PubAg

Main content area

Search

46  Search Results

« Previous | 1 - 20 of 46 |
Number of results to display per page

Search Results

1. Estimating soil carbon sequestration under elevated CO₂ by combining carbon isotope labelling with soil carbon cycle modelling

Author:
NIKLAUS, PASCAL A.; FALLOON, PETE
Source:
Global change biology 2006 v.12 no.10 pp. 1909-1921
ISSN:
1354-1013
Subject:
carbon; carbon dioxide; carbon dioxide enrichment,   etc   ; biomass; carbon sequestration; carbon sinks; grasslands; herbaceous plants; isotope labeling; isotopes; leaf conductance; models; primary productivity; soil water;     Show all 14 Subjects
Abstract:
... Elevated CO₂ concentrations generally stimulate grassland productivity, but herbaceous plants have only a limited capacity to sequester extra carbon (C) in biomass. However, increased primary productivity under elevated CO₂ could result in increased transfer of C into soils where it could be stored for prolonged periods and exercise a negative feedback on the rise in atmospheric CO₂. Measuring soi ...
DOI:
10.1111/j.1365-2486.2006.01215.x

2. The turnover of carbon pools contributing to soil CO₂ and soil respiration in a temperate forest exposed to elevated CO₂ concentration

Author:
TANEVA, LINA; PIPPEN, JEFFREY S.; SCHLESINGER, WILLIAM H.; GONZALEZ-MELER, MIQUEL A.
Source:
Global change biology 2006 v.12 no.6 pp. 983-994
ISSN:
1354-1013
Subject:
carbon; carbon dioxide; carbon sinks,   etc   ; air; climate change; ecosystems; forests; free air carbon dioxide enrichment; fumigation; models; oxidation; soil depth; soil organic matter; soil respiration;     Show all 14 Subjects
Abstract:
... Soil carbon is returned to the atmosphere through the process of soil respiration, which represents one of the largest fluxes in the terrestrial C cycle. The effects of climate change on the components of soil respiration can affect the sink or source capacity of ecosystems for atmospheric carbon, but no current techniques can unambiguously separate soil respiration into its components. Long-term ...
DOI:
10.1111/j.1365-2486.2006.01147.x

3. Bicarbonate kinetics in Indian males

Author:
Raj, T.; Kuriyan, R.; Kurpad, A. V.
Source:
Journal of biosciences 2006 v.31 no.2 pp. 273-280
ISSN:
0250-5991
Subject:
carbon; carbon dioxide,   etc   ; amino acids; animal organs; bicarbonates; fatty acids; glucose; males; models; oxidation; radionuclides;     Show all 11 Subjects
Abstract:
... Measurement of rates ofin vivo substrate oxidation such as that of glucose, fatty acids and amino acids, are based on tracer (¹⁴C or¹³C) data, and often depend on the isotopic content of expired CO₂. The recovery of tracer-labelled CO₂ generated from the oxidation of¹³C labelled substrates may not be 100% over short term. This can lead to underestimation of oxidation rate of substrates, and conseq ...
DOI:
10.1007/BF02703920

4. Will Simplified Modalities and Procedures Make More Small-Scale Forestry Projects Viable Under the Clean Development Mechanism?

Author:
Locatelli, Bruno; Pedroni, Lucio
Source:
Mitigation and adaptation strategies for global change 2006 v.11 no.3 pp. 621-643
ISSN:
1381-2386
Subject:
carbon dioxide; carbon markets,   etc   ; economic incentives; global change; models; nonindustrial private forests; prices; reforestation; viability;     Show all 9 Subjects
Abstract:
... Simplified modalities and procedures (M&P) are expected to increase the viability of small-scale project activities under the Clean Development Mechanism (CDM). A small-scale afforestation or reforestation (AR) project is defined as a project removing less than 8 kilotons of carbon dioxide equivalent (CO₂e) per year. Depending on the project type and the method for measuring scale, 8 kilotons of C ...
DOI:
10.1007/s11027-006-5274-y

5. ¹⁴C - a tool for separation of autotrophic and heterotrophic soil respiration

Author:
HAHN, VOLKER; HÖGBERG, PETER; BUCHMANN, NINA
Source:
Global change biology 2006 v.12 no.6 pp. 972-982
ISSN:
1354-1013
Subject:
carbon; carbon dioxide,   etc   ; ecosystems; forest stands; forests; girdling; models; soil; soil respiration; trees; Germany; Sweden;     Show all 12 Subjects
Abstract:
... We assessed the potential of using ¹⁴C contents of soil respired CO₂ to calculate the contributions of heterotrophic and autotrophic respiration to total soil respiration. The partitioning of these fluxes is of utmost importance to evaluate implications of environmental change on soil carbon cycling and sequestration. At three girdled forest stands in Sweden and Germany, where the tree root (autot ...
DOI:
10.1111/j.1365-2486.2006.001143.x

