Samuel T. Dunn , Joseph von Fischer

Slides:



Advertisements
Similar presentations
Quantifying carbon allocation to mycorrhizal fungi by temperate forest tree species across a nitrogen availability gradient Shersingh Joseph Tumber-Davila.
Advertisements

Carbon flux at the scale up field of GLBRC. The Eddy Covariance cluster towers Terenzio Zenone 1 Jiquan Chen 1 Burkhard Wilske 1 and Mike Deal 1 Kevin.
The Carbon Cycle: Global to local Ruth Varner, PhD.
Carbon Cycle Basics Ranga Myneni Boston University 1/12 Egon Schiele ( ) Autumn Sun 1.
MITIGATING CLIMATE CHANGE. WHAT WE KNOW The level of greenhouse gases in the atmosphere have increased, causing the Earth’s temperature to rise. One greenhouse.
Amanda Brennan 1, Elise Pendall 1, Dave Risk 2, Yolima Carrillo 3 1 University of Wyoming, Department of Botany and Program in Ecology, Laramie, WY 82071,
Anthropogenic Influences on the Global Carbon Cycle and its Implications for the Future Abstract Carbon makes up approximately 50% of the dry weight of.
1 1 Fig.7 - The cavity ring-down. I.Vigano 1, R.Holzinger 1, A.van Dijk 2 & T. Röckmann 1 1 Institute for Marine and Atmospheric Research, Utrecht University,
IntroductionIntroduction Land-use change or intensification can influence the dynamics and storage of soil organic matter (SOM) and the extent of carbon.
Methods During summer 2011 we measured freshwater DOC uptake ( k ; day -1 ) using short-term, dark bottle bioassay incubations: where C 0 and C t represent.
Introduction: Globally, atmospheric concentrations of CO 2 are rising, and are expected to increase forest productivity and carbon storage. However, forest.
Carbon Flows in Forest Ecosystems with relation to climate change Andy Cross Using stable isotopes to study carbon flows in forest ecosystems with relation.
Field research was conducted at the University of Minnesota Rosemount Research and Outreach Center. The experiment was conducted in a 17 ha agricultural.
Chamber and biometric flux measurments for upscaling C- budgets: NACP Tier 3 Efforts Peter Weishampel Dept. Soil, Water, and Climate University of Minnesota.
Site Description This research is being conducted as a part of the Detritus Input and Removal Treatments Project (DIRT), a cross-continental experiment.
Source waters and flow paths in an alpine catchment, Colorado, Front Range, United States Fengjing Liu, Mark W. Williams, and Nel Caine 2004.
Cycling of Matter in Ecosystems. Biogeochemical Cycles Matter cannot be made or destroyed. All water and nutrients must be produced or obtained from chemicals.
Ecological Succession Ecosystems are constantly changing in response to natural and human disturbances.
Earth is a unique planet...
Focus on “deep soil column” Spatial patterns Mechanism that control development and function Implications for ecology, biogeochemistry and hydrology What.
The Use of Natural Abundance of 13 CO 2 to Determine Soil Respiration Components in an Agro-Ecosystem a School of Environmental Sciences, University of.
Production.
Interannual Variations in Methane Emissions and Net Ecosystem Exchange in a Temperate Peatland Claire Treat Mount Holyoke College Research and.
Results A B C A. Year to year variation in water regimes result in changes in plant zones which affect the distribution of dissolved oxygen. The marsh’s.
Greenhouse Gases Emission and Carbon Sequestration in Agro-Ecosystems under Long-Term No-Till: Implications for Global Warming Mitigation Pierre-André.
Dissolved Gas Concentrations in Two Reservoir Systems Kyle Hacker, Christopher Whitney, Drew Robison, Wilfred Wollheim Introduction/Background Methods.
Pulsed emission of methane (CH 4 ) from a small eutrophic lake Arianto Santoso David Hamilton photo credit: Joint Conference.
Samuel T. Dunn 1, 2, Andrew G. Bunn 3, John D. Schade 1
Human Energy Systems Unit Activity 4.3: Carbon Fluxes
Ch 20 Global Warming Part one.
Chapter 3 Ecosystems and Energy
Chapter 3 Ecosystems and Energy
Nitrogen and Phosphorus Concentrations
Faith Simitz and Benjamin D. Duval
Why is it important that nutrients cycle?
The Effects of Various Aquaculture Biodeposits on Nutrient Flux at the Sediment-Water Interface in Maine Libby Gorse, Aria Amirbahman Department of Civil.
Biogeochemical cycles
Kyle Hacker1, Andrew Robison2, Wilfred Wollheim2
October 4 SC.912.E.7.1 Biogeochemical Cycles
Effects of a raised water table on greenhouse gas emissions and celery yield from agricultural peat under climate warming conditions Magdalena Matysek¹,
Open stomata: allows for gas exchange: CO2 in and water vapor out
Cycles in the Environment Populations and Biodiversity
Carbon: Transformations in Matter and Energy
Biology Department, Colby College, 2014
Relationships and Graphing
Atmospheric Greenhouse Gas Levels
CH19: Carbon Sinks and Sources
TRIODE TUBES.
Climate Change.
CH19: Carbon Sinks and Sources
Cycles Within an Ecosystem
The Carbon Cycle.
Unit 2: Ecology 2.2 Cycles of Matter.
Revised by Daniel Brown
Moisture Controls on Trace Gas Fluxes From Semiarid Soils
Ecology.
The Water Cycle.
Biogeochemical Cycles
Radjewski – Ecology Unit’ AP Biology
Carbon: Transformations in Matter and Energy
Water, Carbon, and Nitrogen
Mrs. K. S. K. College , Beed DEPT OF GEOGRAPHY. Mr. Chavan A. D. Assit
Summary and Future Work
The Water Cycle.
Water, Carbon, and Nitrogen
Water, Carbon, and Nitrogen
Global Warming.
Understanding: Skills: 4.3 Carbon cycle
Investigating Daily Variation in Lotic Prairie Ecosystems
Hydrogen Production by Microwave Pyrolysis of Glycerol
Presentation transcript:

