nutrients and water relations in mediterranean

7/27/2019 Nutrients and Water Relations in Mediterranean

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Nutrients and Water Relations inMediterranean-Type Ecosystems1

Philip C. Miller2

Gen. Tech. Rep. PSW-58. Berkeley, CA: Pacific Southwest Forest and Range

Experiment Station, Forest Service, U.S. Department of Agriculture; 1982. 325

1Pr esented at t he Symposi um on Dynami cs and

Management of Medi t er r anean- t ype Ecosyst ems,

J une 22 26. 1981 San Di ego, Cal i f or ni a

2Di r ect or , Syst ems Ecol ogy Resear ch Gr oup, San

Di ego Stat e Uni ver si t y, San Di ego, Cal i f orni a 92109

Abstr act : Medi t err anean regi ons of t he worl d ar e

char acter i zed by wi nter r ai n, summer drought

pr eci pi t at i on cycl es and by thei r gener al l y l ow

nutr i ent st atus. Thi s paper r evi ews concept s

r el ati ng to water and nut r i ent use by vegetat i on

i n t hese r egi ons.

The br oad cor r espondence bet ween t he

scl er ophyl l ous shrub f or m and the cl i mat e i n

medi t err anean- t ype ecosyst ems i ndi cat es a

cl i mat i c cont r ol over t he veget at i on par t i cul ar l y

wi t h respect t o t he summer dr ought , but al l f i ve

r egi ons ar e noted f or nut r i ent def i ci enci es,

especi al l y Aust r al i a and Sout h Af r i ca. As

st udi es of t hese ecosyst ems ar e compl eted,di ver gences r el ated to t he cont r ol of communi t y

st r uct ur e, f unct i on, and f orm are becomi ng

appar ent . Di f f erences i n speci es composi t i on and

growt h f orm are appar ent on nut r i ent poor and

base ri ch si t es (Specht and Mol l 1981). The

medi t er r anean type ecosyst ems i n Sout h Af r i ca and

Aust r al i a are general l y consi dered nutr i ent poor

r el ati ve t o t he medi t err anean- t ype ecosyst ems i n

Chi l e, t he Uni t ed St ates, and the Medi t err anean

Ar ea. I n Aust r al i a phosphorus l i mi t at i on i s

assumed t o have sel ected f or scl erophyl l y, whi ch

preadapted the f l ora t o t he more r ecent summer

drought cl i mat e (Beadl e 1954, Specht 1979 Mol l

and ot hers 1981) . I n Sout h Aust r al i a the

overst ory vegetat i on i s bel i eved t o be ever gr een

because of cl i mate, whi l e the underst ory i s

ever green because of nut r i ent i mpoveri shment

( Specht 1972) . I n Cal i f or ni a t he over st or y i s

bel i eved t o be evergr een because of cl i mate, and

t he under st ory i s deci duous because of

mi crocl i mat e near t he soi l sur f ace ( Mi l l er 1981) .

Nutr i ent def i ci enci es have been suggest ed t o

expl ai n ot her aspects of t he communi t y st r uctur e

i n t he medi t er r anean- t ype ecosyst ems; such as

successi on f ol l owi ng f i r e ( Specht 1972) , speci es

r i chness i n Sout h Af r i ca ai d Aust r al i a ( Kr uger

1979) , t he di st r i but i on of f ynbos and heat hl ands

i n Sout h Af r i ca ai d Aust r al i a over a wi de range

of annual preci pi t ati on ( 300- 3000 mm/ yr) ( Specht

1979) , and speci al i zed morphol ogi cal st r uct ur es

( Lamont 1972, 1973, 1980, 1981) .

I n cont rast , i n Cal i f orni a and Chi l e the

l engt h of t he summer dr ought i s t hought t o

cont r ol scl erophyl l y ( Mi l l er 1981) . Evergreen

scl erophyl l ous shr ubs are bel i eved t o occur i n

Cal i f orni a wher e t he l engt h of t he soi l dr ought

i s about 100 days or l ess ( Mi l l er and Mooney

1974) . I n Cal i f orni a t he l eaf area i ndex devel ops

unt i l water use by t he chapar r al cr eat es adrought l asti ng about 100 days ( Mi l l er and Pool e

1981) . I n Aust r al i a ever green shrubs moderat e

wat er use so t hat t he per i od of summer soi l

drought i s mi ni mi zed ( Specht 1972) ; water i s t hen

avai l abl e thr oughout t he summer t o suppor t

phot osynt hesi s and growt h i n summer . I n some

r egi ons of hi gh annual pr eci pi t at i on i n Sout h

Af r i ca and Austr al i a, t he soi l s are ei t her rocky

and sandy or ar e under l ai n by a hardpan, so

peri odi c dr ought i s possi bl e i n spi t e of hi gh

r ai nf al l .

The obj ect i ve of t hi s paper i s t o r evi ew

concept s of nut r i ent ai d wat er r el ati ons i n

medi t err anean- t ype ecosyst ems, i ndi cate

i nt eract i ons bet ween t he t wo, and suggest

possi bl e needs f or f ut ur e resear ch.

SOI L- PLANT NUTRI ENT RELATI ONS I N

MEDI TERRANEAN- TYPE ECOSYSTEMS

The r ol e of nut r i ent s, espec i al l y phosphor us,

i n de te rmi ni ng the vegeta t i on i n

medi t er r anean- t ype ecosyst ems has been emphasi zed

i n Aust r al i a and Sout h Af r i ca ( Kr uger 1979,

Specht 1979) . Specht ( 1979) argues that

nut r i ent s , rather t han l i ght or soi l moi sture,

cause successi on i n medi t err anean- t ype

ecosyst ems. I n South Aust r al i a, t he her baceous

component i n heat h i ncreased af t er f ert i l i z i ngwi t h phosphorus (Specht 1963) . I n Cal i f orni a,

f ert i l i z i ng wi t h ni t r ogen ai d wi t h ni t rogen pl us

phosphorus i ncr eased shrub and her b gr owt h.

Fer t i l i zi ng wi t h phosphor us al one had no eff ect

( Hel l mer s and ot hers 1955, Kummer ow unpubl i shed

da ta , Mi l l e r unpubl i shed dat a ) . Ni t r ogen

f i xat i on by Ceanot hus speci es may be i mpor t ant i n

nort hern Cal i f orni a ( Del wi che and ot her s 1965,

Gr ay and Schl esi nger 1981) ai d may i ncr ease

Ceanot hus abundance on ni t r ogen poor s i t es. But

i n mature chaparr al i n sout hern Cal i f orni a


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ni t rogen f i xat i on by C. greggi i i s negl i gi bl e

( Kummer ow and ot hers 19786) . Chr i st ensen and

Mul l er ( 1975a) concl uded t hat nut r i ent s enhanced

seedl i ng survi val but not seed ger mi nat i on. They

al so showed t hat ni t r ate was washed f r om t he

canopy wi t h t he f i rst ra i n i n t he fa l l and t hat ,

f ol l owi ng f i r e, nut r i ent s wer e most avai l abl e

near t he soi l sur f ace. The ni t r at e washed i nt o

t he soi l i n t he f al l i s subj ect t o l eachi ng by

t he wi nter r ai ns bef ore r oot growt h and ni t r ogen

upt ake begi n. I n the chaparr al r oot gr owt h

occur s af t er Febr uar y and ni t r ogen upt ake occurs

i n Mar ch and Apr i l ( Kummer ow and ot hers 1978b,

Mooney ai d Rundel 1979, Shaver 1981) . The soi l

chemi st r y af f ecti ng l eachi ng i s unknown i n

chapar r al . Ni t r i f i cat i on occurs i n chapar r al

soi l s ( Mari on and other s 1981) .

