NASA/TMm2000-209891, Vol. 229

Technical Report Series on the

Boreal Ecosystem-Atmosphere Study (BOREAS)

Forrest G. Hall and Sara K. Conrad, Editors

Volume 229

BOREAS TGB-5 CO2, CH4, and CO

Chamber Flux Data over the NSA

Roger Burke and Richard Zepp

U.S. Environmental Protection Agency, Athens, Georgia

National Aeronautics and

Space Administration

Goddard Space Flight Center

Greenbelt, Maryland 20771

November 2000

https://ntrs.nasa.gov/search.jsp?R=20010022518 2018-05-14T19:02:11+00:00Z
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NASA/TMm2000-209891, Vol. 229

Technical Report Series on the

Boreal Ecosystem-Atmosphere Study (BOREAS)

Forrest G. Hall and Sara K. Conrad, Editors

Volume 229

BOREAS TGB-5 CO2, CH4, and CO

Chamber Flux Data over the NSA

Roger Burke and Richard Zepp

U.S. Environmental Protection Agency, Athens, Georgia

National Aeronautics and

Space Administration

Goddard Space Flight Center

Greenbelt, Maryland 20771

November 2000
NASA Center for AeroSpace Information

7121 Standard Drive

Hanover, MD 21076-1320

Price Code: A17

Available from:

National Technical Information Service

5285 Port Royal Road

Springfield, VA 22161

Price Code: A10
BOREAS TGB-5 CO2, CH4, and CO Chamber Flux Data over the NSA

Roger Burke, Richard G. Zepp

Summary

The BOREAS TGB-5 team collected a variety of trace gas concentration and flux measurements at

several NSA sites. This data set contains carbon dioxide (CO2), methane (CH4), and carbon monoxide

(CO) chamber flux measurements conducted in 1994 at upland forest sites that experienced

stand-replacement fires. These measurements were acquired to understand the impact of fires on soil

biogeochemistry and related changes in trace gas exchange in boreal forest soils. Relevant ancillary

data, including data concerning the soil temperature, solar irradiance, and information from nearby

unburned control sites, are included to provide a basis for modeling the regional impacts of fire and

climate changes on trace gas biogeochemistry. The data are provided in tabular ASCII files.

Table of Contents

1) Data Set Overview

2) Investigator(s)

3) Theory of Measurements

4) Equipment

5) Data Acquisition Methods

6) Observations

7) Data Description

8) Data Organization

9) Data Manipulations

10) Errors

11) Notes

12) Application of the Data Set

13) Future Modifications and Plans

14) Software

15) Data Access

16) Output Products and Availability

17) References

18) Glossary of Terms

19) List of Acronyms

20) Document Information

1. Data Set Overview

1.1 Data Set Identification

BOREAS TGB-05 CO2, CH4, and CO Chamber Flux Data over the NSA

1.2 Data Set Introduction

These measurements are required to understand the impact of fires on soil biogeochemistry and

related changes in trace gas exchange in boreal forest soils. Relevant ancillary data, including data

concerning the soil temperature and solar irradiance, are included to provide a basis for modeling the

regional impacts of fire and climate changes on trace gas biogeochemistry.

Page 1
1.3 Objective/Purpose

The objective of this study is to examine the effects of fire on soil-atmosphere fluxes of trace

carbon gases (carbon dioxide [CO2], methane [CHIn] and carbon monoxide [CO]) in upland black

spruce and jack pine ecosystems located within the BOReal Ecosystem-Atmosphere Study (BOREAS)

Northern Study Area (NSA) near Thompson, Manitoba.

1.4 Summary of Parameters

This data set contains measurements of ambient CO2, CH4, and CO)concentrations; CO2, CH4,

and CO fluxes; ambient and soil temperatures; and solar irradiance.

1.5 Discussion

The soil-atmosphere exchange of CO2 is an important component of the carbon budget of the

boreal forest biome. Soil-atmosphere exchange of CH4 and CO in the boreal biome has major effects

on the atmospheric content of these radiatively and chemically important trace gases. Closed chamber

techniques with gas chromatography were used to determine the soil surface flux of CO2, CH4, and

CO at five BOREAS auxiliary sites in the NSA that were exposed to intense stand-replacement fires

during the 7-year period prior to 1994. Flux data were also obtained at nearby control sites. Relevant

ancillary data were simultaneously obtained at the sites. The experiments were conducted from the

beginning of June through the end of August 1995.

The results from this study indicate that upland soils in burned boreal forests are generally net

sources of both CO2 and CO, but net sinks of atmospheric CHIn. Soil temperatures in these burned

sites were generally higher than those observed in nearby unburned controls. Soil respiration includes

both root respiration and decomposition of soil organic matter (SOM). Despite the loss of root

respiration in the bum sites, soil respiration was nearly the same in the bum sites as in unburned

controls. This indicates that enhancement of SOM decomposition by the warming of the soil offset the

reduction in root respiration. In sites exposed to the most intense fires, however, where surface

organic matter was considerably reduced and converted to charcoal by fire, soil respiration was

significantly reduced compared to other sites that were investigated. CH4 sinks were generally greater

in the well-drained jack pine stands than in black spruce stands. CO fluxes are affected by thermal and

photochemical production at the soil surface and by microbial consumption deeper in the soil. Thus,

CO fluxes in the open bum sites were positive during daylight, whereas the fluxes were negative in the

unburned forest soils.

