气候变化对半干旱雨养农业区春小麦生长的影响

利用甘肃省定西农业气象观测站1986—2004年的观测资料，就气候变化对黄土高原半干旱雨养农业区春小麦生长的影响进行了初步探讨。结果表明，近19年来该地区气候变化呈现暖干化趋势，春小麦对气候变化的响应表现在生长季提前、生长期缩短、产量下降。相关分析也显示，降水量对春小麦生长的影响程度要高于温度。在春小麦整个生长发育过程中，其阶段生长和产量对气候变化的响应不完全一致：气候变化使该地区春小麦出苗期、拔节期、抽穗期和成熟期的出现时间均提前，而乳熟期出现时间推迟，导致播种—出苗期的营养生长阶段缩短、出苗—拔节期的营养生长阶段延长、拔节—抽穗期的生殖生长阶段缩短，抽穗—乳熟期的生殖生长阶段延长，乳熟—成熟期的生殖生长阶段缩短，最终造成全生长期缩短。出苗—拔节期、抽穗—乳熟期降水量减少对春小麦产量下降有显著的正效应（P<0.05），拔节—抽穗期的增温对产量有极显著的负影响（P<0.01）。预计随着未来全球气候进一步的变暖和半干旱区降水量的减少，将会更加严重影响春小麦的生长发育。

Impact of Climate Change on Spring Wheat Growth in Semi-Arid Rain Feed Region

Using surface observation data of Dingxi agricultural meteorological station from 1986 to 2004,the impact of climate change on spring wheat growth in semi-arid rain feed region was investigated.The results showed that in the last 19 years temperature had increased,but precipitation had decreased in this region,the response of spring wheat growth to climate change took the form that the growing season had come in advance,growth period had shortened and yield had fallen off.The correlativity analysis also revealed that the impact of precipitation on spring wheat was more noticeable than that of temperature.In the whole growth period of spring wheat,the response was different in yield and phase growing on climate change,such as the appearing time of sprouting,jointing,tasselling and maturity being ahead but milking being postponed.That is to say,it shortened the spring wheat's nutrition growth stage of seeding-sprouting,elongated the sprouting-jointing stage,cut down the generative growth in the jointing-tasselling phase,prolonged the tasselling-milking stage, and shortened the milking~maturity stage.These finally resulted in the shortening of whole growth period.It had significantly positive effect on yield due to precipitation decreasing in spring wheat's sprouting-jointing and tassellingmilking stage(P<0.05),also it had highly significant negative effect on yield due to temperature increasing in jointing-tasselling phase(P<0.01).So we expect that with the climate further warming and the precipitation reducing,it will much more seriously influence the growth of spring wheat.