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Fire Project Update:Fire Project Update:
Mass and nutrient loss of cattail communities in WCA 2A in response to
prescribed firesprescribed fires Quarterly Communications Meeting on the
Long Term Plan for Achieving Water Quality GoalsLong-Term Plan for Achieving Water Quality Goalsfor Everglades Protection Area Tributary Basins
September 29 2009September 29, 2009
ShiLi Miao (PI)Cassondra Thomas
Amy Farrell
Management objectiveA h th lti l f fi l t thAssess whether multiple surface fires accelerate the recovery of the nutrient-enriched areas now dominated by cattails in WCA 2Ay
Research objectivesj• Determine ecological effects of multiple surface fires on critical wetland ecosystem structure, function, and processes in nutrient-enriched areas
• Examine natural recovery pattern in WCA 2A
Conceptual model for Fire ProjectConceptual model for Fire Project
1. Release and Return
P1
1.2.3.
Release and ReturnSurface WaterSoil
Ash Ash
P1.4. Vegetation
Water Flow PP P
P
PP
2.
4.
Species Species other other than than
cattailcattail
PP
P
Soil PSoil P
Competition for Nutrients
PPDecompositionDecomposition
3.Competition for Nutrients
SedimentSediment
ObjectivesObjectives
• Quantify mass and nutrient loss and• Quantify mass and nutrient loss and return
• Examine factors that affect mass and nutrient loss and return
• Assess ash chemistry and its impacts t liton water quality
Fire Project Design
WCA-2A
Fire Project Design
WCA 2AWaterDepth
Date Type (cm)Highly P-enriched
(1000 -1200 mg/kg)
Moderately P-enrichedH2H1
Highly enrichedJuly 2006 Prescribed 10July 2008 Prescribed 43
Moderately P enriched(600 -1000 mg/kg)
Reference(< 600 mg/kg)
Rs
M2M1 Moderately enriched
February 2006 Wildfire 19August 2008 Prescribed 32
RcRs
Fire ImplementationFire Implementation
A Bi d N t i tAverage Biomass and Nutrient Loss
800
1000
7 008.009.00
7357.3
g/m
2 )
600
800
g/m
2 )
4 005.006.007.00735
Loss
(g
400
Loss
(g
0.75
1.004.00
351
0
200
0 00
0.25
0.500.4
Mass Carbon0
Nitrogen Phosphorus0.00
Average Biomass and NutrientAverage Biomass and Nutrient Loss
40
50
g/m2 40
50
ss (%
)
30
40
ss (%
)
30
40
Los
10
20 Los
20
M C b0
10
Ni Ph h0
10
Mass Carbon Nitrogen Phosphorus
Biomass & Nutrient Loss atBiomass & Nutrient Loss at Different Habitat & Burns
Habitat Fire # Nutrient loss (%)Mass Carbon Nitrogen P
Highly-enriched 1 62 62 62 502 44 43 58 49
Moderately-enriched 1 49 62 63 412 28 25 28 30
Highly-enriched plot post-fire, 2006
Combusted mass•62% of total mass
Nutrients released m-2
• 585 g C 0 7 P• 78 % of dead litter
layer• 24 % of live leaves
• 0.7 g P• 11 g N
Highly-enriched plot post-fire, 2008
Combusted mass•44% total mass
63 % f d d litt
Nutrients released m-2
• 379 g C• 63 % of dead litter
layer• 10 % of live leaves
• 0.6 g P• 10 g N
post-fire - February 21, 20061 dayModerately-enriched plot post-fire, 2006
Combusted mass•49% total mass
59 % f d d litt
Nutrients released m-2
• 424 g C • 59 % of dead litter layer
• 19 % of live leaves
g C• 0.1 g P• 10 g N
Moderately-enriched plot post-fire 2008
Combusted mass•28% total mass
Nutrients released m-2
• 195 g C28% total mass• 33 % of dead litter
layer• 17 % of live leaves
195 g C• 0.2 g P• 3 g N
Mass Loss and Pre-Fire MassMass Loss and Pre Fire Masss
(%)
100y = 0.02X + 4.02 Highly enriched 1st Fire
Moderately enriched 1st Fire
ss L
oss
80
yr2 = 0.28p = 0.05
