Old-growth CO2 flux measurements reveal high sensitivity to climate anomalies across seasonal, annual and decadal time scales

Wharton, Sonia; Falk, Matthias; Bible, Ken; Schroeder, M.

doi:10.1016/j.agrformet.2012.03.007

Cited by 45 publications

(31 citation statements)

References 68 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In 2003 (a moderate El Nino year), there was a negative NEP across all ecoregions. Eddy covariance flux towers in the region also reported record low or below average carbon sinks in 2003, with attribution focused on low precipitation and, especially, high temperatures (Thomas et al 2009;Wharton et al 2012). Regional carbon cycle responses to relatively warm dry years have also been reported in Europe (Reichstein et al 2006).…”

Section: Temporal Patternsmentioning

confidence: 92%

Regional carbon cycle responses to 25 years of variation in climate and disturbance in the US Pacific Northwest

et al. 2016

View full text Add to dashboard Cite

Variation in climate, disturbance regime, and forest management strongly influence terrestrial carbon sources and sinks. Spatially distributed, process-based, carbon cycle simulation models provide a means to integrate information on these various influences to estimate carbon pools and flux over large domains. Here we apply the Biome-BGC model over the four-state Northwest US region for the interval from 1986 to 2010. Landsat data were used to characterize disturbances, and forest inventory data were used to parameterize the model. The overall disturbance rate on forest land across the region was 0.8 % year -1 , with 49 % as harvests, 28 % as fire, and 23 % as pest/pathogen. Net ecosystem production (NEP) for the 2006-2010 interval on forestland was predominantly positive (a carbon sink) throughout the region, with maximum values in the Coast Range, intermediate values in the Cascade Mountains, and relatively low values in the Inland Rocky Mountain ecoregions. Localized negative NEPs were mostly associated with recent disturbances. There was large interannual variation in regional NEP, with notably low values across the region in 2003, which was also the warmest year in the interval. The recent (2006)(2007)(2008)(2009)(2010) net ecosystem carbon balance (NECB) was positive for the region (14.4 TgC year -1 ). Despite a lower area-weighted mean NECB, public forestland contributed a larger proportion to the total NECB because of its larger area. Aggregated forest inventory data and inversion modeling are beginning to provide opportunities for evaluating model-simulated regional carbon stocks and fluxes.

show abstract

Section: Temporal Patternsmentioning

confidence: 92%

Regional carbon cycle responses to 25 years of variation in climate and disturbance in the US Pacific Northwest

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Such alterations in carbon dynamics have been observed in several grasslands and forests worldwide (Amiro et al 2006;Barr et al 2007;Ciais et al 2005;Wagle et al 2015a). Although old-growth stands are traditionally viewed as net carbon sources or carbon neutral (DeBell and Franklin 1987) due to increased respiration and decreased photosynthesis, previous studies have suggested that oldgrowth forests can still be large carbon sinks under favorable climatic conditions (Carey et al 2001;Luyssaert et al 2008;Wharton et al 2012). The carbon source or sink strength of any stand age depends on local climatic US-Wrc Fig.…”

Section: Discussionmentioning

confidence: 99%

Differential responses of carbon and water vapor fluxes to climate among evergreen needleleaf forests in the USA

et al. 2016

View full text Add to dashboard Cite

Introduction: Understanding the differences in carbon and water vapor fluxes of spatially distributed evergreen needleleaf forests (ENFs) is crucial for accurately estimating regional or global carbon and water budgets and when predicting the responses of ENFs to current and future climate. Methods: We compared the fluxes of ten AmeriFlux ENF sites to investigate cross-site variability in net ecosystem exchange of carbon (NEE), gross primary production (GPP), and evapotranspiration (ET). We used wavelet cross-correlation analysis to examine responses of NEE and ET to common climatic drivers over multiple timescales and also determined optimum values of air temperature (T a ) and vapor pressure deficit (VPD) for NEE and ET.

show abstract

“…At or adjacent to 15 sites, ecosystem-atmosphere gas exchange has been measured using the eddy-covariance technique (e.g., Barford et al, 2001;Kume et al, 2011;Thomas et al, 2011;Kosugi et al, 2012;Soderberg et al, 2012;Wharton et al, 2012;Zhang et al, 2012). There is not a specific CTFS-ForestGEO protocol.…”

Section: Bio-micrometeorologymentioning

confidence: 99%

CTFS‐ForestGEO: a worldwide network monitoring forests in an era of global change

Anderson‐Teixeira

Davies

Bennett

et al. 2014

Global Change Biology

494

439

View full text Add to dashboard Cite

Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses to global change. Within very large plots (median size 25 ha), all stems ≥1 cm diameter are identified to species, mapped, and regularly recensused according to standardized protocols. CTFS-ForestGEO spans 25°S-61°N latitude, is generally representative of the range of bioclimatic, edaphic, and topographic conditions experienced by forests worldwide, and is the only forest monitoring network that applies a standardized protocol to each of the world's major forest biomes. Supplementary standardized measurements at subsets of the sites provide additional information on plants, animals, and ecosystem and environmental variables. CTFS-ForestGEO sites are experiencing multifaceted anthropogenic global change pressures including warming (average 0.61°C), changes in precipitation (up to AE30% change), atmospheric deposition of nitrogen and sulfur compounds (up to 3.8 g N m À2 yr À1 and 3.1 g S m À2 yr À1), and forest fragmentation in the surrounding landscape (up to 88% reduced tree cover within 5 km). The broad suite of measurements made at CTFS-ForestGEO sites makes it possible to investigate the complex ways in which global change is impacting forest dynamics. Ongoing research across the CTFSForestGEO network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in an era of global change.

show abstract

Old-growth CO2 flux measurements reveal high sensitivity to climate anomalies across seasonal, annual and decadal time scales

Cited by 45 publications

References 68 publications

Regional carbon cycle responses to 25 years of variation in climate and disturbance in the US Pacific Northwest

Regional carbon cycle responses to 25 years of variation in climate and disturbance in the US Pacific Northwest

Differential responses of carbon and water vapor fluxes to climate among evergreen needleleaf forests in the USA

CTFS‐ForestGEO: a worldwide network monitoring forests in an era of global change

Contact Info

Product

Resources

About