6. Contrasting effects of climate and CO₂ on Amazonian ecosystems since the last glacial maximum

Author:
BEERLING, DAVID J.; MAYLE, FRANCIS E.
Source:
Global change biology 2006 v.12 no.10 pp. 1977-1984
ISSN:
1354-1013
Subject:
carbon dioxide; carbon sequestration,   etc   ; biomass; climate; climate change; ecosystems; models; rain forests;     Show all 8 Subjects
Abstract:
... The nature of Amazonian ecosystem responses to the large-scale environmental changes characterizing glacial-interglacial cycles is poorly understood. We investigated this issue with a series of transient, continuous 21 000-year simulations using a dynamic process-based ecosystem model. Our results indicate that the Amazon Basin has been dominated by evergreen rain forests since the last glacial ma ...
DOI:
10.1111/j.1365-2486.2006.01228.x

7. The global-scale temperature and moisture dependencies of soil organic carbon decomposition: an analysis using a mechanistic decomposition model

Author:
Ise, Takeshi; Moorcroft, Paul R.
Source:
Biogeochemistry 2006 v.80 no.3 pp. 217-231
ISSN:
0168-2563
Subject:
carbon dioxide; soil organic carbon,   etc   ; terrestrial ecosystems; data collection; models; soil; environmental factors; climate change; temperature;     Show all 9 Subjects
Abstract:
... Since the decomposition rate of soil organic carbon (SOC) varies as a function of environmental conditions, global climate change is expected to alter SOC decomposition dynamics, and the resulting changes in the amount of CO₂ emitted from soils will feedback onto the rate at which climate change occurs. While this soil feedback is expected to be significant because the amount of SOC is substantial ...
DOI:
10.1007/s10533-006-9019-5

8. Estimating High Latitude Carbon Fluxes With Inversions Of Atmospheric CO₂

Author:
Dargaville, Roger; Baker, David; Rödenbeck, Christian; Rayner, Peter; Ciais, Philippe
Source:
Mitigation and adaptation strategies for global change 2006 v.11 no.4 pp. 769-782
ISSN:
1381-2386
Subject:
carbon; carbon dioxide; carbon sinks,   etc   ; aboveground biomass; climate; information systems; inventories; latitude; models; remote sensing; soil; uncertainty; Asia; Europe; North America;     Show all 15 Subjects
Abstract:
... Atmospheric inversions have proven to be useful tools, showing for example the likely existence of a large terrestrial carbon sink in the northern mid-latitudes. However, as we go to smaller spatial scales the uncertainties in the inversions increase rapidly, and the task of finding the distribution of the sink between North America, Europe and Asia has been shown to be very difficult. The uncerta ...
DOI:
10.1007/s11027-005-9018-1

9. Establishing A Earth Observation Product Service For The Terrestrial Carbon Community: The Globcarbon Initiative

Author:
Plummer, Stephen; Arino, Olivier; Simon, Muriel; Steffen, Will
Source:
Mitigation and adaptation strategies for global change 2006 v.11 no.1 pp. 97-111
ISSN:
1381-2386
Subject:
carbon; carbon cycle; carbon dioxide,   etc   ; biosphere; climate; climate change; greenhouse gases; humans; leaf area index; models; photosynthetically active radiation; research programs; satellites; vegetation;     Show all 14 Subjects
Abstract:
... 'Greenhouse gases', especially carbon dioxide, are intimately connected to climate change. To understand the future evolution of the climate system and find ways to manage the concentration of atmospheric carbon dioxide, the processes and feedbacks that drive the carbon cycle must first be understood. However, our current knowledge of spatial and temporal patterns is uncertain, particularly over l ...
DOI:
10.1007/s11027-006-1012-8

10. Long-term growth of soybean at elevated [CO₂] does not cause acclimation of stomatal conductance under fully open-air conditions

Author:
LEAKEY, ANDREW D.B.; BERNACCHI, CARL J.; ORT, DONALD R.; LONG, STEPHEN P.
Source:
Plant, cell and environment 2006 v.29 no.9 pp. 1794-1800
ISSN:
0140-7791
Subject:
carbon dioxide; free air carbon dioxide enrichment,   etc   ; acclimation; biogeochemical cycles; gas exchange; humidity; leaves; models; photosynthesis; soybeans; stomatal conductance;     Show all 11 Subjects
Abstract:
... Accurately predicting plant function and global biogeochemical cycles later in this century will be complicated if stomatal conductance (gs) acclimates to growth at elevated [CO₂], in the sense of a long-term alteration of the response of gs to [CO₂], humidity (h) and/or photosynthetic rate (A). If so, photosynthetic and stomatal models will require parameterization at each growth [CO₂] of interes ...
DOI:
10.1111/j.1365-3040.2006.01556.x