1.6 Related Data Sets

BOREAS TGB-01 Soil CH4 and CO2 Profile Data over NSA Tower Sites

BOREAS TGB-01 CH4 and CO2 Chamber Flux Data from NSA Tower Sites

BOREAS TGB-01 CH4 Concentration and Flux Data from NSA Tower Sites

BOREAS TGB-01 SF6 Chamber Flux Data over NSA Jack Pine Sites

BOREAS TGB-03 CO2 and CH4 Chamber Flux Data over the NSA

2. Investigator(s)

2.1 Investigator(s) Name and Title

Dr. Richard G. Zepp and Dr. Roger A. Burke

U.S. Environmental Protection Agency (EPA)

Athens, GA

2.2 Title of Investigation

Trace Gas Exchange in the Boreal Forest Biome: Effects of Fire and Beaver Activity

Page 2
2.3 Contact Information

Contact 1:

Dr. Richard G. Zepp

U.S. EPA

960 College Station Road

Athens, GA 30605

(706) 355-8117

zepp.richard@epamail.epa.gov

Contact 2:

Jeffrey A. Newcomer

Raytheon ITSS

Code 923

NASA GSFC

Greenbelt, MD 20771

(301) 286-7858

(301) 286-0239 (fax)

Jeffrey.Newcomer@ gsfc.nasa.gov

3. Theory of Measurements

The CO2, CH4, and CO fluxes at the surface of the soil are important components of the carbon budget

of the boreal forest. Stand-replacement fires may affect the soil-surface fluxes of these gases. Fire

removes the canopy and part of the moss, lichen, and shrub cover, thus altering soil temperature,

moisture, and nutrient composition. Models of trace gas biogeochemistry in the boreal forest, such as

CENTURY, require field measurements of these fluxes in order to calibrate the models and test their

predicted fluxes. In order to understand and quantify the carbon gas exchange in these systems, it is

necessary to measure their exchange under a variety of conditions in unburned plots and burned plots

of various postburn ages.

In particular, CO exchange from the forest ecosystem floor is a poorly understood process that may

exhibit a significant effect on the ambient CO levels. The forest floor may act as both a source and sink

for CO. Sink activity is believed to be the result of consumption of CO by microbial activity, while

production is primarily the result of thermal and photochemical decomposition of living and dead

organic matter. The net exchange from the forest floor will therefore be determined by the relative

source and sink strengths of these processes. Some parameters that are believed to be important in CO

exchange are temperature, moisture content, soil nutrient levels, SOM content, and light intensity.

4. Equipment

4.1 Sensor/Instrument Description

• CH4 and CO2 were measured using a Karl Gas Chromatograph (GC) equipped with

flame-ionization detector (FID) (for CI_) and thermal conductivity detector (TCD) (for CO2).

CO was measured using a Trace Analytical (Menlo Park, CA) RGA-3 GC. This instrument

isolates CO, and reacts with HgO, producing Hg vapor. The Hg vapor is detected by atomic

absorbance. Samples are injected through an injection loop (0.5 or 1 mL).

• Aluminum chamber bases (0.215-m inner diameter [i.d.]) were used for isolating a section of

the forest floor. The chambers were anchored with three or four spikes that were 0.20 m in

length. The chambers were also equipped with a cylindrical skirt to prevent lateral diffusion of

gases. Three skirt sizes were used depending on the ecosystem type: 5 cm, 10 cm, and 20 cm.

The opening of the base had a trough filled with water to provide support and seal the

chamber top.

Page 3
Light measurementsweremadewith anInternationalLight ILl700 radiometerusingprobes

for variouslightregions(SED623for visible,SED240for ultraviolet[UV]-A, andSED033

for UV-B).

Soiltemperaturewasmeasuredwith aportabletemperatureprobe(Cole-Palmerthermistor

thermometerL-08110-20).

Soilwatercontentwasmeasuredusinga 1502BTimeDomainReflectometer(TDR)[Toppet

al., 1980].

4.1.1 Collection Environment

Measurementsweremadeatopensitesthathadexperiencedstand-replacement fireswithin the

prior 7 yearsor atnearbyshadedcontrolforestsitesthathadnotburnedfor atleast70years.Thesoil

temperaturesandsolarirradianceweretypicallymuchhigherattheburnedsitesthanatthecontrol

sites.Datawerecollectedunderavarietyof ambientemperaturesrangingfromnear0 °Ctonear28

°C.

4.1.2 Source/Platform

All measurements were made on the ground.

4.1.3 Source/Platform Mission Objectives

The mission objective was to measure soil surface CO2, CH4, and CO fluxes and relevant ancillary

data in fire scars and nearby controls.

4.1.4 Key Variables

CO2, CH4, and CO flux; soil temperature; soil moisture content; and light intensity (total, UV-A,

and UV-B).

4.1.5 Principles of Operation

The chamber assays for CO, CO2, and CH4 followed the methods established by Hutchinson and

Livingston [1993]. Analysis of CH4 [Crill, 1991] was conducted with 0.5% precision.

4.1.6 Sensor/Instrument Measurement Geometry

Not applicable.

4.1.7 Manufacturer of Sensor/Instrument

RGA-3 Chromatograph

Trace Analytical

3517-A Edison Way

Menlo Park, CA 94025

IL- 1700 Radiometer

International Light, Inc.

17 Graf Road

Newburyport, MA 01950

Temperature Probe

Cole-Palmer Instrument Company

7425 North Oak Park Avenue

Niles, IL 60714

TDR

Tektronix, Inc.

Beaverton, OR

Page 4
4.2 Calibration

4.2.1 Specifications

Instrumentswereconfiguredandmaintainedaccordingto manufacturers'specificationsnotedin

the instruction manuals and were calibrated routinely according to standards.

4.2.1.1 Tolerance

The precision of fluxes for the trace gas measurements, computed from three replicates, is expected

to be 15% for CO2 and CH4, and 5-10% for CO. The precision is judged by the standard deviation of

the three measurements.

4.2.2 Frequency of Calibration

Calibration was performed immediately before measuring each day's samples. Correlation

coefficients of 0.99 or better were achieved in all cases. A secondary standard of near atmospheric

CO2, CH4, or CO concentration was injected periodically during analysis to ensure that no

instrumental drift occurred.

