西藏气候变化及其对作物产量潜力的影响

Effect of climate change on yield potential of crops in Tibet

以西藏1971—2010年6个代表性气象站气象资料为依据,运用线性倾向率方法分析了近40年来西藏气候变化的特征,同时分析了6个农业主产区40年来青稞、小麦的光温与气候生产潜力的变化趋势,并结合现实生产力数据分析了青稞和小麦的增产空间。结果表明:(1)1971—2010年40年间,西藏温度和降水量均表现为升高趋势,6个农业主产区平均气温升高了2.26℃,远大于全国1.1℃·100a-1的平均气温升高速度;(2)伴随着温度的升高,青稞和小麦的光温生产潜力分别以每年53 kg·hm-2和107 kg·hm-2的速度增加,气候生产潜力也随着降水量的小幅升高而有所增加,平均每年增加94 kg·hm-2和110 kg·hm-2;(3)青稞与小麦的光温和气候生产增产空间均表现为减小的趋势,但至目前,青稞的光温和气候增产空间仍有10 385 kg·hm-2和5 969 kg·hm-2,小麦的光温和气候增产空间仍有9 040 kg·hm-2和5 197 kg·hm-2。

Based on observation data of six representative meteorological stations in Tibet during 1971 — 2010 ,and using linear trend estimation ,this study analyzed characteristics of climate change in the past 40 years in Tibet .We stud-ied the changing trends of light-temperature productivity （LTPP） and climatic potential productivity （CPP） of barley and wheat in the past 40 years from six major agriculture areas in combination with the data of actual productivity .The results showed that ：（1） In the past 40 years ,the temperature and precipitation increased ,the mean temperature increased by 2 .26 ℃ in the six major agriculture areas ,the increasing rate of mean temperature was higher than that of China （1 .1 ℃·100a - 1 ） ;（2） The LTPP of barley and wheat increased at an annual rate of 53 kg·hm - 2 and 107 kg·hm - 2 with the in-creased temperature ,respectively .The CPP increased at an annual rate of 94 kg·hm - 2 and 110 kg·hm - 2 with a slight increasing of precipitation ,respectively ;（3） The changing trend of yield potential in terms of LTPP and CPP of barley and wheat decreased .For barley ,there existed gap between the actual yield LTPP （10 385 kg·hm - 2 ） and CPP （5 969 kg·hm - 2 ） of barley ,while those for wheat were 9 040 kg·hm - 2 and 5 197 kg·hm - 2 ,respectively .