摘要
以龙须菜和蛎菜两种大型海藻为试验材料,在室外自然条件下培养,设置常规CO2浓度(390μL·L-1)和高CO2浓度(800μL·L-1)空气两种通气条件、以及10和150μmol·L-1两种氮营养盐供应水平,以探讨大气CO2浓度升高对不同氮营养盐生长条件下海藻生长与光合特性的影响。结果表明:不管是高氮还是低氮的培养条件,大气CO2浓度升高都能促进这两种海藻的生长;在龙须菜中,这种生长促进作用在低氮培养条件下更高,而在蛎菜中这种生长促进作用在高氮培养条件下较高;短期海水中高CO2浓度能促进蛎菜和龙须菜的光合作用;长期高CO2浓度生长环境依然能维持龙须菜高的光合作用,但抑制蛎菜的光合作用。另外,不管培养液中CO2供应条件如何,氮加富均促进了龙须菜和蛎菜这两种海藻的光全和呼吸作用。
This study adopted two species of marine macroalgae,Gracilaria lemaneiformis and Ulva conglobata as experimental materials,which were cultured under outdoor conditions. The treatments were designated as ambient（ 390 μL·L^- 1） and elevated（ 800 μL·L^- 1） CO2concentrations,and low（ 10 μmol·L^- 1） and high N（ 150 μmol·L- 1） availability,in order to examine the effects of elevated CO2on growth and photosynthesis in marine macroalgae grown at different N supplies. During the cultivation,the biomass of the algae was measured. After culture for 18 days,the photosynthesis was examined with seawater in equilibrium with ambient（ 390 μL·L^- 1） air and CO2-enriched（ 800 μL·L^- 1） air,respectively. The results showed that elevated CO2significantly enhanced the relative growth rate（ RGR） in both the macroalgal species regardless of the N levels in culture. However,the enhancement of growth was more pronounced in G. lemaneiformis,but less pronounced in U. conglobata,under low than high N conditions.Short-term exposure to CO2enrichment stimulated photosynthesis of both the macroalgal species.Such stimulation of photosynthesis in G. lemaneiformis could be fully remained with prolonged growth with enriched-CO2. However,long-term growth condition of CO2enrichment had an inhibitory effect on photosynthesis in U. conglobata. Additionally,the enriched N supply significantly increased photosynthesis and respiration in both the macroalgal species,regardless of the CO2concentration in culture.
出处
《生态学杂志》
CAS
CSCD
北大核心
2014年第6期1520-1527,共8页
Chinese Journal of Ecology
基金
国家自然科学基金项目(41076094和41276148)资助
关键词
CO2
氮
蛎菜
龙须菜
生长
光合作用
CO2
nitrogen
Ulva conglobata
Gracilaria lemaneiformis
growth
photosynthesis.
