کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1722554 | 1014730 | 2010 | 6 صفحه PDF | دانلود رایگان |
Aquatic vegetation affects sediment suspension and nutrient release by changing the flow structure. Experiments on the influence of submerged vegetation on flow structure, sediment suspension, and NH4-N release were carried in a flume with natural submerged vegetation. Turbulence characteristics in the vegetation section were measured using a three-dimensional acoustic Doppler velocimeter. The effects of submerged vegetation on bed shear stress (τb), sediment suspension, and NH4-N release were analyzed. Results show that with vegetation, bed shear stress is reduced by about 20% – 80%, which, in turn, reduces sediment suspension. The impact of submerged vegetation on sediment suspension and NH4-N release should be considered along with flow intensity. When the flow Reynolds number is relatively small, the submerged vegetation is quite capable of inhibiting sediment suspension and reducing NH4-N release, but when the Reynolds number reaches a certain value, the presence of aquatic plants exacerbates sediment suspension and promotes NH4-N release. Results also reveal that a highly significant positive correlation exists between NH4-N concentration and water turbidity in both vegetated and non-vegetated channels.
Journal: Journal of Hydrodynamics, Ser. B - Volume 22, Issue 6, December 2010, Pages 810-815