CAJ | 학술논문

[目的]评价硝化反硝化作用在果园土壤氮素损失中的贡献率以及N20的排放量和排放特性。[方法]在室内培养条件下比较研究了3种不同园龄果园土壤及未开垦土壤之间硝化反硝化活性的差异。[结果]培养26天的未开垦土壤、5年、12年和20年园龄果园土壤的氮肥硝化率分别为6．85％、10．26％、13．29％和12．90％。4种土壤硝化活性均相对较低，但随种植年限的延长呈提高趋势，而且与土壤有机质和铵态氮含量呈显著正相关关系（P〈0．05），与全氮含量呈极显著正相关关系（P〈0．01），与土壤碳氮比呈显著负相关关系（P〈0．05），与pH值呈极显著负相关关系（P〈0．01）。3种果园土壤N：0排放量显著高于未开垦土壤（P〈0．05），其中硝化作用产生的N2O排放量占施氮量的0．03％～0．08％。硝化过程产生的N2O排放量与土壤有机质、全氮、铵态氮含量呈显著正相关关系（P〈0．05），而与土壤碳氮比呈显著负相关系（P〈0．05），与pH值呈极显著负相关关系（P〈0．01）。不同园龄果园土壤之间氮肥的反硝化活性差异显著，表现为20年〉12年〉5年〉未开垦土壤，反硝化损失氮量占施氮量的0．01％-3．11％，与土壤有机质含量呈显著正相关关系（P〈0．05）。[结论]我国南方果园土壤硝化水平相对较低，但随种植年限的延长呈提高的趋势；而土壤反硝化水平相对较高，而且随种植年限的延长显著提高。
[목적]평개초화반초화작용재과완토양담소손실중적공헌솔이급N20적배방량화배방특성。[방법]재실내배양조건하비교연구료3충불동완령과완토양급미개은토양지간초화반초화활성적차이。[결과]배양26천적미개은토양、5년、12년화20년완령과완토양적담비초화솔분별위6．85％、10．26％、13．29％화12．90％。4충토양초화활성균상대교저，단수충식년한적연장정제고추세，이차여토양유궤질화안태담함량정현저정상관관계（P〈0．05），여전담함량정겁현저정상관관계（P〈0．01），여토양탄담비정현저부상관관계（P〈0．05），여pH치정겁현저부상관관계（P〈0．01）。3충과완토양N：0배방량현저고우미개은토양（P〈0．05），기중초화작용산생적N2O배방량점시담량적0．03％～0．08％。초화과정산생적N2O배방량여토양유궤질、전담、안태담함량정현저정상관관계（P〈0．05），이여토양탄담비정현저부상관계（P〈0．05），여pH치정겁현저부상관관계（P〈0．01）。불동완령과완토양지간담비적반초화활성차이현저，표현위20년〉12년〉5년〉미개은토양，반초화손실담량점시담량적0．01％-3．11％，여토양유궤질함량정현저정상관관계（P〈0．05）。[결론]아국남방과완토양초화수평상대교저，단수충식년한적연장정제고적추세；이토양반초화수평상대교고，이차수충식년한적연장현저제고。
[Objective] The aim was to investigate the differences in nitrification and denitrification activities and the N20 emission of orchard soils cultivated for different periods of time. [Method] Incubation experiment was conducted to determine the ni- trification and denitrification activities and N20 emission of three types of orchard soil samples that had been cultivated for 5, 12 and 20 years, respectively, by using the virgin soil sample as control. [Result] After 26 d of incubation, the nitrification rates of nitrogen fertilizer in the virgin soil sample and the orchard soil samples cultivated for 5, 12 and 20 years were 6.85%, 10.26%, 13.29% and 12.90%, respectively, which were positively correlated with content of soil organic matter, ammonium nitro- gen and total nitrogen （P〈0.05）, and negatively correlated with soil carbon-nitrogen ratio and pH value （P〈0.05）. The denitrification activities of these soil samples in- creased with the increase of cultivation years. The amount of nitrogen loss by deni- trification accounted for 0.01%-3.11% of the amount of fertilizer nitrogen, and had a positive correlation with the content of soil organic matter （P〈0.05）. The N20 emis- sions of orchard soil samples were higher than that of the virgin soil samples （P〈 0.05）. [Conclusion] In South China, the nitrification activity of orchard soil is relatively low, but it has a tendency to increase as the cultivation years increases; the denitri- fication activity is relatively high, and increases significantly with the increase of culti- vation years.