Water Engineering and Management, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani 12120, Thailand.
Water Engineering and Management, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani 12120, Thailand.
Sci Total Environ. 2019 Feb 20;652:189-201. doi: 10.1016/j.scitotenv.2018.10.201. Epub 2018 Oct 16.
This study investigates rice yield and evaluates potential adaptation measures on field management practices for rainfed rice production under climate change scenarios in the Songkhram River Basin, Thailand. The top-down and bottom-up approaches are combined to evaluate the future climate conditions in the Songkhram River Basin and identify adaptation strategies respectively. An ensemble of four Regional Climate Models (RCMs) bias-corrected using the Quantile Mapping technique was used to project the future climate under two climate change scenarios (RCP4.5 and RCP8.5). The DSSAT crop simulation model was used to simulate rice yield and evaluate the impacts of climate change on rice yield, as well as the feasibility of four adaptation options, which were solicited from four hundred farmers through questionnaire surveys in the basin. The strategies include (i) change in planting date, (ii) change in fertiliser application date, (iii) change in fertiliser application dose, and (iv) supplying irrigation water. Based on the model results, future maximum and minimum temperatures are expected to increase by 2.8 and 3.2 °C respectively under RCP8.5 scenario for 2080s. Although annual rainfall may be unchanged, rainfall patterns will shift earlier in future. Evaluation of adaptation strategies suggest that supplying irrigation water under RCP4.5 and RCP8.5 scenarios respectively are the best strategies to increase rice yield under climate change scenarios. Change in fertiliser application date and change in planting date can increase the future rice yield by 12 and 8%, respectively under RCP4.5 scenario for 2080s. Adjusting the fertiliser application dose may however reduce future rice yield. Although supplying irrigation water can aid the production of rainfed rice, other concerns such as the source of water are involved. The feasibility of adaptation actions would depend largely on available resources and mindset of farmers. Further work is warranted in exploring a combination of adaptation strategies and management plans to combat the adverse impacts of climate change.
本研究调查了水稻产量，并评估了泰国宋卡河流域在气候变化情景下针对雨养水稻生产的田间管理实践的潜在适应措施。采用自上而下和自下而上的方法分别评估宋卡河流域未来的气候条件并确定适应策略。使用经过定量映射技术校正的四个区域气候模型（RCM）的集合来预测两种气候变化情景（RCP4.5 和 RCP8.5）下的未来气候。使用 DSSAT 作物模拟模型来模拟水稻产量，并评估气候变化对水稻产量的影响，以及四个适应选项的可行性，这些选项是通过在流域内进行的四百名农民的问卷调查征集而来的。这些策略包括：（i）改变种植日期，（ii）改变施肥日期，（iii）改变施肥量，和（iv）提供灌溉水。根据模型结果，预计在 RCP8.5 情景下，2080 年代未来的最高和最低温度将分别升高 2.8 和 3.2°C。尽管年降雨量可能保持不变，但未来的降雨模式将提前转变。对适应策略的评估表明，在 RCP4.5 和 RCP8.5 情景下分别提供灌溉水是在气候变化情景下提高水稻产量的最佳策略。在 RCP4.5 情景下，改变施肥日期和改变种植日期可分别将未来的水稻产量提高 12%和 8%。然而，调整施肥量可能会降低未来的水稻产量。虽然提供灌溉水可以帮助生产雨养水稻，但还涉及到其他问题，如水源。适应措施的可行性在很大程度上取决于可用资源和农民的思维模式。需要进一步研究探索适应策略和管理计划的组合，以应对气候变化的不利影响。
