Drought Hazard Assessment In Liaoning Province And Case Study Of Adaptation Measures Under Climate Change Scenario

As the main food crop in Northeast China,the probability and impact of drought damage is becoming more and more significant.Liaoning Province is located on the east coast of Eurasia and the southeastern part of China.The rainfall is unevenly distributed in time and space,and the drought is becoming more and more serious,posing an extremely serious threat to the production of corn.Therefore,it is an urgent problem to clarify the temporal and spatial characteristics of drought risk in Liaoning in the context of future climate change,the impact of climate change on corn production,and the adaption of effective adaptive measures to mitigate the adverse effects of climate change.This paper focuses on the assessment of drought risk in Liaoning Province and a case study of adaptation measures for maize response to drought from vulnerability and yield increase effects.The main conclusions are as follows:1.Can ESM2,CNRM-CM5,MIROC5 and MRI-CGCM3 modes have better weather reproducibility in Liaoning Province.The information diffusion model achieve the risk assessment of drought hazard factors.The results showed that the light drought risk are significantly different between the years,and the risk of light drought between the future period and 1990 s was significant(p<0.05),the increase between 2050 s under the RCP8.5 scenario and 1990 s is the most significant.The medium drought risk in the 2080 s under the RCP8.5 scenario is significantly higher than other periods.The western part of Liaoning Province is a high-risk area with various drought levels.The risk is increasing under RCP4.5 and RCP8.5 climate scenarios in the southern Bohai Bay and other regions.The risk in the north is different under different climate scenarios,the law of change is different and the uncertainty is large.The eastern and central regions are more stable in the ultra-low,low and medium risk levels under various scenarios.2.The drought vulnerability of maize in Tieling area under adaptive measures not only shows significant differences between different ages,but also has different climate scenarios and varieties,and the vulnerability of drought is different.Both 2050 s and 2080 s under RCP4.5 and RCP8.5 showed delayed sowing can significantly reduce the vulnerability.There was no significant difference in the vulnerability between treatments when the irrigation amount was greater than 100 mm.Multivariate analysis of variance showed that the yields of Zhengdan958 and Xianyu335 were significantly different between various sowing dates in the 2020 s,2050s and 2080 s of RCP4.5 and RCP8.5 scenarios,and yields with various sowing date are significant.The variance contribution was higher than the irrigation contribution,and the yield increase was significantly increased with the delay of the sowing date(p<0.05).When the irrigation amount was greater than 100 mm,there was no significant difference in yield between different irrigation levels.3.Under the RCP4.5 and RCP8.5 climate scenarios,the yields of Zhengdan958 and Xianyu335 showed a downward trend(p <0.10)without changing management measures,and appropriate irrigation measures could reduce corn yield reduction to some extent.The best management adaptation measures should avoid the high temperature at the jointing and booting stage,heading and flowering stage and filling and maturity stage,so that the jointing and booting stage and the heading and flowering stage are in the period of sufficient precipitation or irrigation to ensure sufficient water in the sensitive period and reduce the yield loss,reduce drought vulnerability.At 2020 s under RCP4.5 and RCP8.5,Zhengdan958 and Xianyu335 are postponed for 5 days and 10 days respectively.At 2050 s under RCP4.5,Zhengdan958 and Xianyu335 are postponed for 15 and 20 days respectively;both varieties of corn were postponed for 20 days under RCP8.5.At 2080 s under RCP4.5 and RCP8.5,both Zhengdan958 and Xianyu335 are postponed for 20 days.Under different scenarios,in different ages,both varieties of corn need only irrigate 50~100mm water while adjusting the sowing date.