| Based on the daily meteorological data of 70 stations and production data of maize in Northeast China from 1961 to 2006,the changing characteristics of climate change and climatic resources change of maize in Northeast China were analyzed,the primary climatic factors influencing maize yield in different region were studies by the method of Baler yields models, and indexes of chilling damage to maize for climate warming in Northeast China were made using previous methods.Finally suggestions about sustainable development of maize in Northeast China were put forward.The primary conclusions were:(1)The annual mean air temperature increased by 0.36℃per decade in Northeast China in the last 46 years,which was faster than that of China in the last 54 years,and the warming trend of seasons from high to low were winter,spring,autumn and summer.Geographically,warming trend in Heilongjiang Province was very significant,followed by Jilin Province and Liaoning Province.Significant warming process occurred in the late 1980s.The warming rates of minimum and maximum air temperature were respectively 0.51℃/10a and 0.24℃/10a,and the former was as two times as the latter.The precipitation had a slowly decreasing trend,and sunshine hours decreased by 0.11 h per decade.(2)In 2001-2006 planting date came earlier 2～10 days than the 1960s in the fitting districts for maize growing.Distribution line of different maize variety moved obviously toward east and north in 2001-2006.The line of late-maturing variety moved north ward the south part of Songnen Plain,and east ward the center area of Jilin Province.Early-maturing variety could be planted some areas in Changbai Mountains which were lack of heat condition for maize growing before 2000.Medium-maturing variety and medially late-maturing variety were planted in Sanjiang Plain,and extremely early-maturing variety was also planted in Xiaoxing'an Mountains.(3)With air temperature increased,the m eteorological yield of maize increased in Heilongjiang Province,and the eastern and western part of Jilin Province.The m eteorological yield of maize was negative relation with precipitation in the center area of Jilin Province,and had a correlation with precipitation and sunshine hours in Liaoning Province.(4)When anomaly of the sum of mean air temperature from May to September was less than or equal to -3.6℃,it was defined serious chilling damage year to maize in Changchun station,and -2.7℃was regard as division of chilling damage year.Analyzed indexes of chilling damage to maize in different area of heart condition showed that frequency and intension of chilling damage in area of low heart condition were obviously reduced with climate wanning.(5)Heart resources were increasing with climate warming,but the trend of drought development was also worse in Northeast China.Focusing on adjusting planting date and variety, in the meantime,enhancing water conservancy project,extent of dry land fanning techniques, and selecting drought tolerance,resistances to diseases,anti-stress maize varieties were sustainable development strategies of maize. |
