北方农牧交错带东段生长季气候变化与温水组合规律研究

Research on climate changes and combinational law of temperature and precipitation during growing season in the eastern ecotone between agriculture and animal husbandry in Northern China

北方农牧交错带东段是生态脆弱区,以雨养农业为主,作物产量受气候影响波动大.利用5个气象站近半个世纪的逐日气温与降水资料,使用墨西哥帽函数(MHF)小波、Mann-kendall非参数检验统计方法,研究了生长季内气候变化及温水组合规律.结果表明:≥10℃积温和生长季降水的振荡周期基本吻合,暖干与冷湿气候交替出现.生长季≥10℃积温的上升趋势达到显著水平(P<0.05),增加幅度为每10年72℃;降水的下降趋势不显著(P>0.05),全年降水和生长季降水变化为每10年-17.2 mm和-13.7 mm.≥10℃的初终日有明显的提前和滞后性.≥10℃积温充足,生长季降水占全年的88%.生长季降水分配极不均衡,雨热配合较好.

Eastern ecotone between agriculture and animal husbandry in northern China is an eco-fragile region.Agricultural production depends upon rainfall.Crop yield has a ＂wave＂ style derived by climate changes.Based on the date of daily temperature and precipitation from five meteorological stations for the last 50 years in the eastern ecotone between agriculture and animal husbandry in northern China,making use of MHF wavelet analysis,non-parametric statistic test method of Mann-kendall,the research analyzes climate change and combinational law of temperature and precipitation during growing season.The result provides the scientific foundation for ensuring optimal combination between crop productivity and climatic resource and agricultural sustainable development in the eastern ecotone between agriculture and animal husbandry in northern China in the background of global climate change.The results show that periodoscillation is basically similar to ≥10℃ accumulated temperature and precipitation of growing season;the variations of ≥10℃ accumulate temperature and precipitation contain obvious staggered features.The increasing trend of ≥10℃ accumulate temperature is significant,the increasing ratio is 72℃ per 10-year.The decreasing trend of annual and growing season precipitation is not significant,the decreasing ratio is 17.2 mm and 13.7 mm per 10-year.The characteristics of advanced and laged is obvious relate to the first and last day of ≥10℃ accumulate temperature.≥10℃ accumulate temperature is adequate,the precipitation of growing season accounts for 88% of all annual precipitation.The distribution of the precipitation of growing season is quite unbalanced.Precipitation and quantity of heat are in perfect accord with each other.