Arsenic Accumulation in a Paddy Field in Bangladesh: Seasonal Dynamics and Trends over a Three-Year Monitoring Period
Citations Over TimeTop 10% of 2010 papers
Abstract
Shallow groundwater, often rich in arsenic (As), is widely used for irrigation of dry season boro rice in Bangladesh. In the long term, this may lead to increasing As contents in rice paddy soils, which threatens rice yields, food quality, and human health. The objective of this study was to quantify gains and losses of soil As in a rice paddy field during irrigation and monsoon flooding over a three-year period. Samples were collected twice a year on a 3D-sampling grid to account for the spatially heterogeneous As distribution within the soil. Gains and losses of soil As in different depth segments were calculated using a mass-balance approach. Annual As input with irrigation water was estimated as 4.4 +/- 0.4 kg ha(-1) a(-1). Within the top 40 cm of soil, the mean As accumulation over three years amounted to 2.4 +/- 0.4 kg ha(-1) a(-1), implying that on average 2.0 kg ha(-1) a(-1) were lost from the soil. Seasonal changes of soil As showed that 1.05 to 2.1 kg ha(-1) a(-1) were lost during monsoon flooding. The remaining As-loss (up to 0.95 kg ha(-1) a(-1)) was attributed to downward flow with percolating irrigation water. Despite these losses, we estimate that total As within the top 40 cm of soil at our field site would further increase by a factor of 1.5 to 2 by the year 2050 under current cultivation practices.
Related Papers
- → Methane and nitrous oxide emissions from paddy field as affected by water-saving irrigation(2011)127 cited
- → An analysis of groundwater irrigation expansion in India(2012)17 cited
- → Impacts of off-farm employment on groundwater irrigation in North China(2018)13 cited
- → Irrigation and Culm Contribution to Yield and Yield Components of Winter Wheat(1994)48 cited
- → Influence of Irrigation on the Yield and Persistence of Forage Legumes1(1972)10 cited