施氮水平对中温带典型白浆土微生物学特性的动态影响

发布时间：2018-05-31 03:17

本文选题：施氮量 + 白浆土　；参考：《华南农业大学学报》2017年02期

【摘要】：【目的】结合玉米生育的关键时期,通过施氮水平的调控探究白浆土微生物学特性的规律变化。【方法】以玉米试验田为研究对象,通过不同施氮水平(0、150、200和250 kg·hm~(-2))的设置,研究中温带典型白浆土微生物生物量碳、氮以及脲酶、碱性磷酸酶、蛋白酶和过氧化氢酶活性对当季玉米生产过程不同施氮水平的动态响应。【结果】尿素的施入能够在玉米苗期激活释放脲酶相关的微生物,使脲酶活性增强,其作为底物,较低用量更易获得玉米拔节期较高的脲酶活性;在玉米苗期,施氮量增加有利于碱性磷酸酶活性的提升;随玉米的生长,施氮使碱性磷酸酶活性明显下降,不施氮反而会使该酶活性有所提升;尿素添加在起初阶段并不利于过氧化氢酶活性的改善,但随玉米的生长,不同施氮水平下过氧化氢酶活性均呈增加趋势;在玉米苗期,随施氮水平增加,蛋白酶活性也增加,但当施氮量增至250 kg·hm~(-2)时,蛋白酶活性有所降低;当玉米成熟后,不施氮和低量施氮更有利于蛋白酶活性的提升。尿素基施能够在玉米苗期降低微生物生物量碳(MBC)的水平,但随玉米的生长,施氮有利于MBC的保蓄和稳定;不施氮或过量施氮均有助于白浆土微生物生物量氮(MBN)的提升,而适量供氮则更利于其周转,向植物可利用的方向转化。【结论】集中过量施用尿素不利于土壤生物肥力的保蓄,综合考虑玉米产量及培肥效应,白浆土适宜的氮素用量应为200 kg·hm~(-2)。
[Abstract]:[objective] to explore the changes of microbiological characteristics of alpine soil through the regulation and control of nitrogen application level in the key stage of maize growth. [methods] the experiment field of maize was used as the research object, and the setting of different nitrogen application levels of 0 150200 and 250 kg / hm ~ (-1) ~ 2 ~ (2 +) was used to investigate the changes of microbiological characteristics of alpine soil. The study of microbial biomass carbon, nitrogen, urease, alkaline phosphatase, The dynamic response of protease and catalase activity to different nitrogen levels during maize production. [results] Urea application could activate and release urease related microorganisms at seedling stage of maize and increase urease activity as substrate. It is easier to obtain higher urease activity at jointing stage of maize at lower dosage, and the increase of nitrogen application amount is beneficial to the increase of alkaline phosphatase activity in seedling stage of maize, and the alkaline phosphatase activity decreases obviously with the growth of maize. The catalase activity was not improved by adding urea at the initial stage, but increased with the growth of maize. The protease activity increased with the increase of nitrogen application level, but decreased when the nitrogen application increased to 250kg / h ~ (-2), but when corn matured, the increase of protease activity was more beneficial to the increase of the protease activity without nitrogen application and low nitrogen application. Urea application could reduce the level of microbial biomass carbon (MBCs) in maize seedling stage, but with the growth of maize, nitrogen application was beneficial to the preservation and stability of MBC, and no or excessive application of nitrogen could improve the microbial biomass nitrogen (MBCs) in albic soil. But the proper amount of nitrogen supply is more favorable to its turnover and transformation to the direction of plant utilization. [conclusion] concentrated and excessive application of urea is not conducive to the conservation and storage of soil biological fertility, and the corn yield and fertilization effect are considered comprehensively. The suitable amount of nitrogen should be 200 kg / hm ~ (-2).
【作者单位】：吉林农业科技学院植物科学学院;中国农业大学农学院;
【分类号】：S154.2;;S158.5

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