Forests, fungi, and small mammals: the impact of fire and forest thinning on truffle production and...

Post on 18-Dec-2015

217 views 2 download

Tags:

transcript

Forests, fungi, and small mammals: the impact of fire and

forest thinning on truffle production and consumption

Marc Meyer and Malcolm NorthMarc Meyer and Malcolm NorthUSFS PSW Research StationUSFS PSW Research Station

Sierra Nevada Research CenterSierra Nevada Research CenterDavis, CaliforniaDavis, California

Douglas KeltDouglas KeltDepartment of Wildlife, Fish, & Department of Wildlife, Fish, &

Conservation BiologyConservation BiologyUniversity of California, DavisUniversity of California, Davis

?

Study Questions:

What effect does burning and What effect does burning and mechanical thinning have on the mechanical thinning have on the forest ecosystem?forest ecosystem?

Study Questions:

What effect does burning and What effect does burning and mechanical thinning have on the mechanical thinning have on the forest ecosystem?forest ecosystem?

Does combining treatments (fire + Does combining treatments (fire + thinning) have a greater impact thinning) have a greater impact than burning alone?than burning alone?

ectomycorrhizal fungi

small mammals

fruiting bodies (truffles)provide a major food

source

ectomycorrhizal fungi

small mammals

fruiting bodies (truffles)provide a major food

source

dispersal offungal spores

ectomycorrhizal fungi

small mammals

fruiting bodies (truffles)provide a major food

source

dispersal offungal spores

foresttrees

TeakettleExperimental

Forest

Experimental forestboundary

Stream

Teakettle Experimental Forest

200 m

•18 plots total

•Plots 4 ha in area

•Plots represent replicate stands

Teakettle Experimental Design(n = 3 per treatment; 6 treatments total)

No Burn Burn

No Thin

Light Thin(understory)

Heavy Thin (overstory)

light thin only light thin & burn

heavy thin only heavy thin & burn

control burn only

Truffle sampling (2002-2003):

9 grid points per plot in 3 x 3 grid (50 m 9 grid points per plot in 3 x 3 grid (50 m spacing, 50 m buffer)spacing, 50 m buffer)

truffle sampling (4 mtruffle sampling (4 m22 plots) at all grid plots) at all grid points - 100 mpoints - 100 m22 per plot per season per plot per season

2 seasons of sampling for 2 years2 seasons of sampling for 2 years Frequency, species richness, and biomass of Frequency, species richness, and biomass of

trufflestruffles

Truffle consumption Lodgepole chipmunks (Lodgepole chipmunks (Tamias speciosusTamias speciosus) )

sampled June-August 2002-2003 at truffle sampled June-August 2002-2003 at truffle grid pointsgrid points

microhistological analysis of chipmunk microhistological analysis of chipmunk dietsdiets frequency of truffle consumptionfrequency of truffle consumption generic richness of truffles in dietgeneric richness of truffles in diet

Truffles

MANOVA results for effect of thinning & burning on truffle production

Dependent variable

Factor F df P

MANOVA BurnThinB × T

6.5824.0180.848

3,226,446,44

0.0020.0030.068

Truffle frequency 2002-03Vertical bars denote 0.95 confidence intervals

No thin Light thin Heavy thin-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

Lo

g1

0(%

truffle

freq

ue

ncy)

No burn

Truffle frequency 2002-03Vertical bars denote 0.95 confidence intervals

No thin Light thin Heavy thin-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

Lo

g10

(% tru

ffle fre

qu

en

cy)

Burn No burn

Truffle biomass 2002-03Vertical bars denote 0.95 confidence intervals

No thin Light thin Heavy thin-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

Lo

g1

0(tru

ffle b

iom

ass, g

/ha

)

No burn

Truffle biomass 2002-03Vertical bars denote 0.95 confidence intervals

No thin Light thin Heavy thin-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

Lo

g1

0(tru

ffle b

iom

ass, g

/ha

)

Burn No burn

Truffle consumption

MANOVA results for effect of burning & thinning on truffle consumption

Dependent variable

Factor F df P

MANOVA BurnThinB × T

15.6534.7860.570

2,214,422,21

0.0010.0030.686

2002-03 Diet frequency for T. speciosusVertical bars denote 0.95 confidence intervals

No thin Light thin Heavy thin30

40

50

60

70

80

90

100

% fre

qu

en

cy of tru

ffles in

die

t

No burn

2002-03 Diet frequency for T. speciosusVertical bars denote 0.95 confidence intervals

No thin Light thin Heavy thin30

40

50

60

70

80

90

100

% fre

qu

en

cy of tru

ffles in

die

t

Burn No burn

2002-03 Diet data for T. speciosus

Vertical bars denote 0.95 confidence intervals

no thin light thin heavy thin0.0

0.1

0.2

0.3

0.4

0.5

0.6

log

10(#

of tru

ffle g

en

era

in d

iet)

NO BURN

2002-03 Diet data for T. speciosus

Vertical bars denote 0.95 confidence intervals

no thin light thin heavy thin0.0

0.1

0.2

0.3

0.4

0.5

0.6

log

10(#

of tru

ffle g

en

era

in d

iet)

BURN NO BURN

MANOVA comparisons in burned + thinned vs. burned only

Dependent variable F df P

Truffle production

Truffle consumption

4.990

9.069

3,22

2,21

0.009

0.001

Conclusions: Significant reduction in truffle production Significant reduction in truffle production

& consumption following burning or & consumption following burning or thinningthinning

Conclusions: Significant reduction in truffle production Significant reduction in truffle production

& consumption following burning or & consumption following burning or thinningthinning

Plots pre-treated with thinning prior to Plots pre-treated with thinning prior to burning had lower truffle production & burning had lower truffle production & consumption than plots burned onlyconsumption than plots burned only

Management implications:

Current forest management policy in the Current forest management policy in the Sierra Nevada (i.e. Sierra Nevada Forest Sierra Nevada (i.e. Sierra Nevada Forest Plan Amendment 2001) uses combined thin Plan Amendment 2001) uses combined thin & burn treatments for fuel reduction& burn treatments for fuel reduction

Management implications:

Current forest management policy in the Current forest management policy in the Sierra Nevada (i.e. Sierra Nevada Forest Sierra Nevada (i.e. Sierra Nevada Forest Plan Amendment 2001) uses combined thin Plan Amendment 2001) uses combined thin & burn treatments for fuel reduction& burn treatments for fuel reduction These combined treatments have a These combined treatments have a

substantial impact on truffle production substantial impact on truffle production & consumption& consumption

Management implications:

Current forest management policy in the Current forest management policy in the Sierra Nevada (i.e. Sierra Nevada Forest Sierra Nevada (i.e. Sierra Nevada Forest Plan Amendment 2001) uses combined thin Plan Amendment 2001) uses combined thin & burn treatments for fuel reduction& burn treatments for fuel reduction These combined treatments have a substantial These combined treatments have a substantial

impact on truffle production & consumptionimpact on truffle production & consumption

Long-term data neededLong-term data needed

Acknowledgments

USFS PSW Research Lab USFS Forest Health Technology Enterprise

Grant, Joint Fire Science Program Grant, NIGMS IMSD Fellowship, UC Graduate Opportunity Fellowships

Sarah Reed, Blake Meneken, Jamie Burke, Kerry Byrne