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DeForest JL, Chen J, McNulty SG. Leaf litter is an important mediator of soil respiration in an oak-dominated forest. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2009; 53:127-134. [PMID: 19037664 DOI: 10.1007/s00484-008-0195-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2008] [Revised: 10/30/2008] [Accepted: 10/31/2008] [Indexed: 05/27/2023]
Abstract
The contribution of the organic (O) horizon to total soil respiration is poorly understood even though it can represent a large source of uncertainty due to seasonal changes in microclimate and O horizon properties due to plant phenology. Our objectives were to partition the CO(2) effluxes of litter layer and mineral soil from total soil respiration (SR) and determine the relative importance of changing temperature and moisture mediating the fluxes. We measured respiration in an oak-dominated forest with or without the O horizon for 1 year within the Oak Openings Region of northwest Ohio. Mineral soil and O horizon respiration were subtracted from mineral soil respiration (MSR) to estimate litter respiration (LR). Measurements were grouped by oak phenology to correlate changes in plant activity with respiration. The presence of the O horizon represented a large source of seasonal variation in SR. The timing of oak phenology explained some of the large changes in both SR and LR, and their relationship with temperature and moisture. The contribution to SR of respiration from the mineral soil was greatest during pre-growth and pre-dormancy, as evident by the low LR:MSR ratios of 0.65 +/- 0.10 (mean +/- SE) and 0.69 +/- 0.03, respectively, as compared to the other phenophases. Including moisture increased our ability to predict MSR and SR during the growth phenophase and LR for every phenophase. Temperature and moisture explained 85% of the variation in MSR, but only 60% of the variation in LR. The annual contribution of O horizon to SR was 48% and the ratio of litter to soil respiration was tightly coupled over a wide range of environmental conditions. Our results suggest the presence of the O horizon is a major mediator of SR.
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Affiliation(s)
- Jared L DeForest
- Department of Environmental and Plant Biology, Ohio University, Athens, 45701-2979, USA
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52
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Miao Z, Xu M, Lathrop RG, Wang Y. Comparison of the A-Cc curve fitting methods in determining maximum ribulose 1.5-bisphosphate carboxylase/oxygenase carboxylation rate, potential light saturated electron transport rate and leaf dark respiration. PLANT, CELL & ENVIRONMENT 2009; 32:109-22. [PMID: 19154228 DOI: 10.1111/j.1365-3040.2008.01900.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
A review of the literature revealed that a variety of methods are currently used for fitting net assimilation of CO2-chloroplastic CO2 concentration (A-Cc) curves, resulting in considerable differences in estimating the A-Cc parameters [including maximum ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco) carboxylation rate (Vcmax), potential light saturated electron transport rate (Jmax), leaf dark respiration in the light (Rd), mesophyll conductance (gm) and triose-phosphate utilization (TPU)]. In this paper, we examined the impacts of fitting methods on the estimations of Vcmax, Jmax, TPU, Rd and gm using grid search and non-linear fitting techniques. Our results suggested that the fitting methods significantly affected the predictions of Rubisco-limited (Ac), ribulose 1,5-bisphosphate-limited (Aj) and TPU-limited (Ap) curves and leaf photosynthesis velocities because of the inconsistent estimate of Vcmax, Jmax, TPU, Rd and gm, but they barely influenced the Jmax : Vcmax, Vcmax : Rd and Jmax : TPU ratio. In terms of fitting accuracy, simplicity of fitting procedures and sample size requirement, we recommend to combine grid search and non-linear techniques to directly and simultaneously fit Vcmax, Jmax, TPU, Rd and gm with the whole A-Cc curve in contrast to the conventional method, which fits Vcmax, Rd or gm first and then solves for Vcmax, Jmax and/or TPU with V(cmax), Rd and/or gm held as constants.
