Physiological Ecology of Forest Production

341 Pages·2011·4.871 MB·2-325\341

Volume4 in theAcademic Press | TERRESTRIAL ECOLOGYSERIES
Editor-in-Chief
JamesR.Ehleringer,UniversityofUtah,USA
Editorial Board
JamesMacMahon,UtahStateUniversity,USA
MonicaG.Turner,UniversityofWisconsin,USA
Books in the Series
ToddE.DawsonandRolfT.W.Siegwolf:StableIsotopesasIndicatorsofEcological
Change,2007
Keith A. Hobson and Leonard I. Wassenaar: Tracking Animal Migration with
StableIsotopes,2008
RobertA.Garrott,P.J.WhiteandFredWatson:LargeMammalEcologyinCentral
Yellowstone:ASynthesisof16YearsofIntegratedFieldStudies,2008
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Acknowledgements
I
n the course of preparing this book, a number of people read and commented on the drafts of
various chapters; some did so in detail, providing us with invaluable comments, queries and
suggestions. Most of these people are busy professional scientists and university teachers, and
theirtimeisvaluable.Wethereforegreatlyappreciatethegiftofsomeofit.Inparticular,wethankRam
Oren (Duke University, NC), Belinda Medlyn (Macquarie University, NSW), Philip Smethurst
(CSIRO, Hobart, Tasmania), Torgny Na¨shlom (Swedish University of Agricultural Sciences, Umea¨,
Sweden), Auro Almeida (CSIRO, Hobart, Tasmania) and Richard Waring (Oregon State University
Corvallis,OR)whoallreadandprovideddetailedcommentonthedraftofvariouschapters.Aswellas
reading and providing comment on chapter drafts, Dick Waring also drew our attention to relevant
papers and provided copies of many that we had difficulty in obtaining. Auro Almeida provided
comment on drafts and made available data from his work in Brazil, as well as copies of papers we
couldnotaccessovertheworldwideWeb.HespentsignificantamountsoftimewithPJSdiscussinghis
workanditsimplications.LukeEspreyprovidedcommentonachapterandsomeinsightsintoforestry
in South Africa. MikeRyanchecked our statements about some aspects of respiration toensurethat
they were consistent with conventional wisdom. Chris Beadle, Dale Worledge and Tony O’Grady
(CSIRO, Tasmania) also made available various climatic and soil temperature data, and Vanessa
Haverd(CSIRO,Canberra)thedataforonesetofcanopyprofilesshowninFigure2.11.Weacknowl-
edge permissionfrom Cambridge University PresstoreproduceFigure9.3fromJones(1992)‘Plants
and Microclimate’ as our Figure 2.8, and from Oxford University Press to use Figures 3 and 4 from
Cˇerma´ketal.(2007)(TreePhysiology27,pp.181–198)asourFigure7.7.Wewouldalsoliketothank
ElsevierandTreePhysiologyformakingavailabletousfreesubscriptionstotheirelectronicresources,
supplementedbytheservicesofMessrsGoogleandWiki.
vi
Preface
T
his book was originally planned as a second edition of ‘Physiological Ecology of Forest
Production’, whichwas published by Academic Press in 1986. Encouraged by friends among
the community of tree ecologists, physiologists, and foresters who were generous in their
appreciation of the original, I approached Academic Press and we negotiated a contract. Academic
Press was, a little later, bought out by Elsevier, but they honoured the contract, and the editors
at Elsevier have been patient with our inability to meet the submission date that was originally
agreedupon.
Myinitialoutlineowedmuchtotheearlierbook,butIwaspainfullyawareofhowmuchprogress
had been made in our field in the quarter century that had passed since that was written. This was
clearlynotgoingtobearevision,butratheranalmostcompletelynewbook.Itwasalsocleartomethat
I needed help: I needed a coauthor who was familiar with the field of physiological ecology and
modelling,withparticularreferencetotreesandforests,whohadtheskillsnecessarytomakeupformy
shortcomings,andwhowasinterestedandhadthetimetogivetothebusinessofwritingatechnical
book.Fortunately,PeterSands,whohadrecently retiredfromtheCSIRO(CommonwealthScientific
and Industrial Research Organisation, Australia), met all those criteria. We had done some work
togetherandkneweachotherwell,andherespondedpositivelyandenthusiasticallytomyinvitationto
joinmeinthetask.
