Variation Characteristics Of Agro-climatic Resources And Their Effects On Climatic Potential Productivity In The Liaohe River Basin

Under the background of global warming,the impact of global climate change on agriculture cannot be ignored.In order to explore the changes of agricultural climate resources and climatic productivity potential in liaohe River Basin,the temporal variation,abrupt and periodic characteristics and spatial distribution of water,heat and light resources in the study area during 1968?2020 were analyzed by using M-K test,Pettitt test,EEMD decomposition method and EOF orthogonal method.Discusses the liaohe river basin spatial and temporal variations of main crops climate productive potential,using correlation analysis and path analysis indicates that the main impact factor of climate productive potential,and through multiple linear regression to explore a certain scenario of main crop production potential climate change trend in the study area,analysis the change trend of main crop yields in the study area and the utilization of agricultural climate resources.The main conclusions are as follows:(1)The annual and growing season precipitation in liaohe River Basin decreased slightly in recent 53 years.The main cycle of annual precipitation was 2.30 a.Precipitation in the growing season took 3.53 a as the main variation cycle.The spatial variation gradually decreased from the southeast coast to the northwest inland.The climate trend rate gradually decreases from southwest to northeast,and the spatial increase and decrease of precipitation are in a bipolar situation.(2)The mean temperature increased at the rate of 0.33 ?/10 a and 0.32 ?/10 a in the interannual and growing season,respectively.The main period of annual mean temperature was 3.79 a.Growth season 3.11 a is the main period of change.The spatial distribution characteristics are roughly consistent with the law of latitude zonal differentiation,and the temperature gradually decreases from south to north.The climatic trend rates of interannual and growing season mean temperature were positive and showed an upward trend,while the increasing extent was affected by latitude and topography.(3)The sunshine duration of both annual and growing season showed a decreasing trend.The main period of interannual sunshine was 2.41 a,and the main period of sunshine in growing season was 2.41 a.The spatial variation trend of sunshine in annual and growing season is basically the same,increasing gradually from southeast to northwest.The spatial distribution of inter-annual sunshine trend rate and growing season sunshine trend rate is roughly consistent.The sunshine duration increases in southwest and southeast of the study area,but decreases in the middle of the study area.(4)The interannual climate productivity potential showed an upward trend,while the change of climate productivity potential showed a downward trend in the growing season.The main cycle of interannual climate productivity potential was 3.31 a,and that of growing season was 3.53 a.The spatial variation trend of annual and growing season is consistent,decreasing gradually from southeast to northwest,and the spatial distribution law of climate trend rate is consistent,and rising obviously in southeast.Zhalute Banner,Tongliao,Kaiyuan,Changtu,Liaoyuan and Chifeng can be used as key development areas.(5)Precipitation is the main limiting factor of climate productivity potential in the study area,and the "warm and wet" climate is conducive to the growth of main crops.Multiple linear regression model shows that the warm and wet climate is more suitable for the growth of main crops in liaohe River basin.Only considering the actual situation of climate resources utilization,the main crops in Liaohe River basin still have the possibility of increasing yield in the future.