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Title: CARBON DIOXIDE FLUXES IN A CENTRAL HARDWOODS OAK-HICKORY FOREST ECOSYSTEM

Abstract

A long-term experiment to measure carbon and water fluxes was initiated in 2004 as part of the Ameriflux network in a second-growth oak-hickory forest in central Missouri. Ecosystem-scale (~ 1 km2) canopy gas exchange (measured by eddy-covariance methods), vertical CO2 profile sampling and soil respiration along with meteorological parameters were monitored continuously. Early results from this forest located on the western margin of the Eastern Deciduous Forest indicated high peak rates of canopy CO2 uptake (35-40 ?mol m-2 s-1) during the growing season. Canopy CO2 profile measurements indicated substantial accumulation of CO2 (~500 ppm) near the surface in still air at night, venting of this buildup in the morning hours under radiation-induced turbulent air flow, and small vertical gradients of CO2 during most of the subsequent light period with minimum CO2 concentrations in the canopy. Flux of CO2 from the soil ranged from 2 to 8 ?mol m-2 s-1 and increased with temperature. Data from this site and others in the network will also allow characterization of regional spatial variation in carbon fluxes as well as inter-annual differences attributable to climatic events such as droughts.

Authors:
 [1];  [2];  [2];  [3];  [2];  [2];  [1]
  1. University of Missouri
  2. ORNL
  3. NOAA ATDD
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
930815
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: 15th Central Hardwood Forest Conference, Knoxville, TN, USA, 20060227, 20060301
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; AIR; AIR FLOW; BUILDUP; CARBON; CARBON DIOXIDE; DROUGHTS; ECOSYSTEMS; FORESTS; MISSOURI; RESPIRATION; SAMPLING; SOILS; WATER

Citation Formats

Pallardy, Stephen G., Gu, Lianhong, Hanson, Paul J, Meyers, T. P., Wullschleger, Stan D, Yang, Bai, and Hosman, K. P.. CARBON DIOXIDE FLUXES IN A CENTRAL HARDWOODS OAK-HICKORY FOREST ECOSYSTEM. United States: N. p., 2007. Web.
Pallardy, Stephen G., Gu, Lianhong, Hanson, Paul J, Meyers, T. P., Wullschleger, Stan D, Yang, Bai, & Hosman, K. P.. CARBON DIOXIDE FLUXES IN A CENTRAL HARDWOODS OAK-HICKORY FOREST ECOSYSTEM. United States.
Pallardy, Stephen G., Gu, Lianhong, Hanson, Paul J, Meyers, T. P., Wullschleger, Stan D, Yang, Bai, and Hosman, K. P.. 2007. "CARBON DIOXIDE FLUXES IN A CENTRAL HARDWOODS OAK-HICKORY FOREST ECOSYSTEM". United States. doi:.
@article{osti_930815,
title = {CARBON DIOXIDE FLUXES IN A CENTRAL HARDWOODS OAK-HICKORY FOREST ECOSYSTEM},
author = {Pallardy, Stephen G. and Gu, Lianhong and Hanson, Paul J and Meyers, T. P. and Wullschleger, Stan D and Yang, Bai and Hosman, K. P.},
abstractNote = {A long-term experiment to measure carbon and water fluxes was initiated in 2004 as part of the Ameriflux network in a second-growth oak-hickory forest in central Missouri. Ecosystem-scale (~ 1 km2) canopy gas exchange (measured by eddy-covariance methods), vertical CO2 profile sampling and soil respiration along with meteorological parameters were monitored continuously. Early results from this forest located on the western margin of the Eastern Deciduous Forest indicated high peak rates of canopy CO2 uptake (35-40 ?mol m-2 s-1) during the growing season. Canopy CO2 profile measurements indicated substantial accumulation of CO2 (~500 ppm) near the surface in still air at night, venting of this buildup in the morning hours under radiation-induced turbulent air flow, and small vertical gradients of CO2 during most of the subsequent light period with minimum CO2 concentrations in the canopy. Flux of CO2 from the soil ranged from 2 to 8 ?mol m-2 s-1 and increased with temperature. Data from this site and others in the network will also allow characterization of regional spatial variation in carbon fluxes as well as inter-annual differences attributable to climatic events such as droughts.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2007,
month = 1
}

Conference:
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