Peter had worked with various types of models relating to forestry for many years and had been
involved with a number of projects where he provided the mathematical skills needed by biologists,
ecologists,andforesters.Hehadrewrittenthesoftwareforthe3-PGmodelthatIhadproducedwith
my great friend and colleague Dick Waring from Oregon State University, and that flexible and
powerful software has been a key factor in the success of that model, which is mentioned frequently
and discussed in detail in this book. The fact that Peter lives in Tasmania and I live in the Blue
Mountains in New South Wales was no obstacle to our collaboration: we had broadband internet
connections and that is all you need nowadays. In extremis we could resort to the telephone, but
seldomneededto.IthasbeenarealpleasureandastimulatingexperiencetoworkwithPeter;thebook
wehaveproducedistheresultofacompletelyequalpartnershipandequal,mutual,effort.Therehave
beenfewsignificantdisagreementsandthosewereresolvedwithoutstressorproblems.
In the preface to the 1987 book, I said that my objective was to demonstrate how a quantitative
approach to whole-plant physiology, coupled with some knowledge of the physics of plant environ-
ments, allowsus to analyze the way trees grow, and the wayenvironmental factors and management
actionsaffectgrowth.Thatobjectivehasbeenextended,inthisbook,toincludeconsiderationofthe
modelsthathavebeendevelopedtodescribemanyoftheprocessesthatunderlieandgoverntheway
treesgrow.Itisthesemodelsthatprovidethetoolswithwhichknowledgeandunderstandingcanbe
translatedintothequantitativepredictionsneededbymanagersanddecision-makersconcernedwith
forestproductivity,hydrology,andwaterbalanceorcarbonsequestration.
Our target audience is teachers and graduate students in forestry, ecology, and ecophysiology.
Althoughour(limited)knowledgeofundergraduatecoursesaroundtheworldintheseandassociated
fieldssuggeststhatthetextisprobablynotpitchedatalevelwhereitwillbeusefultoundergraduates,
there is no reason why some undergraduate courses should not be able to make use of it. We also
hope that the book will be useful to established scientists who may find that the coverage of areas
outsidetheir specialtiesisofvalue,andtoforestmanagers whowanttounderstandtheir forestsata
deeper level. The book is wide-ranging and, for biologists and foresters unaccustomed to think in
vii
viii Preface
mathematicalterms,thetreatmentofvariousprocessesmaysometimesseemdense.However,wehope
you will persevere. The properties and behaviour of many of the equations can be explored in the
spreadsheetsandothermaterialonthePHYSECOLWebsiteElsevierestablishedspecificallytoaccompany
thisbook,andwherethecodeforthe3-PGmodelcanalsobefoundanddownloadedwithoutcharge.
We have had in mind, throughout the writing of this book, the idea that the various (first order)
processes that contribute to, and determine, the way trees respond to their environment, and grow,
should be considered in relation to the process of growth (biomass accumulation) as a whole.
Theindividualbiophysicalprocessesareusuallystudied,asfaraspossible,inisolation,butthegrowth
ofatreeisacomplexprocessofinteractionsandfeedbacks,soweneedtoconsiderthesystemaswhole.
The framework withinwhichwecan do that isa process-basedmodelthat constitutes an attemptto
describe growth in quantitative, mathematical terms. So, all the chapters dealing with individual
processes are set within such a framework, and in the second last chapter, we deal in detail with
the3-PGmodel.
Asalways,withexercisessuchasthis,anumberofpeoplehavecontributedtheirtimeandexpertise
to help us avoid factual mistakes and to offer suggestions about matters where our treatment was
inadequate. In most cases, these people are busy professional scientists for whom it is not a trivial
mattertocommitvaluabletimetoreadingandcommentingondraftchaptersofsomeone’snewbook.
