In Situ Dissimilatory Nitrate Reduction to Ammonium in a Paddy Soil Fertilized with Liquid Cattle Waste
详细信息查看全文 | 推荐本文 |
摘要
Most studies on dissimilatory nitrate reduction to ammonium (DNRA) in paddy soils were conducted in the laboratory and in situ studies are in need for better understanding of the DNRA process. In this study, in situ incubations of soil DNRA using 15N tracer were carried out in paddy fields under conventional water (CW) and low water (LW) managements to explore the potential of soil DNRA after liquid cattle waste (LCW) application and to investigate the impacts of soil redox potential (Eh) and labile carbon on DNRA. DNRA rates ranged from 3.06 to 10.40 mg N kg鈭? dry soil d鈭?, which accounted for 8.55%-12.36%and 3.88%-25.44%of consumption of added NO3鈭?/sub>15N when Eh at 5 cm soil depth ranged from 230 to 414 mV and 鈭?25 to 鈭?5 mV, respectively. DNRA rates showed no significant difference in paddy soils under two water managements although soil Eh and/or dissolved organic carbon (DOC) were more favorable for DNRA in the paddy soil under CW management 1 d before, or 5 and 7 d after LCW application. Soil DNRA rates were negatively correlated with soil Eh (P < 0.05, n = 5) but positively correlated with soil DOC (P < 0.05, n = 5) in the paddy soil under LW management, while no significant correlations were shown in the paddy soil under CW management. The potential of DNRA measured in situ was consistent with previous laboratory studies; and the controlling factors of DNRA in paddy soils might be different under different water managements, probably due to the presence of different microfloras of DNRA.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700