The f ew exper i ment s t hat exi st on spec i es

i nt er acti ons i n chapar r al i ndi cat e compet i t i on

f or nut r i ent s . I n a st and composed mai nl y of

C. gr eggi i and A. f asci cul at um, el i mi nat i ng al l

A. f asci cul at um i ncreased her b pr oducti on, but

el i mi nat i ng C. gr eggi i and l eavi ng

A. f asci cul atum gave no change i n her b

pr oduc t i on. El i mi nat i ng C. gr eggi i i nc reasedA. f asci cul at um pr oducti on sl i ght l y but decr eased

t he growt h of i ndi vi dual shoot s ( Kummerow

unpubl i shed data). I n f er t i l i zer experi ment s,

ni t r ogen addi t i on al so i ncr eased shrub pr oduct i on

but decr eased t he i ndi vi dual shoot gr owt h

( Kummerow et al . unpubl i shed dat a) . These

exper i ment s t aken t ogether i ndi cat e t hat hi gher

avai l abl e ni t r ogen, ei ther f romf ert i l i zat i on or

f r omel i mi nat i ng compet i t ors, i ncreases

product i on not by i ncreased shoot growt h but by

i ncreased number s of i ndi vi dual shoots per square

met er . Addi t i onal l y, i t appear s that C. gr eggi i

may suppress t he growt h of A f asci cul atum by

more ef f ect i ve ni t r ogen capt ur e, whi l e the

opposi t e does not appear t o occur . The l att erconcl usi on i s consi st ent wi t h a hi gher ni t r ogen

capture abi l i t y of C. greggi i re l at i ve to

A. f asci cul atum ( Zi nke 1977, Mi l l er 1981) but was

unexpect ed because Ceanot hus s peci es can f i x

ni t r ogen under some condi t i ons ( Del wi che and

other s 1965, Cr ay ai d Schl esi nger i n press).

Because of t hei r capaci t y to f i x ni t r ogen,

Ceanot hus speci es coul d be poor at t aki ng up

mi ner al i zed ni t r ogen. Adenostoma f asci cul atum

t ends t o occur on l ow ni t r ogen si t es ( Zi nke 1977,

Mari on ai d others 1981) .

SOI L- PLANT WATER RELATI ONS I N MEDI TERRANEAN TYPE

ECOSYSTEMS

The annual pat t er n of soi l dr ought and ai r

t emperatur e al ong an el evati onal t r ansect f r om 0

t o 2 000 m i n sout hern Cal i f orni a was cal cul ated

f r omt he annual cour ses of pr eci pi t at i on and

pot ent i al evapot r anspi r at i on (Mi l l er 1979) . Such

a pat t er n was post ul at ed by Mooney and ot hers

( 1972) and Mooney and Dunn ( 1970a, b) . Xyl em

press ure pot ent i al s, whi ch were measur ed t o check

t he cal cul at i ons ( Pool e and Mi l l er 1981) ,

decr eased ear l i er i n the summer at t he coast al

and deser t edges of t he chapar r al and l ater

t oward t he cent er of t he chapar r al . Pool e and

Mi l l er ( 1975) showed t hat xyl empr essur e

pot ent i al s of Rhus s pp. and Heter omel es

ar but i f ol i a decreased ear l i er at t he coast t han

i n t he cent er of chaparr al . The patt ern of

dryi ng was af f ected by t he veget ati on cover

( Mi l l er ai d Pool e 1980) . At t he edges of t he

di st r i but i on, wat er use was about 200 mm/ yr per

uni t l eaf ar ea i ndex ( A1) whi ch occur r ed wi t h

pr eci pi t ati on of about 400 mm/ yr. Soi l

evaporati on ai d i nt ercept i on l osses account f or

t he r emai nder of t he pr eci pi t ati on. Wi t h hi gher

pr eci pi t at i on t he l eaf ar ea i ndex i ncreases unt i l

t he resul t i ng tr anspi rat i on r at e decr eases t o

about 200 mm/ yr / A1 Wi t hout di st urbance,

chapar r al vegetat i on shoul d devel op unt i l t he

water use per uni t l eaf area and the dur ati on of

t he summer s oi l drought are si mi l ar t hroughout

t he di st r i but i on of t he chapar r al . The r esul t i ng

per i od of summer drought shoul d be about 3 months

l ong. Thi s hypot hesi s i s consi st ent wi t h the

pat t erns of wat er and soi l drought measur ed under

t he vegetat i on of pol e- ai d equator - f aci ng sl opes

at Echo Val l ey (Mi l l er and Pool e 1979; Ng and

Mi l l er 1980) and wi t h t he patt ern of sever al l eafpr oper t i es ( Pool e and Mi l l er 1981) .

A pat t ern of moder at e wat er use woul d al l ow

suff i ci ent water t hr oughout t he dr ought peri od

f or photosynt hesi s t o off set mai ntenance

r espi r ati on and al l ow f or gr owt h (Specht

1972a, b). Wal t er ( 1973) poi nted out t he evenness

of water pot ent i al s i n deep r oot ed evergr een

shrubs i n medi t err anean t ype r egi ons. These

f i ndi ngs ar e consi st ent wi t h t he patt ern of wat er

use on t he equat or- f aci ng sl ope at Echo Val l ey

( Ng and Mi l l er 1980) whi ch was domi nated by a

s i ngl e speci es, A. f asci cul atum, wi t h t he patt ern

of wat er use i n Q. dumosa and R. ovat a, ai d wi t h

t he patt ern of water use i n the Chi l ean shr ubs.Rhus ovat a al so has a hi gh temper at ure

r equi r ement f or growt h, si mi l ar t o Aust r al i an

shrubs ( Specht 1969a, b). The Chi l ean shr ubs

appear t o have l ow t emper at ure r equi r ement s f or

growt h ( J acobson and ot hers 1981) . Specht' s

suggesti on i s not consi st ent wi t h t he patt ern of

soi l moi st ur e on t he pol e- f aci ng sl ope whi ch i s

domi nat ed by sever al evergr een speci es i ncl udi ng

A. gl auca and C. gr eggi i . Thus, t he patt erns of

wat er use must he vi ewed i n t he context of

var i ous physi ol ogi cal charact er i st i cs and t he

f l oral hi story of t he area. The Austr al i an

medi t er r anean veget at i on has no cool t emper at e

speci es, but such speci es are present i n the

chapar r al ai d mator r al because of t he mi grat i ons

of t he f l ora dur i ng t he Pl ei st ocene ( Axel r od and

Raven 1978; Sol bri g and ot her s 1977) . The need

f or conservi ng water i s more i mport ant f or

speci es wi t h hi gh t emper at ure r equi r ement s f or

growt h.

