Carbon Cycling in Native vs. Non-Native Dominated Rangeland Systems

Brian Wilsey - PI, Iowa State University

BNPPN, P, Soil C

FungiBacteriaArchaea

Experimental and Sampling Design

Map: John Madson

Part 2. ComparisonsPart 1. Experiment

x

Exotic Taxon Place of origin Native pair_________________________________________________________________________________________

C44 GRASSES

Bothriochloa ischaemum Tribe Andropogoneae Asia Schizachyrium scopariumCynodon dactylon Tribe Cynodonteae Africa Buchloe dactyloidesEragrostis curvula Tribe Eragrostideae Africa Sporobolus asperPanicum coloratum Genus Panicum Africa Panicum virgatumPaspalum dilatatum Tribe Paniceae South America Eriochloa sericeaSorghum halapense Tribe Andropogoneae Mediteranean Sorghastrum nutansPaspalum notatum Genus Paspalum Africa Paspalum floridanumDicanthium annulatum Tribe Andropogoneae Africa, Asia Andropogon gerardii

C33 GRASSES:

Festuca arundinacea Subfamily Pooideae Europe Elymus canadensisDactylus glomerata Subfamily Pooideae Europe Nasella luecotricha

FORBS:

Taraxacum officianale Asteraceae Europe Marshallia caespitosaCichorium intybus Asteraceae Eurasia Ratibida columniferaLeucanthemum vulgare Asteraceae Europe Vernonia baldwiniiRuellia britoniana Genus Ruellia Eurasia Ruellia humilisNepeta cataria Lamiaceae Eurasia Salvia azureaMarrubium vulgare Lamiaceae Eurasia Monarda fistulosa

LEGUMES:

Medicago sativa Subfamily Papilionoideae Eurasia Dalea purpureaTrifolium repens Subfamily Papilionoideae Europe Dalea candidumLotus corniculatus Fabaceae Eurasia Desmanthus illinoensisCoronilla varia Subfamily Papilionoideae Europe, Med. Astragalus canadensis________________________________________________________________________________________

Isbell, Wilsey, many others. 2015. Nature

t0 J08O08J09O09J10O10O11J12O12J13 J14O14J15O15J16

Num

ber o

f spe

cies

per

plo

t

0

2

4

6

8

10

Exotic - Irrig.Exotic - No Irr. Native - Irrig. Native - No Irr.

CV Not different!Origin,IrrigationP > 0.10

Exotic Native

Bio

mas

s C

V

0

10

20

30

40

50

60

IrrigatedNon - Irrigated

A

AA

A

Table 2. Species that dominated plots in 2012 (i.e., had highest pi, mean pi for exotics 0.78, range of 1 0.45-0.99, mean pi of 0.48 for natives, range 0.35-0.81 ) and their deviation from expected variance. 2 FG’s are C4G = C4 grasses, C3G = C3 grasses, C3F = C3 forbs. 3

_____________________________________________________________________________________4 Species FG no. plots mean(g) deviation t Ho = 0, P value 5

Exotic dominant species: 6

Panicum coloratum C4G 18 276.2 -0.263 -3.63 0.002 7

Sorghum halepense C4G 8 110.3 -0.324 -2.77 0.012 8

Eragrostis curvula C4G 3 120.5 -0.023 -0.29 0.777 9

Cynodon dactylon C4G 2 12.5 -0.846 -4.93 < 0.001 10

Bothriochloa ischaemum C4G 1 20.1 -0.197 -2.39 0.025 11

32 12

Native dominant species: 13

Eriochloa sericea C4G 13 117.7 -0.540 -9.87 < 0.001 14

Ratibida columnifera C4F 6 152.4 0.486 5.25 < 0.001 15

Elymus canadensis C3G 5 94.8 0.541 5.75 < 0.001 16

Sorghastrum nutans C4G 5 54.4 0.081 0.48 0.634 17

Nasella luecotricha C3G 2 57.0 0.406 3.29 0.005 18

Vernonia baldwinii C4F 1 18.8 0.357 2.89 0.012 19

32 20

_____________________________________________________________________________________ 21

22

23

2. Forage response to H2O treatment

Response to summer irrigation was larger in native communities Origin x Irrigation, F = 4.7, P = 0.03

Date

7-08 10-08 6-09 10-09 6-10 10-1010-11 6-12 10-12 6-13 10-13 6-14 10-14

Rat

io o

f irr

igat

ed/n

on-ir

rigat

ed

0.90

0.92

0.94

0.96

0.98

1.00

1.02

1.04

1.06

1.08

ExoticNative

Wilsey et al. (2014), Polley et al. (2014, 2016), Isbell et al. (2015)

2. Response to 2011 drought

Time (month, year)

