自由空气CO2浓度升高对水稻营养元素吸收和籽粒中营养元素含量的影响

 利用FACE（Free Air Carbon Dioxide Enrichment）平台技术，用水培试验研究了低氮（14 mg/L）和常氮（28 mg/L）水平下，大气CO2浓度升高对水稻（Oryza sativa L.）N、P、K、Ca、Mg、Cu、Zn、Fe、Mn的吸收和在植株不同部位的分配，并着重分析了CO2浓度升高对稻米中营养元素含量的影响。结果表明，按照当前CO2浓度条件下营养元素的正常供应水平，而且各元素都以有效态供给时，CO2浓度升高对多数被测元素吸收总量影响不大，只增加了K、Ca、Fe的吸收总量； N、P、Mg、Mn向穗部分配增加，K、Ca、Cu、Zn、Fe向穗部的分配比例不变；水稻籽粒中P、Ca、Mg、Cu、Zn、Fe和Mn含量无显著影响，N、K含量显著下降。还初步探讨了CO2浓度升高对稻米中人类必需营养元素的不足（或“隐性饥饿”）的影响。

Effects of Elevated pCO2 on Nutrient Uptake by Rice and Nutrient Contents in Rice Grain

Nutrient uptake and distribution in different tissues of rice (Oryza sativa L.) and nutrient contents in grain at low N (14 mg/L) and normal N (28 mg/L) were studied under ambient air and elevated atmospheric pCO₂ (Ambient+200 μmol/mol) by the China FACE (Free-Air Carbon-Dioxide Enrichment). Supplied with available forms of nutrients at current normal level, rice uptook more K, Ca, Fe under elevated pCO₂ treatment. N, P, Mg, Mn but not K, Ca, Cu, Zn, Fe distribution in panicle increased due to elevated pCO₂ treatment. P, Ca, Mg, Cu, Zn, Fe, Mn contnets in rice grain remained unaffected while N, K contents declined significantly under elevated pCO₂ treatment. Effect of elevated pCO₂ on the possible “hidden hunger” in rice grain was also discussed.