Physiological responses of red mangroves to the climate in the Florida Everglades


Autoria(s): Barr, Jordan G.; Fuentes, Jose D.; Engel, Vic; Zieman, Joseph C.
Data(s)

01/01/2009

Resumo

This manuscript reports the findings of physiological studies of red mangrove (Rhizophora mangle L.) conducted from June to August 2001 and from May to June 2003 in the Florida Everglades. In situ physiological measurements were made using environmentally controlled gas exchange systems. The field investigations were carried out to define how regional climate constrains mangrove physiology and ecosystem carbon assimilation. In addition, maximum carboxylation and photosynthetic active radiation (PAR) limited carbon assimilation capacities were investigated during the summer season to evaluate whether ecophysiological models developed for mesophyte plant species can be applied to mangroves. Under summertime conditions in the Florida Everglades, maximum foliar carbon dioxide (CO2) assimilation rates reached 18 μmol CO2 m−2 s−1. Peak molar stomatal conductance to water vapor (H2O) diffusion reached 300 mmol H2O m−2 s−1. Maximum carboxylation and PAR‐limited carbon assimilation rates at the foliage temperature of 30°C attained 76.1 ± 23.4 μmol CO2 m−2 s−1 and 128.1 ± 32.9 μmol (e−) m−2 s−1, respectively. Environmental stressors such as the presence of hypersaline conditions and high solar irradiance loading (>500 W m−2 or >1000 μmoles of photons m−2 s−1 of PAR) imposed sharp reductions in carbon assimilation rates and suppressed stomatal conductance. On the basis of both field observations and model analyses, it is also concluded that existing ecophysiological models need to be modified to consider the influences of hypersaline and high radiational loadings on the physiological responses of red mangroves.

Formato

application/pdf

Identificador

https://digitalcommons.fiu.edu/fce_lter_journal_articles/20

https://digitalcommons.fiu.edu/cgi/viewcontent.cgi?article=1020&context=fce_lter_journal_articles

Publicador

FIU Digital Commons

Direitos

default

Fonte

FCE LTER Journal Articles

Palavras-Chave #carbon assimilation #photosynthesis #photoinhibition #stomatal conductance #transpiration #mangroves
Tipo

text