Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani 12120, Thailand.
Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani 12120, Thailand.
Sci Total Environ. 2017 Dec 1;599-600:689-699. doi: 10.1016/j.scitotenv.2017.05.028. Epub 2017 May 8.
Northeast Thailand makes a significant contribution to fragrant and high-quality rice consumed within Thailand and exported to other countries. The majority of rice is produced in rainfed conditions while irrigation water is supplied to rice growers in the dry season. This paper quantifies the potential impact of climate change on the water footprint of rice production using the DSSAT (CERES-Rice) crop growth model for the Nam Oon Irrigation Project located in Northeast Thailand. Crop phenology data was obtained from field experiments and used to set up and validate the CERES-Rice model. The present and future water footprint of rice, the amount of water evaporated during the growing period, was calculated under current and future climatic condition for the irrigation project area. The outputs of three regional climate models (ACCESS-CSIRO-CCAM, CNRM-CM5-CSIRO-CCAM, and MPI-ESM-LR-CSIRO-CCAM) for scenarios RCP 4.5 and RCP 8.5 were downscaled using quantile mapping method. Simulation results show a considerably high increase in the water footprint of KDML-105 and RD-6 rice varieties ranging from 56.5 to 92.2% and 27.5 to 29.7%. respectively for the future period under RCP 4.5, and 71.4 to 76.5% and 27.9 to 37.6%, respectively under RCP 8.5 relative to the simulated baseline water footprint for the period 1976-2005. Conversely, the ChaiNat-1 variety shows a decrease in projected water footprint of 42.1 to 39.4% under RCP 4.5 and 38.5 to 31.7% under RCP 8.5. The results also indicate a huge increase in the future blue water footprint, which will consequently cause a high increment in the irrigation water requirement in order to meet the plant's evaporation demand. The research outcome highlights the importance of proper adaptation strategies to reduce or maintain acceptable water footprints under future climate conditions.
泰国东北部为泰国国内消费和出口到其他国家的香米和优质大米做出了重要贡献。大部分大米都是在旱作条件下生产的，而灌溉水则在旱季供应给稻农。本文利用 DSSAT（CERES-Rice）作物生长模型，对泰国东北部那翁灌溉项目的水稻生产的水足迹的潜在影响进行了量化。作物物候数据来自田间试验，并用于建立和验证 CERES-Rice 模型。根据当前和未来的气候条件，计算了该灌溉项目区目前和未来的水稻水足迹，即生长期内蒸发的水量。使用分位数映射方法对三个区域气候模型（ACCESS-CSIRO-CCAM、CNRM-CM5-CSIRO-CCAM 和 MPI-ESM-LR-CSIRO-CCAM）的 RCP4.5 和 RCP8.5 情景输出进行了降尺度处理。模拟结果表明，在 RCP4.5 情景下，未来时期 KDML-105 和 RD-6 水稻品种的水足迹分别增加了 56.5%至 92.2%和 27.5%至 29.7%，而在 RCP8.5 情景下，水足迹分别增加了 71.4%至 76.5%和 27.9%至 37.6%。相比之下，ChaiNat-1 品种的水足迹在 RCP4.5 情景下预计减少 42.1%至 39.4%，在 RCP8.5 情景下减少 38.5%至 31.7%。研究结果还表明，未来蓝水足迹将大幅增加，这将导致灌溉用水需求大幅增加，以满足作物蒸发需求。研究结果强调了采取适当适应策略的重要性，以减少或维持未来气候条件下可接受的水足迹。
