Spatio-temporal Change Characteristics Of Climatic Suitability Degree Of Maize In Western Liaoning Province In Recent 60 Years

Agricultural climate resources refers to climate of one region which can provide natural climatic conditions and potential of biomass energy for agricultural production and its implications for the development of agricultural production.They not only involved in the process of agricultural production directly but also can be used for agricultural production.Global climate change has become the indisputable facts and brought survival challenge of human environmental and socio-economic development.Agriculture is one of the most sensitive industries in response to climate change,the change of agricultural climate resource has brought certain effects on crop growth,even threaten sustainable development of regional agriculture.Therefore analysis the Spatio-temporal characteristics of suitability degree for regional crop in favour of agricultural production to adapt to climate change and layout reasonably.It also lay the scientific foundation for achieve sustainable development of agricultural production.Western Liaoning is the main producing area of maize in Liaoning province,ensure the region’s corn production safety in the context of climate change have great practical significance.Basis on a climatic suitability degree model for optimal maize production,daily meteorological data for 1956-2014 from eight meteorological stations in four cities in West Liaoning Province were analyzed.The analysis included the spatial and temporal distribution characteristics of temperature,precipitation,sunshine and integrated climate suitability degree during the whole growth period and each individual growth stage of maize using climate trend rate,spatial interpolation（IDW）,Empirical Orthogonal Function（EOF）analysis and wavelet transformation analysis.The results showed that:（1）Nearly 60 years,the suitability degree of integrated climate during the whole growth period of maize in Western Liaoning area mean to 0.605,it show that agricultural climate resources are suitable,and meet the physiological needs of maize basically;the suitability degrees of precipitation,sunshine and integrated climate followed a declining trend during the whole maize growth period(respectively:-0.003?10a^-1、-0.004?10a^-1、-0.002?10a^-1).The suitability degree of integrated climate dropped at sowing,emergence and maturity stages but rose at flowing stage(respectively:-0.006?10a^-1、-0.005?10a^-1、-0.004?10a^-1、0.016?10a^-1).（2）On the spatial distribution,the suitability degrees of both temperature and sunshine during the whole growth period of maize and the suitability degree of integrated climate during sowing and maturity stages tracked an increasing trend from south to north,from west to east,from west to southeast and northeast,and from northeast to southwest in West Liaoning Province.However,the suitability degrees of temperature and sunshine at emergence stage were in contrast to that of sowing,with a general declining trend from northwest to southeast and northeast.The suitability degrees of precipitation,integrated climate during the whole growth period of maize and integrated climate dur ing flowering followed a‘low-high-low-high’zonal distribution from north to south.The constraint factors during sowing,emergence and flowering were precipitation,sunshine and sunshine.The integrated climate suitability during whole growth stages of maize order from high to low on four cities is Chaoyang city,Fuxin city,Huludao city,Jinzhou city.（3）EOF analysis showed that the suitability degrees of whole growt h,sowing,emergence,flowering,maturity have good spatial evolution of consistency.The percentage anomaly of suitability degree of integrated climate during the whole growth,sowing,emergence,flowering,maturity period of maize in West Liaoning Province generally slightly declined in space from southwest to northeast,northwest to southwest and the eastern region,south to north,east to west and the east side to the south and north sides.Wavelet transformation analysis suggested the time coefficient of first feature vectors of whole growth,sowing,emergence,flowering,maturity integrated climate suitability degree respectively at 3 scales of oscillation period―14³0 a、8¹4 a、3⁷ a;13²4 a、4¹3 a、1⁴a;15³0a、7¹5a、3⁷a;13²1a、7¹3a、4⁷a.（4）According to the suitability degree of integrated climate during different growth stages of maize and overlay the coefficients of overlay the EOF space,to regionalize Western Liaoning base on the integrated climate suitability during whole growth stage of maize,the results show that Western Liaoning is divided into 3 levels:Highly suitable area inc ludes Zhangwu county,north of Fuxin county,Chaoyang city（Lingyuan city,Jianping county,Chaoyang county,Beipiao city and Kazuo county）,Jianchang county;Medium suitable area includes Fuxin city and Fuxin county,Yi county,south of Beizhen city,north of Linghai city,Huludao city and Suizhong county;low suitable area includes the most of Heishan county,Jinzhou city,parts of Linghai city,east of Xingcheng city.（5）Through on the spatial and temporal distribution characteristics of temperature,precipitation,sunshine and integrated climate suitability degree and soil,geomorphology properties in Western Liaoning,put forward proposals for tackle climate change and promote maize production includes:Improving varieties distribution and utilization of energy resources,strengthen artificial-irrigation in summer and autumn,increasing light intensity by reasonable density so as to guarantee strength and rate of photosynthesis,controlling the maize production area and promote agroforestry systems in Wes tern Liaoning,enhancing weather intervention by artificial to reduce the effects of severe weather on agricultural production.