气候变暖对河西走廊绿洲灌区主要作物需水量的影响

作物需水量是农田水分循环系统中最重要的因素之一。在未来温度上升1～4℃的情景下,研究了气候变暖对我国河西绿洲灌区主要作物需水量的影响。结果表明,气候变暖对不同作物需水量的影响程度不同。其中对棉花和玉米需水量的影响最大,对小麦的影响次之。当生长期内温度上升1～4℃时,棉花需水量将增加2.17%～12.66%,相当于15.00～83.00 mm;玉米需水量将增加1.90%～11.49%,相当于14.60～82.50 mm;小麦需水量将增加1.80%～10.03%,相当于9.70～50.70 mm。气候变化对作物需水量的影响存在一定地域性差异。当增加1℃时,对干旱区武威作物需水量的影响略大于极端干旱区敦煌。当增加2℃时,武威和敦煌的作物需水量几乎相当。当增加3和4℃时,则对敦煌作物需水量的影响大于武威。根据河西绿洲灌区目前的种植结构,当温度上升1～4℃时,估算将使整个地区棉花的灌溉需水量增加0.11,0.21,0.37,0.62亿m³;玉米的灌溉需水量增加0.16,0.33,0.56,0.93亿m³;小麦的灌溉需水量增加0.14,0.26,0.45,0.71亿m³;总的灌溉需水量增加0.41,0.80,1.38,2.25亿m³。气候变暖将使河西绿洲灌区业已紧张的水资源供需矛盾更加突出。

Impact of climate change on water requirement of main crops in irrigated oasis of Hexi corridor

The crop water requirement is one of the most important factors in farmland water circulation system. study the effects of climate warming on water requirement of major crops in irrigated oasis in Hexi corridor when 1-4℃ temperature rise in the future scenarios. The results show that climate change will have great impact on water requirement of cotton and corn, followed by spring wheat. when the temperature rises 1-4℃ during the growth period, cotton, water requirement of cotton will increase by 2.17%-12.66%, equivalent to 15.00-83.00 mm; corn will increase by 1.90%-11.49%, equivalent to 14.60-82.50 mm; wheat will be increase by 1.80%-10.03%, equivalent to 9.70-50.70 mm.There are certain regional differences which the impact of climate change on crop water requirements. When the temperature increases 1℃, the crop water requirement of Wuwei in arid regions slightly larger than Dunhuang in extreme arid region; When increases 2℃, the demand almost equivalent. Dunhuang is greater than the Wuwei if increased 3 and 4℃. According to the current planting planning in Hexi Oasis, the given temperature scenario will cause an additional water requirement of 0.11,0.21,0.37,0.62 million m³ for cotton, 0.16,0.33,0.56, 0.93 million m³ for corn; and 0.14,0.26,0.45,0.71 million m³ for spring wheat. The total irrigation water increase 0.41,0.80,1.38,2.25 billion m³. Climate warming will make the situation of water shortage more severe.