Moderately enriched 1st FireHighly enriched 2nd FireModerately enriched 2nd Fire
nd m
as
40
60
vegr
oun
20
40
0 500 1000 1500 2000 2500 3000
Abo
v
0
Pre-fire Aboveground mass (g/m2)
Mass Loss and Water DepthMass Loss and Water Depths
(%)
80
100 y = -0.854x + 63.59r2 = 0.27
p = 0.056
mas
s Lo
s
60
80
egro
und
m
40
Abo
ve
0
20 Highly-enriched 1st Fire Moderately-enriched 1st FireHighly-enriched 2nd FireModerately-enriched 2nd Fire
Water Depth (cm)0 10 20 30 40 50
Mass Loss and Temperaturep
(%)
80
100
120
Cattail
Mas
s Lo
ss
20
40
60
80
SawgrassRegression line95% Confidence intervalHighly enriched 1st FireModerately enriched 1st FireHighly enriched 2nd Fire
0
oss
(%)
60
80
100
120
g yModerately enriched 2nd Fire
TN L
o
0
20
40
60
120
C L
oss
(%)
40
60
80
100
Temperature (oC)0 100 200 300 400 500 600
T
0
20
Mass Loss and SpeciesMass Loss and SpeciesCattail Sawgrass
AirTotal C
(351 g/m2)(40%)
Total N(7.3 g/m2)
(47%) Particulate P(0.36 g/m2)
Aboveground Mass(1681 g/m2)
C N P & Metals
(40%)( g )
(40%)
C,N,P & Metals(810 g C/m2, 14.0 g N/m2, 0.8 g
P/m2)A. Release
All %s in A. are based on pre-mass
Ash Collection DesignAsh Collection Design
Nutrient Return to the SystemNutrient Return to the System
AshLeaf fragmentsg1.4%1.4%
Sediment
Water
Sediment
Ash Return to the SystemAsh Return to the System
Ash return % pre-fire % burnedAsh return % pre-fire % burned
Mass 0.6 1.4
Ash TN 0.5 0.9
Ash TC 0.4 1.0
Ash TP 4.0 8.9
Air
Ash(10.6 g/m2)
(1.4%)
B. Return
Water
MetalsTN
(0.06 g/m2)(0.9%)
TC(3.4 g/m2)
(1.0%)
TP(0.03 g/m2)
(8.9%)
PO4(0.9 mg/m2)
NH4(0.5 mg/m2)
NO3(0.1 mg/m2)
Soil( g )
(0.25%)(0 5 g/ )
(0.007%)(0 g/ )
(0.001%)
All %s in B are based on burned mass or nutrient content
Ash Chemistry with Varying Temperatureg/
g re
sidu
e)
500
600
700
mg/
g re
sidu
e)
30
40
al C
arbo
n (m
200
300
400
al N
itrog
en (m
10
20
Temperature (οC)150 250 350 450 550As
h To
ta
0
100
Temperature (οC)150 250 350 450 550As
h To
ta
0
mg/
g re
sidu
e)
12
14
16
Cattail LiveCattail DeadSawgrass LiveSawgrass Dead ho
spho
rus
(m
4
6
8
10
Sawgrass Dead
Temperature (οC)
150 250 350 450 550
Ash
Tota
l P
0
2
Surface Water pH Response to Ash Additionp p
8.6
pH
8.2
8.4
8.6Highly enriched 1st Fire Highly enriched 2nd Fire Moderately enriched 2nd Fire
face
wat
er p
7 6
7.8
8.0
Surf
7.2
7.4
7.6
Time 06:00 10:00 14:00 18:00 22:00
7.0
Ash Deposition and Water Depth onAsh Deposition and Water Depth on SWTP
AirTotal C
(351 g/m2)(40%)
Total N(7.3 g/m2)
(47%) Particulate P(0.36 g/m2)
Aboveground Mass(1681 g/m2)
C N P & Metals
(40%)( g )
(40%)
C,N,P & Metals(810 g C/m2, 14.0 g N/m2, 0.8 g
P/m2)A. Release
Ash(10.6 g/m2)
(0.6%)
B. Return
Water
MetalsTN
(0.06 g/m2)(0.5%)
TC(3.4 g/m2)
(0.4%)
TP(0.03 g/m2)
(4.0%)
PO4(0.9 mg/m2)
NH4(0.5 mg/m2)
NO3(0.1 mg/m2)
Soil( g )
(0.1%)(0 5 g/ )
(0.004%)(0 g/ )
(0.001%)
All percentages are based on pre-fire mass or nutrient content
Major ConclusionsMajor Conclusions• Prescribed fires were an effective way to quickly remove nutrients as approximatelyquickly remove nutrients, as approximately 1% of N and C and < 8% of P of burned nutrients was returned as ash.nutrients was returned as ash.• Pre-fire mass and water depth at the time of fire were the main factors determining massfire were the main factors determining mass and nutrient loss.• Water depth and fire temperature both• Water depth and fire temperature both directly (release) and indirectly (ash effect on water quality) affected ecosystem q y) ynutrient concentration.
