植物营养与肥料学报
植物營養與肥料學報
식물영양여비료학보
PLANT NUTRITION AND FERTILIZER SCIENCE
2013年
6期
1533-1538
,共6页
茶园土%不同氮肥处理%N2O排放%nosZ基因%定量PCR
茶園土%不同氮肥處理%N2O排放%nosZ基因%定量PCR
다완토%불동담비처리%N2O배방%nosZ기인%정량PCR
tea orchard soil%nitrogen fertilizer treatment%N2O emission%nosZ gene%quantitative PCR
茶园由于长期偏施氮肥，造成土壤酸化现象严重和N2 O大量排放。本文对强酸性茶园土壤进行不同氮肥处理试验，结果表明，通过31 d的好气培养，各施肥处理均显著提高N2 O排放，其中施硝酸钾（ KNO3）处理平均每天排放的N2O最高，总排放量为对照（CK）的17倍，其次是硝酸铵（NH4NO3）处理，尿素[CO（NH2）2]和硫酸铵[（NH4）2SO4]处理虽然能增加N2O排放，但远远小于硝酸钾处理。对各氮肥处理硝化势的测定表明，尿素、硫酸铵和硝酸铵处理均明显增加土壤硝化活性，而硝酸钾处理硝化势与对照相比显著降低。强酸性茶园土壤中N2 O排放的主要来源是反硝化作用。氧化亚氮还原酶（ nosZ）的定量PCR分析表明，硝酸钾处理的nosZ基因拷贝数与对照相比显著降低（ P＜0.05）。因此，强酸性土壤中N2 O还原酶活性被NO3-抑制是导致高N2 O排放的重要原因之一。
茶園由于長期偏施氮肥，造成土壤痠化現象嚴重和N2 O大量排放。本文對彊痠性茶園土壤進行不同氮肥處理試驗，結果錶明，通過31 d的好氣培養，各施肥處理均顯著提高N2 O排放，其中施硝痠鉀（ KNO3）處理平均每天排放的N2O最高，總排放量為對照（CK）的17倍，其次是硝痠銨（NH4NO3）處理，尿素[CO（NH2）2]和硫痠銨[（NH4）2SO4]處理雖然能增加N2O排放，但遠遠小于硝痠鉀處理。對各氮肥處理硝化勢的測定錶明，尿素、硫痠銨和硝痠銨處理均明顯增加土壤硝化活性，而硝痠鉀處理硝化勢與對照相比顯著降低。彊痠性茶園土壤中N2 O排放的主要來源是反硝化作用。氧化亞氮還原酶（ nosZ）的定量PCR分析錶明，硝痠鉀處理的nosZ基因拷貝數與對照相比顯著降低（ P＜0.05）。因此，彊痠性土壤中N2 O還原酶活性被NO3-抑製是導緻高N2 O排放的重要原因之一。
다완유우장기편시담비，조성토양산화현상엄중화N2 O대량배방。본문대강산성다완토양진행불동담비처리시험，결과표명，통과31 d적호기배양，각시비처리균현저제고N2 O배방，기중시초산갑（ KNO3）처리평균매천배방적N2O최고，총배방량위대조（CK）적17배，기차시초산안（NH4NO3）처리，뇨소[CO（NH2）2]화류산안[（NH4）2SO4]처리수연능증가N2O배방，단원원소우초산갑처리。대각담비처리초화세적측정표명，뇨소、류산안화초산안처리균명현증가토양초화활성，이초산갑처리초화세여대조상비현저강저。강산성다완토양중N2 O배방적주요래원시반초화작용。양화아담환원매（ nosZ）적정량PCR분석표명，초산갑처리적nosZ기인고패수여대조상비현저강저（ P＜0.05）。인차，강산성토양중N2 O환원매활성피NO3-억제시도치고N2 O배방적중요원인지일。
In recent years the long-term application of large amount of nitrogen fertilizers has led to the serious acidification of tea orchard soils with high N2O emission .In this study , different N fertilizers were applied to a highly acid tea orchard soil to evaluate the effects of N fertilizers on N2O emission.The results suggest that all the treatments increase N2O production significantly by the 31 days ’ aerobic incubation .The average N2O emission from the KNO3 treatment is the highest and total emission is 17 times higher than that of the control .The N2O emission of the NH 4 NO3 treatment is the next .The total N2O productions from the urea [ CO(NH2)2] and ( NH4 ) 2 SO4 treatments are stimulated but the N2O emissions are significantly lower than that of the KNO3 treatment.The Urea, (NH4)2SO4 and NH4NO3 treatments significantly stimulate soil nitrification activity, while the KNO3 treatment decreases nitrification potential .The results that denitrification is the dominant source of N2O emission in the highly acid tea orchard soil .To find out the microbial mechanism , quantitative PCR of the functional gene of nitrous oxide reductase ( nosZ) was determined.The results suggest that nosZ gene copies from the KNO3 treatment are significantly(P<0.05) lower than those of the control.Therefore, the inhibition of N2O reductase is one of the important factors to induce the high N2O emission in the highly acid soil .
