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Table 1 List of adjustment functions used in recent methods to link models of different resolutions

From: Linking individual-tree and whole-stand models for forest growth and yield prediction

Citation

Method

Eq. no.

Adjustment function1/

Qin and Cao ([2006])

Proportional yield

1

p ˜ 2 , i = p ^ 2 i s N ^ 2 ∑ j p ^ 2 j

  

2

d ˜ 2 i 2 = d ^ 2 i 2 s B ^ 2 / K ∑ j p ^ 2 j d ^ 2 j 2

  

3

h ˜ 2 i = h ^ 2 i s V ^ 2 − a N ^ 2 b ∑ j p ^ 2 j d ^ 2 j 2 h ^ 2 j

 

Proportional growth

4

p ˜ 2 i = p ^ 2 i p ^ 2 i + m p 1 − p ^ 2 i

  

5

d ˜ 2 i 2 = d 1 i 2 + s B ^ 2 / K − ∑ j p ˜ 2 j d 1 j 2 ∑ j p ˜ 2 j d ^ 2 j 2 − d 1 j 2 d ^ 2 i 2 − d 1 i 2

  

6

h ˜ 2 i = h 1 i + s V ^ 2 − a N ^ 2 − b ∑ j p ˜ 2 j d ˜ 2 j 2 h 1 j b ∑ j p ˜ 2 j d ˜ 2 j 2 h ^ 2 j − h 1 i h ^ 2 i − h 1 i

 

Constrained least squares

7

p ˜ 2 i = p ^ 2 i + s N ^ 2 − ∑ p ^ 2 j /n

  

8

d ˜ 2 i 2 = d ^ 2 j 2 − p ˜ 2 i ∑ j p ˜ 2 j d ^ 2 j 2 − s B ^ 2 / K ∑ j p ˜ 2 j 2

  

9

h ˜ 2 i = h ^ 2 i − p ˜ 2 i d ˜ 2 i 2 ∑ j p ˜ 2 j d ˜ 2 j 2 h ^ 2 j + s a N ^ 2 − V ^ 2 / b ∑ j p ˜ 2 j 2 d ˜ 2 j 4

 

Coefficient adjustment

10

p ˜ 2 i = p 1 i / 1 + exp α 0 + α 1 H 1 + α 2 m p d 1 i / D q 1

  

11

d ˜ 2 i = d 1 i 1 + exp β 0 + β 1 ln B 1 + β 2 A 1 + β 3 ln H 1 + β 4 m d d 1 i D q 1 + β 5 ln h 1 i

  

12

h ˜ 2 i = h 1 i 1 + exp γ 0 + γ 1 ln B 1 + γ 2 A 1 + γ 3 ln H 1 + γ 4 m h d 1 i D q 1 + γ 5 h 1 i H 1 + γ 6 ln d 1 i

Cao ([2006])

Disaggregation

13

p ˜ 2 i = p ^ 2 i m p

  

14

d ˜ 2 i 2 = d 1 i 2 + s B ^ 2 / K − ∑ j p ˜ 2 j d 1 j 2 ∑ j p ˜ 2 j d ^ 2 j 2 − d 1 j 2 d ^ 2 i 2 − d 1 i 2

 

Constraining individual-tree model with diameter-class attributes

15

p ^ 2 i = 1 / 1 + exp α 0 + α 1 N 1 + α 2 B 1 + α 3 d 1 i n ^ 2 , k = ∑ i = 1 n 1 , k p ^ 2 i

16

d ^ 2 i = d 1 i + β 1 A 2 A 1 β 2 H 1 β 3 B 1 β 4 d 1 β 5 b ^ 2 , k = K ∑ i = 1 n 1 , k p ^ 2 i d ^ 2 i 2

 

Constraining individual-tree model with stand attributes

17

p ^ 2 i = 1 / 1 + exp α 0 + α 1 N 1 + α 2 B 1 + α 3 d 1 i N ^ 2 = ∑ i p ^ 2 i / s

18

d ^ 2 i = d 1 i + β 1 A 2 A 1 β 2 H 1 β 3 B 1 β 4 d 1 β 5 B ^ 2 = K s ∑ i p ^ 2 i d ^ 2 i 2

Yue et al. ([2008])

Combined estimator

19

B ˜ 2 =w B ^ 2 T + 1 - w B ^ 2 S ,

where w is selected to minimize the variance of B ˜ 2 .

