The growth and photosynthesis traits of Scendesmus obliquus exposed to the culture medium ( SE medium) with different concentrations of salinity (5, 10, 15, 20, 25) and carbonate alkalinity (5, 10, 15, 20, 25, 30, 35 mmol/L) for different periods (1 -7 d) were studied. Results showed that the parameters, including cell density and chlorophyll a content decreased significantly ( P < 0. 05) with the increase of salinity and the prolongation of time in high salinity treatments (15, 20, 25). The photosynthetic rate showed the similar changing trend, but when the salinity was relatively low (5, 10) , the tendency was not significant (P>0. 05). Therefore, the high salinity (15 -25) inhibited the growth and photosynthetic rate of Scendesmus obliquus severely, but the low salinity (5-10) did not affect Scendesmus obliquus significantly. In alkali-stress, results showed that cell density, chlorophyll a content and photosynthesis rate all increased significantly compared to the control group, in which all parameters ( cell density, chlorophyll a content and photosynthesis rate) had the highest value when the carbonate alkalinity was 5 mmol/L. These results indicated that carbonate alkalinity was conducive to the growth of Scendesmus obliquus.%在不同盐度(5,10,15,20,25)和碳酸盐碱度(5,10,15,20,25,30,35 mmol/L)胁迫下,研究了胁迫后(1～7d内)斜生栅藻(Scenedesmus obliqnus)的生长及光合特性.结果表明:高盐度胁迫(15,20,25)对斜生栅藻有显著的胁迫抑制作用,低盐度胁迫(5 ～10)对其影响不明显.在15,20,25高盐度环境中,随着胁迫时间增加斜生栅藻的细胞密度(A680nm)、叶绿素a含量和光合速率数值下降幅度显著,胁迫7d后较对照组分别下降了30.2％～ 59.7％、16.8％～ 57.1％和40.2％ ～91.5％；低盐度(5,10)环境中斜生栅藻的细胞密度、叶绿素a含量、光合速率与对照组差异不显著.一定浓度的碳酸盐碱度对斜生栅藻生长具有显著的促进作用.在高碳酸盐碱度(5～35 mmol/L)环境中,随着胁迫时间增加斜生栅藻的细胞密度、叶绿素a含量和光合速率数值上升幅度显著,其中在碳酸盐碱度为5 mmol/L的环境中各参数上升幅度最高,胁迫7d后细胞密度、叶绿素a含量和光合速率分别较对照组升高了307.0％、328.9％和150.2％.
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