Samuel T. Dunn , Joseph von Fischer A pulse-label experiment to determine the biophysical kinetics of different carbon pools for methane emissions in a Carex aquatilis dominated wetland B31D-0449 Samuel T. Dunn , Joseph von Fischer 1. Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA. 2. Dept. of Biology, Colorado State University, Fort Collins, CO, USA 200 100 Introduction: Methane is a potent greenhouse gas that is produced by microbes using organic carbon under anoxic conditions. Work by King and Reeburgh [2002] using radioisotope tracers has shown that carbon fixed via photosynthesis is emitted as methane within 24 hours. Given the importance of plant productivity for methane emissions, it is imperative that the underlying dynamics of this process be understood in order to improve the reliability of modeled methane emissions. The objective of my research is to determine the dynamics governing carbon flow in the rhizosphere leading to methane emission a) b) Diagram. 2 (a) Conceptual layout of experimental plots within study site. The distance between plots was 2m on all sides. Picture. 3 (b) Preparing to add the 13C-Acetate label via injection into the study plot. Injections were made at 3 points to improve distribution Figure.1 Keeling plot intercepts (d13C) for methane emitted from sample plots over ~26 hours. Values are normalized to the accepted value of d13C-CH4=-47‰ for the control plot. r2 values for all keeling plot intercepts were greater than 0.9 Picture 1. Samples were collected from a high alpine wetland within the Glacial Lakes Ecosystem Experimental Site (GLEES) near Centennial WY. This particular wetland site is listed at 99% Carex aquatilis Picture. 4 Chamber used in field measurements of CH4, CO2, and d13C-CH4. Chamber was cooled and mixed using a heat exchanger and battery powered fan. Diagram. 1 Conceptual schematic of the experimental design. Plant tissue includes both above and belowground biomass, “OM” is soil organic matter exuded from root tissue and includes acetate, and “CH4“ is the dissolved methane pool in the rhizosphere. Picture 2. Chamber measurements were made using a field portable greenhouse gas analyzer (FGGA)(pictured) and a field portable methane carbon isotope analyzer (MCIA) from Los Gatos Research at 5hz. Discussion: Preliminary data suggests that the movement of carbon through multiple soil pools can successfully be tracked using stable isotope tracers. In this study, the emission of added 13C as methane was only clear in two of three amendments: Dissolved 13C-CH4 added directly to the rhizosphere was emitted to the atmosphere within one hour of addition (Figure 1). The isotopic signal decayed following an exponential curve over the next 24 hours (Figure 2). This is most likely due to the physical limitations of diffusion within the rhizosphere prior to release via plant aerenchyma. Dissolved 13C-Acetate added to the rhizosphere was gradually converted to, and emitted as, 13C-CH4. The increase in the isotopic composition of emitted methane from the labeled acetate is linear and did not reach a peak and decline within 24 hours of addition (Figure 1). 13C-CO2 added to the chamber headspace does not appear to have been converted to methane in clearly quantifiable amounts. However, the slight rise in relative isotopic enrichment of emitted methane around four hours after addition may be due to the isotopic label that was added. Follow up work with additional labeled material in a more controlled setting is planned. Methane emissions are controlled by physical and biological processes. The temporal importance of different carbon pools for methane emission may be greater than we had originally thought, which means that an understanding of methane transport in the rhizosphere is important for modeling purposes. Methods: A series of 0.5 x0.5m plots were established in a high alpine wetland dominated by the sedge Carex aquatilis. Plant carbon uptake and methane emissions were determined using a field-deployable greenhouse gas analyzer (FGGA) One day’s worth of emitted CH4-C was added to each of the three experimental plots as 13C-CO2, 13C-Acetate, and 13C-CH4 (Diagrams 1 and 2) The isotopic composition of emitted CH4 was tracked over a 24 hour period using a field-deployable methane carbon isotope analyzer. Keeling plot analysis was used to determine the isotopic composition of emitted methane. Figure. 2 The isotopic composition of methane emitted from the plot amended with 13C-CO2 decreased over a 24 hour period following an exponential decay curve after peaking within an hour of the addition. This trend is indicative of physical processes controlling the release of methane from the rhizosphere. Future Work: Due to the historic drought in CO and WY this past summer, field work was unable to be completed once the wetland had dried up. Ongoing work in the greenhouse will confirm the results presented and increase available data on pool sizes. A comparative field study using this isotope addition method is being planned for next season and will incorporate plant community composition as a factor. These data will be used to parameterize the model of methane production, consumption, and transport we are currently developing. Acknowledgments: I would like to thank the von Fischer lab for their help processing samples and with field work. Additionally I would like to thank Elsie Denton, Whitney Mowll, Tony Vorster, Guy Litt, and Mary Ballard for their assistance with field work. Special thanks to the GLEES and USFS scientists who provided logistical and site support.