Adaptation by macrophytes to inorganic carbon down a river with naturally variable concentrations of CO2

Maberly, S.C.; Berthelot, S.A.; Stott, A.W.; Gontero, B.. 2015 Adaptation by macrophytes to inorganic carbon down a river with naturally variable concentrations of CO2. Journal of Plant Physiology, 172. 120-127.

Before downloading, please read NORA policies.
N508868PP.pdf - Accepted Version

Download (1MB) | Preview


The productivity and ecological distribution of freshwater plants can be controlled by the availability of inorganic carbon in water despite the existence of different mechanisms to ameliorate this, such as the ability to use bicarbonate. Here we took advantage of a short, natural gradient of CO2 concentration, against a background of very high and relatively constant concentration of bicarbonate, in a spring-fed river, to study the effect of variable concentration of CO2 on the ability of freshwater plants to use bicarbonate. Plants close to the source, where the concentration of CO2 was up to 24-times air equilibrium, were dominated by Berula erecta. pH-drift results and discrimination against 13C were consistent with this and the other species being restricted to CO2 and unable to use the high concentration of bicarbonate. There was some indication from stable 13C data that B. erecta may have had access to atmospheric CO2 at low water levels. In contrast, species downstream, where concentrations of CO2 were only about 5-times air-equilibrium were almost exclusively able to use bicarbonate, based on pH-drift results. Discrimination against 13C was also consistent with bicarbonate being the main source of inorganic carbon for photosynthesis in these species. There was, therefore, a transect downstream from the source of increasing ability to use bicarbonate that closely matched the decreasing concentration of CO2. This was produced largely by altered species composition, but partly by phenotypic changes in individual species.

Item Type: Publication - Article
Digital Object Identifier (DOI):
UKCEH and CEH Sections/Science Areas: Parr
ISSN: 0176-1617
Additional Keywords: bicarbonate, Fontaine de Vaucluse, photosynthesis, River Sorgue, stable carbon isotope
NORA Subject Terms: Ecology and Environment
Date made live: 26 Nov 2014 14:20 +0 (UTC)

Actions (login required)

View Item View Item

Document Downloads

Downloads for past 30 days

Downloads per month over past year

More statistics for this item...