Research Repository

A key marine diazotroph in a changing ocean: The interacting effects of temperature, Co<inf>2</inf> and light on the growth of trichodesmium erythraeum IMS101

Boatman, TG and Lawson, T and Geider, RJ (2017) 'A key marine diazotroph in a changing ocean: The interacting effects of temperature, Co<inf>2</inf> and light on the growth of trichodesmium erythraeum IMS101.' PLoS ONE, 12 (1). ISSN 1932-6203

[img]
Preview
Text
journal.pone.0168796.pdf - Published Version
Available under License Creative Commons Attribution.

Download (3MB) | Preview

Abstract

© 2017 Boatman et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Trichodesmium is a globally important marine diazotroph that accounts for approximately 60-80% of marine biological N2 fixation and as such plays a key role in marine N and C cycles. We undertook a comprehensive assessment of how the growth rate of Trichodesmium erythraeum IMS101 was directly affected by the combined interactions of temperature, pCO2 and light intensity. Our key findings were: low pCO2 affected the lower temperature tolerance limit (Tmin) but had no effect on the optimum temperature (Topt) at which growth was maximal or the maximum temperature tolerance limit (Tmax); low pCO2 had a greater effect on the thermal niche width than low-light; the effect of pCO2 on growth rate was more pronounced at suboptimal temperatures than at supraoptimal temperatures; temperature and light had a stronger effect on the photosynthetic efficiency (Fv/Fm) than did CO2; and at Topt, the maximum growth rate increased with increasing CO2, but the initial slope of the growth-irradiance curve was not affected by CO2. In the context of environmental change, our results suggest that the (i) nutrient replete growth rate of Trichodesmium IMS101 would have been severely limited by low pCO2 at the last glacial maximum (LGM), (ii) future increases in pCO2 will increase growth rates in areas where temperature ranges between Tmin to Topt, but will have negligible effect at temperatures between Topt and Tmax, (iii) areal increase of warm surface waters (> 18°C) has allowed the geographic range to increase significantly from the LGM to present and that the range will continue to expand to higher latitudes with continued warming, but (iv) continued global warming may exclude Trichodesmium spp. from some tropical regions by 2100 where temperature exceeds Topt.

Item Type: Article
Subjects: Q Science > QH Natural history > QH301 Biology
Depositing User: Richard Geider
Date Deposited: 18 Jan 2017 09:46
Last Modified: 01 Aug 2019 13:20
URI: http://repository.essex.ac.uk/id/eprint/18818

Actions (login required)

View Item View Item