4.2.3 Other Calibration Information

CH4 and CO2 concentrations were calculated by comparing sample peak areas obtained with a

Shimadzu CR501 dual chalmel integrator to those resulting from repeated analysis of two CH4

standards and two CO2 standards. The CH4 standards contained 0.90-ppm and 2.05-ppm CI_, and

the CO2 standards contained 356.1-ppm and 397.4-ppm CO2. The standard gases were supplied by

the BOREAS project and calibrated by the Atmospheric Environment Service (AES) of Canada. Based

on 10 to 15 daily measurements of these standards, the precision of analysis (standard deviation

divided by the mean value expressed in percentage) was 0.7 _+0.3% for CFLI and 1.7 _+0.4% for

CO2. For CO calibration, a standard curve was generated each day by injecting calibrated volumes of a

9.5 _+0.14-ppm CO primary standard (National Institute of Standards and Technology, Gaithersburg,

MD).

5. Data Acquisition Methods

A static chamber technique [such as that described by Whalen and Reeburgh, 1988] was used to

estimate soil/atmosphere CH4 and CO2 exchange. The chamber consists of a permanently deployed

circular aluminum collar, with a water seal and skirt, and an opaque lid. The collars were N10, 25, or

30 cm deep in areas with significant moss, lichen, or burned vegetation cover, and N5 cm deep in areas

in which the vegetation had burned to the mineral layer. The lid is constructed of aluminum and is

equipped with a septum for syringe sampling and a small hole to equalize pressure. The total enclosed

area is 0.036 m2, and the enclosed volume is about 8.7 liters.

CH4 and CO2 flux samples were collected at 5-minute intervals over the course of 20 minutes in

60-mL polypropylene syringes with siliconized polypropylene plungers and nylon three-way

stopcocks. Syringes were stored in the dark at ambient temperature until analysis. Concentration

determinations were made using a Carle AGC GC equipped with a TCD and a FID. Gas samples were

introduced to the GC via a 10-port gas sampling valve plumbed for the simultaneous filling of two

sample loops and then injection into two columns. Separation of CH4 and CO2 was accomplished with

1/8-inch outer diameter (o.d.) stainless steel Hayesep-D (3 m for the FID side and 2 m for the TCD

side) analytical columns.

Soil-atmosphere CO exchange was measured using transparent, static soil chambers. These

chambers consisted of two parts: a semipermanent base installed into the ground and a removable glass

cover that isolated the atmosphere immediately above the base. The aluminum chamber bases consisted

of an open-ended, 0.215-m i.d. cylinder (the skirt). The bottom edge of the skirt was beveled to aid

insertion into the soil. Skirt lengths were either 0.5 or 0.10 m, depending upon the thickness of the

organic layer above the mineral soil. A concentric trough (_30 cm i.d. and 4 cm deep) was welded to

Page 5
thetopof thechamber.Thistrough,whenfilled with water,providedanairtightsealwith thetop.

Threeorfour 0.5-cm-o.d.x 10-cm-longaluminumspikeswereattachedsymmetricallyaroundthe

circumferenceof theskirtto providea secureinstallation.TheglasschambertopswereKimax

(Kimble,Vineland,NJ)borosilicatejars (25cm deep,-24 cm i.d., volume-12 liters).Thesejars

weretransparentto visible(400-700nm)andUV-A (315-400nm) light,butfilteredoutapartof

UV-B (280-315nm)radiation.Two 1/4-inchholesweredrilled in thesideof eachglassjar with a

90-degreeradialdisplacementand-15 cmverticaldisplacementbetweeneachhole.Theseholeswere

usedassamplingandventports.Theholeswerepluggedwith smallcorks,andneedleswereinserted

throughthecorks.Theventconsistedof a 1-inch-long,22-gaugeneedle,andthesamplingport

consistedof a4- to 6-inch-long,18-gaugeneedle.Bothneedleswereleft opento theatmosphere

duringsampling,therebypreventingpressuredifferentialsduringexperiments.

Soil-atmosphereCOexchangewasmeasuredin thefollowing manner.First,thetroughof the

chamberbasewasfilled with enoughwaterto ensureanairtight sealwith thechambertop.Then,the

topwasquickly butgentlyplacedin thetroughandagassampleof-20 mL wasremovedfrom the

chamber.Additionalsampleswerecollected(usuallyat7-minuteintervals)for atotalof atleastfour

samples.Foreachsample,thesyringewasconnectedto thesamplingneedleandpumpedthreetimes

to ensureawell-mixedchamber.Approximately20mL of samplewascollected,andthesyringe

stopcockwasclosed.Thebackof thesyringebarrelwassealedwith aminimumamountof distilled

waterandstoredin aplasticziplockbagoniceuntil analysis.Theall-glasssyringes(Popper& Sons,

New HydePark,NY) werefitted withgas-tightTeflonstopcocks(AlltechAssociates,Deerfield,IL)

andencasedin blackheat-shrinktubingto keeptheircontentsdark.Samplingwasconductedbetween

thehoursof 1000and1500localtimewith theexceptionof twodiurnalstudies.

Air andsoil temperatures(atadepthof 10cmfor CO2andCH4; 1.0 cm for CO) were measured

with a thermocouple probe. Volumetric soil moisture content was measured with a TDR as described

by Topp et al. [1984]. Total solar irradiance was measured during the CO flux measurements with the

light probe placed close to the environmental chamber.

6. Observations

6.1 Data Notes

None given.