Management ImplicationsManagement Implications
• Two years were required for fuel loads to return for repeated fire but more time may be required for additional fires
A N l d d l t d
may be required for additional fires.
• As more N was released and less returned in ash than P, repeated fires can lead to a more N limited system and therefore caremore N-limited system, and therefore care must be taken when considering prescribed fires in N-limited systems.es ted syste s
Management ImplicationsManagement Implications• Water depth is a key management
id i i h l l b 10 dconsideration with levels between 10 and 40 cm resulting in successful surface firesfires.
• The lower end is good for maximizing nutrient lossut e t oss
• The upper end is good for minimizing water quality changes.
• High water levels also reduce fire temperature, creating ash with lower pH, TP p , g p ,and soluble P concentrations.
CardoTBE Scheda EcologicalBEM S tSFWMD
AcknowledgementsCardoTBECassondra ThomasChris EdelsteinDean Monette
Scheda Ecological AssociatesErik SindhojLili CarpenterJ if Zi
BEM SystemsSusan CarstennWendy SoteraElsa Krauss
SFWMDRobert JohnsonBen Gu
Dean MonetteAmy FarrellDavid CoxChristina Stylianos
Jennifer ZimmermanJosh CreasserManuel Tapia
yAndy SteinerDan Pisut Birkitt
Environmental ServicesServicesHongjun Chen Damien CondoDan Salembier
Project Publications• Miao and Carstenn 2006. A new direction for large-scale experimental design and analysis. Frontiers in Ecology and the Environment 5: 227Frontiers in Ecology and the Environment 5: 227.
• Miao et al. 2008. Allometric relationships of field population of two clonal species with contrasting life histories, Cladium jamaicense and Typha domingensis. Aquatic Botany 88: 1-9.
• Gu et al. 2008. Effects of a prescribed fire on dissolved inorganic carbon dynamics in a nutrient-enriched Everglades wetland. Fundamental and Applied Limnology 171:263-272.
• Miao and Zou, 2009. Seasonal variation in seed bank composition and its interaction with nutrient enrichment in Everglades wetlands Aquatic Botany 90:157-164nutrient enrichment in Everglades wetlands. Aquatic Botany 90:157 164.
• Qian et al. 2009. Effects of burn temperature on ash nutrient forms and availability from cattail and sawgrass in the Florida Everglades. J. Environ. Qual. 38: 1-15.
Qi t l 2009 E ti ti f tfi t i t l i th Fl id E l d J E i Q l• Qian et al. 2009. Estimation of postfire nutrient loss in the Florida Everglades. J. Environ. Qual. 38: 1812-1820.
• Thomas et al. 2009. Environmental factors affecting temporal and spatial patterns of soil redox potential in Florida Everglades wetlands. Wetlands 29:1133-1145. p g
•Miao et al. 2009. Real World Ecology: Large-scale and Long-Term Studies and Methods. Springer
pdf request to “smiao@sfwmd.gov”
Thank You
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