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西昌地区的自然条件是比较复杂的。偏南而拔海较低的河谷地带,属亚热带气候,年平均气温20℃以上,几乎全年无霜;偏北而拔海较高的山区,气温较低,无霜期短,是高寒山区;在安宁河中上游坝区和浅山丘陵地带属温带地区,年平均气温18℃左右,无霜期约300天。在小麦整个生育期中,从有利的自然因素来看,境内气候温和,日照充足,昼夜温差较大,有利于植株养分积累。但不利的自然因素是,冬春两季干旱,蒸发量大,小麦生长期短,养分不足,特别是生育后期,在高温和大气干旱的袭击下,常不能正常灌浆结实,加之冰雹、病虫等自然灾害的影响,产量不稳定。
Xichang natural conditions are more complex. The lower reaches of the south and pull the sea valley, is a subtropical climate, the annual average temperature above 20 ℃, almost year-round frost-free; north and pull the higher the mountains in the sea, the temperature is low, frost-free period is short, is the alpine region; Anning middle and upper reaches of the dam and shallow hills are temperate regions, the annual average temperature of about 18 ℃, frost-free period of about 300 days. In the whole growing period of wheat, favorable natural factors, the territory of a mild climate, adequate sunshine, large temperature difference between day and night, is conducive to the accumulation of plant nutrients. However, unfavorable natural factors are the winter and spring drought, high evaporation, short wheat growth period, lack of nutrients, especially in late growth, under the attack of high temperature and atmospheric drought, often can not be grouted well, coupled with hail, pests and diseases Other natural disasters, the output is unstable.