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Eutrophication of submerged plants and algae in the ecological relationships

Author: HeXiaoFeng
Tutor: SuWenHua
School: Yunnan University
Course: Botany
Keywords: eutrophication Microcystis aeruginosa Myriophyllum aquaticum Myriophyllum spicatum Allelopathic inhibition effects flavonoid
CLC: X52
Type: Master's thesis
Year: 2010
Downloads: 153
Quote: 1
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Abstract

The water eutrophication is a global environmental problems,the aquatic vegetalization feeling controls the algae method to govern in the water eutrophication and the water bloom phenomenon has various superiority, so this area of research by the world’s attention in recent years. The former allelopathic effects research mainly stresses on the aquatic plant to algae’s inhibitory action, little takes into consideration to the algae to aquatic plant’s influence. The algae and the aquatic plant grow when the identical environment, has the mutual influence and the competition surely, therefore melts the allelopathic effects to both between to conduct the research mutually, may to prevent the water body eutrophication and the hydrated eruption provides scientifically, the comprehensive basis. Most of the water body eutrophication in our country, Microcystis aeruginosa`s quantity and the eruption frequency occupy certain superiority, but the water plant of a higher level like Myriophyllum aquaticum and the Myriophyllum spicatum is able to hold a strong growth. In this article through compare Myriophyllum aquaticum and Myriophyllum spicatum with different nutritional level and strength of illumination processing, is for the purpose of clarifying the environment factor to accumulate with its effective component the relations. Uses the extraction plant planter water initial increase law, the company to add methods and so on addition, has discussed different initial density factors and so on algae cell, two kind of aquatic plants different nutritional level and strength of illumination processing, different planting density and different organization spot melts the allelopathic effects to it the influence; Simultaneously uses the altogether cultivates method, studied the different algae cell, the different algae biology to confront two kind of Myriophyllum aquaticum the feeling effect influence. The findings indicated:1. The illumination and provides shade under the environment, Myriophyllum aquaticum’s Fo, Fv/Fm elevate along with the nutrition density reduce, but between the gradient the remarkable difference, had not shown that the excess nutrient has not created the serious damage to the powder green Myriophyllum aquaticum.2. Under the rich nutrition environment, the illumination group and provides shade the group Myriophyllum aquaticum and Myriophyllum spicatum additional pitch numbers to have the obvious difference, therefore under the rich nutrition environment, two kind of aquatic plants may deal with the weak light environment through the change pitch number density.3. In the ultra rich nutrition, the rich nutrition, under the poor nutrition three nutritional levels, Myriophyllum spicatum and Myriophyllum aquaticum’s total flavanone content elevate along with the entire N content reduce, finally conforms to the C/N balanced hypothesis.4. In the ultra rich nutrition, the rich nutrition and under the poor nutrition three nutritional levels, Myriophyllum spicatum and Myriophyllum aquaticum provide shade the group to damp the algae effect obviously to be higher than the illumination group, but between the nutrition gradient of the allelopathic inhibition effects difference not to be big, therefore, provides shade under the condition, the adult plant released the more allelochemicals, the illumination condition has affected the nutrient salt to the adult plant feeling material release is more bigger.5. Under the different vaccination algae density, the different planting density powder green Myriophyllum aquaticum damps the algae effect not obvious difference, but is damps the algae effect in 20g/L to 40g/L between to be better. When algae fluid vaccination density OD=0.4, the fringy Myriophyllum spicatum planting density is bigger than was equal to that 20g/L can produce intensely damps the algae effect, when algae fluid vaccination density OD=0.8, the planting density must be bigger than was equal to that 40g/L can produce damps the algae effect intensely, therefore, the fringy Myriophyllum spicatum planting density and the algae fluid vaccination density compared to is in a fixed ratio scope to be able to maintain good damps the allelopathic inhibition effects.6. In the low concentration (OD=0.2~OD=0.5) the verdigris Microcystis aeruginosa fluid may have the promoter action to the Myriophyllum spicatum and Myriophyllum aquaticum Along with the nutrient fluid in algae density’s increase, the promoter action is weaker. But when Microcystis aeruginosa fluid density OD=0.5, the Myriophyllum aquaticum’s growth already started to receive suppresses.7. The different algae biomass under the material the fringy Myriophyllum spicatum length is surpass increase to the control group, and the fresh algae fluid > the dry algae fluid > crushes the algae fluid. Under the crushing algae fluid and the dry algae fluid’s fringy Myriophyllum spicatum wet weight presents the negative growth, should be the algae fluid shade effect and the feeling effect combined action result.

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CLC: > Environmental science, safety science > Environmental pollution and its prevention > Water pollution and its control
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