东北地区玉米大豆水分利用效率研究

利用大安和朝阳玉米研究站点、呼玛和锦州大豆研究站点近20 a作物产量、发育期及土壤水分实测资料,同时结合分期播种试验资料,研究了玉米大豆产量水分利用效率(WUE_g)对降水、温度的响应特征,分析了两种作物产量水分利用效率与群落水平水分利用效率(WUE_b)的关系。结果表明:大安和朝阳站点玉米WUE_g分别为1.75±0.47 kg·m~(-3)和1.98±0.72 kg·m~(-3),呼玛和锦州站点大豆WUE_g分别为0.63±0.35 kg·m~(-3)和0.55±0.18kg·m~(-3);玉米站点WUE_g与播种—成熟期间的降水量和ET均呈显著的二次曲线关系(P0.05),WUE_g与温度关系不明显;大豆WUE_g与播种至成熟期间的降水量呈现显著的负相关关系;历史资料分析结果表明,随着生育期期间平均气温的增加,大豆WUE_g升高;在大安和朝阳站点,取得高水分利用效率与获得高产所消耗的水量(即ET)并不一致,表明对于存在干旱胁迫的半干旱和半湿润区,有效的利用水(Effective use of water,EUW)而不是一味追求水分利用效率(WUE)是提高产量的有效途径,植物消耗的水量(ET)往往是决定作物产量的重要因素。

Research on water use efficiencies of maize and soybean in northeast China

Based on data in recent 20 years about crop production ,developmental period ,and soil water content collected from the agro-meteorological experiment sites at Da’an and Chaoyang (maize sites) ,and Huma and Jinzhou (soybean sites) in northeast China ,as well as the trail results by periodic seeding ,response of grain water use efficiency (WUEg ) to precipitation/temperature and also the relationship between WUEg and water use efficiency at the level of biomass (WUEb ) were analyzed .The results showed that the average maize WUEg in multi-years at Da’an and Chaoyang were 1 .75 ± 0 .47 kg·m-3 and 1 .98 ± 0 .72 kg·m-3 ,respectively ,and soybean WUEg at Huma and Jinzhou were 0 .63 ± 0 .35 kg·m-3 and 0 .55 ± 0 .18 kg·m-3 ,respectively .For maize ,the relationship between WUEg and precipitation during planting to harvest exhibited a quadratic function at a significant level of P<0 .05 .The relationship between WUEg and mean temperature during growing period showed no obvious pattern .For soybean ,WUEg was significantly neg-atively correlated with precipitation during growing period .Results from historic data showed that soybean WUEg was ele-vated with the increase of mean temperature during growing period ,although the correlation between them was not signifi-cant .In addition ,at Da’an and Chaoyang areas ,high WUEg did not agree with the water consumption for high yield , suggesting that in semi-arid and semi-humid regions under drought stress ,effective use of water (EUW ) but not water use efficiency was the critical factor to determine crop yield .It can be concluded that water use is the main (not the exclu-sive ) drive of yield under drought stress .