Pedosphere 9(3): 281--288, 1999
ISSN 1002-0160/CN 32-1315/P
©1999 Soil Science Society of China
Published by Elsevier B.V. and Science Press
| Effect of irradiated sewage sludge on crop yield and soil nitrogen |
| XU Yang-Chun, JIANG Ting-Hui, ZHENG Shao-Jian and ZHOU Li-Xiang |
| Nanjing Agricultural Univereity, Nanjing 210095 (China) |
| ABSTRACT |
| A field experiment was conducted to study the feasibility of irradiated and non-irradiated sewage sludge as a fertilizer for the growth of wheat and rice. The irradiated and non-irradiated sewage sludge were applied at rates of 0 (CK), 75, 150, 225 and 300 kg N ha-1 for wheat, and 0 (CK), 112.5, 225, 337.5 and 450 kg N ha-1 for rice, respectively. (NH4)2SO4 at a rate of 150 kg N ha-1 for wheat, and 225 kg N ha-1 for rice were added to the control treatments. Additionally, 20 kg 15N ha-1 in the form of (NH4)2SO4 was added to each treatment for wheat to study the effect of sewage sludge on chemical nitrogen fertilizer recovery. The results showed that the irradiation of sewage sludge by gamma ray at a dosage of 5 kGy increased crop yield by 11%~27% as compared to the non-irradiated treatments. Irradiation stimulated mineralization of organic nitrogen in the sludge and improved seedling growth. It was found that addition of irradiated sludge could reduce the leaching loss of chemical nitrogen fertilizer. Both irradiated and non-irradiated sewage sludge could increase the content of soil total nitrogen. Based on the preliminary results, it was concluded that irradiated sewage sludge could partly substitute for chemical nitrogen fertilizer in crop production. |
| Key Words: crop yield, irradiation, sewage sludge, soil nitrogen |
| Citation: Xu, Y. C., Jiang, T. H., Zheng, S. J. and Zhou, L. X. 1999. Effect of irradiated sewage sludge on crop yield and soil nitrogen. Pedosphere. 9(3): 281-288. |
| |
|
View Full Text
|
|
|
|
