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Full Length Research Paper
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The effect of
hydrodynamics on nitrogen accumulation and physiological
characteristics of
Vallisneria
spiraslis
L
in eutrophicated water
Pei-Fang Wang1,3, Chao Wang2, Xiao-rong
Wang1*, Jun Hou2 and Song-He Zhang2
1State
Key Laboratory of Pollution Control and Resource Reuse,
School of the Environment, Nanjing University, Nanjing
210093, China.
2Key
Laboratory of Intergrated Regulation and Resource
Development on Shallow Lakes of Ministry of Education,
College of Environmental Science and Engineering, Hohai
University, Nanjing 210098, China.
3State
Key Laboratory of Hydrology-Water Resources and Hydraulic
Engineering, Nanjing, 210098, China.
*Corresponding
author. E-mail:
ekxr@nju.edu.cn. Tel: +86-(25)-83786696.
Accepted
6 June, 2008 |
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Abstract |
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Natural water hydrodynamic conditions play an important role
in the nutrients transport among water, soil and plants.
Meanwhile, aquatic plants affect the water flow characters
and pollutants purification capability. However, there are
limited studies on how these conditions affects the nutrient
uptake and physiological response of aquatic plants. From
May 18 to June 28, 2007, a kind of submerged plant,
Vallisneria spiraslis L, was selected to observe the
difference in nitrogen accumulation and antioxidant system
and their changes in both shoots and roots of the plant
between hydrodynamic condition (D flume) and relative
hydrostatic condition (S flume). The results showed that
under hydrodynamic conditions, the nitrogen accumulation in
shoots increased rapidly, and maintained a higher level of
nitrogen accumulation than that of the hydrostatic flume.
Furthermore, in the initial stage of the experiment, the
total chlorophyll of V. spiraslis in the D flume
decreased because of the hydrodynamic stress inhibition,
while Chl a and b appeared to be a little synthesized in the
S flume. Moreover, rapid induction in antioxidant enzyme
activity occurred in shoots of the plant in the D flume, and
the activity levels of POD and GSH were significantly higher
than those of the S flume.
Key
words:
running water,
Vallisneria
spiraslis
L,
nitrogen accumulation, chlorophyll, antioxidant defense. |
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