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Affiliation(s)
- Zewei Miao
- Grant F. Walton Center for Remote Sensing & Spatial Analysis, Rutgers University, 14 College Farm Road, New Brunswick, NJ 08901-8551, USA and
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53
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Sun J, Peng C, McCaughey H, Zhou X, Thomas V, Berninger F, St-Onge B, Hua D. Simulating carbon exchange of Canadian boreal forests. Ecol Modell 2008. [DOI: 10.1016/j.ecolmodel.2008.03.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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54
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Pendall E, Rustad L, Schimel J. Towards a predictive understanding of belowground process responses to climate change: have we moved any closer? Funct Ecol 2008. [DOI: 10.1111/j.1365-2435.2008.01506.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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56
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Rocha AV, Goulden ML. Large interannual CO2
and energy exchange variability in a freshwater marsh under consistent environmental conditions. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008jg000712] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Adrian V. Rocha
- Department of Earth System Science; University of California; Irvine California USA
| | - Michael L. Goulden
- Department of Earth System Science; University of California; Irvine California USA
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57
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Steppe K, De Pauw DJ, Lemeur R. Validation of a dynamic stem diameter variation model and the resulting seasonal changes in calibrated parameter values. Ecol Modell 2008. [DOI: 10.1016/j.ecolmodel.2008.07.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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58
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Wang Y, Bauerle WL, Reynolds RF. Predicting the growth of deciduous tree species in response to water stress: FVS-BGC model parameterization, application, and evaluation. Ecol Modell 2008. [DOI: 10.1016/j.ecolmodel.2008.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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59
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Pepper DA, McMurtrie RE, Medlyn BE, Keith H, Eamus D. Mechanisms linking plant productivity and water status for a temperate Eucalyptus forest flux site: analysis over wet and dry years with a simple model. FUNCTIONAL PLANT BIOLOGY : FPB 2008; 35:493-508. [PMID: 32688806 DOI: 10.1071/fp08125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Accepted: 06/04/2008] [Indexed: 06/11/2023]
Abstract
A simple process-based model was applied to a tall Eucalyptus forest site over consecutive wet and dry years to examine the importance of different mechanisms linking productivity and water availability. Measured soil moisture, gas flux (CO2, H2O) and meteorological records for the site were used. Similar levels of simulated H2O flux in 'wet' and 'dry' years were achieved when water availability was not confined to the first 1.20 m of the soil profile, but was allowed to exceed it. Although the simulated effects of low soil and atmospheric water content on CO2 flux, presumably via reduction in stomatal aperture, also acted on transpiration, they were offset in the dry year by a higher vapour-pressure deficit. A sensitivity analysis identified the processes that were important in wet versus dry years, and on an intra-annual timeframe. Light-limited productivity dominated in both years, except for the driest period in the dry year. Vapour-pressure deficit affected productivity across more of each year than soil moisture, but both effects were larger in the dry year. The introduction of a reduced leaf area tended to decrease sensitivity in the dry year. Plant hydraulic architecture that increases plant available water, maximises productivity per unit water use and achieves lower sensitivity to low soil moisture levels should minimise production losses during dry conditions.
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Affiliation(s)
- David A Pepper
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Ross E McMurtrie
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Belinda E Medlyn
- Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Heather Keith
- The Fenner School of Environment and Society, Australian National University, Canberra, ACT 0200, Australia
| | - Derek Eamus
- Institute for Water and Environmental Resource Management and Department of Environmental Sciences, University of Technology, Sydney, NSW 2007, Australia
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60
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Spatio-temporal patterns of forest carbon dioxide exchange based on global eddy covariance measurements. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/s11430-008-0087-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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61
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Weng E, Luo Y. Soil hydrological properties regulate grassland ecosystem responses to multifactor global change: A modeling analysis. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jg000539] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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62
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Sang W, Su H. Interannual NPP variation and trend of Picea schrenkiana forests under changing climate conditions in the Tianshan Mountains, Xinjiang, China. Ecol Res 2008. [DOI: 10.1007/s11284-008-0521-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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63
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64
