical importance of tmin mainly results from covariation between temperatures and solar radiation and not greater direct effects of tmin on yields. In the San Luis-Mexicali Valley of Mexico and in the Imperial Valley of California, the opposite was observed: historical yield correlations with tmin and tmax were similar, but projected responses to tmax were roughly three times larger than train. The latter is explained by opposing effects of tmin and tmax on grain filling rates in CERES, with higher tmin increasing harvest indices. This model mechanism was not clearly supported by historical data and remains an area of uncertainty for projecting yield responses to climate change.