淹水胁迫对不同土壤类型养分及玉米苗期养分吸收分配的影响

Effects of Waterlogging Stress on Available Nutrients and Maize Nutrient Absorption and Distribution in Different Soil Types at Seedling Stage

采用池栽试验,以潮土和砂姜黑土为对象,研究淹水胁迫下不同土壤类型速效养分变化及玉米苗期养分吸收分配的特征。结果表明,淹水胁迫导致两类土壤速效氮含量显著下降,随着淹水时间延长降低幅度增大;土壤速效磷含量呈倒抛物线型,在淹水3 d达最低值;速效钾含量呈上升趋势,潮土速效钾含量呈曲线上升趋势,砂姜黑土速效钾含量呈线性增加趋势。玉米养分及干物质的累积量和产量随着淹水时间延长而降低,氮、磷、钾的累积量分别降低21.37%～72.22%、22.00%～42.10%和11.71%～60.36%;干物质的累积量下降37.49%～57.17%;玉米产量下降9.05%～30.15%,砂姜黑土的下降幅度大于潮土。淹水减少了叶片和茎秆的养分及干物质累积量,增加了茎秆中的养分和干物质分配比例,平均增加25.95%和43.34%。

The pool experiment with two soil types（fluvo-aquic soil, lime concretion black soil） was conduct-ed to investigate changes of soil available nutrient and maize nutrient uptake and distribution under waterloggingstress at seedling stage. The results showed that waterlogging caused available N content decreasing significantly intwo soil types, and the more decreasing with longer waterlogging. The content of available P in two soil types showedan inverted parabola, and reached the lowest value at the 3 rd day of waterlogging. The available K content was ＂up-down-up＂ curve in fluvo-aquic soil, and it was increasing with extend of waterlogging in lime concretion black soil.The nutrient and dry matter accumulation and yield of maize decreased significantly with prolong of waterloggingtime, the accumulation of N, P and K was decreasing respectively by 21.37%-72.22%, 22.00%-42.10% and11.71%-60.36%, the accumulation of dry matter decreased by 37.49%-57.17%, and yield decreased by 9.05%-30.15%. The decreasing in fluvo-aquic soil was higher than that in lime concretion black soil. The nutrient and drymatter accumulation of leaves and stems was reduced, but the proportion of nutrients and dry matter in stems was in-creased under waterlogging stress by 25.95%and 43.34% in average.