西北干旱半干旱区春小麦生长对气候变暖响应的区域差异

对分别位于西北特干旱、干旱、半干旱3种主要气候类型区的敦煌、武威（1981—2005年）、定西3个农业气象观测站(1986—2005）年的气候变化对春小麦各个物候期及其产量的影响进行分析，结果显示：不同台站的气候变化模式在时间和空间上都不同，武威和定西的气温增加而降水量减少，气候均呈现暖干化趋势，但前者的变化量大于后者。所不同的是敦煌站的气温和降水量都呈增加趋势。相关分析结果，一方面显示了在不同的气候类型区，影响春小麦生长的主导因子不同，影响敦煌、武威、定西3站春小麦生长期天数和产量的主导气象因子分别为≥0℃积温、日均温、降水量。另一方面也显示了同一气象因子对不同地区作物的影响程度、强度和方向都不同，日均温的增加对不同地区春小麦生长期的负效应表现为武威＞敦煌＞定西；≥0℃积温对春小麦生长期和产量的正效应表现为敦煌＞定西，对武威春小麦的生长期有正影响，而对产量有负影响；降水量对半干旱雨养农业区定西春小麦生长期和产量的正影响最大且极为显著（P＜0.01）；日照时数对不同地区春小麦整个生长期和产量的正影响敦煌＞定西＞武威。气候变化最终导致敦煌站春小麦的产量以8.8 g/（m2·a）的速率显著增加，武威、定西受气候暖干化的影响，春小麦产量分别下降0.3 g/（m2·a）、5.5 g/（m2·a）。造成这些差异的主要原因可能是各地的气候条件不同，其次是各地的栽培条件、田间管理（如灌溉、施肥、病虫害防治）等非气象因子的不同所致，各地作物的生长及产量形成都是气象因子和非气象因子共同作用的结果。 HT5H]关〓键〓词：HT5K]区域差异；响应；气候变暖；春小麦  HT5H]中图分类号：P463.2;S162.5〓〓〓文献标识码：AHT5SS]HK]

Regional Diversity in Response of Spring Wheat Growth on Climate Change in Arid or Semi-arid Areas

Using surface observation data of Dunhuang, Wuwei, Dingxi agricultural meteorological stations from 1981(1986) to 2005, where lie in the hyper arid, arid, semi arid areas in northwest of China respectively, the impacts and their regional diversities of climate change on spring wheat growth and yields were investigated. The results showed that in about last 20 years or so, the climate change patterns were diverse both spatially and temporally in these stations. The temperature had increased and precipitation had decreased at Wuwei and Dingxi stations, but both of them increased at Dunhuang station. The correlativity analysis also revealed that the dominant factor of influence on spring wheat growth was different. In this study, at Dunhuang, Wuwei, Dingxi stations, the dominant influence factors were ≥0 accumulated temperature, daily mean temperature, and precipitation respectively. On the other hand, the direction, degree and intensity of influence of the same climate factor on crop growth and yields were also distinct in different regions. Owing to climate change, the yields of spring wheat increased significantly by 8.8 g/(m2·a） at Dunhuang station. However, at Wuwei and Dingxi stations, it decreased by 0.3 g/(m2·a）, 5.5 g/(m2·a） respectively. These differences could be attributed mainly to the different local climate conditions, secondly to the dissimilar non climatic factors such as cultivate, management (irrigation, fertilization, disease and pest controlling) etc. The growth and yields in different regions were formed by the joint influence both climatic and non climatic factors.