Nitrogen retention capacity of paddy soil improved under long-term garlic-rice rotation

ABSTRACT

Although significant differences in soil nitrogen levels exist under different paddy-upland rotations, the main reason for this is unclear. The nitrogen retention capacity and loss of ammonia volatilisation, leaching, etc. of paddy soil with large differences in nitrogen levels from two long-term rotations, garlic-rice and wheat-rice, were measured using the soil column simulation method. The results showed that the loss rate of leaching was only 5.4%, whereas that of ammonia volatilisation was up to 22.8%, which was the main nitrogen loss way of paddy soil under the two rotations. The average ammonia volatilisation rates under wheat-rice rotation with high and low nitrogen application rates were 12.1% and 40.2% higher than that under garlic-rice rotation, leading to a decrease in the total nitrogen loss amount and rate through ammonia volatilisation by 29.8% and 8.8%, respectively. As a result, nitrogen retention in the soil under garlic-rice rotation increased by 12.7%. In conclusion, the long-term garlic-rice rotation could significantly inhibit ammonia volatilisation, thus improving the soil nitrogen retention capacity. The straw return may increase soil organic matter content, reduce ammonia volatilisation loss, and enhance soil nitrogen retention capacity and productivity.

KEYWORDS:

• Ammonia volatilisation
• leaching
• long-term experiment
• soil nitrogen level
• wheat-rice cropping system

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Natural Science Foundation of Sichuan Province [grant number 2022NSFSC1637], and National College Students Innovation and Entrepreneurship Training Program [grant number S202210626063].

Notes on contributors

Wei Zhou

Wei Zhou holds a doctorate in Agriculture majoring in Crop Cultivation and Farming System, with more than 10 years of Research Experience in nitrogen utilization of Paddy-upland rotation.

Yanqiu Chen

Yanqiu Chen, Zhitao Hu, and Yihong Kuang, are Undergraduate majoring in agriculture, and interested in soil nitrient cycling.

Yu Fan

Yu Fan is Graduate student majoring in Crop Cultivation and Farming System, He has research interests in efficient and safe production of rice.

Tao Wang

Tao Wang is a postdoctor majoring in Crop Cultivation and Farming System, is devoted to the study of green production and emission reduction of rice-base cropping system.

Yong Chen

Youfeng Tao and Hong Cheng engaged in rice field production and experimental management.

Fei Deng

Yong Chen, Fei Deng, and Xiaolong Lei, are Associate Professor, are devoted to the study of green, efficient, high quality, high yield and mechanized production of rice-base cropping system.

Jianfeng Hu

Jianfeng Hu holds a doctorate in Agriculture majoring in Crop Cultivation and Farming System, is a assistant dean of Sichuan Agricultural University, and committed to rural revitalization.

Wanjun Ren

Wanjun Ren is a Professor and division chief of Sichuan Agricultural University, with more than 10 years of Research Experience in the green, efficient, high quality, high yield and mechanized production of rice.