validation of nbsm techniques within anf.pptresultsresults--correlation between cbi correlation...
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Validation of National Burn SeverityValidation of National Burn SeverityValidation of National Burn Severity Validation of National Burn Severity Mapping Project Techniques Within Mapping Project Techniques Within
A i iA i ithe Apalachicola National Forestthe Apalachicola National Forest
Joshua J. Picotte
Dr. Kevin Robertson
Project OverviewProject Overview
BackgroundBackgroundBackgroundBackgroundProject QuestionsProject QuestionsResultsResultsResultsResultsProblemsProblemsConclusionsConclusionsConclusionsConclusions
BackgroundBackground--Burn Severity and Burn Severity and Joint Fires Science Program (JFSP)Joint Fires Science Program (JFSP)
Burn SeverityBurn Severity--ecosystem ecosystem h d l dh d l dchange and landscape change and landscape
changechangeSystem developed in 1996 System developed in 1996 b C l K d N tb C l K d N tby Carl Key and Nate by Carl Key and Nate Benson Benson Started in the Western Started in the Western U it d St tU it d St t
Key and Benson 1995
United StatesUnited StatesInitial Fires AssessedInitial Fires Assessed--1994 1994 Glacier National Park FiresGlacier National Park FiresNeeds more work in EastNeeds more work in EastNeeds more work in EastNeeds more work in East
JFSP was formed in 1998 to JFSP was formed in 1998 to provide support for fuel and provide support for fuel and fire management programsfire management programsg p gg p g
Key and Benson 1995
BackgroundBackground--Composite Burn Index Composite Burn Index (CBI) and Normalized Burn Ratio(CBI) and Normalized Burn Ratio(CBI) and Normalized Burn Ratio (CBI) and Normalized Burn Ratio
(NBR)(NBR)i f b ii f b iNBRNBR--Remote sensing of burn severityRemote sensing of burn severity
Landsat bands RLandsat bands R44 and Rand R77
NBR = (RNBR = (R44--RR77)/ (R)/ (R44+R+R77))dNBR=NBR prefire-NBR postfire
CBICBI--Ground measure of burn severityGround measure of burn severity30 m plot30 m plotpp
CBI should validate NBR valuesCBI should validate NBR values
BackgroundBackground--deltaNormalized Burn deltaNormalized Burn Ratio (dNBR)Ratio (dNBR)Ratio (dNBR)Ratio (dNBR)
dNBR: Change in reflectance
30m
30m
30m
between pre-fire (1 year pre-fire) and post-fire NBR values
ddNBR=NBRprefire-NBRpostfire
Weighted dNBR = Average of plot t d (N 5)
100 99UnburneddNBRSeverity
center and corners (N=5)
439 659Moderate High269 - 439Low-Moderate99 - 269Low-100 - 99Unburned
659 - 1300High439 - 659Moderate-High
BackgroundBackground--Composite Burn Composite Burn Index (CBI)Index (CBI)Index (CBI)Index (CBI)
Burn Index: 0Burn Index: 0--33Burn Index: 0Burn Index: 0 3300--UnburnedUnburned33--Severe BurnSevere Burn
Five StrataFive Strata44--5 Ratings Factors5 Ratings FactorsAveragedAveraged
CBI ScoreCBI ScoreAverage of Five StrataAverage of Five Strata
BackgroundBackground--Apalachicola National Apalachicola National Forest (ANF)Forest (ANF)Forest (ANF)Forest (ANF)
Gulf of Mexico
Unburned2006 Dormant dNBR
Low Severity
Low-Moderate Severity
Moderate-High Severity
High Severityg y
²0 13,716 27,4326,858 Meters ²
BackgroundBackground--Habitats Within ANFHabitats Within ANF
A.A. Sandhill PinelandSandhill PinelandA.
•• Turkey OakTurkey Oak•• WiregrassWiregrass•• Bracken FernBracken Fern•• LongLong--Leaf PineLeaf Pine
B.B. Flatwood PinelandFlatwood PinelandPalmettoPalmetto
B.
•• PalmettoPalmetto•• LongLong--Leaf/Slash PineLeaf/Slash Pine
C.C. Depression SwampDepression SwampCC•• CypressCypress
•• TitiTiti•• Pond PinePond Pine
C.
Project QuestionsProject Questions
1.1. Does this system adequately describe burn severity Does this system adequately describe burn severity y q y yy q y ywith the South East ecosystems?with the South East ecosystems?
2.2. How long after a fire can burn perimeters be How long after a fire can burn perimeters be l dl dremotely sensed?remotely sensed?
3.3. Are there differences in the effectiveness of using Are there differences in the effectiveness of using CBI and dNBR to categorize burn severity in theCBI and dNBR to categorize burn severity in theCBI and dNBR to categorize burn severity in the CBI and dNBR to categorize burn severity in the three community types of the ANF? three community types of the ANF?
