四川盆地酸性紫色水稻土硝化作用的类型及氧化锰的影响

发布时间：2019-04-18 13:55

【摘要】：酸性土壤中的硝化活性存在很大空间变异,并且其硝化类型也因土壤环境条件而异。锰氧化物作为土壤矿物的一种,可能通过其生物毒性及作用土壤氮矿化等影响硝化过程。本研究在四川盆地分别采集pH为4.6,4.9两种酸性紫色水稻土,通过添加乙炔或锰氧化物,探究四川盆地酸性水稻土硝化作用的主要类型以及锰氧化物对硝化作用的影响。结果表明:酸性水稻土中存在显著的硝化活性,加入乙炔后,pH4.9空白对照和pH4.9加硫酸铵处理的两种酸性紫色水稻土的净硝化速率均显著下降,分别从0.46 mg kg~(-1)d~(-1),0.58 mg kg~(-1)d~(-1)降至-0.08 mg kg~(-1)d~(-1),-0.15 mg kg~(-1)d~(-1),证明酸性水稻土的硝化作用主要以自养硝化作用为主;pH4.6,4.9土样加入锰氧化物后,净硝化速率分别从2.07 mg kg~(-1)d~(-1),3.17 mg kg~(-1)d~(-1)下降到0.60 mg kg~(-1)d~(-1),2.71 mg kg~(-1)d~(-1),表明锰氧化物对酸性水稻土硝化作用的净效应是抑制作用,可能的原因是酸性条件下锰氧化物对硝化微生物的毒性所致。
[Abstract]:The nitrification activity in acidic soil varied greatly, and the nitrification types varied with soil environmental conditions. Manganese oxides, as a kind of soil minerals, may affect nitrification process through its biotoxicity and nitrogen mineralization. Two kinds of acidic purple paddy soils were collected in Sichuan Basin with pH of 4.6 and 4.9 respectively. By adding acetylene or manganese oxides, the main types of nitrification and the effects of manganese oxides on nitrification in acidic paddy soils in Sichuan Basin were investigated. The results showed that there was significant nitrification activity in acidic paddy soil. After acetylene was added, the net nitrification rate of two acidic purple paddy soils treated with pH4.9 blank control and pH4.9 with ammonium sulfate decreased significantly. From 0.46 mg kg~ (- 1) d ~ (- 1), 0.58 mg kg~ (- 1) d ~ (- 1) to-0.08 mg kg~ (- 1) d ~ (- 1),-0.15 mg kg~ (- 1) d ~ (- 1), The results showed that the nitrification of acidic paddy soil was dominated by autotrophic nitrification. After adding manganese oxides to pH4.6,4.9 soil samples, the net nitrification rate decreased from 2.07 mg kg~ (- 1) d ~ (- 1), 3.17 mg kg~ (- 1) d ~ (- 1) to 0.60 mg kg~ (- 1) d ~ (- 1), respectively. 2.71 mg kg~ (- 1) d ~ (- 1) showed that the net effect of manganese oxide on nitrification of acidic paddy soil was inhibited, which might be due to the toxicity of manganese oxide to nitrifying microorganisms under acidic conditions.
【作者单位】：西南大学资源环境学院;
【基金】：国家重点研发计划子课题(2016YFD0300901-02) 国家自然科学基金项目(41671232)资助
【分类号】：S153

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