水体富营养化对沉水植物与藻类生态关系的影响

【作者】 贺晓锋；

【导师】 苏文华；

【作者基本信息】 云南大学 ， 植物学， 2010， 硕士

【摘要】 水体富营养化是全球性环境问题,水生植物化感控藻方法在治理水体富营养化及水华现象中具有多方面的优势,近年来该领域的研究备受世界各国关注。以往的化感作用研究主要侧重于水生植物对藻的抑制作用,较少顾及到藻对水生植物的影响。藻类和水生植物生长在同一环境时,必定存在相互影响和竞争,所以对两者之间的相互化感作用进行研究,可以为防止水体富营养化和水化爆发提供更科学、全面的依据。在我国大部分富营养化水体中,铜绿微囊藻(Microcystis aeruginosa)的数量和爆发频率均占一定优势,而粉绿狐尾藻(Myriophyllum aquaticum)和穗状狐尾藻(Myriophyllum spicatum)是能够强烈抑制铜绿微囊藻生长的高等水生植物。本文通过对两种狐尾藻不同营养水平和光照强度处理,旨在弄清环境因子与其有效成分积累之间的关系;采用提取植物种植水初始添加法、连续添加法等方法,探讨了不同初始密度藻细胞、两种狐尾藻不同营养水平和光照强度处理、不同种植密度及不同组织部位等因素对其化感效应的影响;同时采用共培法,研究了不同藻细胞、不同藻类生物质对两种狐尾藻的化感效应影响。研究结果表明:1、光照和遮荫环境下,粉绿狐尾藻的Fo、Fv/Fm都随着营养浓度的升高而降低,但梯度间并没有显著差异,说明营养过剩并未对粉绿狐尾藻造成严重损害。2、富营养环境下,光照组和遮荫组两种狐尾藻的新增节数有明显差异,因此在富营养环境下,两种狐尾藻可以通过改变节数的密度来应对弱光环境。3、超富营养、富营养、贫营养三种营养水平下,两种狐尾藻的总黄酮含量都随着全N含量的升高而降低,结果符合C/N平衡假说。4、超富营养、富营养、贫营养三种营养水平下,两种狐尾藻遮荫组的抑藻效应均明显高于光照组,而营养梯度之间的抑藻效应差异不大,所以,遮荫条件下,植株释放了更多的化感物质,光照条件比营养盐对植株化感物质的释放影响更大。5、不同接种藻密度下,不同种植密度粉绿狐尾藻的抑藻效应无明显差异,但在20g/L到40g/L之间是抑藻效果更好。在藻液接种密度OD=0.4时,穗状狐尾藻种植密度大于等于20g/L才能产生强烈的抑藻效应,在藻液接种密度OD=0.8时,种植密度要大于等于40g/L才能产生强烈抑藻效应,因此,穗状狐尾藻种植密度和藻液接种密度比处于一个固定比值范围内就能保持较好的抑藻效应。6、低浓度(OD=0.2～OD=0.5)的铜绿微囊藻液可以对狐尾藻植株产生促进作用,随着培养液中藻密度的增加,促进作用就越弱。但在藻液密度OD=0.5时,粉绿狐尾藻的生长已经开始受到抑制。7、不同藻类生物质下穗状狐尾藻的长度增加均超过对照组,且鲜藻液>干燥藻液>击碎藻液。击碎藻液和干燥藻液下的穗状狐尾藻湿重呈现负增长,应该是藻液的遮光效应和化感效应共同作用的结果。更多还原

【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.更多还原