I n Cal i f orni an chaparr al , t ranspi rat i on i n t he

evergreen shr ubs var i ed seasonal l y (Mi l l er and

Pool e 1979) . Al t hough l eaf conduct ances were

hi gh i n wi nt er, t r anspi r ati on was l ow because net

r adi ati on was l ow and vapor densi t y defi ci t s were

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smal l . I n t he spr i ng, t r anspi r at i on i ncreased

because of i ncr eased dayl engt h, si nce l eaf

conductances and vapor densi t y def i ci t s were

near l y constant . I n J une and J ul y, t ranspi r at i on

decr eased because l eaf conduct ances decr eased,

even t hough vapor densi t y defi ci t s i ncr eased.

Ar ct ost aphyl os gl auca showed a compl ete cessati on

of t r anspi r ati on f or al most 2. 5 mont hs. Rhus

ovata, H. arbut i f ol i a, and C. greggi i showed no

t r anspi r ati on f or about 1 mont h. Si mi l ar annual

patt erns were shown f or heat h i n Sout h Austr al i a

( Specht 1957a). I n mature shrubs t r anspi r ati on

dur i ng spri ng was 0. 7- 2. 0 mm day- 1

m- 2

of l eaf

area. Annual water use on a square meter of l eaf

basi s was 150- 190 mm/ yr f r om A. f asci cul atum,

145- 195 f r omC. gr eggi i , 280- 290 f r omA. gl auca,

and 127 f r om R. ovata ( Mi l l er and Pool e 1979).

Sever al set s of measurement s and cal cul ati ons

i ndi cat e that chami se chaparr al , gr assl ands, and

bar e soi l l ose wat er si mi l ar l y whi l e mi xed

chapar r al l oses more water ( Shachori and Mi chael i

1965, Mi l l er and Pool e 1979, Mi l l er and St oner

1979, Ng and Mi l l er 1980, Pat r i c unpubl i shed

dat a) . I n si mul at i ons tr anspi r at i onal wat er l ossi ncreased wi t h fol i age ar ea. Soi l evapor at i on

decr eased wi t h f ol i age ar ea and was 200- 300 mm/ yr

i n sout her n Cal i f orni a and about 200 mm/ yr i n

cent ral Chi l e. Tot al evapot ranspi rat i on f r om the

veget ati on and soi l i ncr eased wi t h f ol i age area

i ndex i n speci es whi ch had hi gh tr anspi r ati on

r at es but r emai ned constant i n speci es whi ch had

moderate or l ow t r anspi r ati on r ates. I n t hese

l at t er speci es i ncreased tr anspi rat i onal l osses

wer e compensated by decr eased soi l evapor at i on.

Ni t r ogen r el ease decr eased as f ol i age area

i ncr eased, because t he addi t i onal f ol i age area

i ncr eased t r anspi r ati on whi ch decreased the

avai l abl e soi l moi st ur e and t heref ore the l engt h

of t he decomposi t i on season.

Wi t h rel at i vel y l ow preci pi t at i on

( 550 mm/ yr) water

i s l ost by drai nage; t ranspi rat i on i s i ncreased

wi t h hi gher l eaf conduct ances; t he l engt h of t he

dr ought i s short . Leaf wi dt h, i ncl i nat i on, and

col or can be more var i abl e wi t hout aff ect i ng

wat er l oss. At i nt er medi at e pr eci pi t at i on l evel s

( 400- 550 mm/ yr ) t he composi t i on of t he veget at i on

changes t he l ength of t he soi l drought by changes

i n t he abundance of speci es wi t h di f f erent l eaf

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conduct ances and di f f erent l eaf area i ndi ces.

The t r anspi r at i on: pr eci pi t at i on r at i o i s

cont r ol l ed by t he veget ati on composi t i on and can

be rel at i vel y hi gh.

The expect ed t r ends i n wat er r el at i ons occur

i n chaparr al and matorr al speci es ( t abl e 1) .

Maxi mum l eaf conduct ances of Cal i f orni an speci es

arr anged f r om hi ghest t o l owest were:

A. cal i f orni ca, Sal vi a api ana, A. gl auca,

C. gr eggi i , A. f asci cul atum, Q. dumosa, and

R. ovata. The sequence of speci es was si mi l ar

f or t he mi ni mum xyl em pr essur e pot ent i al s , f or

t he dur at i on of l ow pr essur e potent i al s, and the

var i abi l i t y of pr essur e potent i al s through t he

year. Osmoti c concent r ati ons at t ur gi di t y were

s i mi l ar ai d moderate , r angi ng f r om - 2. 0 t o

- 3. 0 MPa. The depth of r oot i ng probabl y al so

i ncreases i n t he same sequence. Ar t emi si a

cal i f orni ca, S. api ana, C. greggi i , and A. gl auca

are r ecogni zed as shal l ow r oot ed, whi l e Q. dumosa

and R. ovat a are t hought t o be deep r oot ed

( Hel l mer s and ot hers 1955; Kummer ow and ot hers i n

press) . The sequence of speci es al so segr egat e

obl i gate seeders ai d spr out i ng shr ubs. The

sequence occur s al ong a gr adi ent of i ncreasi ngannual preci pi t at i on. Di f f erent pat terns of

r epr oducti on may r ei nf orce t he patt erns of

water - use char acteri st i cs. Seedl i ngs and

r esprout s have di f f erent wat er envi r onment s when

young. Schl esi nger and Gi l l ( 1980) showed l ower

wat er potenti al s dur i ng t he summer i n seedl i ngs

t han i n matur e i ndi vi dual s of Ceanot hus

megacarpus. Radosevi ch and ot her s ( 1977)

i ndi cat ed t hat r espr out s of A. f asci cul at um

gener al l y had hi gher water potent i al s t han t he

unbur ned cont r ol vegetat i on. The hi gher soi l

moi st ure under Banksi a ornat a ( Specht 19576) and

decr eased water use wi t h reduced st em densi t i es

of Acaci a aneura (Pr essl and 1976) appear t o be

consi st ent wi t h t he expect ed i nter act i on bet weenl eaf ar ea, l eaf conductance, ai d wat er l oss.

The Chi l ean spec i es, ar r anged by maxi mum l eaf

conduct ance f r omhi ghest ( about 0. 5 cm/ s) t o

l owes t ( about 0. 15 cm/ s ) , are S. gi l l i es i i ,

T. t r i ner vi s, C. odor i f er a, Q. saponar i a,

C. al ba, and L. caust i ca. The sequence was

si mi l ar f or t he l owest xyl em pr essur e pot ent i al s

measur ed but was not as consi st ent as wi t h the

Cal i f orni an speci es. Root i ng depth may be

si mi l ar l y ar r ayed i n t he Chi l ean speci es (Avi l a

and ot her s 1975, Gi l i ber t o and Estay 1978). The

sequence i s not as cl ear l y rel ated t o

r eproducti ve pat t er ns as wi t h the Cal i f or ni an

shr ubs.

The maxi mum l eaf ar ea i ndex whi ch coul d be

mai nt ai ned wi t h di f f er ent annual pr eci pi t at i on

amounts was est i mated by si mul ati ons ( Mi l l er

1981) . These l eaf area i ndi ces i ncr eased as

preci pi t ati on i ncreased t o about 400 mm/ yr wi t h

t he Cal i f orni an shrubs ai d to 350 mm/ yr wi t h the

Chi l ean shr ubs. The cal cul ated st eady stat e l eaf

area i ndi ces were si mi l ar t o those measured i n

t he f i el d ( Mi l l er a i d Pool e 1980) .

