Interdependence of Groundwater, Riparian Vegetation, and Streambank Stability: A Case Study 1

Abstract

Groundwater is closely coupled with stream­ flow to maintain water supply to riparian vegetation, parti­ cularly where precipitation is seasonal. A case study is presented where Mediterranean climate and groundwater extraction are linked with the decline of riparian vegeta­ tion and subsequent severe bank erosion on the Carmel River in Carmel Valley, California.

Full text

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...
Interdependence
of
Groundwater,
Riparian
Vegetation,
and
Stream
bank
Stability: A
Case
Study
1
David
P.
Groeneveld
and
Thomas E.
Griepentrog
2
Abstract.
Groundwater
is
closely
coupled
with
stream-
flow
to
maintain
water
supply
to
riparian
vegetation,
parti-
cularly
where
precipitation
is
seasonal.
A
case
study
is
presented
where
Mediterranean
climate
and
groundwater
extraction
are
linked
with
the
decline
of
riparian
vegeta-
tion
and
subsequent
severe
bank
erosion
on
the
Carmel
River
in
Carmel
Valley,
California.
INTRODUCTION
By
their
nature,
riparian
systems
require
far
greater
amounts
of
water
than
other
terrestrial
ecosystems.
Groundwater
is
often
a
critical
source
of
supply
to
maintain
the
riparian
zone,
particularly
in
climatic
regions
with
seasonal
precipitation.
The
slow
drainage
by
aquifers
which
intersect
streamcourses
serves
to
maintain
channel
flow
during
dry
periods
and
to
support
the
plant
species
which
structure
the
productivity
and
character
of
the
riparian
ecosystem.
This
balance
may
be
particularly
sensitive
to
alteration.
Re-
moval
of
water
from
the
system
below
a
certain
threshold
equates
to
reduced
productivity
since
water
stress
necessitates
s·tomatal
closure
and
loss
of
carbon
fixation.
This
is
especially
so
with
riparian
species
since
they
are
adapted
to
moist
habitats
and
are,
as
a
group,
relatively
intoler-
ant
to
drought
stress.
Repeated
or
prolonged
re-
moval
of
water
from
the
system,
especially
during
dry
periods
may
therefore
induce
severe
impact
to
riparian
vegetation.
Alluvial
valley
fill
is
generally
an
excellent
source
of
groundwater
to
supply
man's
needs
where
high
permeability,
storage
and
rapid
recharge
from
streambed
infiltration
exist.
This
is
true
of
the
Carmel
Valley
aquifer
which
is
tapped
for
supply
to
regional
development
and
the
Monterey
Peninsula
in
particular.
This
study
documents
the
link
between
the
groundwater
extraction
from
the
Carmel
Valley
aquifer
and
the
decline
of
riparian
vegetation
along
a two
mile
section
of
the
Carmel
River.
Subsequent
severe
bank
erosion
along
the
impacted
lPaper
presented
at
the
Symposium on
Riparian
Ecosystems
and
Their
Management,
Tucson,
Arizona,
April
16-18,
1985.
2David
P.
Groeneveld,
Plant
Ecologist
and
Consultant,
Bishop,
California.
Thomas E.
Griepentrog,
P.E.,
Geohydrologist
and
Consultant,
Montrose,
Colorado.
44
stretch
can
be
explained
by
loss
of
root
stabili_
zation.
Groundwater
development,
while
necessary
for
man's
activities,
should
be
sensitive
to
potential
impac
ts
and
be
planned
accordingly.
The
potential
for
degrading
riparian
areas
and
subsequent
erosion
is
widespread
in
western
North
America.
In
addi-
tion
to
the
Carmel
River,
groundwater
pumping
has
been
implicated
in
impacts
to
riparian
systems
along
the
Platte
River
drainage
in
Colorado3,
the
Arkansas
River
in
Kansas
and
Oklahoma4 ,
the
Owens
River
drainage
in
California
5
and
the
Gila
River
drainage
in
Arizona
(Judd,
et
al.
1971).
PHYSICAL
CHARACTERISTICS
The
Carmel
River
drains
an
area
of
255
square
miles
in
the
northern
Santa
Lucia
Mountains
of
California's
Coast
Range.
The
watershed
extends
from
a
divide
elevation
of
over
5,000
feet
to
sea
level
where
the
river
discharges
into
the
Pacific
Ocean
just
south
of
Monterey
Bay.
Physical
characteristics
distinguish
the
Car'
mel
River's
upper
and
lower
reaches.
The
upper
river
and
its
tributaries
flow
in
steep,
narrow,
"V"
shaped
canyons
cut
into
Pre-Tertiary
igneous
and
metamorphic
bedrock.
In
its
lower
15
miles,
the
Carmel
River
flows
through
an
alluvium-filled
basin
underlain
by
Miocene
marine
shales.
The
~lluvial
soils
of
the
Carmel
floodplain
are
typi-
cally
poorly
developed
and
coarse
textured.
3Glenn L.
Crouch.
1982.
Personal
conversa-
tion.
U.S.
Forest
Service,
Rocky Mountain
Forest
and
Range Exp.
Sta.,
Fort
Collins,
Colorado.
4Ll oyd E.
Stullken.
1984.
Personal
conver-
sation.
United
States
Geological
Survey,
Garden
City,
Kansas.
sGroeneveld,
D.P.
and
T.E.
Griepentrog.
.~
Integrating
environment
with
groundwater
ext~:C~~C!
ASCE
Preprint
82-026.
Paper
presented
at
t
Annual
Convention,
April
26-30
at
Las Vegas,
Nevada.
198
2

