Inorganic carbon assimilation in the Isoetids, Isoetes lacustris L. and Lobelia dortmanna L.

Bibliographic Data

ID23401698
AuthorsK Richardson, Chrisanthi Avgerou (0000-0002-8814-453X), Claudio Ciborra, H GRIFFITHS, Frank Land, M L Reed, J A Raven, N M Griffiths
Year1984
Volume61
Issue1
Pages115-121
Publication date1984-01-01
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueOecologia (JOURNAL)
Journal identifiersISSN: 0029-8549 • E-ISSN: 1432-1939
PublisherSpringer Science and Business Media LLC (PUBLISHER)
DOI10.1007/bf00379096
OpenAlexW28311393
LanguageEN
Citations received15
References cited32

The inorganic carbon fixation patterns of Isoetes lacustris and Lobelia dortmanna from an oligotrophic Scottish loch have been examined by following titratable acidity changes in plant sap and light/dark 14 CO 2 incorporation by roots and shoots. The diurnal pattern of titratable acidity changes in I. lacustris suggests crassulacean acid metabolism (CAM) while the lack of any change in titratable acidity in L. dortmanna suggests C 3 metabolism. Of the carbon fixed by L. dortmanna, 99.9% was taken up through the roots and fixation occurred primarily during the day. In Isoetes, CO 2 was taken up by both roots and shoots and during both day and night. Regardless of the site of CO 2 uptake, fixation occurred only in the shoots of both plants. Analysis of carbon isotope ratios of plant organic material was used to further investigate the photosynthetic mechanisms of these Isoetids. Considering the absence of a nighttime peak in titratable acidity in L. dortmanna, the Δ 13 C (Δ=δ 13 C plant-δ 13 C source) value of the shoots of L. dortmanna (-14.2‰) is indicative of C 3 photosynthesis limited by the rate of CO 2 diffusion. The less negative Δ of I. lacustris (-6.0‰) is consistent with both dark acidification of CAM and CO 2 limited C 3 photosynthesis. This is in contrast to the terrestrial Isoetes durieui which is shown to have a Δ value which is similar to a terrestrial C 3 plant. The carbon fixation patterns of these Isoetids suggest that the CO 2 concentration in the loch may be growth limiting, and that root uptake and/or dark acidification are means of optimising CO 2 supply. However, in view of the relatively high levels of CO 2 in sediment and bulk water, it is suggested that low levels of nutrients may also limit growth in these plants.

Actor–network theory · Epistemology · Framing (construction) · Information system · Knowledge management · Phenomenon · Social science · Sociology · Computer Science · Engineering · Information Systems Theories and Implementation

Tools

Open DOISci-Hub