气候生长季是植物生长发育可能进行的理论时段,有针对性地评估不同植被类型区生长季时空变化特征具有很强的指示意义和应用价值。基于内蒙古1961-2010年46个气象站点的日平均气温资料,采用线性回归与Mann-Kendall(M-K)趋势性检验法探讨近50 a来内蒙古不同植被类型区生长季时空特征。结果显示:近50 a 来,内蒙古荒漠区生长季延长最明显,年际波动最大,分别为22 d和13 d;草原区生长季延长约14 d,以生长季初日提前为主(75%),且由东向西延长幅度增加,年际波动加大;而农业、森林区生长季长度分别增加17 d 与15 d,生长季初日提前与终日推迟幅度相差不大,年际波动小。气候变暖背景下生长季延长不仅可以保证农作物具有较充分的生长时间,而且也将促使高产、优质的晚熟作物品种种植范围扩大。
英文摘要:
The climatic growing season is the stable period through the thresholds of daily mean temperatures, viewed as the entire stage in which growth can be theoretically take place. Assessing its spatio-temporal characteristics of different vegetation zones specifically may have an useful meaning and have several important climatological applications. The paper investigated the temporal and spatial changes of the growing seasons in different vegetation zones using mean air temperature data recorded at 46 stations in Inner Mongolia,China,over the period 1961-2010. Mann-Kendall trend test and linear regression method are also used to detect the significance and the magnitude of the growing season change,respectively. Results show that the length of the growing season in desert zone had the maximum extension and inter-annual fluctuation over the past 50 years,with the amount of 22 days and 13 days respectively. In grassland zone,the length has increased by approximately 14 days,mainly owing to an earlier onset in spring(accounting for 75%),and the magnitude of increase became larger from east to west,with an rising inter-annual fluctuation. While the length in agriculture and forest regions were about 17 days and 15 days,respectively, with almost identical rates of an earlier onset in spring and a delayed end in autumn. The results also suggest that a continuous advancing trend of the growing season may provide opportunities for planting earlier,ensure crop maturation, and promote planting range of high-yield and fine quality crops extending,but the options should be taken timely and scienti-cally to cope with ongoing climate change,based on the characteristics of the growing season fluctuations over the 50 years.