The
ba
sin
receive
s f.rom 14
to
40
inches.
of
an.n-
r
ecip
ita
tio
n m
os
t l y
In
.
the
Jan
u
ary-~prll
perlod.
p
inch
es
per
year
lS
the
approxlmate
r e-
ave
rage
. T
he
Ca
rmel
River
discharg
e
averages
der
100
c.
f.
s.
on
a
long-term
basis
but
mea-
u;lo
W
has
bee
n
as
hig
h
as
8,62
0
c.f.s.
in
1969
fl ow dur
in
g
late
summer
of
drier
years.
z
ero
DO
MI
NANT
VEGETATION
Low
wat
er
r e
tention
of
th
e
floodplain
restri
cts
plants
in
th
e
ri
p
arian
zon
e
to
xeri
c or p
hrea
t op
hyti
c h
abit
due
to
the
long
dry p
er
i o
d.
The
water
lovin
g
species
are
ained
by
sha
ll
ow
gro
undwa
ter
and
surface
water
fr
om
the
rec
harge
r e
ce
ived
during
wint
e r
and
pre
cip
itati
o
n.
Trees
domin
at
e
th
e
matu
re
riparia
n
forest
al
ong
Carmel Riv
er
.
Althou
gh
th
e
composition
of
the
fore
s t
varies
highly
with
l o
cation,
with-
t
he
more
pr
i s
ti
ne
s
tands
it
is
co
mp
os ed of
appro-
e
ly
60
pe
rc
e
nt
red
willow
(Salix
laevigata),
cott
o
nwo
od (Pop
ulus
trichocarpa),
30
percent
o
per
ce
nt
Ca
lif
o
rnia
sycamore
(Platanus
race-
and
white
alder
(Alnus
rh
om
bif
ol
ia)
combined.
Two
disti
nct
z
ones
of
riparian
vegetation
cover
h
ealth
ca
n
be
viewed
a
lo
ng
th
e
lowe
r
twelv
e
miles
Carm
el R
ive
r . The l o
wermost
four
miles
in-
from
the
ocea
n
is
o
ver
grown
with
ne
arly
con-
red
wil
l ow
cro
wn
s whe
re
encroachment
has
th
e
riparian
forest
to
a
strip
lin
i
ng
the
lin
ea
r
eight
miles
ups
t
ream
have
mar-
rip
ar
ian
co
ver
(Fi
g.
1) . The
bank
clumps
of
the
rema
ining
ripa
r
ian
tr
ee
spe-
is
spars
ely
veg
etat
ed
with
weedy pe
rennials,
gras
s
es
and
xeric
sh
rub
specie
s.
The
de-
iverbanks
he
re
s
how
conspicuous
erosion.
A
porti
on of
this
zon
e was
chosen
for
de-
study
of
vege
tation
histo
ry
.
,
N
I
S
CALE
IN
MILES
o
C
l·--The
l owe r Carme l
River
Region.
on
to
ur
i
nte
rvals
a
re
1
,000
f
eet.
Rip
a
rian
Forest
Ch
an
ges
Thr o u
gh
Ti
me
The two z
ones
of
r i
pari
an
cov
er
obs
erv
ed
dur
in
g
fi
eld
survey
is
strikingly
eviden
t on
re
ce
nt
(1 980)
air
pho
tographs.
By
co
ntrast,
an a
na
ly
s i s of
pr
e-
1960
air
photographs
indi
c
ated
that
t
he
ri
ve
r
sup-
ported
a
continuous
cover
of
riparian
f o
res
t . A
series
of
six
photograph
s
ets
of
suitable
quality
we
re
assembled
to
document
t
he
c
ha
nge
of
r
ipa
ria
n
vegetation
thr
ou
gh
tim
e ;
blac
k
an
d
wh
ite
Un
ited
State
s
Soil
Con
se
rvati
on
Servi
ce
(
1956,
1966 , 19
71
and
1974),
Unit
ed
States
Fo
re
st
Ser
v
ice
colo
r
(1978)
and
colo
r
infrared
o
btained
from
a
pr
iva
t e
source
(1980).
Plant
cover
obse
rved
on
the
air
phot og
raphs
wer
e
mapped
onto
a
ba
se
prepared
from
the
U.S.G
.S.
Se
a-
side
7.5
minut
e
quadran
g
le
enlar
g
ed
t o
1:6
,00
0.
A
zoom t
ra
nsfer
sco
pe
out
fit
t
ed
wi
th
op
tics
f or c
or
-
rect
in
g
dist
or
tio
n
enab
l
ed
keying
the
cov
ertypes
into
correct
position
and
s
ca
le
by
refer
rin
g
map
fea-
tures
to
the
ground
images
on
the
air
pho
tog
raphs.
Vegetation
mapping
ca
te
gor
ies
w
er
e
kep
t
sim
pl
e
to
accommodate
the
range
in
detail
observable
on
the
widely
differ
e
nt
scale,
co
nt
ras
t
an
d qua
lity
of
each
photo
set.
Three
c
ove
r
ty
pe
ca t
ego
ries
wer
e
keyed
to
layer
s
of
ve
ge
tation
grea
ter
and
less
than
t
en
fe
et
in
hei
g
ht,
and
un
veg
eta
ted
rive
r
alluvi
u
m.
Canopy
height
was
inferred
by c r
os
s-r
efe
r e
ncing
eave
he i g
ht
on one s
tory
ho
uses
adj
a
ce
nt
t o
the
fl
o
odplain
using
an
ei
g
ht
power
mirror
ste
reosc
ope
to
accentuate
three
dimension
al d
ep
t h
of
fiel
d .
The
streambed
was
differentiate
d
fr
om
t
he
annual
grass
meadow
cover
by
te
x
ture
and
ton
e on
the
bla
ck
and
white
film
and
by
col
or on t
he
col
or
inf
rare
d
and
color
phot
o
sets.
The
mature
r i
parian
trees
ar
e
all
talle
r
tha
n
ten
feet.
Theref
o
re,
with
in
th
e
floodplain
,
the
map
category
for
tree
co
ve
r a
cc
ur
ately
r
eprese
nts
the
riparian
forest.
Field
che
cking
eliminated
trees
that
were
plant
e d
and
ma
in
tai
ne
d
by
ma
n.
The
time
serie
s
of
maps
sh
ow
n
on
Fi
gu
re
2 do
cu
-
ments
the
thinning
of
th
e
rip
a
rian
fo
r
es
t
readily
observable
on
the
photog
raphs.
Loss
of
ri
p
arian
f
or
est
cover
o
ver
the
24
year
pe
r i od
is
vi s
ible
initially
in
t
he
upstream
s
ec
tion
t o
war
d t
he
righ
t
of
the
1966 map.
Gradually
the
fo
r e
st
c
ove
r
les-
sens
in
the
remaining
se
c
tions
of t
he
study
area
until,
by 1978 , t
he
riparian
forest
cover
is
dis-
continuous
wi
t h much
of
th
e
remainin
g
ve
ge
t
atio
n
surviving
at
some
distan
ce
from
th
e
channel
margins.
In
1980,
the
ri
pa
rian
co
v
er
is
re
duce
d
even
fu
r
ther
and
t
he
riv
er
chann
el
has
widene
d
dra
mati
cal
l
y,
particularly
in
the
d
ow
ns
t r
ea
m
sections.
Foll
o
win
g
further
analys
is
,
tr
ee
pa
th
og
e
ns,
fi
re
and
en
c
roa
ch
ment
by
ma
n we
re
r u
led
out
as
pos-
sible
cau
s
al
ag
ents
for
the
decline
of
th
e r
ipari
an
forest.
The
decr
ease
of
rip
arian
tre
es c
oinc
ides
with
the
g
radual
devel
opment
of
t
he
Mo
nt
e rey
Peni
n-
sula
and
the
wells
to
exp
o
rt
groundwa
t er
to
meet
the
increasing
d
emand.
The w
el
l f
ie
ld
ex
tr
ac
ts
water
from
the
river
alluv
i
um
wi
t
hin
the
zone
of
veg
etatio
n
impact
noted
both
in
t he
fiel
d
an
d on
the
ai
r
ph
o
to
-
graphs.
The op
er
a
ti
ng
we l
ls
in
th
e
vegetatio
n
study
area
are
indicated
on
Fig
ur
e 2
in
the
s
e-
quen
ce
of
development
and us
e.
45