4.4. What are the appropriate ranges dNBR for given What are the appropriate ranges dNBR for given W e e pp op e ges d o g veW e e pp op e ges d o g veburn severity categories?burn severity categories?
5.5. What problems arise in assessing burn severity?What problems arise in assessing burn severity?
ResultsResults--Sandhill Burn SeveritySandhill Burn Severity
25² 0 671 1341335 Meters
15
20
Area146.7Unburned
AcresSeverity
10
Perc
ent F
ire
0.225High
9.675Moderate-High
318.6Low-Moderate
617.625Low
0
5
dNBR
946.125Total Burned
1092.825Total
ResultsResults--Flatwood Burn SeverityFlatwood Burn Severity
Wet Flatwoods, Initial Assessment
18
20²0 16,002 32,0048,001 Meters
AcresSeverity 12
14
16
18
e Ar
ea
1312.2Moderate-High
3442.725Low-Moderate
5673.825Low
9850.5Unburned
4
6
8
10
Perc
ent F
ire
10597.73Total Burned
20448.23Total
168.975High
0
2
4
dNBR
Sandhill
ResultsResults--Correlation Between CBI Correlation Between CBI and dNBRand dNBROverall
2
2.5
Sandhill
2
2.5
and dNBRand dNBR
1
1.5
CB
I
1
1.5
CB
I
0
0.5
-100 0 100 200 300 400 500 600 700dNBR Weighted
0
0.5
0 50 100 150 200 250 300 350 400 450 500
dNBR Weighted
Flatwoods
2
2.5
1
1.5
2
CB
I
<0 0010 767Flatwoods
0.9130.000Sandhills
0.0050.125Overall
P>FrR2
0
0.5
-100 0 100 200 300 400 500 600 700
dNBR Weighted
<0.0010.767Flatwoods
ResultsResults--Correlations between CBI Correlations between CBI and dNBR Within Substratesand dNBR Within Substrates
0.7330.002Substrates
P>FrR2
Overall
and dNBR Within Substratesand dNBR Within Substrates
0.0790.032Upper Canopy Trees
0.1740.040Subcanopy Trees
<0.0010.1871m < Vegetation < 5m
<0.0010.212Vegetation < 1m
0.7330.002Substrates
0.0790.032Upper Canopy Trees
2
Sandhills2
Flatwoods
0 390 00S
0.2780.0381m < Vegetation < 5m
0.5560.011Vegetation < 1m
0.3120.033Substrates
P>FrR2
0010 09S
<.0010.4991m < Vegetation < 5m
<.0010.372Vegetation < 1m
0.0020.304Substrates
P>FrR2
0.3280.032Upper Canopy Trees
0.7390.005Subcanopy Trees
<.0010.516Upper Canopy Trees
<.0010.509Subcanopy Trees
Burn Severity Change DetectionBurn Severity Change Detection--WaterWaterWater Water
²2006 Dormant dNBR
0 823 1646411 Meters² 0 100 20150 Meters²Unburned
Low Severity
Low-Moderate Severity
Moderate-High SeverityModerate High Severity
High Severity
Actual Pond BoundaryLakes and Ponds
Problematic detection of Low Burn Problematic detection of Low Burn SeveritySeverity
2006 Dormant dNBR
A.
B.
SeveritySeverity
Unburned
Low Severity
Low-Moderate Severity
Moderate-High Severity
! 30m PlotsHigh Severity
C.
dNBRCBIPlot
C.
89.61.27C.59.21.23B.
11.23A.
² 0 610 1,020305 Meters²
ConclusionsConclusionsConclusionsConclusions
Successful in high fire frequency communitiesSuccessful in high fire frequency communitiesSuccessful in high fire frequency communitiesSuccessful in high fire frequency communitiesExtrapolation to other communities within the EastExtrapolation to other communities within the East
U f l t f b it iU f l t f b it iUseful system for burn monitoringUseful system for burn monitoringSense perimeter months following the burnSense perimeter months following the burn
Season of remoteSeason of remote--sensing (dNBR) may be sensing (dNBR) may be limitedlimitedUseful in assessing the “success” of burn Useful in assessing the “success” of burn management plansmanagement plansg pg p
AcknowledgementsAcknowledgements
Nate Benson Nate Benson Jason DrakeJason DrakeLeigh LentileLeigh LentileCaroline Noble Caroline Noble Joe NobleJoe NobleDon OhlenDon OhlenKathy MaroisKathy MaroisDavid PrintissDavid PrintissDavid Printiss David Printiss Greg Titus Greg Titus Eugene WatkinsEugene WatkinsEugene WatkinsEugene Watkins