The rapid increase in atmospheric CO 2 concentrations ( C a ) has resulted in extensive research efforts to understand its impact on terrestrial ecosystems, especially carbon balance. Despite these efforts, there are relatively few data comparing net ecosystem exchange of CO 2 between the atmosphere and the biosphere ( NEE ), under both ambient and elevated C a . Here we report data on annual sums of CO 2 ( NEE net ) for 19 ye...

Wetlands evapotranspire more water than other ecosystems, including agricultural, forest and grassland ecosystems. However, the effects of elevated atmospheric carbon dioxide (CO 2 ) concentration ( C a ) on wetland evapotranspiration (ET) are largely unknown. Here, we present data on 12 years of measurements of ET, net ecosystem CO 2 exchange (NEE), and ecosystem water use efficiency (EWUE, i.e. NEE/ET) at 13:00–15:00 hours i...

Elevated atmospheric carbon dioxide concentrations ([CO 2 ]) generally increase plant photosynthesis in C 3 species, but not in C 4 species, and reduce stomatal conductance in both C 3 and C 4 plants. In addition, tissue nitrogen concentration ([N]) often fails to keep pace with enhanced carbon gain under elevated CO 2 , particularly in C 3 species. While these responses are well documented in many species, implications for pl...

Increased atmospheric CO 2 concentration ( Ca ) produces a short‐term stimulation of photosynthesis and plant growth across terrestrial ecosystems. However, the long‐term response remains uncertain and is thought to depend on environmental constraints. In the longest experiment on natural ecosystem response to elevated Ca , we measured the shoot‐density, biomass and net CO 2 exchange (NEE) responses to elevated Ca from 1987 to...