11. Evidence for a plasmalemma-based CO₂ concentrating mechanism in Laminaria saccharina

Author:
Mercado, Jesús M.; Andría, Jesús R.; Pérez-Llorens, J. Lucas; Vergara, Juan J.; Axelsson, Lennart
Source:
Photosynthesis research 2006 v.88 no.3 pp. 259-268
ISSN:
0166-8595
Subject:
carbon; carbon dioxide,   etc   ; Laminaria; buffers; carbonic acid; inhibitory concentration 50; models; molecular weight; pH; photosynthesis; plasma membrane; titration;     Show all 12 Subjects
Abstract:
... A kinetic analysis of the photosynthesis inhibition by buffers allowed quantification of some components of the carbon concentrating mechanism (CCM) of the brown macroalga Laminaria saccharina. The CCM was based on the presence of acid regions outside the plasma membrane that increased the CO₂ concentration available for photosynthesis by 10-20 times above that of the bulk medium at alkaline pH. F ...
DOI:
10.1007/s11120-006-9039-y

12. Diurnal, seasonal and annual variation in net ecosystem CO₂ exchange of an alpine shrubland on Qinghai-Tibetan plateau

Author:
ZHAO, LIANG; LI, YINGNIAN; XU, SHIXIAO; ZHOU, HUAKUN; GU, SONG; YU, GUIRUI; ZHAO, XINQUAN
Source:
Global change biology 2006 v.12 no.10 pp. 1940-1953
ISSN:
1354-1013
Subject:
carbon dioxide; carbon; carbon sinks,   etc   ; Dasiphora fruticosa subsp. fruticosa; eddy covariance; shrublands; soil temperature; leaf area index; models; net ecosystem exchange; night temperature; Cambisols; growing season; rain; soil water; ecosystems; ecosystem respiration; biomass; grasslands; China;     Show all 20 Subjects
Abstract:
... Thus far, grassland ecosystem research has mainly been focused on low-lying grassland areas, whereas research on high-altitude grassland areas, especially on the carbon budget of remote areas like the Qinghai-Tibetan plateau is insufficient. To address this issue, flux of CO₂ were measured over an alpine shrubland ecosystem (37°36'N, 101°18'E; 325 above sea level [a. s. l.]) on the Qinghai-Tibetan ...
DOI:
10.1111/j.1365-2486.2006.01197.x

13. An organic carbon budget for the Mississippi River turbidity plume and plume contributions to air-sea CO2 fluxes and bottom water hypoxia

Author:
Green, Rebecca E.; Bianchi, Thomas S.; Dagg, Michael J.; Walker, Nan D.; Breed, Greg A.
Source:
Estuaries and coasts 2006 v.29 no.4 pp. 579-597
ISSN:
1559-2723
Subject:
carbon; carbon dioxide,   etc   ; anaerobic conditions; drawdown; food webs; metabolism; models; oxygen; primary productivity; salinity; seasonal variation; spring; summer; suspended sediment; turbidity; Mississippi River;     Show all 16 Subjects
Abstract:
... We investigated seasonal variability in organic carbon (OC) budgets using a physical-biological model for the Mississippi River turbidity plume. Plume volume was calculated from mixed layer depth and area in each of four salinity subregions based on an extensive set of cruise data and satellite-derived suspended sediment distributions. These physical measurements were coupled with an existing food ...
DOI:
10.1007/BF02784284

14. Irradiance, temperature and rainfall influence leaf dark respiration in woody plants: evidence from comparisons across 20 sites

Author:
Wright, Ian J.; Reich, Peter B.; Atkin, Owen K.; Lusk, Christopher H.; Tjoelker, Mark G.; Westoby, Mark
Source:
The new phytologist 2006 v.169 no.2 pp. 309-319
ISSN:
0028-646X
Subject:
carbon; carbon dioxide,   etc   ; climate; climate change; leaf area; leaves; light intensity; longevity; models; nitrogen content; photosynthesis; rain; temperature; vegetation; woody plants;     Show all 15 Subjects
Abstract:
... • Leaf dark respiration (R) is one of the most fundamental physiological processes in plants and is a major component of terrestrial CO₂ input to the atmosphere. Still, it is unclear how predictably species vary in R along broad climate gradients. • Data for R and other key leaf traits were compiled for 208 woody species from 20 sites around the world. We quantified relationships between R and sit ...
DOI:
10.1111/j.1469-8137.2005.01590.x