Figure
2.--Time
series
maps
of
the
study
area
with
the
riparian
forest
indicated.
The
study
area
is
divided
into
4
sections
according
to
the
location
of
high
capacity
export
wells.
GROUNDWATER
HYDROLOGY
AND
PLANT
RESPONSES
A
water
budget
assessment
of
the
study
area
was made
for
the
study
area
which
included
quanti-
fying
gains
and
losses
to
the
system.
Recharge
to
the
study
area
comes
directly
from
precipitation
on
the
valley
floor,
runoff
from
the
bordering
valley
sides
and
tributaries,
deep
percolation
from
surface
irrigation
and
septic
systems,
agri-
culture
return
flow,
down-valley
groundwater
flow
through
the
alluvium
and
in
the
river
channel.
Disposition
occurs
via
evaporation
transoiration
consumptive
domestic
uses,
outflow'of
the"
Carmel'
River,
downgradient
drainage
through
the
alluvial
aquifer
and
from
pumping
for
export.
Based
upon
conservative
estimates,
the
water
budget
indicated
that
local
consumptive
use
as
an
annual
total
was
only
about
eight
percent
of
the
aquifer
capacity
and
was
spread
throughout
the
year.
By
contrast,
pumping
for
export
was
seen
to
demand a
large
proportion
of
the
aquifer
capacity.
The down
valley
groundwater
flow
and
infiltration
from
the
channel
flow,
when
available,
tend
to
re-
charge
the
basin
at
a
rate
slower
than
pump
extrac-
tions.
This
recharge
somewhat
buffers
the
draw-
down
in
the
system
so
the
drawdown f
rOm
p
d
ten
s
to
be
greatest
during
late
s
umpinD
f
..
ummer
ad"
-
Th
e
~ve
foot
~socontour
of
groundwater
d n
fall.
from
the
spring
high
levels
to
an
0
raWd~
"
ctober
1
1
potted
on
F~gure
3.
These
zones
of"
ow
afe
" 1
mf~
c~rc
e
the
export
wells
and
corres
d enee
~,;
pon
well
..
~
the
zones
of
riparian
vegetation
d 1"
With
2 -
ec
1ne
on
Fi
.
gure
Figure
3.
--Zones
of
inf
luence
in
October
for
four
select
years.
The 5
foot
isocontour
of
draw-
down
from
the
spring
high
is
the
zone
boun-
dary.
The
limits
of
the
valley
fill
are
indicated.
Riparian
Water
Requirements
Young
and
Blaney
(1942)
measured
water
con-
sumption
by
willow
in
Santa
Ana,
California
to
be
about
56
inches
during
the
period
from June
through
September.
It
is
reasonable
to
assume
that
willow
and
other
riparian
vegetation
within
the
slightly
more humid
Carmel
Valley
would
transpire
at
least
30
inches
per
year
through
the
same
period.
The
average
June
throu~h
September
precipitation
is
less
than
one
inch
confirming
that
willowS
and
other
riparian
vegetation
are
groundwater
depen-
dent.
6
Catlll
el
United
States
Weather
Bureau
Records.
Valley,
California.

