不同施肥方式对红壤蔬菜田氨氧化细菌和氨氧化古菌群落的影响

通过构建氨单加氧酶基因(amoA)克隆文库,研究在红壤蔬菜田上只施用磷钾化肥(PK)、只施氮磷钾化肥(NPK)、施用腐熟有机肥(DNPK)和施用新鲜有机肥(FNPK)等4种不同施肥处理的土壤氨氧化细菌(AOB)和氨氧化古菌(AOA)群落多样性及与土壤脲酶活性的相关性。结果表明:施加有机肥处理(DNPK和FNPK)的蔬菜田土壤的AOB文库和AOA文库OTU数量和Shannon指数高于只施用无机肥(NPK和PK)处理的蔬菜田土壤;DNPK和FNPK处理的土壤优势AOB菌群为多形亚硝化叶菌(Nitrosolobus multiformis),比例分别为88.5%和68.5%,NPK和PK处理的土壤优势AOB菌群为亚硝化单胞菌属(Nitrosospirasp.),比例分别为54.8%和65.5%;DNPK、FNPK、NPK和PK处理土壤优势AOA菌群均为阿伯丁土壤亚硝化细杆菌侯选种(CandidatusNitrosotalea devanaterra),比例分别为90.9%、84.4%、77.8%和45.2%;施加有机肥处理(DNPK和FNPK)的土壤脲酶活性和氨氧化微生物的多样性指数都高于只施用无机肥处理(NPK和PK);AOA群落多样性指数与土壤脲酶活性呈显著正相关,而AOB群落多样性与土壤脲酶活性相关性不显著。总体来看,有机肥比无机肥处理提高了AOA和AOB群落多样性,且AOA在红壤蔬菜田土壤氨氧化过程中起着更为重要的作用。

Effect of Different Fertilization on Ammonia-oxidizing bacteria and Ammoniaoxidizing archaea in Red Soil Vegetable Field

Adopting amoA gene clone library construction method，this paper studied the diversity of ammonia-oxidizing bacteria（AOB） and ammonia-oxidizing archaea（ AOA）and correlations between diversity index and urease activity in red soil vegetable field by different fertilization including decomposed organic fertilizer （DNPK），fresh organic fertilizer（FNPK），Nitrogen，Phosphorus and Potassium chemical fertilizer（NPK），Phosphorus and Potassium chemical fertilizer（PK）．The results showed that OTU quantity，Shannon index of AOB library and AOA library represented organic fertilizer（ DNPK and FNPK） were higher than that in chemical fertilizer soil（ NPK and PK）．The dominant AOB groups in FNPK and DNPK treated soil were Nitrosolobus multiformis，which represented 88.5% and 68.5%，respectively．The main AOB groups in chemical fertilizer soil（ NPK and PK） were Nitrosospira sp．with proportion of 54.8% and 65.5%，respectively．The main AOA groups in red earths were Candidatus Nitrosotalea devanaterra，which occupied 90.9% in DNPK treated soil，84.4% in FNPK treated soil，77.8% in NPK treated soil，and 45.2% in PK treated soil．The urease activity
and diversity index in soils treated by DNPK and FNPK were higher than that treated by NPK and PK．There was positive correlation between diversity index of AOA community and urease activity，but there was no marked positive correlation between diversity index of AOB community and urease activity．In conclusion，organic fertilizer was more able to improve the diversity of AOB and AOA communities in red soil of vegetable field than
chemical fertilizer．AOA community played more important role in the process of ammoxidation in red soil of vegetable field．