Comparison of Modelling Approaches for Managed Red AJder Stands Steven A. Kaowe
Oregon State llnivelmy Oeportment afForest 5<ience Glenn ft Altrens
Oregon State Universiiy Oeportment af .Corest Sdenm Dean S. OeSeU
USDA Forest Sertica Forestry Sdences l.aaaratury Introduction
Red llder
(Alnus l'.tiJra B ong) is
l.
o{cedalderpiant::t.tioas. T'ne
a.
st:Lnd-tcvei in±ormarion; a stand c;�_bie :Jroiec-:5on me
widely distributed
!fu.t u5es boch st:llld- md cree-lC"rel informacion; md m
individu:U-cree growth modeL
C:enred as a cesult or harvesting in the Dougias-!ir ::egion. cimber reroun:e h.as inc::'e:Ised in
Diameter distributions ob(aincod for c.ac.h modeling j<
•
'
'
••
'
o.ons ror r:mge or p�.ana.ng u.en!imfs, ,-,_ reo :•tQJ: spac"!g
•
,.
....
I
•
!
•
'
\
J
I
smdy was est::t.blished Ln 1974 ne:u A!)i�H)') Oregon. lr.d
\nc::nci.ve co rn::tnage red :Ude::. Much of :he growth md
included six planting densities: 976 (3.2 x 3.2 m), 1600
(2..5 X 2..5 m), 3086 (1.3 X 1.3 m), · 6.30 (1.2 X 1.3 :n),
yield rese:treh in red. :Uder has be:1 conduc:ed in aarur:zl
s;::::.nds and has foc.ISed on size-densic-r relationships,
6944 (1.2 x 1.2 m), md 13 889 (0.6 x 12 en) crees/ha.
Each p.l:mring densic-rwas represented by one or twO fllots.
ci:te ne-:d.
ver:r !ittie is known about growth md dC"rdopment of
Dirunc:e: orthe surviving tre:'..s on e:1e-.l; plot was m.e:t.sqred
man:1.ged red alder stands. Deniled quanci.cacive
info rmacion cegarding che silvicultur:tl md economic
consequences of ciifferenr
.I-
'
>t:mds wi.th. Douglas - fir (Prauiotsugrz mcr:ziei£) m:ty be m
curves. Despite
.
--l.. d we:e comparea co me." oosc""'"'' <'l .ffifi:G' Clis-=:oucn�:wo
:ec::nt yeru:s. The ?Ot:encial for nitrogen fi.urion Ln mi:ced
ch.i.nning eifects, md height
od
'
'
n::t.rciwood species in me P:u:ific Northwest that has ?COll­
Incerest in ced :Uder as a.
:nodding :�ppronches inc!ucie
diameter d.isrriburion prediction md1od tr J.t uses onLy
liUluallr be::ween
?hncrioo.
'> /" md 12, 14, md .16
ye-:us. T.ce: md sc.nd d:u:a we;r; :nT;lngui in. non-ove::
phnring densities is needed.
­
l:J.opitUJ'
_zrowth series of 1 or 2 YG•f$.
... .. ---:::1 .....
T:-:.e purpose of chis smdy was co de-relop md compare
. d-...ree :�.pproaches co madding che scruc:ure md dyn:un.ics
21
I
·
.
Ecology and Management of B.C. Hardwoods
Survival Function
Individual-tree Diameter Growth
.-\. :>urviva..l func:ion (Clurrer and Janes 1980) was sdec::ed Tne diameter growdt func'cioa fur individu:ll crees is sim..ii:Ir co che functions de•:eloped by Hann :md Larsen (1991). A ere: list is required co make growth predictions tor ti"Ced growth. intervals. The function is applic::tble co .:-�en- or uneven-uged scmds cimc have been chinned or St:lilds with multiole Clllooies. The oocenrial annual diameter growth of individual 'trees is ? edicced as a function of cunene diam er. Smailer cre::s have a gre:trer potenri:ll for growth .
chan larger crees. The eocenrial growth is mod.iiied by basal a.re:t oflarger dbh trees (BAL) and stand basalate:t. Thus, smaller cn:es in :t srand have less growr:h. rb.a.n che larger
crees. and t:rees in scmds with low basal are:�. ahibir gre:tter growth clu.n crees in c:tnds wich higher basal are:t. Sc::md morcilicv is allocated co dbh classes assuming due smaller crees in smnd h.ave l. greater probability of dying c:h:ul che larger crees. :"or use [a ill c.b.ree modeling approaches. This function is based on Lhe assump tion char sc.nd mort:tlicy is prop o r ­
cional mage and density; and is age- and path-invarian:c. Diameter Dis1ribution Prediction Approach Tnis aooroac.:,. is most useful for comoaring che e!fecrs of d ensity when l. cree
is at awilable. Only st:md-!evd inrormacion is aeeded co gene.":lte a diamete: distrioucion :u my age. Com pon en ts of chis approa6 include Lhe ;urvival Eunc-:ioa, a basal area predic:ion function cb.ar .i.s asvmotocic ·nitb. resoec:-::o domirutnr heignr an d densirv. oredtc'ci n functions for Lhe Oth, 25ch, 50ili,
·' .