I NTERACTI ONS BETWEEN NUTRI ENTS AND WATER

The avai l abl e nut r i ent s and wat er and t he r at e

of t urnover of l eaves and st ems af f ect s t he

bi omass t hat can be suppor t ed. The st eady st at e

bi omass ( B) can be expr essed i n terms of t he

preci pi ta t i on (Ppt ) , t r anspi rat i on ef f i c i ency

( Tr / Ppt ) , wat er- use ef f i c i ency ( PS/ Tr ) ,

mai ntenance and gr owt h respi r ator y cost s ( r m, r g) and l eaf l ongevi t y ( ) by

B = ( Ppt ) ( Tr/ Ppt ) ( PS/ Tr ) / ( r m + r g ) Eq. 1

Annual preci pi t ati on and ni t r ogen t aken up by

t he veget at i on shoul d be i nt er r el at ed. I n the

st eady stat e ni t r ogen t aken up must equal t hat

l ost as pl ant part s ar e shed. Thus,

B = ( Nup) / [ ( Nd) ] Eq. 2

wher e Nup i s t he ni t r ogen t aken up, and Nd i s the

ni t r ogen cont ent of pl ant part s at deat h.

Equat i ons 1 and 2 i ndi cate t hat t he st eady st ate

bi omass shoul d i ncrease by 400- 500 g/ m2 f or every

100 mm/ yr i ncrease i n annual preci pi t ati on and by

about 400 g/ m2 f or every addi t i onal g N m- 2 yr - 1t aken up. I ncr easi ng l eaf l ongevi t i es more than

2 year s have smal l er ef f ect s on t he st eady st ate

bi omass t han i ncreasi ng l eaf l ongevi t i es f r om

1 to 2 year s. Wi t hi n a pr eci pi t at i on regi me l eaf

l ongevi t y shoul d i ncr ease i n accor dance wi t h

ni t r ogen l i mi t ati on because turnover r ate i s more

cl osel y rel ated t o ni t r ogen upt ake t han t o

preci pi ta t i on.

I nter acti ons bet ween water and ni t r ogen

avai l abi l i t y can be cal cul at ed. A gram of

ni t r ogen t aken up and i ncor por ated i nto

abovegr ound t i ssue yi el ds an i ncrement of about

166 g dr y wei ght / g N of new bi omass. Leaf area

i s i ncreased by about 0. 004 m2

1/ g dry wei ghtal t hough some of t he new bi omass i s i n st ems.

Thi s i ncr ement of l eaf ar ea i ncr eases

t r anspi r ati on by about 0. 67 kg day- 1

g- 1

N,

Al l owi ng f or t he dry wei ght and water cost s

i nvol ved i n the gr owt h of t he l eaf area, t he net

i ncr ease i n t r anspi r ati on i s about 0. 33 kg day- 1

g- 1

N. The i ncr eased tr anspi r ati on decr eases t he

l engt h of t he season i n whi ch soi l moi st ur e i s

avai l abl e. The l ength of t he growi ng season

changes wi t h tr anspi r ati on accor di ng to t he

amount of water avai l abl e di vi ded by t he square

of t he dai l y evapot r anspi r at i on rate. Thus, t he

r educt i on i n t he gr owi ng season because of added

ni t r ogen woul d be about 0. 33 x 38 or 12 days per

gr am ni t r ogen t aken up by t he chaparr al i n

sout her n Cal i f orni a and by about 10 days per gr am

ni t r ogen t aken up by t he matorr al i n cent r al

Chi l e. Thi s shor t eni ng of t he gr owi ng season

shoul d reduce gr owt h by about 48 g dr y wei ght m- 2

yr- 1

i n sout her n Cal i f orni a and by 20 g dr y

wei ght m- 2

yr- 1

i n cent ral Chi l e, whi l e the

i ncreased ni t r ogen shoul d i ncrease growt h by

about 166 g dry wei ght . Thus, net growt h shoul d

i ncrease about 118 g dry wei ght / g N t aken up i n

Cal i f orni a and 146 g dry wei ght / g N t aken up i n

328


5/8

Chi l e, even t hough the gr owt h peri od i s l i mi t ed

by temper atur e ai d water .

Long l eaf dur ati on, f r omwhat ever cause,

af f ects t he avai l abi l i t y of ni t rogen. The

presence of l i gneous and her bi vor e def ense

compounds can reduce the qual i t y of t he subst r at e

f or decomposi t i on and mi neral i zati on. The

sel ecti on of evergr een l eaves by the seasonal

patt erns of t emperatur e and water avai l abi l i t y

f avors l eaves of about 1- year dur ati on but does

not necessar i l y f avor l eaves wi t h more t han

1-year durat i on. The ever gr een l eaves shoul d

have st r uct ur al modi f i cat i ons to mai nt ai n

r i gi di t y under water st r ess and to r educe the

i nt ensi t y of wat er st r ess ( Beadl e 1966; Cut l er

and ot hers 1977) . Accor di ng t o heat t r ansf er

t heor y, such l eaves shoul d be ri gi d, nar r ow,

st eepl y i ncl i ned, and l i ght col or ed t o reduce

cel l ul ar di st ort i on, pl ant t emper at ur es, and

tr anspi rat i on rates. Smal l cel l s i ze i s

advantageous ( Cutl er and ot her s 1977) . Leaf

l ongevi t i es may i ncrease wi t h ni t r ogen l i mi t ati on

( Monk 1966) . Al t hough evergreenness caused by

ni t rogen l i mi t at i on does not r equi r e the

adapt ati ons t o survi ve drought ( Beadl e 1966) , t hegener al bi ochemi cal composi t i on of ni t r ogen-

l i mi t ed l eaves may be si mi l ar t o that of water-

l i mi t ed l eaves, resul t i ng i n s i mi l ar scl erophyl l

i ndi ces, whi ch ar e, based on l i gni n, cel l ul ose, and

ni t r ogen cont ent ( Lovel ess 1961). Water

l i mi t at i on creat es a di r ect need f or

scl er ophyl l ous t i ssue, whi l e t he ni t r ogen or

phosphor us l i mi t ati on may reduce prot ei n

f or mati on due to l ow nut r i ent avai l abi l i t y, whi ch

may i ncr ease cel l ul ose and l i gni n for mati on

because of excess car bohydrat e ( Lovel ess 1961,

Beadl e 1966, Steubi ng and Al ber di 1973) .

Specht and ot her s ( 1981) di scuss t he

seasonal i t y of l eaf gr owt h and l eaf dr op i nAust r al i a and Sout h Af r i ca. Thei r opi ni ons are

si mi l ar t o opi ni ons devel oped i n studi es of

chaparr al and mat or r al i n Cal i f or ni a and Chi l e.

The i ndi cat i ons ar e t hat i f wat er l i mi t s bi omass ,

l eaf drop wi l l f ol l ow l eaf gr owt h, whi ch occurs

i n most evergreen shr ubs i n Cal i f orni a and Chi l e

( Mooney 1977). But i f nutr i ent s l i mi t bi omass

and gr owt h, l eaf drop wi l l be synchr onous wi t h

l eaf growt h, as occurs i n Quer cus sp. and i n

Aust r al i a and Sout h Af r i ca (Specht and Mol l

1981) .

