[1]Experimental Study on Nitrate Nitrogen Migration in Soils Along the River Under Interaction of Surface Water and Groundwater[J].Research of Soil and Water Conservation,2021,28(02):67-73.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
28
Number of periods:
2021 02
Page number:
67-73
Column:
Public date:
2021-02-06
- Title:
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Experimental Study on Nitrate Nitrogen Migration in Soils Along the River Under Interaction of Surface Water and Groundwater
- Author(s):
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(School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, Shandong 266000, China)
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- Keywords:
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surface water-groundwater interaction; soil; nitrate nitrogen; migration law
- CLC:
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X523
- DOI:
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- Abstract:
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This research aimed to study the migration pattern of nitrate nitrogen in farmland next to rivers under different recharge relations between surface water and groundwater. Sand samples from riverbeds at different locations on the Dagu River were used as sand tank experimental media. Surface water and groundwater complementary feeding devices were designed to simulate leaching of nitrate nitrogen in the soil in three ways: no recharge, surface water recharge, and groundwater recharge, migration of nitrate nitrogen was determined by measuring the nitrate nitrogen content and the arrival time at each sampling point. The results show that: in the pure leaching experiment, the smaller the leaching intensity and sand-like particles, the more obvious the accumulation of nitrate nitrogen in the surface sand, and the slower the migration of nitrate nitrogen; in the experiment of supplementary surface water and groundwater, the supply water level increased, the accumulation of nitrate nitrogen increased, and the time of nitrate migration to the saturated zone was shortened; when the supply hydraulic gradient is 0.5, the speed of nitrate nitrogen migrates in the fine sand saturated zone is about 5.3 cm/min; when the hydraulic gradient becomes 0.7, the speed of nitrate migration is about 9.4 cm/min; when the recharge hydraulic gradient is 0.5, the nitrate nitrogen migration speed is about 12.3 cm/min. The accumulation of nitrate nitrogen in the unsaturated zone decreases with the increase of the sand depth. The greater the leaching intensity, hydraulic slope and sand-like particles, the faster the migration speed of nitrate nitrogen in the unsaturated zone and saturated zone; the higher the recharge water level, the shorter the time for nitrate nitrogen to migrate to the saturated zone.