Sample Paper_Submission.pdf

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allelochemicals of Phragmites communis reduced the activities of superoxide dismutase (SOD) and
peroxidase (POD), to decline the ability to remove reactive oxygen species, and disorder the cell redox
state, to cause cell death[45]. The exudates of Eichhornia crassipes stressed the SOD activity of
Scenedesmus from initial increase to gradual decrease, but increased POD activity all through[48].
4 Possible application ways for algal-bloom control using allelopathy
The potential ways for utilizing allelochemicals of aquatic macrophytes contain transplanting live plants,
delivering harvested and dried plants, extracting allelochemicals from plants and synthesizing
allelochemicals with natural structures.
Transplanting live plants is suitable for small water bodies like landscape ponds. It can satisfy the
requirement of algae inhibition and beautify the environment. The management of aquatic plants is also
easy because of the small area. However, transplanting live plants costs a lot of time and labor and the
plants are affected easily and greatly by season change. The method is effective slow and timely poor. So
the plants may not be able to suffer from algal bloom. On the other hand it is not suitable for large water
area because the plants may reproduce excessively.
In the decay process, the plants may release allelochemicals and provide habitat places for fish, shrimp,
and aquatic organisms. However, this method spoils the beauty of environment. And the release of
nutrients in the process could cause the secondary pollution and trigger other environmental problems.
Extracting allelochemicals from plants and applying them into water bodies is a promising method
because of its easy control and quick effect. Allelochemicals from macrophytes are natural algicides. Rice
claimed that allelochemicals might replace the man-made herbicides, at least could greatly reduce the
amount of herbicide usage[27]. Therefore, extraction, separation, identification and synthesis of
allelochemicals can provide new algicides for algal-bloom control. Combination with other recycle
methods, such as papermaking, methane fermentation system, etc can solve the problem of residue
disposal.
Synthetic allelochemicals can make up biomass shortage of aquatic plants. And the efficiency of
synthetic allelochemicals can be improved during the synthesizing procedure to satisfy the requirement of
algal-bloom control. Therefore, the synthetic method will become a future development direction.
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