%0 Journal Article %1 citeulike:12903379 %A McDonald, Evan P. %A Erickson, John E. %A Kruger, Eric L. %D 2002 %J Functional Plant Biol. %K citeulikeExport co2, mass\_flow, tree, water %N 9 %P 1115--1120 %T <i>Research note</i>: Can decreased transpiration limit plant nitrogen acquisition in elevated CO₂? %U http://www.publish.csiro.au/paper/FP02007 %V 29 %X N acquisition often lags behind accelerated C gain in plants exposed to CO₂-enriched atmospheres. To help resolve the causes of this lag, we considered its possible link with stomatal closure, a common first-order response to elevated CO₂ that can decrease transpiration. Specifically, we tested the hypothesis that declines in transpiration, and hence mass flow of soil solution, can decrease delivery of mobile N to the root and thereby limit plant N acquisition. We altered transpiration by manipulating relative humidity (RH) and atmospheric CO₂. During a 7-d period, we grew potted cottonwood (<i>Populus deltoides</i> Bartr.) trees in humidified (76\% RH) and non-humidified (43\% RH) glasshouses ventilated with either CO₂-enriched or non-enriched air (\~1000 <i>vs </i>\~380 &\#956;mol mol^&\#8211;1). We monitored effects of elevated humidity and/or CO₂ on stomatal conductance, whole-plant transpiration, plant biomass gain, and N accumulation. To facilitate the latter, NO₃^&\#8211; enriched in ¹⁵N (5 atom\%) was added to all pots at the outset of the experiment. Transpiration and ¹⁵N accumulation decreased when either CO₂ or humidity were elevated. The disparity between N accumulation and accelerated C gain in elevated CO₂ led to a 19\% decrease in shoot N concentration relative to ambient CO₂. Across all treatments, ¹⁵N gain was positively correlated with root mass (<i>P</i>&lt;0.0001), and a significant portion of the remaining variation (44\%) was positively related to transpiration per unit root mass. At a given humidity, transpiration per unit leaf area was positively related to stomatal conductance. Thus, declines in plant N concentration and/or content under CO₂ enrichment may be attributable in part to associated decreases in stomatal conductance and transpiration.

@article{citeulike:12903379, abstract = {{N acquisition often lags behind accelerated C gain in plants exposed to CO₂-enriched atmospheres. To help resolve the causes of this lag, we considered its possible link with stomatal closure, a common first-order response to elevated CO₂ that can decrease transpiration. Specifically, we tested the hypothesis that declines in transpiration, and hence mass flow of soil solution, can decrease delivery of mobile N to the root and thereby limit plant N acquisition. We altered transpiration by manipulating relative humidity (RH) and atmospheric [CO₂]. During a 7-d period, we grew potted cottonwood (<i>Populus deltoides</i> Bartr.) trees in humidified (76\% RH) and non-humidified (43\% RH) glasshouses ventilated with either CO₂-enriched or non-enriched air (\~{}1000 <i>vs </i>\~{}380 \&\#956;mol mol^\&\#8211;1). We monitored effects of elevated humidity and/or CO₂ on stomatal conductance, whole-plant transpiration, plant biomass gain, and N accumulation. To facilitate the latter, NO₃^\&\#8211; enriched in ¹⁵N (5 atom\%) was added to all pots at the outset of the experiment. Transpiration and ¹⁵N accumulation decreased when either CO₂ or humidity were elevated. The disparity between N accumulation and accelerated C gain in elevated CO₂ led to a 19\% decrease in shoot N concentration relative to ambient CO₂. Across all treatments, ¹⁵N gain was positively correlated with root mass (<i>P</i>\&lt;0.0001), and a significant portion of the remaining variation (44\%) was positively related to transpiration per unit root mass. At a given humidity, transpiration per unit leaf area was positively related to stomatal conductance. Thus, declines in plant N concentration and/or content under CO₂ enrichment may be attributable in part to associated decreases in stomatal conductance and transpiration.}}, added-at = {2019-03-31T01:14:40.000+0100}, author = {McDonald, Evan P. and Erickson, John E. and Kruger, Eric L.}, biburl = {https://www.bibsonomy.org/bibtex/2e1ccb7667bb905fffc16d349313f1968/dianella}, citeulike-article-id = {12903379}, citeulike-linkout-0 = {http://www.publish.csiro.au/paper/FP02007}, day = 1, interhash = {a24b7636e4efdb9d0a1dd235654a0d81}, intrahash = {e1ccb7667bb905fffc16d349313f1968}, journal = {Functional Plant Biol.}, keywords = {citeulikeExport co2, mass\_flow, tree, water}, month = jan, number = 9, pages = {1115--1120}, posted-at = {2014-01-08 21:22:53}, priority = {3}, timestamp = {2019-03-31T01:16:26.000+0100}, title = {{<i>Research note</i>: Can decreased transpiration limit plant nitrogen acquisition in elevated CO₂?}}, url = {http://www.publish.csiro.au/paper/FP02007}, volume = 29, year = 2002 }