6.2 Field Notes

Date

July 19

July 20

July 21

July 22

July 23

July 24

July 25

July 26

July 27

July 28

July 29

July 30

July 31

Aug 1

Aug 2

Aug 3

Aug 4

Aug 5

Location

Lab

Gillam Road: 94GR, CGR

Gillam Road: 92GR, 87GR

Leaf Rapids Road: 89JP,

Leaf Rapids Road: 89FR,

Gillam Road: 94GR

Gillam Road: 94GR, 87GR

Gillam Road: CGR, 92GR

Gillam Road: CGR, 92GR

Tower Beaver Pond

CJP

CFR

Gillam Road: 94GR, 92GR

Gillam Road: CGR, 87GR

Leaf Rapids Rd: 89JP, CJP

Gillam Road: 92GR

Gillam Road: 92GR

Activity

Arrive Thompson

Set up laboratory

CH4 CO2,

CH4 CO2,

CH4 CO2,

CH4 CO2,

CH4 CO2, CO

CH4 CO2, CO

CH4 CO2, CO

CH4 CO2, CO

CO flux from

Off

Off

CH4, CO2, CO

CH4, CO2, CO

CH4, CO2, CO

CH4, CO2, CO

CH4, CO2, CO

CO fluxes

CO fluxes

CO fluxes

CO fluxes

fluxes;

fluxes

fluxes

fluxes;

pond

fluxes

fluxes

fluxes

fluxes;

fluxes;

process studies

process studies

diurnal

diurnal continued

Page 6
Aug

Aug

Aug

Aug

Aug

Aug

6

7

8

14

15

16

Aug 17

Aug 18

Aug 19

Aug 20

Aug 21

Aug 22

Aug 23

Aug 24

Aug 25

Aug 26

Aug 27

Aug 28

Aug 29

Aug 30

Aug 31

Sept 1

Sept 2

Sept 2

Gillam Road: CGR, 87GR

Gillam Road: 94GR, 92GR

Lab

Arrive Thompson

Lab

Gillam Road: CGR, 94GR

94GR #6 dug up by animal;.

Gillam Road: 92GR, 87GR

Gillam Road: CGR

Gillam Road: CGR

Leaf Rapids Road: 89FR, CFR

Leaf Rapids Road: 89JP, CJP

Gillam Road: CGR, 92GR

Gillam Road: 87GR, 94GR

Gillam Road: NGRC, CGR

87GR

Gillam Road: CGR, 92GR,

87GR, 94GR, NCGR

Gillam Road: CGR, 92GR

Gillam Road: 87GR, 94GR

Gillam Road: 92GR, 94GR,

87GR

Lab; Leaf Rapids Road:

89FR, CFR

Gillam Road: 92GR, 94GR

Lab

Leave Thompson

CH4, CO2, CO fluxes

CH4, CO2, CO fluxes

Shut down equipment; ship soil samples

Set up lab

CH4, CO2, CO fluxes

re-install in another location about i0 ft

toward Thompson

CH4, CO2, CO fluxes

CH4, CO2, CO fluxes; diurnal

CH4, CO2, CO fluxes; diurnal continued

Off

CH4, CO2, CO fluxes

CH4, CO2, CO fluxes

Four chamber bases missing from 89 Jack Pine

site - presumed stolen; remove remaining

bases to prevent additional theft and remove

some chambers from CJP site for placement in

new control site on Gillam Road

CH4, CO2, CO fluxes

CH4, CO2, CO fluxes

CH4, CO2, CO fluxes; SF6 at 87GR

Place three chamber bases in New Gillam Road

Control (two medium skirt, one deep skirt)

Simul. rain event at CGR, 92GR, 87GR,

94GR; CH4, CO2, CO fluxes at NCGR

Off

CH4, CO2, CO fluxes

CH4, CO2, CO fluxes

SF6 diffusion studies

SF6 analysis; SF6 diffusion

at 89FR and CFR

SF6 diffusion studies

Pack and ship equipment

and CH4/CO2

7. Data Description

7.1 Spatial Characteristics

7.1.1 Spatial Coverage

Measurements were performed on upland black spruce (Picea mariana) and jack pine (Pinus banksiana)

forest sites in the vicinity of the BOREAS NSA, which is located near Thompson, Manitoba. The North

American Datum of 1983 (NAD83) latitude and longitude coordinates of Thompson, Manitoba are 55 ° 91'

N, 98 ° 42' W. Four black spruce sites, three burned and one control, were selected about 100 km northeast

of Thompson, Manitoba. The sites were located at 56 ° 09' N, 96 ° 44' W; 56 ° 08' N, 96 ° 42' W. All four

black spruce sites, which were located within 5 km of each other, were exposed to very similar climatic

conditions. The jack pine burn site was located in a large burn site (115,643 ha; summer 1989) on Hwy

391 near Leaf Rapids, Manitoba, 140 km west-northwest of Thompson, Manitoba. A jack pine stand

located 133 km west-northwest of Thompson, unburned for at least 80 years, served as the control for the

jack pine burn site. At each site, the environmental chambers were used to measure fluxes within an area

that was approximately 10,000 m2.

Page 7
7.1.2 Spatial Coverage Map

A map showing site locations is included.

7.1.3 Spatial Resolution

The environmental chambers used to measure soil fluxes of CO2, CO, and CH4 covered an area about

0.036 m2. Flux measurements for CO2, CO, and CH4 were at six locations within the site.

7.1.4 Projection

Not applicable.

7.1.5 Grid Description

Not applicable.

7.2 Temporal Characteristics

7.2.1 Temporal Coverage

The environmental chambers were used to measure soil surface fluxes between June and September

1994. Data were obtained during Intensive Field Campaign (IFC)-1, IFC-2, August 1994, and the first

week of IFC-3.

7.2.2 Temporal Coverage Map

See section 6.2 Field Notes.

7.2.3 Temporal Resolution

Individual flux measurements generally were made over a period of 20 to 30 minutes. Flux experiments

were routinely conducted between the hours of 1000 and 1600. local time with selected diurnal studies

during August 1994 conducted throughout the day and night.

The flux and ancillary data at a given black spruce site were obtained with a sampling frequency of 2-3

days during the periods noted in Section 7.2.1. Data at the jack pine sites were obtained on a weekly basis.