Weareverygratefultothosewhodidthis;theyhelpedconsiderablytoimprovetheproductbutbearno
responsibility for our mistakes and shortcomings. These friends and colleagues are named in the
Acknowledgements, but here I want to thank, particularly, Dick Waring, who not only offered
comment, advice, and encouragement, but also did his best to make sure that I kept abreast of the
literature. He drew my attention to numerous papers I might otherwise have missed and frequently
obtainedandsenttome pdfcopiesofpapersthat Icouldnototherwisegetaccessto. SinceIdo not
haveaccesstoalibrary,thiswasassistanceofimmensevalue.
It is customary, at this point in the preparation of a book, for the author to thank his family for
toleratinglongperiodsduringwhichhewasantisocial,notavailableforfamilyactivities,andgenerally
focussedonaprojectinwhichtheyhadnopart.However,thingsareabitdifferentinmycase.Being
retired,thewritingprojecthasprovidedmewithanactivitythatkeptmybrainactiveandkeptmein
touchwithmyfriendsinthescientificcommunity,whichhasbeenanimportantpartofmylifefor40
years. Mychildren have long since left home and my wife, Diana, is generallyquite happy to see me
peckingawayonthecomputer(shehasherown,sothereisnoconflictonthatfront),providedIdonot
useitasanexcusetoescapedomesticandgardeningduties.Sheisalwayssupportiveand,althoughshe
contributedlittletothisbook,withoutheritwouldnothavebeenwritten.
Joe Landsberg
‘Withycombe’, Mt Wilson NSW
April 2010
I fully endorse Joe’s comments about our work on this book! It has indeed been a pleasure and
inspirational.Aboveall,itwasarealjoytohavetheopportunitytoimmersemyselfinscience,simply
for its own sake, free of the need to justify what I was doing to some organisation, and free of
organisational politics. Thanks, Joe, for this opportunity! It has also been a pleasure to be on this
journey with Joe and to build on our working relationship through the sharing of anecdotes in our
lives,thedoingsofourfamilies,andthevariedclimatesofourphysicalenvironments.Therehasbeen
farmoretowritingthisbookthanthescienceyouaregoingtofindherein!
I came to plant physiology via a ‘sea change’ into mathematical modelling of natural systems in
severaldivisionsoftheCSIRO.Thiswasafter10yearsasatheoreticalphysicistdevelopingandapplying
techniquestoanalyze—anddesign—opticalimageformingsystemsandtomodeltheeyesofvarious
animals.Intheprocess,IbecameabitofaJackofAllTrades—butMasterofNone—invariousareas.
My first project in that new phase of my career was a collaboration with Dick Hughes developing a
Preface ix
model of the population dynamics of that pesky little irritant of the Australian bush: the bush fly
(HughesandSands1979).Thiswasmyintroductiontothenatureofbiologicaldataandhowradically
it differs from the data captured by physicists and engineers. It was also my first taste of working
alongsideabiologist,andIamgratefultoDickformakingthat,too,sucharewardingandpleasurable
experience.Atthesametime,myteamleaderinCSIROwasPeterBenyon,amodellerwhohailedfrom
weaponsresearch,whotaughtmetheimportanceoflookingatthewholesystem—notjustthebitsthat
werethecurrentflavourofthemonth.Peterisnolongerwithus,buthisrespectforotherdisciplines
andrigourremainapartofmywayofthinking.
Duringthewritingofthisbook,Isuffereddetachedretinasinbothofmyeyes,oneofwhichisstill
byno meanssatisfactory. This unfortunate excursioninto the practical aspectsof myearly academic
interestsledtotheneedforasignificantextensionofthecontractfordeliveringthisbook.Forthiswe
aregratefultooureditorsatElsevierfortheirunderstandingandflexibility.
Finally,Iwouldliketoexpressmythankstomyfamily,especiallytomywifeKrista,forhersupport
andpatiencewithmy,attimes,annoyinglyone-pointedapproachtolife,andtomygrandchildrenwho
havehad a ratherelusiveOldGrumpforawhile. However, Istill hadtotakemyshareof household
responsibilities!
Peter Sands
39OakleighAv.