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Knohl A, Baldocchi DD. Effects of diffuse radiation on canopy gas exchange processes in a forest ecosystem. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jg000663] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Alexander Knohl
- Institute for Plant Sciences; ETH Zürich; Zürich Switzerland
- Policy and Management, Department of Environmental Sciences; University of California; Berkeley California USA
| | - Dennis D. Baldocchi
- Policy and Management, Department of Environmental Sciences; University of California; Berkeley California USA
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65
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Ryu Y, Baldocchi DD, Ma S, Hehn T. Interannual variability of evapotranspiration and energy exchange over an annual grassland in California. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009263] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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66
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67
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Desai AR, Moorcroft PR, Bolstad PV, Davis KJ. Regional carbon fluxes from an observationally constrained dynamic ecosystem model: Impacts of disturbance, CO2fertilization, and heterogeneous land cover. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jg000264] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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68
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Zweifel R, Steppe K, Sterck FJ. Stomatal regulation by microclimate and tree water relations: interpreting ecophysiological field data with a hydraulic plant model. JOURNAL OF EXPERIMENTAL BOTANY 2007; 58:2113-31. [PMID: 17490998 DOI: 10.1093/jxb/erm050] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Dynamics in microclimate and physiological plant traits were studied for Pubescent oak and Scots pine in a dry inner-alpine valley in Switzerland, at a 10 min resolution for three consecutive years (2001-2003). As expected, stomata tended to close with increasing drought in air and soil. However, stomatal aperture in oak was smaller than in pine under relatively wet conditions, but larger under dry conditions. To explore underlying mechanisms, a model was applied that (i) quantifies water relations within trees from physical principles (mechanistic part) and (ii) assumes that signals from light, stomatal aperture, crown water potential, and tree water deficit in storage pools control stomata (systemic part). The stomata of pine showed a more sensitive response to increasing drought because both factors, the slowly changing tree water deficit and the rapidly changing crown water potential, closed the stomata. By contrast, the stomata of oak became less drought-sensitive as the closing signal of crown water potential was opposed by the opening signal of tree water deficit. Moreover, parameter optimization suggests that oak withdrew more water from the storage pools and reduced leaf water potentials to lower levels, without risking serious damage by cavitation. The new model thus suggests how the hydraulic water flow and storage system determines the responses in stomatal aperture and transpiration to drought at time scales ranging from hours to multiple years, and why pine and oak might differ in such responses. These differences explain why oaks are more efficient competitors during drought periods, although this was not the case in the extremely dry year 2003, which provoked massive leaf loss and, from July onwards, physiological activity almost ceased.
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Affiliation(s)
- Roman Zweifel
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Forest Ecosystem Processes, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.
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69
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Deforest JL, Noormets A, McNulty SG, Sun G, Tenney G, Chen J. Phenophases alter the soil respiration-temperature relationship in an oak-dominated forest. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2006; 51:135-44. [PMID: 16874506 DOI: 10.1007/s00484-006-0046-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2006] [Revised: 05/18/2006] [Accepted: 05/29/2006] [Indexed: 05/11/2023]
Abstract
Soil respiration (SR) represents a major component of forest ecosystem respiration and is influenced seasonally by environmental factors such as temperature, soil moisture, root respiration, and litter fall. Changes in these environmental factors correspond with shifts in plant phenology. In this study, we examined the relationship between canopy phenophases (pre-growth, growth, pre-dormancy, and dormancy) and SR sensitivity to changes in soil temperature (T(S)). SR was measured 53 times over 550 days within an oak forest in northwest Ohio, USA. Annual estimates of SR were calculated with a Q(10) model based on T(S) on a phenological (PT), or annual timescale (AT), or T(S) and soil volumetric water content (VWC) on a phenological (PTM) or annual (ATM) timescale. We found significant (p<0.01) difference in apparent Q(10) from year 2004 (1.23) and year 2005 (2.76) during the growth phenophase. Accounting for moisture-sensitivity increased model performance compared to temperature-only models: the error was -17% for the ATM model and -6% for the PTM model. The annual models consistently underestimated SR in summer and overestimated it in winter. These biases were reduced by delineating SR by tree phenophases and accounting for variation in soil moisture. Even though the bias of annual models in winter SR was small in absolute scale, the relative error was about 91%, and may thus have significant implications for regional and continental C balance estimates.
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Affiliation(s)
- Jared L Deforest
- Department of Earth, Ecological and Environmental Sciences, University of Toledo, Toledo, OH 43606-3390, USA.