7.3 Data Characteristics

7.3.1 Parameter/Variable

The parameters contained in the data files on the CD-ROM are:

Column Name

SITE NAME

SUB SITE

DATE OBS

TIME OBS

STATION ID

CO2 FLUX

CH4 FLUX

CO FLUX

AIR TEMP

SOIL TEMP ICM

SOIL TEMP 10CM

CALC DOWN SHORTWAVE RAD

REVISION DATE

CRTFCN CODE

Page 8
7.3.2 Variable Description/Definition

The descriptions of the parameters contained in the data files on the CD-ROM are:

Column Name Description

SITE NAME

SUB SITE

DATE OBS

TIME OBS

STATION ID

CO2 FLUX

CH4 FLUX

CO FLUX

AIR TEMP

SOIL TEMP ICM

SOIL TEMP 10CM

CALC DOWN SHORTWAVE RAD

REVISION DATE

CRTFCN CODE

The identifier assigned to the site by BOREAS

Information System (BORIS) staff, in the format

SSS-TTT-CCCCC, where SSS identifies the portion

of the study area: NSA, SSA, REG, or TRN; TTT

identifies the cover type for the site (999 if

unknown); and CCCCC is the identifier for the

site (exactly what it means will vary with site

type).

The identifier assigned to the subsite by BORIS,

in the format GGGGG-IIIII, where GGGGG is the

group associated with the sub-site instrument

(e.g., HYD06 or STAFF), and IIIII is the

identifier for the subsite (often this will refer

to an instrument).

The date on which the data were collected.

The Greenwich Mean Time (GMT) when the data were

collected.

The station identifier from which the measurement

came.

Carbon dioxide flux.

Methane flux.

Carbon monoxide flux.

The measured air temperature.

Soil temperature at 1 cm depth.

Soil temperature at i0 cm depth.

Calculated total irradiance encompassing

wavelengths from 200-4200 nanometers.

The most recent date that the information in the

referenced data base table record was revised.

The BOREAS certification level of the data.

Examples are Checked by PI (CPI), Certified

by Group (CGR), Preliminary (PRE), and CPI

but questionable (CPI-???) .

7.3.3 Unit of Measurement

The measurement units for the parameters contained in the data files on the CD-ROM are:

Column Name Units

SITE NAME

SUB SITE

DATE OBS

TIME OBS

STATION ID

CO2 FLUX

CH4 FLUX

CO FLUX

AIR TEMP

SOIL TEMP ICM

[none]

[none]

[DD-MON-YY]

[HHMM GMT]

[none]

[micromoles] [meter-2] [second-l]

[micromoles] [meter-2] [second-l]

[micromoles] [meter-2] [second-l]

[degrees Celsius]

[degrees Celsius]

Page 9
SOIL TEMP 10CM [degrees Celsius]

CALC DOWN SHORTWAVE RAD [Watts] [meter^-2]

REVISION DATE [DD-MON-YY]

CRTFCN CODE [none]

7.3.4 Data Source

The sources of the parameter values contained in the data files on the CD-ROM are:

Column Name Data Source

SITE NAME

SUB SITE

DATE OBS

TIME OBS

STATION ID

CO2 FLUX

CH4 FLUX

CO FLUX

AIR TEMP

SOIL TEMP ICM

SOIL TEMP 10CM

CALC DOWN SHORTWAVE RAD

REVISION DATE

CRTFCN CODE

Assigned by BORIS

Assigned by BORIS

Investigator

Investigator

Investigator

RGA-3 Chromatograph

RGA-3 Chromatograph

RGA-3 Chromatograph

Thermometer

Temperature probe

Temperature probe

IL-1700 Radiometer

Assigned by BORIS

Assigned by BORIS

7.3.5 Data Range

The following table gives information about the parameter values found in the data files on the

CD-ROM.

Minimum Maximum Missng Unrel Below Data

Data Data Data Data Detect Not

Column Name Value Value Value Value Limit Cllctd

SITE NAME NSA-9BS-T05GR NSA-9JP-T5391 None None None None

SUB SITE TGB05-F87GR TGB05-FXCJP None None None None

DATE OBS 08-MAR-94 17-OCT-96 None None None None

TIME OBS 0 2300 None None None None

STATION ID 1 6 None None None None

CO2 FLUX 0.0281 4.47 -999 -888 None Blank

CH4 FLUX -11.5625 0.00083 -999 -888 None Blank

CO FLUX -0.0262 0.057 None -888 None Blank

AIR TEMP -0.6 91 -999 None None Blank

SOIL TEMP ICM -0.2 58.2 -999 None None Blank

SOIL TEMP 10CM -0.3 20 -999 None None Blank

CALC DOWN SHORTWAVE RAD 21 967 -999 None None Blank

REVISION DATE 26-SEP-97 26-SEP-97 None None None None

CRTFCN CODE CPI CPI None None None None

Minimum Data Value -- The minimum value found in the column.

Maximum Data Value -- The maximum value found in the column.

Missng Data Value -- The value that indicates missing data. This is used to

indicate that an attempt was made to determine the

parameter value, but the attempt was unsuccessful.

Unrel Data Value -- The value that indicates unreliable data. This is used

to indicate that an attempt was made to determine the

Page 10
Below Detect Limit

Data Not Cllctd

parameter value, but the analysis personnel deemed the

value to be unreliable.

The value, that indicates parameter values below the

instruments detection limits. This is used to

indicate that an attempt was made to determine the

parameter value, but the analysis personnel determined

that the parameter value was below the detection

limit of the instrumentation.

This value indicates that no attempt was made to

determine the parameter value. This usually

indicates that BORIS staff combined several similar but

not identical data sets into the same data base table

but this particular science team did not

measure that parameter.

Blank -- Indicates that blank spaces are used to denote that type of value.

N/A -- Indicates that the value is not applicable to the respective column.

None -- Indicates that no values of that sort were found in the column.

7.4 Sample Data Record

The following are wrapped versions of data records from a sample data file on the CD-ROM.

SITE NAME,SUB SITE,DATE OBS,TIME OBS,STATION ID,CO2 FLUX,CH4 FLUX,CO FLUX,AIR TEMP,

SOIL TEMP ICM, SOIL TEMP 10CM, DOWN SHORTWAVE RAD,REVISION DATE,CRTFCN CODE

'NSA-9JP-T5391', 'TGB05-F89JP',08-MAR-94,1615, '5', .994,-.0013773,,19.7,,15.0,,

26-SEP-97, 'CPI'

'NSA-9JP-T5391', 'TGB05-F89JP',08-MAR-94,1615, '6', .745,-.0013889,,19.7,,15.0,,

26-SEP-97, 'CPI'

8. Data Organization

8.1 Data Granularity

The smallest unit of data tracked by BORIS was the flux measurement from a given site on a given day.