Taroona, Australia 7053
For thePHYSECOLWeb site, go tohttp://www.elsevierdirect.com/9780123744609
Table of Symbols
W
edefineherethesymbolswiththeirunits,andcommonsubscripts,asusedinthisbook.All
symbols are defined in the text where they are first used, with their units given, and are
sometimes redefined—as a reminder—later. We have not necessarily included in this list
symbolsthatoccuronlyonceinthebook.Wehavealsolistedgenericsymbols,thatis,withsubscripts
omitted,andinseparatelistsbiophysicalconstantswiththeirstandardvalues,andsubscriptsandtheir
meaning.
The units given are usually the base units, whereas when values are given prefixes are used. For
example, the base unit of assimilation rate is molm(cid:1)2s(cid:1)1 but values are typically given in
mmolm(cid:1)2s(cid:1)1, and the base unit of water potential is Pa but values are usually given in MPa. Some
quantitieshavedifferentunitsdependingontheircontext.Acommonexampleisconductance:ifitisa
molarfluxitsunitsaremolm(cid:1)2s(cid:1)1,whereasifitisamassfluxitsunitsare(usually)ms(cid:1)1.
Whilewritingthebookwetriedtobeconsistentwithconventionaluseintheliteratureconcerned
withenvironmentalphysicsandplantecophysiology,insofarasthereisanyconsensusamongusersin
thismatter.However,becauseoftherangeofmaterialcovered,ithasbeendifficulttoavoidusingthe
samesymbolorsubscripttodenotedifferentvariablesonnumerousoccasions.Forexample,Hdenotes
heat flux in Chapter 2, but is also used to denote stand or canopy height, and a parameter in the
temperature response of the photosynthesis model. We have decided to accept this problem because
manysymbolsarewidelyusedinparticularcontextsandchangingthemmayleadtogreaterconfusion
thandoesduplication!
Wealsorelyonacertaindegreeofcommonsenseanduseofcontextwheninterpretingasymbol.For
instance,Astandsforanareaandforanassimilationrate,andsubscriptsBimpliesboleorbasalandC
canopy.ThusAisleafassimilationrate,A isbasalarea,A iscanopyassimilationrate.
B C
(a)Biophysicalconstants.Thefollowingarethevaluesofvariousbiophysicalconstantsusedinthetext
Symbol Meaning Units Value
c Specificheatofdryair Jkg(cid:1)1K(cid:1)1 1004
pa
D Diffusivityofwatervapourinair m2s-1 2.4(cid:3)10-5
v
g AccelerationduetogravityatEarth’ssurface ms(cid:1)2 9.81
I Solarconstant:averagetotalirradiancenormaltobeam Wm-2s(cid:1)1 1367
SC
externaltotheatmosphere
M Assumedeffectivemolecular weightofplantdrymatter gmol(cid:1)1 24
DM
P Pressureofstandardatmosphereatsealevel kPa 101.3
0
q MJofphotosyntheticallyactiveradiationpermoleof MJmol(cid:1)1 4.6
MJ
photons
R Universalgasconstant Jmol(cid:1)1K(cid:1)1 8.3145
e Ratioofmolecularweightsofwaterandair – 0.622
g Psychrometricconstant PaK(cid:1)1 66.1
l Latentheatofvaporisationofwater MJkg(cid:1)1 2.45
xi
xii TableofSymbols
s Stefan–Boltzmanconstant Wm(cid:1)2K(cid:1)4 5.67(cid:3)10(cid:1)8
r Densityofdryair kgm(cid:1)3 1.204
a
r Densityofwater kgm(cid:1)3 1000
w
(b)Genericsymbols
[Q] ConcentrationoftheentityQ molm(cid:1)3,
kgkg(cid:1)1
a Ascalefactor,forexampleinallometricrelationships;intercept Various