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70
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Grant R, Zhang Y, Yuan F, Wang S, Hanson P, Gaumont-Guay D, Chen J, Black T, Barr A, Baldocchi D, Arain A. Intercomparison of techniques to model water stress effects on CO2 and energy exchange in temperate and boreal deciduous forests. Ecol Modell 2006. [DOI: 10.1016/j.ecolmodel.2006.02.035] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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71
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A multiyear evaluation of a Dynamic Global Vegetation Model at three AmeriFlux forest sites: Vegetation structure, phenology, soil temperature, and CO2 and H2O vapor exchange. Ecol Modell 2006. [DOI: 10.1016/j.ecolmodel.2005.11.031] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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72
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Baldocchi D, Tang J, Xu L. How switches and lags in biophysical regulators affect spatial-temporal variation of soil respiration in an oak-grass savanna. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jg000063] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Dennis Baldocchi
- Ecosystem Sciences Division, Department of Environmental Science, Policy and Management; University of California; Berkeley California USA
| | - Jianwu Tang
- Ecosystem Sciences Division, Department of Environmental Science, Policy and Management; University of California; Berkeley California USA
| | - Liukang Xu
- Ecosystem Sciences Division, Department of Environmental Science, Policy and Management; University of California; Berkeley California USA
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73
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Grant R, Arain A, Arora V, Barr A, Black T, Chen J, Wang S, Yuan F, Zhang Y. Intercomparison of techniques to model high temperature effects on CO2 and energy exchange in temperate and boreal coniferous forests. Ecol Modell 2005. [DOI: 10.1016/j.ecolmodel.2005.01.060] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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74
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Falge E, Reth S, Brüggemann N, Butterbach-Bahl K, Goldberg V, Oltchev A, Schaaf S, Spindler G, Stiller B, Queck R, Köstner B, Bernhofer C. Comparison of surface energy exchange models with eddy flux data in forest and grassland ecosystems of Germany. Ecol Modell 2005. [DOI: 10.1016/j.ecolmodel.2005.01.057] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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75
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Ito A, Muraoka H, Koizumi H, Saigusa N, Murayama S, Yamamoto S. Seasonal variation in leaf properties and ecosystem carbon budget in a cool-temperate deciduous broad-leaved forest: simulation analysis at Takayama site, Japan. Ecol Res 2005. [DOI: 10.1007/s11284-005-0100-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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76
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Affiliation(s)
- Aimee T Classen
- Environmental Sciences Divisions, Oak Ridge National Laboratory, TN 37381-6422, USA.
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77
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Barbour MM, Hunt JE, Dungan RJ, Turnbull MH, Brailsford GW, Farquhar GD, Whitehead D. Variation in the degree of coupling between delta13C of phloem sap and ecosystem respiration in two mature Nothofagus forests. THE NEW PHYTOLOGIST 2005; 166:497-512. [PMID: 15819913 DOI: 10.1111/j.1469-8137.2005.01329.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Day-to-day variability in the carbon isotope composition of phloem sap (delta13Chd) and ecosystem respiratory CO2 (delta13CR) were measured to assess the tightness of coupling between canopy photosynthesis (delta13Chd) and ecosystem respiration (delta13CR) in two mature Nothofagus solandri (Hook. f.) forests in New Zealand. Abundant phloem-tapping scale insects allowed repeated, nondestructive access to stem phloem sap 1-2 m above ground. delta13Chd was compared with delta13C predicted by an environmentally driven, process-based canopy photosynthesis model. Keeling plots of within-canopy CO2 were used to estimate delta13CR. By including a lag of 3 d, there was good agreement in the timing and direction of variation in delta13Chd and predictions by the canopy photosynthesis model, suggesting that delta13Chd represents a photosynthesis-weighted, integrative record of canopy photosynthesis and conductance. Significant day-to-day variability in delta13CR was recorded at one of the two forests. At this site, delta13CR reflected variability in delta13Chd only on days with <2 mm rain. We conclude that the degree of coupling between canopy photosynthesis and ecosystem respiration varies between sites, and with environmental conditions at a single site.
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