By measuring titratable acidity, gas exchange parameters, mesophyll succulence, and (13)C/(12)C ratios, we have shown that Cissus quadrangularis L. has C(3)-like leaves and stems with Crassulacean acid metabolism (CAM). In addition, the nonsucculent leaves show the diurnal fluctuations in organic acids termed recycling despite the fact that all CO(2) uptake and stomatal opening occurs during th...

In the light, photosynthesis provides carbon for metabolism and growth. In the dark, plant growth depends on carbon reserves that were accumulated during previous light periods. Many plants accumulate part of their newly-fixed carbon as starch in their leaves in the day and remobilise it to support metabolism and growth at night. The daily rhythms of starch accumulation and degradation are dyna...

Background and Aims In photosynthetic organisms exposure to high light induces the production of reactive oxygen species (ROS), such as hydrogen peroxide (H2O2), which in part is prevented by non-photochemical quenching (NPQ). As one of the most stable and longest-lived ROS, H2O2 is involved in key signalling pathways in development and stress responses, although in excess it can induce damage....

Coral reef metabolism underpins ecosystem function and is defined by the processes of photosynthesis, respiration, calcification, calcium carbonate dissolution. However, relationships between these physiological at organismal level their interactions with light remain unclear. We examined metabolic rates across a range photosynthesising calcifiers in Caribbean: scleractinian corals Acropora cer...

Soil respiration (Rs) plays a key role in the carbon balance of forest ecosystems. There is growing evidence that Rs is strongly correlated with canopy photosynthesis; however, how Rs is linked to aboveground attributes at various phenological stages, on the seasonal and diurnal scale, remains unclear. Using an automated closed dynamic chamber system, we assessed the seasonal and diurnal patter...

The acclimation of plants to light has been studied extensively, yet little is known about the effect of dynamic fluctuations in light on plant phenotype and acclimatory responses. We mimicked natural fluctuations in light over a diurnal period to examine the effect on the photosynthetic processes and growth of Arabidopsis (Arabidopsis thaliana). High and low light intensities, delivered via a ...

To date, diurnal rhythms of emotions have been studied with real-time data collection methods mostly in relatively small samples. The Day Reconstruction Method (DRM), a new survey instrument that reconstructs the emotions of a day, is examined as a method for enabling large-scale investigations of rhythms. Diurnal cycles were observed for 12 emotion adjectives in 909 women over a working day. B...