首页|期刊导航|中国海洋湖沼学报（英文版）|Photosynthetic efficiency, cell volume, and elemental stoichiometric ratios in Thalassirosira weissflogii under phosphorus limitation
中国海洋湖沼学报（英文版）2011，Vol.29Issue(5)：1048-1056,9.DOI:10.1007/s00343-011-0224-2
Photosynthetic efficiency, cell volume, and elemental stoichiometric ratios in Thalassirosira weissflogii under phosphorus limitation
Photosynthetic efficiency, cell volume, and elemental stoichiometric ratios in Thalassirosira weissflogii under phosphorus limitation
摘要
Abstract
Nutrient limitation is known to inhibit growth and metabolism and to alter elemental stoichiometric ratios in phytoplankton.In this study,physiological changes in Thalassirosira weissflogii were measured under different dissolved inorganic phosphate (DIP) regimes in semi-continuous cultures to revisit the utility of the Redfield ratio for assessing nutrient limitation.The results showed that cell size increased with decreasing DIP availability.In the P-depleted treatment (f/2-P) the cell size was 1.48 times larger than that in the P-limited (f/100) treatment and 2.67 times larger than that in the P-saturated treatment (f/2 and f/10).The fucoxanthin to chlorophyll a ratio (Fuco/chl a) was relatively stable (about 0.3) in P-saturated cultures and was 10 times higher than that in P-limited and P-depleted cultures.During the experimental period,the photosynthetic efficiency index,△F/Fm',was relatively stable at ～0.50 in the P-saturated cultures,but quickly declined with decreasing DIP availability.Although cellular P content showed a significant difference between the P-saturated culture (1.6 pg/cell) and the P-limited culture (0.7 pg/cell),the N/P ratio in T.weissflogii did not show a trend with DIP availability and fluctuated slightly around 25.Our results suggest that cell division in T.weissflogii is not strictly size-gated but is probably regulated by a biochemical,and hence,an elemental stoichiometric ratio threshold,and that deviation of the cellular N/P ratio from the Redfield ratio is not a reliable indicator of algal nutrient stress.关键词
phosphorus/diatom/physiological responses/PAM/elemental ratioKey words
phosphorus/diatom/physiological responses/PAM/elemental ratio引用本文复制引用
LIU Sheng,GUO Zhiling,LI Tao,HUANGHui,LIN Senjie..Photosynthetic efficiency, cell volume, and elemental stoichiometric ratios in Thalassirosira weissflogii under phosphorus limitation[J].中国海洋湖沼学报（英文版）,2011,29(5):1048-1056,9.基金项目
Supported by CAS for Key Topics in Innovation Engineering (No.KZCX2-YW-JS206),the CAS/SAFEA International Partnership Program for Creative Research Teams (No.KZCX2-YW-T001),the National Natural Science Foundation of China (Nos.41076096,40828006,U1033003),and Guangdong Natural Science Fund (No.2010B031900039) （No.KZCX2-YW-JS206）
