Ecological Archives E095-197-A1

M. Luke McCormack, Thomas S. Adams, Erica A. H. Smithwick, David M. Eissenstat. 2014. Variability in root production, phenology, and turnover rate among 12 temperate tree species. Ecology 95:2224–2235. http://dx.doi.org/10.1890/13-1942.1

Appendix A. Background data and additional results for the heuristic model and observations of root dynamics in the Rock Springs Common Garden.

Table A1. Different lifespan-production scenarios used in heuristic model and resulting standing crop for each scenario. Numbers listed under each month represent the number of roots born (production) or present (standing crop) under each lifespan-production scenario. Monthly standing crop is calculated as the new root production of that month plus the standing crop of the previous month minus the roots determined to die in that month.

 

Lifespan
(days)

 

Jan

Feb

March

April

May

June

July

Aug

Sept

Oct

Nov

Dec

Concentrated

 

Production

0

0

2

10

15

30

20

10

7

5

1

0

91

Standing Crop

1

0

2

12

27

55

65

60

37

22

13

6

182

Standing Crop

23

13

8

13

27

57

77

87

92

87

73

43

365

Standing Crop

100

100

100

100

100

100

100

100

100

100

100

100

1215

Standing Crop

306

301

302

312

327

357

375

375

367

342

323

313

3650

Standing Crop

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

Distributed

 

Production

8

9

8

8

9

8

8

9

8

8

9

8

91

Standing Crop

25

25

25

25

25

25

25

25

25

25

25

25

182

Standing Crop

50

50

50

50

50

50

50

50

50

50

50

50

365

Standing Crop

100

100

100

100

100

100

100

100

100

100

100

100

1215

Standing Crop

333

334

333

333

334

333

333

334

333

333

334

333

3650

Standing Crop

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

Bi-modal, spring dominant

 

Production

1

1

5

10

15

23

15

8

14

5

2

1

91

Standing Crop

4

3

7

16

30

48

53

46

37

27

21

8

182

Standing Crop

34

25

15

20

33

52

66

75

85

80

67

48

365

Standing Crop

100

100

100

100

100

100

100

100

100

100

100

100

1215

Standing Crop

309

305

308

317

331

350

360

360

360

345

332

323

3650

Standing Crop

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

Bi-modal, equal peaks

 

Production

0

0

2

10

22

15

10

22

10

7

2

0

91

Standing Crop

2

   (1)

2

12

34

47

47

47

42

39

19

9

182

Standing Crop

41

19

11

14

34

49

59

81

89

86

66

51

365

Standing Crop

100

100

100

100

100

100

100

100

100

100

100

100

1215

Standing Crop

309

302

302

312

334

349

357

369

357

349

341

319

3650

Standing Crop

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

1000

 

Table A2. Coefficient of Variation (CV) for ƬAvgMax, ƬMin, and total number of roots produced across years 2008, 2009, and 2010 (N = 3).

 

Coefficient of Variation

Species

ƬAvg

ƬMax

ƬMin

Total Root Production

Acer negundo

31.3

23.8

56.4

51.5

Acer rubrum

28.9

16.6

90.0

54.3

Acer saccharum

23.3

16.6

41.2

14.2

Carya glabra

42.3

13.3

76.0

16.4

Juglans nigra

42.0

26.4

82.2

55.0

Liriodendron tulipifera

28.0

25.5

46.4

29.1

Pinus strobus

5.3

5.7

5.9

31.1

Pinus virginiana

29.1

26

45.9

61.5

Populus tremuloides

10.4

14.3

45.3

47.5

Quercus alba

36.7

36.2

43.9

35.5

Quercus rubra

35.7

17.7

103.3

56.8

Sassafras albidum

27.8

19.9

94.1

52.4

 

FigA1

Fig. A1. Weekly precipitation measured at a weather station near the Rock Spring Common Garden in central Pennsylvania, USA for years 2008, 2009, and 2010 (USDA NRCS, Site 2036 "Rock Springs", http://www.wcc.nrcs.usda.gov/nwcc/site?sitenum=2036&state=pa).


 

FigA2

Fig. A2. ƬMax, ƬAvg, and ƬMin (+SE) for 12 temperate tree species. Left y-axis indicates turnover rates for ƬMax and ƬAvg; right y-axis is for ƬMin. Significant differences in turnover rates between species according to Tukey HSD test indicated where species do not have the same letter (n = 3). Differences in ƬMin were not significant.


 

FigA3

Fig. A3. Least-squares regression (N = 12) between median fine root lifespan and root turnover rate (a) ƬMax (P = 0.0002), (b) ƬAvg (P = 0.0005), and (c) ƬMin (P = 0.02). Each point represents the mean turnover estimate (+SE, N = 3). Removal of the single point with the highest turnover rate and shortest lifespan (Populus tremuloides) reduces the strength of the relationship between lifespan and ƬMax and ƬAvg (P < 0.05, R² = 0.48 and 0.41 respectively) and cause the relationship to be nonsignificant for ƬMin.


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