The composition and successional status of a forest affect carbon storage and net ecosystem productivity, yet it remains unclear whether elevated atmospheric carbon dioxide (CO2) will impact rates and trajectories of forest succession. We examined how CO2 enrichment (+200 microL CO2/L air differential) affects forest succession through growth and survivorship of tree seedlings, as part of the D...

Enrichment is widely used as tool for managing fearfulness, undesirable behaviors, and stress in captive animals, and for studying exploration and personality. Inconsistencies in previous studies of physiological and behavioral responses to enrichment led us to hypothesize that enrichment and its removal are stressful environmental changes to which the hormone corticosterone and fearfulness, ac...

We describe an open leaf gas exchange system coupled to a tunable diode laser (TDL) spectroscopy system enabling measurement of the leaf respiratory CO(2) flux and its associated carbon isotope composition (delta(13)C(Rl)) every 3 min. The precision of delta(13)C(Rl) measurement is comparable to that of traditional mass spectrometry techniques. delta(13)C(Rl) from castor bean (Ricinus communis ...

Carbon dioxide enrichment changes the balance of photosynthetic limitations due to water, nitrogen, and light. This paper examines the role of stomata in these changes by comparing enrichment responses predicted by an optimality-based tree growth model, DESPOT, using three alternative 'setpoints' for stomatal acclimation: leaf water potential (psi(l)-setpoint), the ratio of intercellular to amb...

Stable isotopes are increasingly used to infer sources of nutrient enrichment and trophic linkages in coastal marine systems, although the utility of these tools often depends upon a predictable expression of δ15N and δ13C signatures by primary producers. Accordingly, we examined how tissue δ15N and δ13C values change in the common coastal marine alga Ulva pertusa Kjellman under contrasting lig...

The responses of macroalgae to ocean acidification could be altered by availability of macronutrients, such as ammonium (NH4+). This study determined how the opportunistic macroalga, Ulva australis responded to simultaneous changes in decreasing pH and NH4+ enrichment. This was investigated in a week-long growth experiment across a range of predicted future pHs with ambient and enriched NH4+ tr...

We report on a new phenomenon of molecular nuclear spin isomers conversion in the field of resonant laser radiation. It is based on the isomer-selective optical excitation and the difference of conversion rates for excited and unexcited molecules. We expect the considerable magnitude of the effect for all molecules which absorb the radiation of existing lasers. In a recent work [1] a phenomenon...