升温和大气CO2浓度升高对不同品种小麦养分吸收的影响

研究升温和大气CO_2浓度升高对不同品种小麦养分吸收的影响,为未来气候变化下农田土壤养分管理与作物施肥提供科学参考。在田间开放条件下模拟升温和大气CO_2浓度升高,设置对照(CT)、大气CO_2浓度升高(C+T)、升温(CT+)以及两者同时升高(C+T+)4个处理。每个处理种植扬麦16、苏麦188、鑫农518和镇麦9号4个品种。收获时测定小麦籽粒和秸秆中N、P、K、Ca和Mg的浓度,并计算各养分在籽粒和秸秆间的分配比例。结果表明:大气CO_2浓度升高增加了N、K、Ca和Mg在小麦地上部分的总吸收量,其中N、K和Mg的总吸收量受到大气CO_2浓度升高和小麦品种的共同影响,但是大气CO_2浓度升高没有改变养分在小麦籽粒和秸秆间的分配。升温显著降低了各养分在地上部分的总吸收量,此外升温还提高了K、降低了Ca在籽粒中的分配比例。升温和大气CO_2浓度升高下,小麦养分吸收总量变化一方面与生物量有关,另一方面与各养分含量(浓度)相关。大气CO_2浓度升高显著降低了小麦籽粒和秸秆中P的含量,但是对籽粒N、Mg和秸秆N、P、K含量的影响都与品种有关。升温降低了小麦秸秆K和籽粒P、K、Ca、Mg的含量,其中只有P的吸收对升温的响应受品种的影响。升温和大气CO_2浓度升高改变了小麦养分吸收过程,而且大气CO_2浓度升高对小麦养分吸收过程的改变与养分类型和作物品种密切相关。因此,未来气候变化下有必要根据小麦品种选择合理的培肥和管理方式。

Effects of warming and atmospheric CO2 enrichment on nutrient uptake of different wheat varieties

The objective of this study was to investigate the effect of warming and atmospheric CO₂ enrichment on the nutrient uptake of different wheat varieties. The results could provide a scientific reference for soil nutrient management and crop fertilization under future climate change. This study was carried out in an open field experiment station, where crop canopy warming and atmospheric CO₂ enrichment were simulated. Four treatments were designed, including the control(CT), atmospheric CO₂ enrichment(C+T), warming(CT+), and both (C+T+). Four varieties of wheat, including Yangmai 16, Sumai 188, Xinnong 518, and Zhenmai 9, were grown. The concentrations of N, P, K, Ca, and Mg in the wheat grain and straw were determined by harvest and the nutrient content ratio of the grain and straw was calculated. Atmospheric CO₂ enrichment increased the total uptake of N, K, Ca, and Mg of wheat. The total uptake of N, K, and Mg was affected by both atmospheric CO₂ enrichment and wheat variety. However, atmospheric CO₂ enrichment did not affect the distribution of nutrients between wheat grain and straw. Warming significantly reduced the total uptake of nutrients in the wheat. In addition, warming also increased the distribution ratio of K in the grain and reduced the distribution ratio of Ca in the grain. Under warming and atmospheric CO₂ enrichment, the change in total nutrient uptake of wheat was not only related to plant biomass but also to the nutrients'' concentration. Atmospheric CO₂ enrichment reduced the concentration of P in wheat straw and grain. The effect of CO₂ enrichment on the concentration of N and Mg in the grain as well as N, P, and K in the straw was also related to the wheat variety. Warming reduced the concentrations of K in straw and P, K, Ca, and Mg in the grain, while the response of the P uptake to warming was affected by the variety. Therefore, it was determined that warming and atmospheric CO₂ enrichment altered the nutrient absorption process of wheat and that these changes were closely related to nutrient types and crop varieties. Therefore, soil fertilization and management need to be adjusted according to crop varieties under a changing climate.