inlinearrelationship
A,A ,A Assimilationrate,RubiscolimitedA,RuBPregeneration molm-2s-1
C j
limitedA
A ,A Standortreebasalarea,maximumstandbasalarea m2ha(cid:1)1,
B Bx
m2tree(cid:1)1
a Foliageareadensityincanopy m2m(cid:1)3
F
A Areaofentity i m2,ha
i
b Slopeinlinearrelationships Various
b Parametersinexpressionforg (i¼1,2,3) Various
i cS
B Fractionofwaterintissuethatisbound –
t
C Capacitanceoftissueforwater m3Pa(cid:1)1,
kgPa(cid:1)1
C Genericsymbolforconcentration kgkg(cid:1)1,
molkg(cid:1)1
C ,C,C CO concentrationorpartialpressure—atmospheric,atleaf molmol(cid:1)1,Pa
a s i 2
surface,intercellular
C(cid:4) IntracellularCO partialpressureatwhichtheRuBP-saturated molmol(cid:1)1
i 2
andRuBP-limitedratesofphotosynthesisareequal
c Genericsymbolforspecificheat Jkg(cid:1)1K(cid:1)1
p
C Electricalconductivityofsoil dSm(cid:1)1
S
d Apparentreferenceheight m
d Characteristicdimensionofleaf cm
d Depthofdrysoillayer mm
D,D Vapourpressuredeficit,valueofDcharacterisingarelationship kPa
0
withD
d,d Genericsymbolforadiameter,diameteratbreastheight cm
B
D,D,D Diffusivity,ofwaterinsoil,andinsaturatedsoil m2s(cid:1)1
s sat
d,d ,d Numberoffrostsinmonth,totaldaysinmonth,rainydaysin daymonth(cid:1)1
F m R
month
D ,D Decompositionrateoflitter,andofstructurallitter kgm-2yr-1
L s
d Dayofyear(1January¼1) –
n
E Activationenergy—parameterinK(T) Jmol(cid:1)1
E Elasticmodulusofstem Pa
E Transpirationrateperunitleafarea molm(cid:1)2s(cid:1)1
e Vapourpressure kPa
E,E Rateofevaporation,rateofevaporationfromwetsurface kgm(cid:1)2s(cid:1)1
0
e ParameterineffectofwaterstressonL –
C0 cc
e Annualaveragecropfactor –
Cav
E ,E Equilibriumandimposedevaporationrates kgm(cid:1)2s(cid:1)1
eq imp
E ,E Rateoftranspirationperunitleafarea,andperunit kgm(cid:1)2s(cid:1)1,
L T
groundarea mms(cid:1)1
TableofSymbols xiii
E Totalevaporationfromsoil kgm(cid:1)2,mm
S
e,e Actualrateofevaporationfromsoilsurface,potentialrateof mmh(cid:1)1
s s1
soilevaporation
E ,E Totalevaporationfromsoilduringphase1,phase2evaporation mm
s1 s2
toreducesoilevaporationrateto50%
F Fluxofanentity Various
f,F Afraction,forexamplediffuseradiationasfractionoftotal –
F Weightingfunctioninmixed-specieslightinterceptionmodel –
H
f Amodifierwhereiissymbolofvariable,forexamplef iseffect –
i T
oftemperatureongrowthorconductance
F Indexofsitefertilityasusedin3-PG –
R
FS IndexofsitefertilityornutrientavailabilityasusedinPROMOD –
G Fluxofheatintostorageinground Wm(cid:1)2
ms(cid:1)1
g Genericsymbolforconductance
molm(cid:1)2s(cid:1)1
g ,g ,g , Conductances:boundarylayer,ofcanopy,ofcanopyata ms(cid:1)1
b C Cref
g ,g ,g referenceVPDof1kPa,forheat,ofstomata,forvapour
H S V
g ,g ,g Conductances:boundarylayerofsoil,ofsoilsurfacelayer, ms(cid:1)1
bs Cs Csx
maximumvalueofg
Cs
g ,g ,g , Actualandunconstrained(optimal)canopyconductancein ms(cid:1)1
C Copt Cn
g 3-PG,g foropencanopy,species-specificmaximumg
Cx Copt C
H Enthalpyofactivestate—parameterinK(T) Jmol(cid:1)1
H Treeormainstemheight m
h,h Measureofdaylength h,sday(cid:1)1
d
H Relativehumidity –
r
I Genericsymbolforirradiance Wm(cid:1)2
