In:
Advanced Materials Research, Trans Tech Publications, Ltd., Vol. 599 ( 2012-11), p. 820-826
Abstract:
In this experiment, we simulated the migration and transformation law of nitrate under the condition of water table rise caused by rainfall in Changping District of Beijing. Two types of experimental apparatus were used in the experiment to simulate the distribution of NO3--N, NO2--N and NH4+-N, which were named soil column 1 and soil column 2. Soil column 2 was under the condition of rainfall and soil column 1 was for comparison. It took 50.3 hours for the experiment during which simples were taken and tested. The test items were the concentration of NO3--N, NO2--N and NH4+-N. The results indicated that (1) In unsaturated zone, the influence of leaching caused by rainfall on the concentrations of NO3--N and NH4+-N were significant. The decreasing range could reach to 95.9% and 90% which means that it was easily to lead to the contamination of groundwater. In saturated zone, NO3--N concentrations were mainly influenced by dispersion and could achieve balance between the dilution and dispersion with the increase of rainfall. The increasing range of NO3--N concentration was large, and the value could reach to 675%. In addition, the NH4+-N concentration had a slight trend of decrease. (2) Under the condition of rainfall, NO3--N concentrations increased in saturated zone, decreased in the path of water table rise and unsaturated zone. The NH4+-N concentrations had a decreasing trend in saturated-unsaturated zone. (3) NH4+-N concentrations in medium sand were more easily influenced by leaching from rainfall than those in silt.
Type of Medium:
Online Resource
ISSN:
1662-8985
DOI:
10.4028/www.scientific.net/AMR.599
DOI:
10.4028/www.scientific.net/AMR.599.820
Language:
Unknown
Publisher:
Trans Tech Publications, Ltd.
Publication Date:
2012
detail.hit.zdb_id:
2265002-7
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