15. Stand age-related effects on soil respiration in a first rotation Sitka spruce chronosequence in central Ireland

Author:
SAIZ, GUSTAVO; BYRNE, KENNETH A.; BUTTERBACH-BAHL, KLAUS; KIESE, RALF; BLUJDEA, VIOREL; FARRELL, EDWARD P.
Source:
Global change biology 2006 v.12 no.6 pp. 1007-1020
ISSN:
1354-1013
Subject:
carbon dioxide; soil organic carbon,   etc   ; Picea sitchensis; afforestation; biomass; chronosequences; fine roots; forest stands; models; nitrogen content; root systems; site preparation; soil respiration; soil types; trenching; Ireland;     Show all 16 Subjects
Abstract:
... The effect of stand age on soil respiration and its components was studied in a first rotation Sitka spruce chronosequence composed of 10-, 15-, 31-, and 47-year-old stands established on wet mineral gley in central Ireland. For each stand age, three forest stands with similar characteristics of soil type and site preparation were used. There were no significant differences in total soil respirati ...
DOI:
10.1111/j.1365-2486.2006.01145.x

16. Sensitivity of the last glacial inception to initial and surface conditions

Author:
Kubatzki, Claudia; Claussen, Martin; Calov, Reinhard; Ganopolski, Andrey
Source:
Climate dynamics 2006 v.27 no.4 pp. 333-344
ISSN:
0930-7575
Subject:
carbon dioxide,   etc   ; climate; ice; models; solar radiation; vegetation; Greenland; North America;     Show all 8 Subjects
Abstract:
... We investigate the sensitivity of simulations of the last glacial inception (LGI) with respect to initial (size of the Greenland ice sheet) and surface (state of ocean/vegetation) conditions and two different CO₂ reconstructions. Utilizing the CLIMBER-2 Earth system model, we obtain the following results: (a) ice-sheet expansion in North America at the end of the Eemian can be reduced or even comp ...
DOI:
10.1007/s00382-006-0136-6

17. On the Sensitivity of the Atmosphere to the Doubling of the Carbon Dioxide Concentration and on Water Vapour Feedback

Author:
Barrett, Jack; Bellamy, David; Hug, Heinz
ISSN:
2048-4070
Subject:
carbon dioxide,   etc   ; climate; climate change; energy; models; surface temperature; water vapor;     Show all 7 Subjects
Abstract:
... This paper represents a criticism of the Intergovernmental Panel on Climate Change (IPCC) use of the value 0.5 K (W m⁻²)⁻¹ for the climate sensitivity parameter, λ. A simple model is introduced which shows that the non-radiative effect of water vapour is a negative feedback ensuring that the Earth's surface temperature is cooler by some 17°C than if it did not participate in the energy budget. ...
DOI:
10.1260/095830506778644198

18. Modelling responses of pine savannas to climate change and large-scale disturbance

Author:
Beckage, Brian; Gross, Louis J.; Platt, William J.
Source:
Applied vegetation science 2006 v.9 no.1 pp. 75-82
ISSN:
1402-2001
Subject:
carbon dioxide,   etc   ; climate; fires; forests; global warming; hurricanes; landscapes; models; mortality; savannas; temperature; tree mortality; trees;     Show all 13 Subjects
Abstract:
... Global warming can potentially influence ecological communities through altered disturbance regimes in addition to increased temperatures. We investigate the response of pine savannas in the southeastern United States to global warming using a simple Lotka-Volterra competition model together with predicted changes to fire and hurricane disturbance regimes with global climate change. In the southea ...
DOI:
10.1111/j.1654-109X.2006.tb00657.x

19. El Niño-mean state-seasonal cycle interactions in a multi-model ensemble

Author:
Guilyardi, Eric
Source:
Climate dynamics 2006 v.26 no.4 pp. 329-348
ISSN:
0930-7575
Subject:
carbon dioxide,   etc   ; climate; energy; greenhouse gases; models; seasonal variation; trade cycles; trade winds;     Show all 8 Subjects
Abstract:
... The modelled El Niño-mean state-seasonal cycle interactions in 23 coupled ocean-atmosphere GCMs, including the recent IPCC AR4 models, are assessed and compared to observations and theory. The models show a clear improvement over previous generations in simulating the tropical Pacific climatology. Systematic biases still include too strong mean and seasonal cycle of trade winds. El Niño amplitude ...
DOI:
10.1007/s00382-005-0084-6

20. The ability of climate envelope models to predict the effect of climate change on species distributions

Author:
HIJMANS, ROBERT J.; GRAHAM, CATHERINE H.
Source:
Global change biology 2006 v.12 no.12 pp. 2272-2281
ISSN:
1354-1013
Subject:
carbon dioxide,   etc   ; biogeography; climate change; climatic factors; entropy; models; physiology; prediction;     Show all 8 Subjects
Abstract:
... Climate envelope models (CEMs) have been used to predict the distribution of species under current, past, and future climatic conditions by inferring a species' environmental requirements from localities where it is currently known to occur. CEMs can be evaluated for their ability to predict current species distributions but it is unclear whether models that are successful in predicting current di ...
DOI:
10.1111/j.1365-2486.2006.01256.x