J08O08J0

9O09J1

0O10O11J1

2O12J1

3O13J1

4O14J1

5

RU

E (g

m-2 m

m-1)

0.00

0.15

0.30

0.45

0.60

0.75

0.90

Natives Exotics

Natives Exotics

3. Root production and depth

b

fBNPP Beta Diversity

f BN

PP, B

eta,

and

div

ersi

ty

-2

-1

0

1

2

a

BNPP ANPP NPP

Pro

duct

ivity

(g m

-2)

0

300

600

900

1200

1500

1800

Natives Exotics

a

Ln-transformed soil depth (cm)

1 2 3 4

BN

PP

(g m

-2 c

m-1)

3

4

5

6

b

Ln-transformed soil depth (cm)

1 2 3 4

BN

PP

(g m

-2 c

m-1)

4

6

8

10

12

y=-1.36x+10.70r2=0.52, P=0.04

y=0.52x+3.20r2=0.63, P=0.02

Natives

Exotics

F 20

09N

=63

F 20

14N

=61

F 20

15N

=63

Native/Non-irrigated Native/Irrigated Exotic/Non-Irrigated Exotic/Irrigated

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 1 1 2 2 3 3 4 5 5 6 6 7 7 8 8 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 80%

10%20%30%40%50%60%70%80%90%

100%

1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 1 1 2 2 3 3 4 4 5 5 6 6 7 8 80%

10%20%30%40%50%60%70%80%90%

100%

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 80%

10%20%30%40%50%60%70%80%90%

100%

unknown phylum Ascomycota Basidiomycota Blastocladiomycota ChytridiomycotaFungi_phy_Incertae_sedis Glomeromycota Neocallimastigomycota Rozellomycota Zygomycota

perMANOVA and NMS (Bray Curtis distance matrix)

Source d.f F p ------------------------------------------------------origin 1 1.51 0.012irrig 1 1.17 0.168Interac. 1 0.82 0.854Residual 56

Source d.f. F p --------------------------------------------------------origin 1 1.62 0.017irrig 1 1.11 0.267Interac. 1 0.73 0.906Residual 48

Source d.f. F p ---------------------------------------------------------------origin 1 1.40 0.063irrig 1 0.92 0.570Interac. 1 1.63 0.017Residual 56

NativeExotic

NativeExotic

NativeExotic

2009 2014 2015

Fungal Pathogens 2014Source d.f. SS MS F p -----------------------------------------------------------------------------------origin 1 0.395 0.395 1.62 0.017000irrig 1 0.270 0.270 1.11 0.267000Interac. 1 0.177 0.178 0.73 0.906000Residual 48 11.67 0.243 Total 51 12.52

FDR_P E_mean N_mean taxonomy

0.03753 1.741935 55.2k__Fungi; p__Ascomycota;

c__Dothideomycetes; o__Pleosporales; f__Phaeosphaeriaceae; g__Stagonospora; s__

Genus Stagonospora – some species are plant pathogens

5. N mineralization (feedback)

Time 1 Time 2 Time 3

N m

iner

aliz

atio

n

0

1

2

3

4

5

6

7

Exotic Native

BA

BA

BA

Averaged across times, 24% higher in native plots than exotic (origin, P < 0.001)

6. Decomposition of litter, rootsRandom draws

Exotic Native

Mas

s pr

esen

t

0.90

0.92

0.94

0.96

0.98

Actual relative abundances

Exotic Native

Mas

s pr

esen

t

0.90

0.92

0.94

0.96

0.98

Origin x Abundance type, P < 0.001

Top (triangles) - Native

Bottom (circles) - Exotic

7. Mycorrhizal colonization

Species Pair

1 2 3 4 5 6 7 8 9 10 11

Med

ian

perc

ent c

olon

izat

ion

0

20

40

60

80

100

ExoticNative

P < 0.01, Means Exotic > Native

7. Soil Carbon accumulation

Polley, Fay, Gibson, Wilsey. 2016. Ecosystems

Comparative Studies:

• Native and Exotic grasslands across the tallgrass prairie region. N = 21 for each.

• Sample 25 locations per site (100 points), estimate % native/exotic, species diversity measures and ecosystem services.

Martin et al. (2014) Oecologia

Exotics greened up (reached 50% of peak NDVI)an average of 10 days earlier (p < 0.01)N

DV

I

Date

X XX X

Exotics senesced (dropped to 50% of peak)an average of 31 days later (p < 0.01)

ND

VI

Date

X XX X

Kaitlin Barber Ph.D. student project

BNPPN, P, Soil C

FungiBacteriaArchaea

Acknowledgements• Leanne Martin (Ph.D. student)• Kaitlin Barber (Ph.D. student)

• Xia Xu (postdoc)• Aleksandra Sielaff (postdoc)

• You (USDA – NIFA 2014-67003-22067)