I ,I Irradianceinhorizontalplaneabovecanopyandabove Wm(cid:1)2
0 S0
atmosphere
I ,I ,I Irradianceindirectbeam,diffuseirradiance,totalirradiance Wm(cid:1)2
dir dif t
I Irradianceonleaf Wm(cid:1)2
l
I Amountofrainfallinterceptedbycanopy kgm(cid:1)2,mm
R
i ,i Fractionofrainfallinterceptedbycanopy,itsmaximum –
R Rx
J Genericsymbolforflowrateorflux Various
J,J ,J Genericsymbolforflux,diffusivefluxrate,massfluxrateof molm(cid:1)2s(cid:1)1
D M
nutrients
J,J Rateofelectrontransportanditsmaximum molm(cid:1)2s(cid:1)1
max
J ,J,J,J Volumeormassflowrateoutofstoragetoxylem,outoffoliage m3s(cid:1)1,kgs(cid:1)1
c f s x
(transpiration),fromsoiltoxylem,fromxylemtofoliage
J Volumeormassfluxofwaterinsoil m3m(cid:1)2s(cid:1)1,
s
kgm(cid:1)2s(cid:1)1
K Diffusioncoefficientinair cm2s(cid:1)1
K Genericsymbolforarate Various
k Genericsymbolusedinvariouscontexts,ofteninrate Various
relationships
K Genericsymbolforhydraulicconductivity ms(cid:1)1
K,K ,K Michaelis–Mentenparameter,Kforcarboxylation, Pa
C O
Kforoxygenation
xiv TableofSymbols
k,k ,k ,k Lightextinctioncoefficient,effectiveextinctioncoefficient, –
eff H R
extinctioncoefficientforhomogeneouscanopy,rainfall
extinctioncoefficient
K ,K Michaelis–MentenparametersforCandNinnutrientuptake kgkg(cid:1)1
C N
rate
K Turbulentexchangecoefficientforentity i(i¼m,V,H) m2s(cid:1)1
i
K,K Hydraulicconductivityofsoilandofsaturatedsoil ms(cid:1)1
s sat
L Genericsymbolforalength m
L Latentheatflux Wm(cid:1)2
L Leafareaindex m2m(cid:1)2
L Ligninconcentration kg1kg(cid:1)1
L Annuallitterfallrate kgm(cid:1)2yr(cid:1)1
a
l Leafareaperunitgroundareainlayeri m2m(cid:1)2
i
L ,L,L Nutrient,temperatureandsoilwaterdeterminedLAIindexofa m2m(cid:1)2
N T W
closedcanopy
L ,L ,L Rootlength,L perunitgroundareaandperunitsoilvolume m,mm(cid:1)2,
R RA RV R
mm(cid:1)3
L ,L CanopyLAIabovewhichfractionofinterceptedrainfalldoes m2m(cid:1)2
Rx gCx
notincrease,andabovewhichcanopyconductancedoesnot
increase
m Leaftransmittance –
M Rateofmetabolicenergyexpenditure Wm(cid:1)2
m Slopeoflinearrelationship Various
m,m ,m Opticalairmassofatmosphere,standardairmassandrelative –
0 r
airmass
m Fractionofbiomassinpooliofanaveragetreeassociatedwitha –
i
dyingtree
n Fractionofradiationincidentonleafthatistransmitted –
N Genericnitrogenconcentration kgkg(cid:1)1
n Genericsymbolforapower,forexampleinallometric –
relationships
N,N Nitrogenmineralisationrate,mineralizationrateofwetsoil kgday(cid:1)1
base
N FoliarNcontent kg
F
N Numberoftreesinastand Trees
S
N Populationdensity Treesha(cid:1)1
S
O Partialpressureofoxygen Pa
P Atmosphericpressure Pa
p Porosityofsoil –
P,P ,P Genericsymbolforproduction,grossP,netP kgtree(cid:1)1,
g n
tha(cid:1)1
P ,P AmountofCandNinactiveSOMpools kg
aC aN
p FractionofstembiomasspoolW asbranchesandbark –
BB S
p ,p Foliage:shootandroot:shootallocationratios(i.e.(cid:1) /(cid:1) ,(cid:1) /(cid:1) ) –
FS RS F S R S
Q Agenericquantity Various
q Genericsymbolforaflowrate Various
q Specifichumidityofair –
Q,Q GenericsymbolforinsolationoraccumulatedPAR,insolation Jm(cid:1)2day-1
0
abovecanopy