Effects of long-term fertilization on organic nitrogen fractions in aquic brown soil

• Published in: Ying yong sheng tai xue bao Vol. 28; no. 5; p. 1661
• Main Authors: Ren, Jin Feng, Zhou, Hua, Ma, Qiang, Xu, Yong Gang, Jiang, Chun Ming, Pan, Fei Fei, Yu, Wan Tai
• Format: Journal Article
• Language: Chinese
• Published: China 18.05.2017
• Subjects: aquic brown soil; long-term fertilization; soil organic nitrogen form
• ISSN: 1001-9332
• DOI: 10.13287/j.1001-9332.201705.006

The purpose of present research was to investigate how different fertilization regimes altered soil organic nitrogen fractions and their inter-annual dynamics based on a series of long-term experiment (initiated at 1990), including: CK (non-fertilization); M (recycled pig manure); NPK (chemical fertilizer NPK); NPK + M (recycled pig manure with chemical fertilizer NPK). The results showed that soil organic nitrogen components under the different fertilization treatments presented contrastive patterns from the establishment the experiments to 2015. Generally, acid hydrolysable organic nitrogen content increased year by year. The amino acid nitrogen content under CK and NPK treatments consistently declined, although amino acid nitrogen for M and NPK+M treatments showed a increasing trend. These phenomena were probably ascribed to the utilization of soil amino acids by microbes. From 1990 to 2015, NPK treatment substantially elevated the content of acid-released ammonium nitrogen by 31.1% compared with CK (mean