棉秆炭对灰漠土玉米生长及氮素利用的影响

通过盆栽试验,氮素设置3个水平,棉秆炭用量占土壤质量分数设置4个不同水平,研究棉秆炭对玉米生长及氮素利用的作用效果。结果表明,不施氮肥(N0)处理,添加棉秆炭抑制玉米器官的生长和生物量积累,生物量降低幅度为4.98%~17.36%;氮肥与棉秆炭配施提高玉米器官的生长和生物量积累,提高幅度为1.68%~11.30%,不同棉秆炭处理间差异不明显。添加棉秆炭促进玉米根系生长,提高根冠比,增加氮素对玉米根冠比的影响不明显;同时,添加棉秆炭抑制玉米根、茎、叶、棒以及植株吸氮量,增加施氮量抑制作用逐步降低。施入棉秆炭降低氮肥吸收效率,提高氮肥表观利用率,相比不添加棉秆炭(BC0)处理,添加2.0%棉秆炭(BC2.0)处理氮肥吸收效率降低2.50%和4.96%,氮肥表观利用率提高8.48%和7.49%,过量的棉秆炭添加可能降低氮肥表观利用率。

Effect of Biochar on the Nitrogen Absorption and Maize Growth in Grey Desert Soil

By three nitrogen levels of N and four levels of cotton stalk biochar account for mass fractions of soil to study the action effect of cotton stalk biochar and nitrogen on crop growth and nitrogen absorption The results showed that the growth of maize organs and biomass accumulation was suppressed by the addition of cotton stalk bio-char, and the decrease in biomass accumulation ranged from 4.98% to 17.36% compared with the treatment of no ni-trogen fertilizer, while the growth of maize organs and biomass accumulation were increased with nitrogen fertilizer and cotton stalk biochar, and increase from 1.68% to 11.30%, but the difference was insignificant. Cotton stalk bio-char promote growth of maize root and increase the root-shoot ratio, and has no obvious on root-shoot ratio with ni-trogen fertilizer applied. The nitrogen uptake of root, stem, leaf, corn cob and maize plants were suppressed by the addition of cotton stalk biochar, and the inhibition of nitrogen uptake decreased gradually with increase of nitrogen fertilizer applied. Cotton stalk biochar applied reduce nitrogen recovery efficiency and increase nitrogen apparent ef-ficiency, and nitrogen recovery efficiency of BC2.0 decreased by2.50% and 4.96% compared with treatment of BC0, and nitrogen apparent efficiency increased by 8.48% and 7.49%, and reduced nitrogen apparent efficiency in excess of cotton stalk biochar applied.