1nd 95 ch ciiame ::r distribution oe:r:::.'lriles, and a oaramer:r :ecove:-r oroc:::dure for the cb.rc -oar:unerer Weibuil distri­
bution fu'ac:ion (Knowe :tal. 1992). Tae quadratic rnem diam erer i."l c. e oreciic-::ed disr:ri.Outions is the same as impli­
d by 2reciic:io equations for scmd basal ::tre:1 and survival. eianci g
Stand Table Pro{edion Appr.oach
a fu ru r e stlnd cable chat is
wich s tand- and cree-[eve.!. functions (Pienaar
md Harrison 1988). A o:ee list and stand .informacion are
:1 e e ded . Comoonencs of cb.e stand cable projection
This aooroac.i oroduces
'
consis;:
t
:J.ooroach incl de che survival funccion, a basal area
? jec-::ion :Unc::ion cb.ac is functionaily compatible with
ciJ.e basal are:1 :Jted.icrioa function and is boch age- and
oach-mvarianc.' :md a diameter orojecrioa func:ion for
indi vid ual cre:s based on re!arive 'cree size, defined as che
::1.cio ofindividual-cree basal a.re:t co aver:z.ge basal m:;x. per
cro:: tn me smnd. .Any growth incerval m·ay be used. Tae
future d.iamer::: of individual cn:es c:m be estimated from
me produc-e oi projected relative ::ree size and projec:ed
:nem size oboined from cb.e srand-(e-td survival and basal
:tre:l. fu.nc-:ions. The relative size projec-:ion function for
individual crees c:m be constr:lined co
consistenc:r
of me future smnd m.ble with stand-!C"td basal are!!. and
surviva..l. func::ions. Scand morcility is illooted co dbh
classes ass!lming mat smaller crees in a smnd have a gn:::r.cer
p rob a bility oi dying r:han larger crees.
Resuifs
Tne cwo-s:unpie Koimogorov-Smimoi! cest was used co .
de!:e:mine whether :he observed :md pn:dicced or projet:ed. diameo:er discribucions :tre samples from c.he same
oooulacioa. For u.'le d.iamerer distribution ?reciiccion o;roa.ch, che oreciicred and obser-red diame!:er
als butioas we significantLy ditterent tor cwo ?LOts
(2.9% of coml) cor:::spoad.ing ::o 1399 crees/h:t ?lancing
density (ages 14 mci 16). For cb.e send cable projecion
a ?p roa ch, che ooserved and projec-.:ed diame::e:
d.isrricutions we.""::: signi.fic:mciy different for cwo plots
(2.9% oi che coati) corresponding to 13 399 crees/h::t.
f'i:lnci.ng' density (age 16 only). For che individual-ere::
growth. approach., che observed and projec::ed. dia.me
:er
dist:riburions were significantly different for one ploc ( l..J%
of chc: cor:al) corresEJond.ing co 1600 creeslha. pl:mri.ng
density (age 16 only). Visual inspections of di:une::er
disrricurions reve:tled che diameter distribution prediction
aooroach cends co ove=·ored.icc dbh for !.arger o:ees in st::l..11ds
pl red at high densi ty. The st:1nd c:a.ble projeccioa
approach. tends to under--predict dbh for sm:t!ler trees in
St:lilds pla.nred at low density and to over-predict dbh for
smaller· c:rees in stands plance d ac high density. Tae
individual-ere::: growth ap p roac h provides che best
cepresent:ation of observed diameter distributions at ill
planting densities.
212
Ecology and Management of B.C. Hardwoods
Literature Gted
Condusions The diameter districucion prediction approach gives a
reasonable represencacion of che smooched diameter
distribution, and may be llSe...ui. for comparing ?lancing
densities when a crc:e list: is not: available:. The: st::l.lld c:tbie
oroiecrion aooroa6 orovides for consistcncv between
I,
..
lo
..
'
smnd- and. crc:e-!evd growth projections, and should. be
•.1se.fu..l tor compa.riag planring densities when a cn:e list: :s
available. The individu.al-cree growth approach may be best:
suiced :or smnds chat have been ::hinned. st:utds with
mi."mU'es o£ species, or st:Ulds with various size classes.
Clutter, J.L. and E.P. Jones. 1980. P:-edicrion of growth
mer chinning oid-:ie.!d slash oine olanocions.
USDA For. Se..··v. R<!S. Plp. SE-21J. H p.
Hann.
D. . an
D .R. Lusen. 1991. Di.ame r growth
.
quanons tor fourteen cree soecies in southwest
Bull. 69, Coll For..,
Corvillis, Oreg. 13 f'·
Oregon. For.. Res. W.o. Res.
Oreg. Scate Univ
.•
Knowe, S_'\.., T.B. H
amn. and R.G. Shuh. 1992.
Incorponcing chc: :.=:c:s ofincc:"S?c:cific
competition md •rege':ltion mana.gemc:nc
crc::mnents
in d.iamc:::r distribution models for
Doug.L:ts-&r sapiio..g;. Cm. f. For. Res.
22: 1255-1262.
P!c:naa.r, L. V. and W.)IL Har::-ison. 1988..'-\.sand cable:
proje c:ion ap?roac.. :o y-ield ?reciic::ion in
unthinned l!"ten-.tged
34: 304-308.
213
sends. For. SC:.
Ecology and Management of B.C. Hardwoods Workshop Proceedings December 1 and 2, 1993, R.t.'chmond, B. C. Edited by Philip G. Comeau', George J. Harper:, Man1yn E. Blacnet, Jacob 0.. Bo ateng2, and Keith D. Thomas1 t
B.C. Min.imy oiForesa, Resc::l1'cit Br:mc, V1c:orU. S.C. Z B.C. Ministry oiForc:m, Siivic'.l1ture Pr:�.ccic:s 3r:m6. Vicrori:t. B.C. October 1996 FRDA Report Mo. 255 ; CANADA-BRITISH COLUMBIA PA.RI'N'ffi.SHlP AGREEvfEJ.'IT CN FOREST RESOURCE DEVELOPMEN1
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!Canada l
FRDA II