8.2 Data Format(s)

The Compact Disk-Read-Only Memory (CD-ROM) files contain American Standard Code for

Information Interchange (ASCII) numerical and character fields of varying length separated by commas.

The character fields are enclosed with single apostrophe marks. There are no spaces between the fields.

Each data file on the CD-ROM has four header lines of Hyper-Text Markup Language (HTML) code at

the top. When viewed with a Web browser, this code displays header information (data set title, location,

date, acknowledgments, etc.) and a series of HTML links to associated data files and related data sets. Line

5 of each data file is a list of the column names, and line 6 and following lines contain the actual data.

9. Data Manipulations

9.1 Formulae

9.1.1 Derivation Techniques and Algorithms

None.

Page 11
9.2 Data Processing Sequence

9.2.1 Processing Steps

Gas samples were collected from the environmental chambers at the field sites, transferred to the

laboratory, and analyzed by gas chromatography. The fluxes were then calculated from measured

concentrations of the gases vs. time.

9.2.2 Processing Changes

None given.

9.3 Calculations

9.3.1 Special Corrections/Adjustments

For each chamber experiment, the concentration of CO within the chamber was plotted as a function of

time after sealing the chamber top over the base. These plots showed three different patterns: (1) linear

changes with time, (2) first-order decay with time, and (3) initial linear increase followed by a diminished

rate of increase, often yielding a steady state. Concentration vs. time plots were initially plotted to determine

the curve shape, and the data analysis was determined based on curve shape. Data were analyzed by

performing linear regression (slope = CO exchange rate), by performing log-linear regression (slope =

first-order rate constant), or by determining the initial slope.

9.3.2 Calculated Variables

Fluxes of C02 and CH4 were calculated by linear regression of the measured concentrations of samples

(typically five) collected during each chamber deployment. CO fluxes were calculated as described in

Section 9.3.1.

9.4 Graphs and Plots

Data were plotted using Lotus Freelance, Lotus 123, and Quattro Pro.

10. Errors

10.1 Sources of Error

A few flux measurements were rejected because of various problems such as loss of one or more time

points, contaminated or leaky syringes, GC problems, or disturbance of the site during sampling. These

problems usually became apparent when either: (1) the initial concentration was not close to the ambient

concentration, or (2) the correlation coefficient of the linear regression was not significant at the 90%

confidence level (1-2= 0.810 for n = 4; 1-2= 0.648 for n = 5).

10.2 Quality Assessment

Based on the actual performance of the flux measurement system during this study, the minimum

detectable flux of CH4 is estimated to be about 0.3 mg CH4-C/mZ/d, and the minimum detectable flux of

CO2 to be 0.1 g CO2-C/m2/d.

10.2.1 Data Validation by Source

Calibrations and instrumentation ranges were checked, and data were checked for values that were not

in expected ranges.

10.2.2 Confidence Level/Accuracy Judgment

For all of the C02 and CH4 data analyzed with regressions, data sets were rejected if the correlation

coefficient of the linear regression was not significant at the 90% confidence level (r2 = 0.810 for n = 4; r2

= 0.648 for n = 5). For CO measurements that exhibited decreasing CO concentrations vs. time, the data

sets were rejected if the correlation coefficient of the linear regression of log concentration vs. time was not

significant at the 90% confidence level.

Page 12
10.2.3 Measurement Error for Parameters

Typically, replicate measurements of the same gas sample are within 10% RSD for CO2, CH4, and CO.

10.2.4 Additional Quality Assessments

Multiple comparison procedures were performed with the software package SigmaStat (Jandel

Scientific, San Rafael, CA) to test for statistically significant differences in gas fluxes and volumetric water

content among sets of samples grouped by site or by date within a given site. Each data group was tested

for normality (Kolmogorov-Smirnov test) and equal variance (Levene median test) with the SigmaStat

package. For comparisons of data groups with normal distributions and equal variances, a One Way

Analysis of Variance (ANOVA) was performed to test for differences in mean values of the different

groups. If significant differences in the means were found, then a Student-Newman-Keuls (SNK) All

Pairwise Multiple Comparisons Procedure was performed to identify specific differences between groups.

For comparisons of data groups in which normality and/or equal variance conditions were not met, a

Kruskal-Wallis ANOVA on ranks was performed. If the differences in the median values among these

groups were found to be significant, then specific differences between groups were tested for by the

Dunnas Method of All Pairwise Multiple Comparisons. Mean ranks were calculated from the results of the

ranking procedures associated with the nonparametric tests and are presented to indicate trends in the

various parameters. Probability and significance levels were set to 0.05 in the SigmaStat package unless

otherwise specified. Simple and multiple linear regression procedures were also performed with the

SigmaStat package. Zar [ 1984] and Glanz and Slinker [1990] give details of the statistical tests performed.

10.2.5 Data Verification by Data Center

Data were examined for general consistency and clarity.

11. Notes

11.1 Limitations of the Data

There are no known limitations. However, the user should be aware that there are few other data sets

available on soil trace gas fluxes in sites that have been recently burned. Therefore, there is no way at this

point to judge the representativeness of this data set.

11.2 Known Problems with the Data

None.

11.3 Usage Guidance

None given.

11.4 Other Relevant Information

The procedures and data obtained in this study are monitored by several mechanisms:

• Formal methods of comparisons. Several comparisons have been made under field and laboratory

conditions that have substantiated that the instruments used in this study provide reliable

measurements of trace gases.

• Informal comparisons among investigators. Comparisons of the data obtained in this study at

unburned control sites with flux data obtained using environmental chambers or towers at other

BOREAS NSA sites indicate that these fluxes are in the same range as those observed elsewhere in

this region. This favorable comparison suggests that these results are representative of this region.

