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Your search keyword '"Duarte, Carlos M."' showing total 25 results
Start Over Author "Duarte, Carlos M." Journal aquatic botany
25 results on '"Duarte, Carlos M."'

24. Light availability and temperature, not increased CO2, will structure future meadows of Posidonia oceanica.

Author

Hendriks, Iris E., Olsen, Ylva S., and Duarte, Carlos M.

Subjects
*PHOTOSYNTHESIS, *POSIDONIA oceanica, *EFFECT of carbon dioxide on plants, *EFFECT of light on plants, *PLANT growth
Abstract

We evaluated the photosynthetic performance of Posidonia oceanica during short-term laboratory exposures to ambient and elevated temperatures (24–25 °C and 29–30 °C) warming and p CO 2 (380, 750 and 1000 ppm p CO 2 ) under normal and low light conditions (200 and 40 μmol photons m −2 s −1 respectively). Plant growth was measured at the low light regime and showed a negative response to warming. Light was a critical factor for photosynthetic performance, although we found no evidence of compensation of photosynthetic quantum efficiency in high light. Relative Electron Rate Transport (rETR max ) was higher in plants incubated in high light, but not affected by p CO 2 or temperature. The saturation irradiance (I k ) was negatively affected by temperature. We conclude that elevated CO 2 does not enhance photosynthetic activity and growth, in the short term for P. oceanica , while temperature has a direct negative effect on growth. Low light availability also negatively affected photosynthetic performance during the short experimental period examined here. Therefore increasing concentrations of CO 2 may not compensate for predicted future conditions of warmer water and higher turbidity for seagrass meadows. [ABSTRACT FROM AUTHOR]

Published
2017
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25. Seasonality and depth zonation of intertidal Halophila ovalis and Zostera japonica in Ha Long Bay (northern Vietnam)

Author

Huong, Tu Thi Lan, Vermaat, Jan E., Terrados, Jorge, Van Tien, Nguyen, Duarte, Carlos M., Borum, Jens, and Tri, Nguyen Hoang

Subjects
*HALOPHILIC microorganisms, *ZOSTERA, *SEAGRASSES
Abstract

Seasonality and depth zonation of two common intertidal northern Vietnamese seagrass species, Halophila ovalis and Zostera japonica, were investigated in a 50 m long intertidal transect from 1999 till 2001. Z. japonica occurred in the middle intertidal (1.2 m above mean chart datum to mean sea level at 2.1 m above chart datum). H. ovalis occurred deeper in the intertidal (between 1.0 and 1.4 m above chart datum). Based on seasonally different sensitivity to reciprocal transplants, it is concluded that this zonation is most likely due to different tolerances to low light availability (less in Z. japonica) and desiccation (less in H. ovalis). Both species reached maximum shoot densities in September–October with total biomasses around 70 g DW m−2. Flowering in Z. japonica occurred in April only, whilst H. ovalis flowered in November after the rainy season and again in April. Seasonality in density and biomass was apparent and similar between the two species. It was largely coupled to the rainy season, which brings spates of turbid water during May–August, thereby possibly limiting light availability and hence growth. [Copyright &y& Elsevier]

Published
2003
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