陇东黄土高原农业物候对全球气候变化的响应

通过对多年来陇东黄土高原董志塬主要农作物冬小麦和主要果树苹果、梨发育物候和气候变化的同步观测,分析了陇东黄土高原农作物发育物候对气候变化的生态响应。分析发现,董志塬近35年来年平均气温呈显著增加的趋势,且以冬季和春季增温为主(冬小麦越冬期增温线性趋势达0.0672℃a/),和全球气候变暖趋势基本一致。增温线性趋势达0.0507℃a/,远高于全国20世纪60年代以来平均增温幅度,也高于陇东黄土高原近35年平均增温幅度(0.0348℃a/),是陇东黄土高原增温中心地带。气候变暖对董志塬冬小麦和果树的生态影响主要体现在春季发育期普遍提前,冬小麦越冬期显著缩短(缩短的线性趋势达0.674d a/),而冬小麦和果树春季各发育期间隔并未出现缩短的趋势。而且由于当地种植冬小麦品种为强冬性、长日照型品种,发育期提前导致日长缩短,对发育有一定抑制作用,抵消了一部分增温的影响,因此果树春季各发育期提前的线性趋势比冬小麦明显。就果树而言,梨树春季发育期提前的线性趋势又比苹果树明显。结论认为气候变化对农业的影响有利有弊,农业管理部门应根据当地气候变化特征,及时调整种植结构,优化种植模式,趋利避害,充分挖掘气候资源潜力,提高农业经济效益。

Response of Agricultural Phenospectrum to Global Climate Change in Loess Plateau of East Gansu Province

According to years of synchronous observations of growth spectrum of Dongzhiyuan main crops(e.g.winter wheat) and main fruit trees(e.g.apple,pear) and climatic change,this paper analyzes the ecological response of crop growth spectrum to the climatic change in Loess Plateau of east Gansu province.The result indicates that the mean annual temperature has presented an increasing trend notably in the last 35 years in Dongzhiyuan,and dominated by winter and spring warming(winter wheat over-wintering period temperature increase linear trend reaches 0.067 2℃/a),basically identical with the warming trend of global climate.It reaches 0.050 7℃/a,which is much higher than the mean national temperature increase range since the 1960s and also higher than the Loess Plateau in east Gansu province(0.034 8℃/a) in the last 35 years.It is also the central area in temperature increase in the study area.This further confirms that the eastern part of Northwest China is one of the regions witnessing greater temperature increase range.The impact of climate warming on ecology of winter wheat and fruit tree ia mainly reflected in advance in growth stage generally in spring in Dongzhiyuan and winter wheat over-wintering stage shortens notably(the shortened linear trend reaching 0.674d/a).However,winter wheat and fruit tree growth intervals at various phases do not present shortening trend.And because the locally plant winter wheat variety is strong winter enduring and long sunshine tolerate variety,the advancement in growth period causes the shortening of sunshine time,restricts crop or plant growth to a certain degree and offsets partly,the temperature increase effect.Therefore,the linear trend of fruit tree puberty in advance in spring is more obvious than the winter wheat.With regard to fruit tree,the linear trend of puberty of pear tree in advance is more obvious than the apple tree in spring.The conclusion is that the impact of climatic change is both advantageous and disadvantageous to agriculture.So the relevant agricultural administrative department should follow the local climatic change characteristics to adjust the cropping pattern in time,optimize the mode of planting,go after profits and advoid disadvantages,fully excavate the resource potentiality of the climate and improve the agricultural economic benefits.