Of t he f i ve medi t err anean r egi ons of t he

worl d, t he medi t err anean r egi on of cent r al Chi l e

i s re l at i vel y nut r i ent r i ch. Vegetat i on i s

cl i mati cal l y sel ected, and l eaf t ur nover r at es

ar e r el at i vel y hi gh. I n sout her n Cal i f or ni a and

sout her n Europe, soi l s ar e l ess nut r i ent ri ch, but

cl i mat e i s st i l l a str ong sel ect i ve agent ; l eaf

t ur nover i s sl ower t han i n cent r al Chi l e. I n t he

medi t err anean regi ons of Austr al i a and South

Af r i ca wher e ol d, nut r i ent poor soi l s occur , l eaf

t ur nover i s l ower t han i n Cal i f or ni a ( Kr uger

1979, Specht 1979, Mi l l er and ot her s unpubl i shed

dat a) , and t he cl i mat i c ef f ect i s rei nf or ced by

nut r i ent l i mi t at i ons .

I n Sout h Af r i ca, pi nes ar e rapi dl y i nvadi ng

undi st urbed f ynbos, and pi ne pl ant ati ons on

unf er t i l i zed f ynbos soi l s have hi gher

pr oduct i vi t y t han t he nati ve f ynbos or t han t he

pi nes i n thei r nati ve Nort hern Hemi spheri c

habi t ats ( Van der Zel and Kr uger 1975, Hal l and

Boucher 1977) . Rough est i mates i ndi cat e t hat

annual l y t he pi nes t ake up thr ee t i mes t he

ni t r ogen as does t he f ynbos on t he same soi l

( Mi l l er and other s unpubl i shed data) . The

Prot eaceae and Rest i onaceae l ack mycor r hi zal

associ ates ( Lamont 1981) . Exper i ment s wi t h t r ee

seedl i ngs show a near l y 50-f ol d i ncr ease i n

growt h when t he seedl i ngs ar e i nocul at ed by

mycor r hi zae. Prot eoi d r oot s may merel y

compensate f or t he r educed nut r i ent and wat er

upt ake caused by t he l ack of mycorr hi zae. The

i ntr oduced pi nes have mycor r hi zae. I n Sout h

Af r i ca at l east , t he appar ent nut r i ent

i mpoveri shment may not be due to t he soi l

suppl yi ng abi l i t y but t o the pl ant upt ake

abi l i t y.

The l ow pr oduct i on i n Sout h Af r i can f ynbos and

Aust r al i an heat h may al so be due to hi gh

t emper at ure r equi r ement s f or growt h ( Specht1972) . Because t hese t emper at ures occur dur i ng

t he summer drought , t he gr owi ng season i s

sever el y tr uncat ed. I n bot h count r i es t he f l ora

i n the medi t err anean r egi ons has evol ved f r om a

t r opi cal f l ora, whi ch has not been i nvaded by

mor e pol ar el ement s. I n Chi l e, Cal i f orni a, and

t he Medi t er r anean Sea regi ons, a more pol ar

f l oral el ement wi t h cool er t emperatur e

r equi r ement s f or growt h has mi xed i nt o t he

veget at i on (Raven 1973, Axel r od and Raven 1978) .

Temper at ur e l i mi t at i ons on gr owt h i n Sout h Af r i ca

and Austr al i a coul d have al l owed excessi ve

l eachi ng of nut r i ent s resul t i ng i n t he cur r ent

nut r i ent i mpover i shment of medi t err anean- t ype

ecosyst ems i n t hese countr i es. The Sout her nHemi sphere medi t err anean r egi ons r ecei ve l ess

spri ng preci pi t ati on t han t he Nort her n Hemi sphere

medi t err anean r egi ons, whi ch speeds t he onset of

summer drought i n t he Sout her n Hemi sphere ( Mi l l er

1981) . The l ow producti on i n Sout h Af r i can and

Aust r al i an medi t er r anean r egi ons may al so be due

t o hi gh cl oudi ness and l ow sol ar i r r adi ance

dur i ng t he wi nter whi ch r educe photosynt het i c

r at es. A l i mi t at i on on photosynt hesi s by sol ar

i r r adi ance was i ndi cat ed f or cent r al Chi l e

( Mi l l er 1981) . Thus, t he pl ant s i n the Sout hern

Hemi spher e may ent er t he spr i ng wi t h l ower

carbohydr ate r eser ves and l ower growt h pot ent i al .

RESEARCH NEEDS

I n spi t e of t he r ecogni t i on of di vergent

causes of vegetat i on f orm i n medi t err anean- t ype

ecosyst ems, f unct i onal measurement s of nut r i ent

and water avai l abi l i t y have not been car r i ed out

wi t h i dent i cal t echni ques. A di r ect f uncti onal

compari son i s needed. St ati c comparat i ve soi l

st ati st i cs, whi ch are now becomi ng avai l abl e, do

not show gr eat di f f erences i n soi l organi c matt er

content , t ot al ni t rogen, avai l abl e ni t rogen,

329


6/8

t otal phosphorus, avai l abl e phosphorus, percent

base sat urat i on, and pH bet ween Sout h Af r i ca,

Aust r al i a, Cal i f or ni a, and Chi l e (Thr ower and

Br adbur y 1977, Mi l l er et al . 1977, Kr uger 1979,

Boone unpubl i shed dat a) . Ear l i er measur ement s of

avai l abl e ni t r ogen and phosphorus i n Cal i f orni a

and Chi l e, whi ch ar e of t en ci t ed i n compari ng

medi t err anean- t ype r egi ons, are r ej ected because

of t he l ength of t i me bet ween col l ect i on and

processi ng of t he sampl es.

Di r ect compar abl e measur ement s on soi l

nut r i ent suppl yi ng power and pl ant upt ake abi l i t y

are needed t o def i ne t he cont r ol s on t he

composi t i on and f orm of medi t err anean- t ype

ecosyst ems i n the f i ve medi t err anean regi ons of

t he wor l d. I n addi t i on, a synt hesi s of t hese

measurements and exi st i ng data i s needed and

shoul d l ead t o a quant i f i cat i on of nut r i ent

cycl i ng, i t s cont r ol , and an expl anat i on of how

nut r i ent cycl i ng pr ocesses devi at e i n

medi t er r anean- t ype ecosyst ems. Such a synt hesi s

i s t i mel y. Much descr i pt i ve i nf ormati on has been

col l ect ed and i s bei ng publ i shed ( Specht 1979,

Kr uger 1981, Mi l l er 1981) . Some f unct i onal

r el ati ons have been est abl i shed f or s omemedi t err anean- t ype ecosyst ems and col l ated i n

ori gi nal and revi ew papers ( Kr uger and Si egf r i ed

1981, Mi l l er 1981) . The communi cat i on and

cooper ati on among i nvest i gat ors i n t he

medi t er r anean- t ype ecosyst ems i s good. The

synt hesi s shoul d cl ar i f y whet her t he si mi l ar i t y

i n veget at i on f orm i s onl y coi nci dent l y

associ ated wi t h t he medi t err anean- t ype cl i mat e

but i s caused by di f f erences i n soi l and cl i mat e

i n t he f i ve medi t err anean r egi ons.

