integrated stand growth model (isgm)
DESCRIPTION
Integrated Stand Growth Model (ISGM). Hong LingXia 2006-06-28 The research institute of forest resource information techniques, Chinese Academy of Forestry (CAF). Abstract-1. Integrated Stand Growth Model (ISGM) is a group of correlated equations which include: - PowerPoint PPT PresentationTRANSCRIPT
Integrated Stand Growth Model (ISGM)
Hong LingXia 2006-06-28The research institute of forest resource information
techniques,
Chinese Academy of Forestry (CAF)
Abstract-1 Integrated Stand Growth Model (ISGM) is a
group of correlated equations which include:
1) basal area growth model
2) density index definition
3) basal area equation
4) Self-thinning model
5) dominant tree growth model
6) average tree growth model
7) form height model
8) stand volume model
Abstract-2
The statistical algorithm of nonlinear error-in-variable simultaneous equations is used to estimate the parameters of correlated equations to ensure that the parameter estimation of the group of correlated equations in ISGM is unbiased and the equations are compatible. ISGM can be used to simulate the even age stand growth and can out put different kinds of growth tables with different site index, stand density, thinning method and draw stand density control graph by ForStat (Chinese,CAF) or Capsis(English,CIRAD,Amap) software.
1.basal area growth model
b1,b2,b3,b4,b5 : parameters
G: total basal area
S: density index
age: the age of even-aged stand
352 ))]()10000
(exp(1[ 041bbb tage
SbLbG
2.density index definition
S: density index
N: number of trees per hectare
D: average diameter at breast height
β: parameter—self thinning rate
)D(NS
20
3.basal area equation
G: total basal area
N: number of trees per hectare
D: average diameter at breast height
)40000
(2 DNG
4.self-thinning model
a: a constant , for a given stand, the constant is decided by afforestation density (initial density )
sf: parameter--maxim density index
β: parameter--self thinning rate
γ: parameter
aD
N
sf )
20()(
5.dominant5.dominant tree growth model
b,c: parametersL: site indexage: the age of even-aged standbaseage: basic Site index age (in China,20)
)exp(baseage
b
age
bLUH
c)]agebexp([LUH 1
Schumacher
Richards
6.average tree growth model
a1,a2: parametersa1,a2: parameters
UH: dominantUH: dominant tree height
PH: average tree height
2
1
a
aUHPH
7.form height model
c1 ,c2 : parameters
PH: average tree height
PHPH
ccfH
)
2( 2
1
8.stand volume mode
fH: form height
G: total basal area
GfHM
ISGM model in ForStat software (Chinese)
Two main parts :
1. From the measurement data to calculate all the parameters in ISGM model .
2. To simulate the normal stand growth , thinning growth and draw the DensityControlGraph.
1-1.Measurement data
Site type Plot number age Number of trees per hectare
breast height diameter
Dominant tree height
Average tree height
volume
1-2.Measurement data requirement
1.For each site type must have several plot data, which include different age, different density and some maximum density plot .
2.For each plot must have some serial measurement data of different age.
3.If one plot have been thinned, before thinning and after thinning is treated as two plot ( have the same site type and different plot number ).
1-3.parameters calculation (ForStat)
1-4.out put window (ForStat)
parameters
2. To simulate the normal stand growth , thinning growth and draw the DensityControlGraph.
ForStat software ----Chinese
Capsis platform----Isgm model----English
Capsis platform--Isgm model--English
1.Normal growth simulation:
1)From plantation
2)From current situation
2.Thinning simulation:
Thinning procedure( selection )
3.DensityControlGraph
This kind of graph is originate in Japan.
2-1. Normal growth simulation--From plantation
give evolution selection:
Results—1.stand growth table
Results—2.dbh growth curve
Results—3.density index curve
Results—4.number of trees curve
Results—5.total basal area growth curve
Results—6.tree height growth curve
Results—7.volume growth curve
Results—8.volume growth rate
2-2. Normal growth simulation--From current
2-3. thinning simulation--From planted
2-4. DensityControlGraph
References: 1.Tang Shouzheng, Meng ZhaoHe, Meng FanRui.1994.A growth and self-thi
nning model for pure even-aged stands theory and applications. Forest Ecology and Management 70(1994): 67~73.
2.Tang Shouzheng, Meng FanRui, Meng ZhaoHe.1995.The impact of initial stand density and site index on maximum stand density index and self-thinning index in a stand self-thinning model. Forest Ecology and Management 70(1995): 61~68.
3. Tang ShouZheng, Li Yong.1996.An Algorithm for Estimating Multivariate Non-liner error-in-measure Models. Journal of Biomathematics. 11(1): 23~27.
4.Tang SZ, Li Y,Wang YH, 2001, Simultaneous equations, error-in-variable models, and model integration in systems ecology Source:ECOLOGICAL MODELLING, 142 (3): 285-294
5.Tang SZ, YH Wang, 2002, A parameter estimation program for the error-in-variable model, 156(23):225-236
6. Li YongCi, 2004,Study on Parameter Estimate of Growth and Harvest Models Based on the Methods of Mixed Model and Measurement Error Model. Doctor Thesis (Chinese with English abstract ).
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