氮磷营养盐对铜绿微囊藻和斜生栅藻生长及竞争的影响  

Effects of Nitrogen and Phosphorus on the Growth and Competition of Mcirocystis aeruginosa and Scenedesmus obliquus

作　　者：谢静[1] 程燕 查燕 汤婕[1] 束浩然 XIE Jing;CHEN Yan;ZHA Yan;TANG Jie;SHU Haoran(Auhui Agricultural University,Hefei 230036,China;Hefei Environmental Monitoring Center Station of Anhui Province,Hefei 230001,China;Hangzhou Academy of Agricultural Science,Hangzhou 310024,China)

机构地区：[1]安徽农业大学,安徽合肥230036 [2]安徽省合肥市环境监测中心站,安徽合肥230001 [3]杭州市农业科学研究院,浙江杭州310024

出　　处：《江西农业大学学报》2021年第3期694-702,共9页Acta Agriculturae Universitatis Jiangxiensis

基　　金：国家自然科学基金项目(51809001);安徽农业大学引进与稳定人才项目(wd2018-10)。

摘　　要：【目的】随着我国水体富营养化现象的日趋严重,由此产生的藻类水华问题已成为我国最为突出的环境问题之一,对水域环境和生态安全造成极大的危害,因此富营养化水体治理成为当务之急。研究选取优势蓝藻-铜绿微囊藻(Mcirocystis aeruginosa)和优势绿藻-斜生栅藻(Scenedesmus obliquus)为研究对象,分析不同氮磷比对藻类竞争生长的影响,以期为富营养化水体的水华研究及治理提供理论基础。【方法】通过室内模拟方法,以BG-11培养基为基础设置了5组氮磷比(N/P=1∶0,N/P=2.5∶1,N/P=5∶1 N/P=25∶1,N/P=50:1)的培养液,分别研究了不同氮磷比质量浓度对铜绿微囊藻和斜生栅藻生长及竞争的影响。【结果】(1)纯养模式下,铜绿微囊藻在低氮磷比(N/P=5:1)时生长适宜;斜生栅藻在高氮磷比(N/P=25∶1)下生长适宜;在氮质量浓度相同,不同氮磷比对两种藻类的最大生物量均具有显著影响(P<0.05),并随着磷浓度的升高,纯养和混养下两种藻类的最大生物量具有显著性差异。(2)通过比较纯养和混养发现,纯养模式下两种藻类的增长率都明显高于混养的增长率,说明两种藻类主要以资源利用性竞争为主,且铜绿微囊藻对于斜生栅藻的竞争抑制始终大于斜生栅藻对铜绿微囊藻的竞争抑制。(3)通过计算logistic生长方程可知,高氮磷比(N/P=50∶1)组在培养第20天,纯养模式下斜生栅藻的细胞密度值最大。(4)通过计算铜绿微囊藻对斜生栅藻的相对生长速率K_(R)值可知,除N/P=1∶0组之外,自培养第8天始其他4组的K_(R)值在1~2,说明铜绿微囊藻具有竞争优势。【结论】营养盐范围内,随着浓度增加会促进铜绿微囊藻和斜生栅藻的生长,但在高浓度范围内,两者生长反而受营养盐浓度增加的限制。氮磷元素对铜绿微囊藻和斜生栅藻的生长和竞争均有显著影响,两种藻类在纯养培养下的最大生物量显著大于混养培养,铜绿�[Objective]Recently,eutrophication and harmful algae blooms have become one of the most prominent environmental problems.As a result,aquatic environment and aquatic ecological safety have been greatly endangered.Therefore,eutrophic water treatment has become imperative.In this study,the dominant cyanobacteria-Microcystis aeruginosa and dominant green algae-Slagophyta-Scenedesmus Obliquus were selected as the research objects.The effects of different N/P ratios on the competitive growth,were analyzed so as to provide theoretical basis for water bloom control of eutrophic water.[Method]Under the laboratory conditions,five N/P ratio treating groups(N/P=1∶0,N/P=2.5∶1,N/P=5∶1 N/P=25∶1,N/P=50∶1)were set based on the BG-11 cultures to explore the different N/P ratios on the growth and competition of Mcirocystis aeruginosa and Scenedesmus obliquus by laboratory test.[Results](1)Under monoculture mode,Mcirocystis aeruginosa grew normally with N/P=5∶1,Scenedesmus obliquus grew normally with N/P=25∶1.At the same N mass concentration level,different ratios of N/P havd significant effect on the maximum biomass of the two kinds of algae(P<0.05).With the increase of phosphorus concentration,the maximum biomasses of pure and mixed algae were significantly different.(2)By comparing the pure culture test with the mixed culture test,it was found that the growth rates of the two kinds of algae under monoculture were significant higher than those under co-culture,which indicated that their interspecific competition was mainly in resource utilization.The competition inhibition of microcystis aeruginosa to Scenedesmus obliquus was always greater than that to Scenedesmus obliquus.(3)Calculating the logistic growth equation,it was found that the cell density was the highest under the monoculture mode in the group with high N/P ratio(N/P=50∶1)on the 20th day of culture.(4)By calculating the relative growth rate(K_(R))values Mcirocystis aeruginosa and Scenedesmus obliquus,except for N/P=1∶0,except for N/P=1∶0,the K_(R)

关 键 词：氮磷 铜绿微囊藻 斜生栅藻 生长 竞争 

分 类 号：X131.2[环境科学与工程—环境科学]