LI TERATURE CI TED

Avi l a, G. ; Al j ar o, M. ; Ar aya, S. ; Mont enegr o, G.

The seasonal cambi um act i vi t y of Chi l ean andCal i f orni an shr ubs. Am. J . Bot. 62: 473- 478;

1975.

Axel r od, D. I . ; Raven P. H. Late Cr etaceous and

Ter t i ar y veget at i on hi st or y of Af r i ca. I n:

Werger, M. J . A. , ed. Bi ogeography and ecol ogy

of sout her n Af r i ca. The Hague, Nether l ands:

Dr . W. J unk Publ i shers; 1978: 77- 130.

Beadl e, N. C. W. Soi l phosphat e and t he

del i mi t ati on of pl ant communi t i es i n east ern

Aust r al i a. Ecol ogy 35: 370- 375; 1954.

Beadl e, N. C. W. Soi l phosphate and i t s r ol e i n

mol di ng segment s of t he Austr al i an f l ora and

veget ati on, wi t h speci al r ef erence to

xer omorphy ai d scl erophyl l y . Ecol ogy

47: 992- 1007; 1966.

Bi ngham, G. E. ; Coyne, P. I . A port abl e,

t emperat ur e-cont r ol l ed, st eadyst ate porometer

f or f i el d measur ements of t r anspi r ati on and

photosynthesi s. Phot osyntheti ca 11: 148- 160;

1977.

Chang, C. Cl i mate and agr i cul t ur e, an ecol ogi cal

sur vey. Chi cago: Al di ne Publ . Co. ; 1968. 304

PP.

Chr i stensen, N. L . ; Mul l er , C. H. Ef f ects of

f i re on f actors cont rol l i ng pl ant growt h i n

Adenost oma chapar r al . Ecol . Monogr . 45: 29- 55;

1975.

Cut l er, J . M. ; Rai ns, D. W. ; Loomi s, R. S. The

i mpor t ance of cel l s i ze i n t he wat er r el ati ons

of pl ant s. Physi ol . Pl ant . 40: 255- 260; 1977.

Day, J . ( ed. ) . Nut r i ent s i n medi t er r anean type

ecosyst ems. Pr oceedi ngs of t he MEDCO wor kshop;

1980 September 24- 26; Pret ori a: Republ i c of

Sout h Af r i ca; CSI R; 1981.

Day, J . ; Si egf r i ed, W. R. ; Louw, G. N. ; J ar man,

M. L. , eds. Fynbos ecol ogy: A pr el i mi nary

synt hesi s. Pr et or i a, Republ i c of Sout h Af r i ca:

CSI R, S. Af r i can Nat . Sci . Pr ogr . Rept . No. 40.

Deacon, H. J . The compar at i ve evol uti on of

medi t er r anean- t ype ecosyst em: A souther n

per spect i ve. I n: Pr oceedi ngs of t he t hi r d

i nter nat i onal conf erence on medi t err anean- t ype

ecosyst ems; 1980 Sept ember 22- 23; Stel l enbosch,

Republ i c of Sout h Af r i ca; 1981.

Del wi che, C. C. ; Zi nke, P. J . ; J ohnson, C. M.

Ni t r ogen f i xat i on by Ceanothus. Pl ant Physi ol .

40: 1045- 1047; 1965.

F i scher, R. A. ; Turner, N. C. Pl ant pr oduct i v i t y

i n t he ari d and semi ari d zones. Annu. Rev.

Pl ant Physi ol . 29: 277- 317; 1978.

Gr ay, J . T. ; Schl esi nger , W. H. Nut r i ent cycl i ng

i n medi t err anean- t ype ecosystems. I n:

Mi l l er, P. C. , ed. Resour ce use by chapar r aland mator r al : A compar i son of veget ati on

f unct i on i n two medi t err anean- t ype ecosyst ems.

New York- Hei del ber g- Ber l i n: Spr i nger - Verl ag;

1981: i n press.

Gi l i bert o, J . ; Estay, H. Seasonal wat er str ess

i n sel ect ed shrub speci es i n t he medi t err anean

r egi on of cent r al Chi l e. Bot . Gaz. 139: 236-

240; 1978.

Hal l , A. V. ; Boucher, C. The threat posed by

al i en veget at i on t o t he Cape f l ora. I n:

Pr oceedi ngs of t he second nat i onal weeds

conf erence; St el l enbosch, Republ i c of South

Af r i ca; 1977: 35- 46.

Heddl e, E. M. ; Specht , R. L. Dark I sl and heat h

( Ni nety - Mi l e Pl ai n, South Aust r al i a) . VI I I .The ef f ect of f er t i l i zer s on composi t i on and

growt h, 1950- 1972. Aust . J . Bot. 23: 151-164;

1975.

Hel l mers, H. ; Bonner, J . F . ; Kel l eher J . M. Soi l

f ert i l i t y: A water shed management pr obl em i n

t he San Gabr i el Mountai ns of sout her n

Cal i f orni a. Soi l Sci . 80: 189- 197; 1955.

Hut ni k, R. J . ; Davi s, G. , eds. Ecol ogy and

r ecl amat i on of devast ated l and. Pr oceedi ngs of

t he i nter nat i onal symposi um on ecol ogy and

r eveget ati on of dr ast i cal l y di st ur bed areas.

Uni ver si t y Par k, Pa. : New Yor k- Par i s- London:

Gordon and Br each; Vol . 1.

J acobson, M. B. ; St oner , W. A. ; Ri char ds, S. P.

Model s of pl ant and soi l pr ocesses. I n:

Mi l l er , P. C. , ed. Resour ce use by chapar r al

and mator r al . New York- Hei del ber g- Berl i n:

Spr i nger- Verl ag; 1981.

Kr uger, F. J . Sout h Af r i can heat h l ands. I n:

Specht , R. L. , ed. Heat hl ands ai d r el ated

shr ubl ands. Par t A: Descri pt i ve st udi es.

Amst erdam- Oxf ord- New Yor k: El sevi er Sci enti f i c

Publ . Co. ; 1975: 19-80.

Kruger, F . J . St ruct ural and f unct i onal

char acter i st i cs of medi t er r anean- t ype pl ant s.

330


7/8

331

I n: Pr oceedi ngs of t he t hi r d i nt er nat i onal

conf er ence on medi t er r anean- t ype ecosyst ems;

1980 September 22- 23; Stel l enbosch, Republ i c of

Sout h Af r i ca; 1981a.

Kr uger, F. J . Pl ant communi t y di ver si t y and

dynami cs i n r el at i on t o f i r e. I n: Proceedi ngs

of t he thi r d i nt er nati onal conf er ence on

medi t er r anean- t ype ecosyst ems; 1980

September 22- 23; St el l enbosch, Republ i c of

Sout h Af r i ca; 19816.

Kruger, F . J . ; Si egf r i ed, W. R. , eds. Nut r i ents

as det ermi nants of t he st r uctur e and

f unct i oni ng of medi t err anean t ype ecosystems.

New York- Hei del ber g- Ber l i n: Spr i nger - Verl ag;

1981.

