Nitrogen loss and its health risk in paddy fields under different drainage managements |
| |
Authors: | Abdullah Darzi-Naftchali Ali Shahnazari Fatemeh Karandish |
| |
Affiliation: | 1.Water Engineering Department,Sari Agricultural Sciences and Natural Resources University,Sari,Iran;2.Water Engineering Department,Zabol University,Zabol,Iran |
| |
Abstract: | Subsurface drainage is a prerequisite for year-round crop production in a large area of northern Iran, s paddy fields. Minimizing environmental and health issues related to nitrogen (N) losses through subsurface drainage systems provides suitable condition for sustainable agriculture in these fields. A field study was conducted to evaluate nitrogen loss and its health risk in the conventional and subsurface-drained paddy fields. Ammonium, nitrate, and total N concentrations of subsurface drainage effluents, surface runoff, and leachates were monitored during three successive rice-canola-rice growing seasons from July 2011 to August 2012. Different components of N balance and health risk of nitrate leaching to groundwater were also investigated. Ammonium in drainage effluents collected during the experimental period ranged from approximately zero to 1.72 mg L?1, while nitrate fluctuated from 0.5 to 28.6 mg L?1. Average nitrate concentration in leachates of subsurface-drained area was 7.7–81.4 % higher than that in subsurface drainage effluents, while it was 126.8 % higher than that in surface runoff for the conventional field. Subsurface drainage provided a better utilization of soil N through providing winter cropping and reduced the potential for non-carcinogenic risks of nitrate leaching to groundwater. The results are encouraging for producers engaged in rice-canola production in the study area with respect to the environment and human health quality. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|