Light-dark O2 dynamics in submerged leaves of C3 and C4 halophytes under increased dissolved CO2: clues for saltmarsh response to climate change.

Waterlogging and submergence are the major constraints to which wetland plants are subjected, with inevitable impacts on their physiology and productivity. Global warming and climate change, as driving forces of sea level rise, tend to increase such submersion periods and also modify the carbonate chemistry of the water column due to the increased concentration of CO2 in the atmosphere. In the present work, the underwater O2 fluxes in the leaves of two abundant Mediterranean halophytes were evaluated at different levels of dissolved CO2.

Unveiling Zn hyperaccumulation in Juncus acutus: implications on the electronic energy fluxes and on oxidative stress with emphasis on non-functional Zn-chlorophylls.

Juncus acutus arises as possible hyperaccumulator specie, tolerating exogenous Zn concentrations as high as 60 mM. Zinc concentrations here detected in seedlings germinated in the presence high Zn concentrations, were above the described upper toxic levels for higher plants. Even at the highest Zn concentration, growth inhibition only accounted to approximately 30% of control seedlings biomass, presenting an ECâ‚…â‚€ value in the range of 10-20 mM of metal.

Photochemical and biophysical feedbacks of C₃ and C₄ Mediterranean halophytes to atmospheric CO₂ enrichment confirmed by their stable isotope signatures.

According the latest predictions, an increase of about two times in atmospheric CO2 concentrations, is expected to occur by the end of this century. In order to understand the effects of this atmospheric composition changes on two abundant Mediterranean halophytes (Halimione portulacoides and Spartina maritima), mesocosmos trials were performed simulating two atmospheric CO2 environments (380 ppm and 760 ppm of CO2 respectively). The two chosen halophyte species present different metabolic characteristics: H.

Biophysical probing of Spartina maritima photo-system II changes during prolonged tidal submersion periods.

Submergence is one of the major constrains affecting wetland plants, with inevitable impacts on their physiology and productivity. Global warming as a driving force of sea level rise, tend to increase the submersion periods duration. Photosynthesis biophysical probing arise as an important tool to understand the energetics underlying plant feedback to these constrains.

Halophyte anti-oxidant feedback seasonality in two salt marshes with different degrees of metal contamination: search for an efficient biomarker.

Salt marshes can be affected by metal contamination when near a polluted area, and this excessive concentration of metals is a source of stress in plants. Production of proteins, flavonoids, phenolic compounds and anti-oxidant feedback can be used as biomarkers, as well to assess the suitability of halophytes to function as a biomonitors. Through monitoring the anti-oxidative feedback in Halimione portulacoides (L.

Ecophysiological adaptations of two halophytes to salt stress: photosynthesis, PS II photochemistry and anti-oxidant feedback--implications for resilience in climate change.

Halimione portulacoides and Sarcocornia fruticosa commonly exhibit a reddish coloration especially in high evaporation periods, due to betacyanin production in response to stress. Although sharing the same area in salt marshes, they present different strategies to overcome salinity stress. While S.