TY - JOUR
T1 - The influence of incubation periods on photosynthesis-irradiance curves
AU - Ferreira, João Pedro Salgueiro Gomes
AU - Duarte, Pedro M.
AU - Macedo, Maria Filomena
N1 - Funding Information:
This work was supported by Fundação para a Ciência e Tecnologia (Project JNICT/MAR/2245/95—Development of a Model for Coastal Lagoon Management) and PhD grant BD/4146/96. The authors would like to thank to Dr. G. Calado for the help given during sampling. Helpful comments from the anonymous reviewer of the manuscript are also acknowledged. [RW]
PY - 2002/8/5
Y1 - 2002/8/5
N2 - In phytoplankton primary production studies, samples for the determination of photosynthesis versus irradiance relationship (P-I) are usually incubated at several irradiance levels during a fixed time period, commonly 2-4 h. However, it is not clear if the use of this fixed incubation time is appropriate to study the P-I relationship in any given ecosystem. The aim of this work was to study the influence of incubation time on the P-I relationship in natural phytoplankton populations from three different coastal ecosystems: an open coastal area, an estuary, and a coastal lagoon. Physical and chemical variables, phytoplankton biomass, species composition, and P-I curves were analysed. The results showed that, in the coastal area and in the estuary, P-I relationships were time dependent, whereas in the coastal lagoon different incubation periods produced the same P-I curve. An underestimation of daily primary production, ranging from 13% to 42.5%, was calculated when data from standard incubation times (2-4 h) were used in ecosystems where P-I curves present a dynamic time-dependent behaviour. This work suggests that the response of the P-I curves to the incubation time varies with the characteristics of the ecosystem and is related to the light regime to which phytoplankton cells are adapted.
AB - In phytoplankton primary production studies, samples for the determination of photosynthesis versus irradiance relationship (P-I) are usually incubated at several irradiance levels during a fixed time period, commonly 2-4 h. However, it is not clear if the use of this fixed incubation time is appropriate to study the P-I relationship in any given ecosystem. The aim of this work was to study the influence of incubation time on the P-I relationship in natural phytoplankton populations from three different coastal ecosystems: an open coastal area, an estuary, and a coastal lagoon. Physical and chemical variables, phytoplankton biomass, species composition, and P-I curves were analysed. The results showed that, in the coastal area and in the estuary, P-I relationships were time dependent, whereas in the coastal lagoon different incubation periods produced the same P-I curve. An underestimation of daily primary production, ranging from 13% to 42.5%, was calculated when data from standard incubation times (2-4 h) were used in ecosystems where P-I curves present a dynamic time-dependent behaviour. This work suggests that the response of the P-I curves to the incubation time varies with the characteristics of the ecosystem and is related to the light regime to which phytoplankton cells are adapted.
KW - Incubation periods
KW - Modelling
KW - Photoinhibition
KW - Phytoplankton productivity
UR - http://www.scopus.com/inward/record.url?scp=0037025863&partnerID=8YFLogxK
U2 - 10.1016/S0022-0981(02)00202-2
DO - 10.1016/S0022-0981(02)00202-2
M3 - Article
SN - 0022-0981
VL - 274
SP - 101
EP - 120
JO - Journal Of Experimental Marine Biology And Ecology
JF - Journal Of Experimental Marine Biology And Ecology
IS - 2
ER -