CAJ | 학술논문

采用土壤淤浆方法对丹麦农田和山毛榉森林土壤反硝化过程中N2O的产生与还原进行了研究,同时考察了硝酸根和铵离子对反硝化作用的影响.结果表明,森林土壤反硝化活性大于农田土壤,但农田土壤中N2O还原活性大于森林土壤,表现在农田和森林土壤中N2O/N2的产生比率分别为0.11和3.65.硝酸根和铵离子能促进两种土壤中的N2O产生,但可降低农田土壤中的N2O还原速率.与农田土壤相比,硝酸根可降低森林土壤N2O的还原能力,而铵离子却表现出对N2O还原的促进作用.培养1周内尽管农田土壤中硝酸根始终存在,但几乎所有产生的N2O都被还原成N2.然而,只有当硝酸根几乎耗尽,森林土壤中N2O的还原才开始进行.由于两种土壤pH值的不同造成硝酸根对N2O还原抑制作用的差异,因为酸性条件下硝酸根对N2O还原的抑制较强.因此,土壤消耗大气N2O的适宜条件为厌氧,pH中性和硝酸根含量低.
채용토양어장방법대단맥농전화산모거삼림토양반초화과정중N2O적산생여환원진행료연구,동시고찰료초산근화안리자대반초화작용적영향.결과표명,삼림토양반초화활성대우농전토양,단농전토양중N2O환원활성대우삼림토양,표현재농전화삼림토양중N2O/N2적산생비솔분별위0.11화3.65.초산근화안리자능촉진량충토양중적N2O산생,단가강저농전토양중적N2O환원속솔.여농전토양상비,초산근가강저삼림토양N2O적환원능력,이안리자각표현출대N2O환원적촉진작용.배양1주내진관농전토양중초산근시종존재,단궤호소유산생적N2O도피환원성N2.연이,지유당초산근궤호모진,삼림토양중N2O적환원재개시진행.유우량충토양pH치적불동조성초산근대N2O환원억제작용적차이,인위산성조건하초산근대N2O환원적억제교강.인차,토양소모대기N2O적괄의조건위염양,pH중성화초산근함량저.
A soil-water slurry experiment was conducted to study the potentials of N2O production and reduction in denitrification of agricultural and beech forest soils in Denmark. The effects of nitrate and ammonium additions on denitrification were also investigated. The forest soil showed a higher denitrification potential than the agricultural soil. However, N2O reduction potential of the agricultural soil was higher than the beech forest soil, shown by the ratio of N2O/N2 approximately 0.11 and 3.65 in the agricultural and the beech forest soils, respectively. Both nitrate and ammonium additions stimulated the N2O production in the two soils, but reduced the N2O reduction rates in the agricultural soil slurries. In contrast to the effect on the agricultural soil, nitrate reduced the N2O reduction rate in the beech forest soil, while ammonium showed a stimulating effect on the N2O reduction activity. After one week incubation, all of the N2O produced was reduced to N2 in the agricultural soil when nitrate was still present. Nitrous oxide reduction in the beech forest soil occurred only when nitrate almost disappeared. The different nitrate inhibitory effect on the N2O reduction activity in the two soils was due to the difference in soil pH. Inhibition of nitrate on N2O reduction was significant under acidic condition. Consequently, soil could serve as a sink of atmospheric N2O under the conditions of anaerobic, pH near neutral and low nitrate content.