• Review in the scientific literature. These and other BOREAS results were published in a Special

Issue of the Journal of Geophysical Research so that they will be available to the international

scientific community. In these publications, the methods were justified to peer referees. These

justifications are based on other published methods and tests, which are described in previous

papers.

Page 13
12. Application of the Data Set

These data along with other trace gas measurements from chambers, towers, and aircraft can be used to

characterize and model the fluxes of trace gases from the various boreal forest ecosystems.

None.

13. Future Modifications and Plans

14. Software

14.1 Software Description

These results are being used to improve the CENTURY soils model so that it can be used to evaluate

carbon storage and trace gas fluxes in boreal forest soils.

14.2 Software Access

The SigmaStat, Lotus, and other commercial software packages are available from their specific

commercial developers.

The CENTURY software will be available from Dr. Dennis Ojima and Dr. William Parton, NREL,

Colorado State University, Ft. Collins, CO. The data also likely will be used to improve and test other

models that simulate the biosphere-atmosphere exchange of trace gases.

15. Data Access

The CO2, CH4, and CO chamber flux data over the NSA are available from the Earth Observing System

Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active

Archive Center (DAAC).

15.1 Contact Information

For BOREAS data and documentation please contact:

ORNL DAAC User Services

Oak Ridge National Laboratory

P.O. Box 2008 MS-6407

Oak Ridge, TN 37831-6407

Phone: (423) 241-3952

Fax: (423) 574-4665

E-mail: ornldaac@ornl.gov or ornl@eos.nasa.gov

15.2 Data Center Identification

Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory

(ORNL) Distributed Active Archive Center (DAAC) for Biogeochemical Dynamics

http://www-eosdis.ornl.gov/.

15.3 Procedures for Obtaining Data

Users may obtain data directly through the ORNL DAAC online search and order system

[http://www-eosdis.ornl.gov/] and the anonymous FTP site [ftp://www-eosdis.ornl.gov/data/] or by

contacting User Services by electronic mail, telephone, fax, letter, or personal visit using the contact

information in Section 15.1.

Page 14
15.4 Data Center Status/Plans

The ORNL DAAC is the primary source for BOREAS field measurement, image, GIS, and hardcopy

data products. The BOREAS CD-ROM and data referenced or listed in inventories on the CD-ROM are

available from the ORNL DAAC.

16. Output Products and Availability

16.1 Tape Products

None.

16.2 Film Products

None.

16.3 Other Products

These data are available on the BOREAS CD-ROM series.

17. References

17.1 Platform/Sensor/Instrument/Data Processing Documentation

None.

17.2 Journal Articles and Study Reports

Burke, R.A., R.G. Zepp, M.A. Tart, W.L. Miller, and B.J. Stocks. 1997. Effect of fire on

soil-atmosphere exchange of methane and carbon dioxide in Canadian boreal forest sites. Journal of

Geophysical Research 102(D24): 29,289-29,300.

Crill, P.M. 1991. Seasonal patterns of methane uptake and carbon dioxide release by a temperate woodland

soil. Global Biogeochemical Cycles 5: 319-334.

Glanz, S.A. and B.K. Slinker. 1990. Primer of Applied Regression and Analysis of Variance.

McGraw-Hill, New York, 777 pp.

Hutchinson, G.L., and G.P. Livingston. 1993. Use of chamber systems to measure trace gas fluxes, in

Agricultural Ecosystem Effects on Trace Gases and Global Climate Change. ASA Special Publication No.

55. American Society of Agronomy, Madison, WI, pp. 63-78.

Newcomer, J., D. Landis, S. Conrad, S. Curd, K. Huemmrich, D. Knapp, A. Morrell, J. Nickeson, A.

Papagno, D. Rinker, R. Strub, T. Twine, F. Hall, and P. Sellers, eds. 2000. Collected Data of The Boreal

Ecosystem-Atmosphere Study. NASA. CD-ROM.

Sellers, P. and F. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1994-3.0,

NASA BOREAS Report (EXPLAN 94).

Sellers, P. and F. Hall. 1996. Boreal Ecosystem-Atmosphere Study: Experiment Plan. Version 1996-2.0,

NASA BOREAS Report (EXPLAN 96).

Sellers, P., F. Hall, and K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere Study: 1994 Operations.

NASA BOREAS Report (OPS DOC 94).

Sellers, P., F. Hall, and K.F. Huemmrich. 1997. Boreal Ecosystem-Atmosphere Study: 1996 Operations.

NASA BOREAS Report (OPS DOC 96).

Page 15
Sellers,P.,F. Hall, H. Margolis,B. Kelly, D. Baldocchi,G. denHartog,J.Cihlar, M.G. Ryan,B.

Goodison,P.Crill, K.J.RansomD. Lettenmaier,andD.E. Wickland. 1995.Theboreal

ecosystem-atmospherestudy(BOREAS):anoverviewandearlyresultsfrom the 1994field year.Bulletin

of theAmericanMeteorologicalSociety.76(9):1549-1577.

Sellers,P.J.,F.G.Hall, R.D.Kelly, A. Black, D. Baldocchi,J. Berry, M. Ryan,K.J. Ranson,P.M.

Crill, D.P.Lettenmaier,H. Margolis,J. Cihlar,J.Newcomer,D. Fitzjarrald,P.G.Jarvis,S.T.Gower,

D. Halliwell, D. Williams, B. Goodison,D.E.Wickland,andF.E.Guertin.1997.BOREASin 1997:

ExperimentOverview,ScientificResultsandFutureDirections.Journalof GeophysicalResearch

102(D24):28,731-28,770.

Topp,G.C.,J.L.Davis,W.G.Bailey, andW.D. Zebchuk.1984.Themeasurementof soil watercontent

usingaportableTDR handprobe.Can.J.Soil Sci.,313-321.

Whalen,S.C.andW.S.Reeburgh.1988.A methaneflux time seriesfor tundraenvironments.Global

Biogeochem.Cycles,2, 399-409.