Kummer ow, J . ; Kr ause, D. ; J ow, W. Seasonal

changes of f i ne root densi t y i n the sout her n

Cal i f orni a chapar r al . 0ecol ogi a 37: 201- 212;

1978.

Lamont, B. The ef f ect of soi l nut r i ent s on t he

pr oduct i on of pr oteoi d root s by Hakea speci es.

Aust . J . Bot . 20: 27- 40; 1972a.

Lamont , B. The mor phol ogy and anat omy of

pr oteoi d r oot s i n t he genus Hakea. Aust . J .

Bot. 20: 155- 174; 1972b.

Lamont , B. Fact or s af f ecti ng t he di st r i but i on ofpr oteoi d root s wi t hi n the root systems of t wo

Hakea speci es. Aust. J . Bot. 21: 165- 187; 1973.

Lamont, B. Speci al i zed r oot s of non- symbi oti c

or i gi n i n heat hl ands. I n: Specht , R. L . , ed.

Heat hl ands and r el ated shr ubl ands of t he worl d.

Amst erdam: B. El sevi er; 1980.

Lamont, B. B. Speci al i zed r oot s of non- symbi oti c

or i gi n i n heat hl ands. I n: Specht , R. L . , ed.

heathl and ai d r el ated shr ubl ands. Ecosyst ems of

t he Wor l d. Vol . 9. Amst erdam- Oxf ord- New York:

El sevi er Sci ent i f i c Publ . Co. ; 1981.

Lamont, B. B. St r ategi es f or maxi mi zi ng nut r i ent

upt ake i n medi t err anean- t ype ecosyst ems. I n:

Pr oceedi ngs of t he t hi r d i nt ernat i onal

conf er ence on medi t er r anean- t ype ecosyst ems;1980 September 22- 23; Stel l enbosch, Republ i c of


Lovel ess, A. R. A nut r i t i onal i nt erpretat i on of

scl erophyl l y based on di f f erences i n t he

chemi cal composi t i on of scl erophyl l ous and

mesophyt i c l eaves. Ann. Bot. 25: 168- 184; 1961.

Mari on, G. M. ; Kummerow, J . ; Mi l l er, P. C.

Pr edi cti ng ni t r ogen mi ner al i zat i on i n chapar r al

soi l s . Soi l Sci . Soc. Am. J . i n press; 1981.

Mart i n, H. A. ; Specht , R. L. Ar e mesi c

communi t i es l ess dr ought r esi st ant ? A st udy of

moi st ure rel at i onshi ps i n dr y scl er ophyl l

f orest at I ngl ewood, Sout h Austr al i a. Aust. J .

Rot. 10: 106- 118; 1962.

Mi l l er , P. C. Quant i t at i ve pl ant ecol ogy. I n:

Horn, D. ; St ai rs , G. R. ; Mi t chel l , R. D. , eds.

Anal ysi s of ecosyst ems. Col umbus: Ohi o Stat e

Uni v. Pr ess; 1979: 179- 232.

Mi l l er, P. C. ; Mooney, H. A. The or i gi n and

st r uctur e of Ameri can ari d- zone ecosyst ems.

The pr oducer s: I nt er act i ons bet ween

envi r onment , f orm, and f unct i on. Proceedi ngs

of t he f i r st i nt ernat i onal congr ess of ecol ogy;

The Hague, Net her l ands; 1974: 201- 209.

Mi l l er , P. C. ; Pool e, D. K. Pat t erns of wat er

use by shr ubs i n sout her n Cal i f or ni a. For .

Sci . 25: 84- 98; 1979.

Mi l l er, P. C. ; St oner , W. A. Canopy str ucture

and envi r onment al i nt er acti ons. I n:

Sol br i g, 0. ; J ai n, S. ; J ohnson, G. B. ;

Raven, P. H. , eds. Pl ant popul ati on bi ol ogy.

New Yor k: Col umbi a Uni v. Press; 1979: 163-173.

Mi l l er , P. C. ; Bradbury, D. E. ; Haj ek, E. ; La

Marche, V. ; Thr ower, N. J . W. Past and pr esent

envi r onment . I n: Mooney, H. A. , ed.

Conver gent evol ut i on i n Chi l e and Cal i f or ni a

medi t err anean cl i mate ecosyst ems. Str oudsbur g,

Pa: Dowden, Hutchi nson & Ross; 1977: 27- 72.

Mi l l er , P. C. ; St oner, W. A. : Ti eszen, L . L . A

model of st and phot osynt hesi s f or t he wet

meadow t undr a at Bar r ow, Al aska. Al aska

57: 411- 430; 1976.

Mol l , E. J . ; Specht , R. L . , Manders; P. T. The

r ol e of woody under ground part s i n sur vi val and

gr owt h. I n: Pr oceedi ngs of t he thi r d




Monk, C. D. An ecol ogi cal si gni f i cance of

ever greenness. Ecol ogy 47: 504- 505; 1966.

Mooney, H. A. , ed. Conver gent evol uti on i n Chi l e

and Cal i f orni a medi t err anean cl i mate

ecosyst ems. St r oudsbur g, Pa. : Dowden,Hutchi nson & Ross; 1977. 224 p.

Mooney, H. A. ; Dunn, E. L. Conver gent evol uti on

of medi t err anean cl i mate evergreen scl erophyl l

shrubs. Evol uti on 24: 292- 303; 1970a.

Mooney, H. A. ; Dunn, E. L. Photosynt het i c

syst ems of medi t er r anean cl i mat e shrubs and

t r ees of Cal i f or ni a and Chi l e. Am. Nat .

104: 447- 453; 19706.

Mooney, H. A. ; Rundel , P. W. Nut r i ent r el ati ons

of t he evergr een shr ub, Adenost oma

f asci cul at um, i n the Cal i f orni a chaparr al .

Bot. Gaz. 140: 109- 113; 1979.

Mooney, H. A. ; Dunn, E. L. ; Shr opshi r e, F. ; Song,

L. , J r . Land- use hi story of Cal i f orni a and

Chi l e as r el at ed t o the st r uct ur e of t hescl erophyl l scr ub veget ati ons. Madr ono

21: 305- 319; 1972.

Ng, E. ; Mi l l er , P. C. Soi l moi s ture re l at i ons i n

sout her n Cal i f or ni a chapar r al . Ecol ogy

61: 98- 107; 1980.

Or shan, G. The medi t er r anean t ype pl ant f orm: A

def i ni t i on. I n: Proceedi ngs of t he t hi rd



Republ i cs of Sout h Af r i ca; 1981.

Pool e, D. K. ; Mi l l er , P. C. Wat er r el at i ons of

sel ect ed speci es of chaparr al and coastal sage

communi t i es. Ecol ogy 56: 1118- 1128; 1975.

Pool e, D. K. ; Mi l l er , P. C. The di s t r i but i on of

pl ant water st r ess and vegetat i on

character i st i cs i n sout hern Cal i f orni a

chaparr al . Am. Mi di . Nat. 105: 32-43; 1981.

Pool e, D. K. ; Robert s , S. W. ; Mi l l er , P. C.

Wate r ut i l i z at i on. I n: Mi l l er , P. C. , ed.

