Modeling irrigation management for water conservation by DSSAT-maize model in arid northwestern China
Modeling irrigation management for water conservation by DSSAT-maize model in arid northwestern China
复制标题
利用 DSSAT-玉米模型对中国西北干旱地区的节水灌溉管理进行建模
DOI：
10.1016/j.agwat.2016.06.014
复制
发表时间：
2016-11
影响因子：
6.7
通讯作者：
Bai Xiao
中科院分区：
文献类型：
--
作者：
Jiang Yiwen;Zhang Lanhui;Zhang Baoqing;He Chansheng;Jin Xin;Bai Xiao
有效的灌溉和用水对该区域的可持续发展和水资源管理十分重要。本文以西北黑河流域中游绿洲盈科灌区为研究区，应用DSSAT-maize v4.5，探讨不同气候条件下的最佳灌溉策略，在保持产量的同时提高有益耗水量，减少非有益耗水量。首先基于作物产量、物候期和土壤含水量数据对模型进行了校准，在校准和验证期间，模拟数据与观测数据都达到了很好的一致性。在定标期内，模拟玉米物候期与观测期相差2天，籽粒产量的标准化均方根误差（nRMSE）为6%。在验证期内，2006年和2008年产量的RMSE值分别为4.95%和2.96%，土壤含水量的RMSE值为0.118 ~ 0.046。利用校正后的模型模拟了不同灌水处理对玉米产量的影响，计算了不同灌水处理对玉米产量的潜在减少水量。结果表明：盈科灌区4月上旬至4月中旬为最佳种植期，拔节期和抽穗期为最佳灌溉期；不同气候条件下的最佳灌水量不同，湿润年、正常年和干旱年的最佳灌水量分别为1000 m3/ha左右、4200 m3/ha左右和4800 m3/ha左右。在模拟灌溉方案下，该区的灌溉水量可减少近一半。一旦经过实地试验验证，模拟灌溉情景将为研究区有效的水资源管理提供部分依据。
Water shortage is a chronic problem in arid Northwest China, where agriculture cannot exist without irrigation. Efficient irrigation and water uses are important to sustainable development and management of water resources in the region. This paper applied DSSAT-maize v4.5 to the Yingke Irrigation District in the middle reach oasis of the Heihe River Watershed in Northwest China to explore the optimal irrigation strategies under different climatic conditions, and to improve the beneficial water consumption and reduce non-beneficial water consumption while maintaining yields at the same time. The model was first calibrated based on the crop yield, phenological phases and soil water content data, and good agreements were achieved between the simulated and observed data in both the calibration and validation periods. In the calibration period, the simulated maize phenological phases differed by two days of the observed phases, and nRMSE (normalized root mean square errors) for grain yield was 6%. In the validation period, the values of nRMSE of yield were 4.95% in 2006 and 2.96% in 2008, respectively, while the RMSE for soil water content ranged from 0.118 to 0.046. Subsequently the calibrated model was used to simulate the effects of planting dates and different irrigation treatments on maize yield and the potentially reduced water amount was calculated. Results show that in the Yingke Irrigation District, the best planting dates range from early April to mid-April, and the best irrigation periods are the jointing and tassel phases. The optimal irrigation amounts vary under different climatic conditions, ranging from about 1000 m3/ha, to 4200 m3/ha, and to 4800 m3/ha in wet, normal and dry years respectively. Nearly half of the irrigation amount could be reduced under the simulated irrigation schedule for the district. Once validated by field tests, the simulated irrigation scenarios would provide partial basis for effective water resources management in the study area.