选择地处中国亚热带和暖温带生态地理分界线(秦岭—淮河)的信阳地区,利用1992-2012年信阳冬小麦从播种到各生长发育期大于0℃活动积温数据和1951-2013年气温、降水量月值数据,主要运用Morlet小波分析方法,分析信阳地区冬小麦在出苗、分蘖、返青、拔节、抽穗、乳熟六个生长发育阶段的活动积温和气温序列的多时间尺度变化规律.信阳地区近60a的增温速率达到0.18℃/10a,平均气温变暖幅度约为1.1℃,上世纪90年代中期开始增温较为显著;信阳地区近60a的降水量变化较为平稳,没有明显的增减趋势,降水变率为20%;这些特征与中国及全球同期的变化特征较为相似.信阳地区近60a冬小麦各生育阶段大于0℃活动积温时间序列和气温时间序列都存在着明显的多尺度震荡周期,存在着复杂的多重时间尺度的嵌套结构;各生育阶段积温时间序列存在着2a为周期的高频震荡和4~6a为周期的低频震荡,这些尺度的震荡周期信号强弱不等.研究对提高气候敏感区冬小麦产量、降低病虫害风险及应对旱涝等极端气象灾害有一定的现实意义.
Xinyang region is located at the subtropical and warm temperate zone of China ecological geographic boundaries which is from Qinling mountains to Huai river.The Active accumulated temperature〉0 ℃ data of winter wheat growth period during 1992-2012,and the temperature and precipitation data during 1951-2013 were used;the wavelet analysis method was used;the changing rule of winter wheat growth was analyzed.The cycle characteristics of growth period signal were concluded based on the wavelet analysis results of the six periods:emergence,tiller,spring,jointing,ear and milky.The linear warming trend over the last 60 years was 0.18℃ per decade in Xinyang area,and annual mean air temperature in Xinyang area as a whole rose by about 1.1℃for the last 60 years,especially the air temperature increased quickly since the middle of 1990 s.Annual precipitation was stable in last 60 years,and variable rate was about 20%;the variation characteristics of air temperature and precipitation in Xinyang area were similar to the China and the world in last 60 years.The active accumulated temperature time series and air temperature time series had multi-scale oscillation periods in Xinyang in last 60 years,and the multi-scale oscillation periods had nested structure and complex variation characteristics.The active accumulated temperature time series of every growth period existed high frequency oscillation about 2years and low frequency oscillation about 4-6years,and the intensity of these oscillation periods signal were complex.The study provides guidance for raising winter wheat production and preventing meteorological disasters in the temperate-subtropical ecotone.