In:
botm, Walter de Gruyter GmbH, Vol. 56, No. 1 ( 2013-02-01), p. 63-74
Abstract:
In natural environments, marine biotas are exposed to a variety of simultaneously acting abiotic factors. Among these, temperature, irradiance and CO 2 availability are major factors influencing the physiological performance of marine macroalgae. To test whether elevated levels of CO 2 may remediate the otherwise reduced performance of uncalcified seaweeds under the influence of other stressful abiotic factors, we performed multi-factorial experiments with the red alga Chondrus crispus from Helgoland (North Sea) with two levels of CO 2 , temperature and irradiance: low and high p CO 2 levels were tested in combination with either (1) optimal and low irradiances or (2) optimal and sub-lethal high temperatures for growth. Performance of C. crispus was evaluated as biomass increase and relative growth rates (RGR), gross photosynthesis and pigment content. Acclimations of growth and photosynthesis were measured after 4 and 8 days. Acclimation time was crucial for elucidating single or combined CO 2 effects on growth and photosynthesis. Significant CO 2 effects became evident only in combination with either elevated temperature or reduced irradiance. Growth and photosynthesis had divergent patterns: RGR and biomass significantly increased only under a combination of high p CO 2 and elevated temperature; gross photosynthesis was significantly reduced under high p CO 2 conditions at low irradiance. Pigment content varied in response to irradiance and temperature, but was independent of p CO 2 .
Type of Medium:
Online Resource
ISSN:
1437-4323
,
0006-8055
DOI:
10.1515/bot-2012-0143
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2013
detail.hit.zdb_id:
1475447-2
detail.hit.zdb_id:
1197-6
SSG:
12
