Effects Of Climate Change On Maize Yield In Northern Liaoning Province And Adaptive Measures

In recent years,the speed of climate change is far beyond our imagination,which has brought a significant impact on China's agricultural production.China has always been a large agricultural country,agriculture is our country to resist the threat of nature and survival.As an important commercial grain production base,the northeast spring corn planting area plays an indispensable role in the national food security strategy.Through field experiments and model simulation,this study used DSSAT-CERES-Maize model to predict the impact of future climate conditions on maize yield in tieling region,and put forward corresponding adaptive strategies,which play an important role in ensuring food security and national stability.This paper took Tieling as an example to represent the northern liao province,and selects Zhengdan958 and Xianyu335 as the representative species in this region,and four cultivation modes(JC?NH?GX?GC)were set up to analyze the changes of agronomic characters and yield of maize under different cultivation modes.The parameter calibration and verification of the DSSAT-CERES-Maize model were carried out,and the future climate data of revised CMIP5 were combined with the model to analyze the changes in future Maize yield and resource utilization rate in tieling region,and to explore adaptive strategies in meteorology,soil and farmland management.The following conclusions were obtained:1.The leaf area index,aboveground biomass and ear weight of maize under GC and GX treatment were higher than that of GC treatment,and the differences in plant height and leaf number were not significant,but the leaf weight was lower.With the exception of 2018,the maize yield of GC treatment was higher than that of GX treatment.Leaf area index,aboveground biomass,ear weight and yield of maize were higher in GX and NH treatments.Compared with JC treatment,leaf area index,abovemeal biomass,leaf weight,panicle weight,plant height and yield were higher under NH treatment.In 2018,compared with 2017 and 2019,the agronomic characters and corn grain yield of Zhengdan958 and Xianyu335 were lower.The main reason is likely to be a severe heat drought in 2018.Compared with JC cultivation model,the corn yield of GC,GX and NH cultivation model increased by 41%,31% and 28%,respectively.It showed that the reasonable collection of techniques such as density regulation,nitrogen stage and tillage measures could promote the growth and yield formation of maize.2.In the context of climate change,precipitation,maximum temperature and minimum temperature during the growth period of spring maize in tieling region all showed an increasing trend,and the corresponding climate trend rates were 12.3mm/10 a,0.35?/10 a and 0.49?/ 10 a,respectively.Solar radiation fluctuated in different years.3.Under the influence of climate change,the future production of Zhengdan 958 and Xianyu335 showed a decreasing trend,and the decreasing range in the middle of the 21 st century was greater than that in the later period.The decrease of Zhengdan 958 yield in the future was less than Xianyu 335,indicating that Zhengdan 958 in tieling area could better adapt to the future climate change compared with Xianyu 335.4.The increase of heat resources in the future had a negative effect on maize production in Tieling area.Climate change was not conducive to the efficient use of water resources in tieling area.In the future climate situation,the nitrogen utilization rate of Zhengdan 958 and Xianyu335 was different.The nitrogen utilization rate of Zhengdan 958 tends to decrease with the change of time,while that of Xianyu335 tends to increase.Therefore,it could be considered to appropriately reduced the nitrogen application amount of Zhengdan 958 and increased the nitrogen application amount of Xianyu335.5.The sensitivity index of rainfall,soil organic carbon content and nitrogen application level to maize yield in tieling area was relatively high.In order to cope with climate change,we could increase the yield of maize by adjusting irrigation,fertilizer supply and straw returning to the field.