Zhang et al. ([2010])

Combined estimator

20

B ˜ 2 = w 1 B ^ 2 T + w 2 B ^ 2 S + w 3 B ^ 2 D ,

where w k is selected to minimize ∑ B 2 − B ˜ 2 2 , and ∑ k 3 w k =1.

Cao ([2010])

1

21

p ˜ 2 i = p ^ 2 i m

Tree survival

2

22

p ˜ 2 i = p ^ 2 i p ^ 2 i + m p 1 − p ^ 2 i

 

3

23

p ˜ 2 i =1/ 1 + exp m p α 0 + α 3 d 1 i

 

4

24

p ˜ 2 i =1/ 1 + exp α 0 + α 1 N 1 + α 2 B 1 + m p d 1 i

 

5

25

p ˜ 2 i = p ^ 2 i + s N ^ 2 − ∑ j p ^ 2 j s N 1 − ∑ j p ^ 2 j 1 − p ^ 2 i

Cao ([2010])

1

26

d ^ 2 i = d 1 i + m d d 1 β 5

Tree diameter growth

2

27

d ^ 2 i = d 1 i + β 1 A 2 A 1 β 2 H 1 β 3 B 1 β 4 d 1 m d

 

3

28

d ˜ 2 i 2 = d 1 i 2 + s B ^ 2 / K − ∑ j p ˜ 2 j d 1 j 2 ∑ j p ˜ 2 j d ^ 2 j 2 − d 1 j 2 d ^ 2 i 2 − d 1 i 2

  1. 1/ Notation:
  2. A 1 = stand age at the beginning of the growth period.
  3. A 2 = stand age at the end of the growth period.
  4. H 1 = dominant height at age A 1.
  5. N 1 = number of trees per ha at age A 1.
  6. N ^ 2 = predicted number of trees per ha at age A 2.
  7. B 1 = stand basal area at age A 1.
  8. B ^ 2 = predicted stand basal area at age A 2.
  9. B ^ 2 D = predicted stand basal area at age A 2 from a diameter distribution model.
  10. B ^ 2 S = predicted stand basal area at age A 2 from a whole-stand model.
  11. B ^ 2 T = predicted stand basal area at age A 2 from an individual-tree model.
  12. B ˜ 2 = combined estimator for stand basal area at age A 2.
  13. V ^ 2 = predicted volume per ha at age A 2, Dq 1 = quadratic mean diameter at age A 1.
  14. a and b = parameters of the individual tree volume equation, v i =a+b d i 2 h i .
  15. v i , d i , and h i  = tree volume, dbh, and total height of tree i, respectively.
  16. s = plot size in ha.
  17. K = π/40 000 = constant to convert diameter in cm to area in m2.
  18. n = number of trees in the plot.
  19. d 1i or d 1j  = dbh of tree i or j at age A 1.
  20. d ^ 2 i or d ^ 2 j = predicted dbh of tree i or j at the end of the growth period.
  21. d ˜ 2 i = adjusted dbh of tree i at the end of the growth period.
  22. h 1i  = total height of tree i at age A 1.
  23. h ^ 2 i or h ^ 2 j = predicted total height of tree i or j at the end of the growth period.
  24. h ˜ 2 i = adjusted total height of tree i at the end of the growth period.
  25. p 1i  = survival probability of tree i at age A 1.
  26. p ^ 2 i or p ^ 2 j = predicted survival probability of tree i or j at the end of the growth period.
  27. p ˜ 2 i or p ˜ 2 j = adjusted survival probability of tree i or j at the end of the growth period.
  28. α 0 … α 3 = parameters of the tree survival equation.
  29. β 0 … β 5 = parameters of the tree diameter growth equation.
  30. γ 0 … γ 6 = parameters of the tree height growth equation.
  31. n 1,k  = number of trees of the k th diameter class at age A 1.
  32. n ^ 2 , k = predicted number of trees of the k th diameter class at age A 2.
  33. b ^ 2 , k = predicted basal area of the k th diameter class at age A 2, and m p , m d , and m h  = adjustment coefficients to be iteratively solved to ensure that the resulting number of trees per ha, stand basal area, and stand volume, respectively, match those produced by the whole-stand model.