Zar, J.H.BiostatisticalAnalysis,3rdEd. 1996.Prentice-Hall,EnglewoodCliffs, NJ, 718pp.

Zepp,R.G., W.L. Miller, M.A. Tart, R.A. Burke,andB.J. Stocks.1997.Soil-atmospherefluxesof

carbonmonoxideduringearlystagesof postfiresuccessioninuplandCanadianborealforests.Journalof

GeophysicalResearch102(D24):29,301-29,311.

17.3 Archive/DBMS Usage Documentation

None.

None given.

18. Glossary of Terms

19. List of Acronyms

AES - Atmospheric Environment Services

ANOVA - One Way Analysis of Variance

ASCII - American Standard Code for Information

BOREAS - BOReal Ecosystem-Atmosphere Study

BORIS - BOREAS Information System

CD-ROM - Compact Disk-Read-Only Memory

CGR - Certified by Group

CPI - Checked by PI

CPI-??? - CPI but questionable

DAAC - Distributed Active Archive Center

EOS - Earth Observing System

EOSDIS - EOS Data and Information System

EPA - Environmental Protection Agency

FID - Flame Ionization Detector

GC - Gas Chromatograph

GMT - Greenwich Mean Time

GSFC - Goddard Space Flight Center

HTML - HyperText Markup Language

IFC - Intensive Field Campaign

NASA - National Aeronautics and Space

Interchange

Administration

Page 16
NSA

PANP

PI

PRE

ORNL

SNK

SOM

SSA

TCD

TDR

TGB

URL

UV

- Northern Study Area

- Prince Albert National Park

- Principal Investigator

- Preliminary

- Oak Ridge National Laboratory

- Student-Newman-Keuls

- Soil Organic Matter

- Southern Study Area

- Thermal conductivity Detector

- Time Domain Reflectometer

- Trace Gas Biogeochemistry

- Uniform Resource Locator

- Ultraviolet

20. Document Information

20.1 Document Revision Date

Written: 04-Jun- 1997

Last Updated: 27-May- 1999

20.2 Document Review Date(s)

BORIS Review: 06-Oct- 1997

Science Review:

20.3 Document ID

20.4 Citation

When using these data, please contact one of the people listed in Section 2.3 as well as citing relevant

papers in Section 17.2:

If using data from the BOREAS CD-ROM series, also reference the data as:

Zepp R.G. and R.A. Burke, "Trace Gas Exchange in the Boreal Forest Biome: Effects of Fire and

Beaver Activity." In Collected Data of The Boreal Ecosystem-Atmosphere Study. Eds. J. Newcomer, D.

Landis, S. Conrad, S. Curd, K. Huemmrich, D. Knapp, A. Morrell, J. Nickeson, A. Papagno, D. Rinker,

R. Strub, T. Twine, F. Hall, and P. Sellers. CD-ROM. NASA, 2000.

Also, cite the BOREAS CD-ROM set as:

Newcomer, J., D. Landis, S. Conrad, S. Curd, K. Huemmrich, D. Knapp, A. Morrell, J. Nickeson,

A. Papagno, D. Rinker, R. Strub, T. Twine, F. Hall, and P. Sellers, eds. Collected Data of The Boreal

Ecosystem-Atmosphere Study. NASA. CD-ROM. NASA, 2000.

20.5 Document Curator

20.6 Document URL

Page 17
REPORT DOCUMENTATION PAGE FormApproved

OMB No. 0704-0188

Public reporting burden for this collection of informationis estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources,

gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this

collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson

Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503.

1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED

November 2000 Technical Memorandum

4. TITLE AND SUBTITLE 5. FUNDING NUMBERS

Technical Report Series on the Boreal Ecosystem-Atmosphere Study (BOREAS)

BOREAS TGB-5 CO 2, CH4, and CO Chamber Flux Data over the NSA 923

6. AUTHOR(S) RTOP: 923-462-33-01

Roger Burke and Richard Zepp

Forrest G. Hall and Sara K. Conrad, Editors

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS (ES)

Goddard Space Flight Center

Greenbelt, Maryland 20771

9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS (ES)

National Aeronautics and Space Administration

Washington, DC 20546-0001

8. PEFORMING ORGANIZATION

REPORT NUMBER

2000-03136-0

10. SPONSORING / MONITORING

AGENCY REPORT NUMBER

TM--2000-209891

Vol. 229

11. SUPPLEMENTARY NOTES

R. Burke and R. Zepp: U.S. Environmental Protection Agency, Athens, Georgia;

Sara K. Conrad: Raytheon ITSS

12a. DISTRIBUTION / AVAILABILITY STATEMENT

Unclassifie_Unlimited

Subject Category: 43

Report available from the NASA Center for AeroSpace Information,

7121 Standard Drive, Hanover, MD 21076-1320. (301) 621-0390.

12b. DISTRIBUTION CODE

13. ABSTRACT (Maximum 200 words)

The BOREAS TGB-5 team collected a variety of trace gas concentration and flux measurements at

several NSA sites. This data set contains carbon dioxide (CO2), methane (CH4), and carbon monoxide

(CO) chamber flux measurements conducted in 1994 at upland forest sites that experienced standreplacement fires. These measurements were acquired to understand the impact of fires on soil biogeochemistry and related changes in trace gas exchange in boreal forest soils. Relevant ancillary data,

including data concerning the soil temperature, solar irradiance, and information from nearby unburned control sites, are included to provide a basis for modeling the regional impacts of fire and

climate changes on trace gas biogeochemistry. The data are provided in tabular ASCII files.

14. SUBJECT TERMS

BOREAS, trace gas biogeochemistry.

17. SECURITY CLASSIFICATION

OF REPORT

Unclassified

NSN 7540-01-280-5500

18. SECURITY CLASSIFICATION

OF THIS PAGE

Unclassified

19. SECURITY CLASSIFICATION

OF ABSTRACT

Unclassified

15. NUMBER OF PAGES

1'7

16. PRICE CODE

20. LIMITATION OF ABSTRACT

UL

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