Resour ce use by chapar r al and mat or r al : A

compar i son of vegetat i on f unct i on i n t wo

medi t er r anean t ype ecosyst ems. New

Yor k- Hei del ber g- Ber l i n: Spr i nger - Verl ag;

1981: i n press.

Pr essl and, A. J . Ef f ect of st and densi t y on

water use of mul ga ( Acaci a aneura F. Muel l . )


8/8

332

woodl ands i n southwest ern Queensl and. Aust . J .

Rot. 24: 177- 191; 1976.

Radosevi ch, S. R. ; Conr ad, S. C. ; Adams, D. R.

Regr owt h r esponses of chami se f ol l owi ng f i r e.

I n: Mooney, H. A. ; Conr ad, C. E. , eds.

Proceedi ngs of t he symposi um on t he

envi r onment al consequences of f i r e and f uel

management i n medi t er r anean ecosyst ems; 1977

August 1- 5; Pal o Al t o, CA: U. S. Dept . Agr i c. ,

For . Serv. and U. S. For . Ser v. Gen. Tech.

Rep. WO- 3.

Raven, P. H. The evol uti on of medi t err anean

f l oras. I n: di Cas t r i , F. ; Mooney, H. A. ,

eds. Medi t err anean t ype ecosystems: Or i gi n

and st r uct ur e. New Yor k- Hei del berg- Berl i n:

Spr i nger - Verl ag; 1973: 213- 224.

Read, D. J . ; Mi t chel l , D. T. Decomposi t i on and

mi neral i zati on pr ocesses i n medi t err anean-t ype

ecosyst ems and i n heat hl ands of si mi l ar

st r uct ur e. I n: Pr oceedi ngs of t he t hi r d




Shachor i , A. Y. ; Mi chael i , A. Wat er yi el ds of

f orest , maqui s, and gr ass cover s i n semi ari d

regi ons. A l i t erature revi ew. I n:Eckar dt, F. D. , ed. Methodol ogy of pl ant

ecophysi ol ogy. Par i s: UNESCO; 1965.

Shaver, G. R. Mi neral nut r i ent and nonst r uct ural

carbon ut i l i z at i on. I n: Mi l l er , P. C. , ed.

Resource use by chapar r al ai d mator r al : A

compar i son of vegetat i on f unct i on i n t wo

medi t er r anean t ype ecosyst ems. New

Yor k- Hei del ber g- Ber l i n: Spr i nger - Ver l ag;

1981: i n press.

Si ms, P. L. ; Si ngh, J . S. The st r ucture and

f unct i on of t en west ern Nort h Ameri can

gr assl ands. I I . I nt r a- seasonal dynami cs i n

pri mary producer compar t ment s. J . Ecol .

66: 547- 572; 1978.

Sol br i g, O. T. ; Cody, M. L . ; Fuent es, E. R. ;Gl anz, W. ; Hunt , J . H. ; Mol denke, A. R. The

or i gi n of t he bi ot a. I n: Mooney, H. A. , ed.

Conver gent evol ut i on i n Chi l e and Cal i f or ni a,

medi t err anean cl i mate ecosyst ems. Str oudsbur g,

Pa. : Dowden, Hutchi nson & Ross; 1977: 13- 26.

Specht, R. L. Dark I sl and heat h ( Ni nety- Mi l e

Pl ai n, Sout h Austr al i a) . I V. Soi l moi sture

patt erns pr oduced by r ai nf al l i nt ercept i on and

st em- f l ow. Aust . J . Bot. 5: 137- 150; 1957a.


Pl ai n, Sout h Aust r al i a) . V. The wat er

r el ati onshi ps i n heath vegetat i on and past ur es

on t he Maki n Sand. Aust . J . Bot. 5: 151- 172;

1957b.


Pl ai n, Sout h Austr al i a) . VI I . The ef f ect of

f er t i l i zer s on composi t i on ai d gr owt h, 1950- 60.

Aust . J . Bot . 11: 67- 94; 1963.

Specht, R. L. A compari son of t he scl erophyl l ous

vegetat i on character i st i c of medi t err anean t ype

cl i mat es i n Fr ance, Cal i f or ni a, and sout her n

Aust r al i a. I . St r ucture, mor phol ogy, and

successi on. Aust . J . Bot. 17: 277-292; 1969a.

Specht, R. L. A compari son of t he scl erophyl l ous

vegetat i on character i st i c of medi t err anean t ype

cl i mat es i n Fr ance, Cal i f or ni a, and sout her n

Aust r al i a. I I . Dry mat t er , energy, and

nut r i ent accumul at i on. Aus t . J . Bot .

17: 293- 308; 19696.

Specht , R. L. Water use by perenni al evergr een

pl ant communi t i es i n Aust r al i a and Papua New

Gui nea. Aust . J . Bot . 20: 273- 299; 1972.

Specht, R. L. , ed. Heat hl ands and rel ated

shr ubl ands. Par t A: Descri pt i ve st udi es.

Amst erdam- Oxf ord- New Yor k: El sevi er Sci enti f i c

Publ i shi ng Co. ; 1979. 498 p.

St eubi ng, L. ; Al ber di , M. The i nf l uence of

phosphorus defi ci ency on t he scl erophyl l y.

Oecol . Pl ant . 8: 211- 218; 1973.

Specht , R. L . ; Mol l , E. J . Nut r i ent s asdet ermi nant s of t he st r uct ur al and f unct i oni ng

of medi t err anean- t ype ecosyst ems. I n:

Proceedi ngs of t he t hi r d i nt er nati onal

conf er ence on medi t er r anean- t ype ecosyst ems;

1980 September 22- 23; Stel l enbosch, Republ i c of


Thr ower , N. J . W. ; Bradbur y, D. E. , eds.

Chi l e- Cal i f or ni a medi t er r anean scr ub at l as: A

compar at i ve anal ys i s . St r oudsbur g, Pa. :

Dowden, Hut chi nson & Ross; 1977. 237 p.

Wal t er, H. Vegetati on of t he ear t h i n rel at i on

t o cl i mate and t he ecophysi ol ogi cal

condi t i ons. ( Trans. f r om 2nd German ed. by

J oy Wi eser ) . New Yor k- Hei del ber g- Ber l i n:

Spr i nger- Verl ag; 1973. 237 p.Whi t t aker , R. H. Communi t i es and ecosyst ems. 2d

ed. New Yor k: MacMi l l an Co. ; 1975.

Van Der Zel , D. W. ; Kr uger , F. J . Resul t s of t he

mul t i pl e cat chment exper i ment s at t he

J anker shoek Resear ch St at i on, Sout h Af r i ca. 2.

I nf l uence of pr ot ect i on of f ynbos on str eam

di schar ge i n Langr i v i er . For . S. Af r i ca

16: 13- 18; 1975.

Zi nke, P. J . Mi nera l cyc l i ng i n f i re - t ype

ecosystems. I n: Mooney, H. A. ; Conr ad, C. E. ,

eds. Proceedi ngs of t he symposi um on t he

envi r onment al consequences of f i r e and f uel

management i n medi t er r anean ecosyst ems; 1977

August 1- 5; Pal o Al t o, Ca. : U. S. Dept . Agr i c. ,

For . Serv. and U. S. For . Serv. Gen. Tech. Rep.

WO- 3.

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