Tree Root s and
Declinin
g W
ater
Tabl
es
75
-
An
imp
li
ed
question
is
posed
by
the
hy
d
rol
o-
l
ys
i s :
ca
n
the
roots
of
riparian
phrea
t
o-
ana .
bl
?
fo
ll
oW
a
retreatlng
water
ta
e . To
answer
ti
o
n,
so
il
pits
were
du
g a
ro
und
the
base
wil
lo
w
(
~.
la
ev
i g
ata
)
in
the
study
area
lat
e summer. The
ro
o
ts
of
the
r ed
willow
on
ly
to
a
dept
h d
elimi
ti
ng
th
e be d
ele-
of
the
adja
c
ent
dry
chann
el
.
Thes
e
roots
quit
e
fra
g
il
e
and
spo
n
gy
due
to
the
presence
cortic
al
ai
r
sp
ace
s.
cortical
air
spaces
c
al
le
d
ae
renchyma,
are
stic
of
many
wetl
an
d
species.
The
air
ar
ise
by
lysis
wi
t
hin
parenchymal
tissue
have
been
f
ound
to
improve
oxygenation
to
root
(Coutts
and
Armstrong,
1978),
(Kawase
and
,19
80) .
This
morphologic
adaptati
o
n,
,
probabl
y
reduc
e s
the
penetrating
power
root
tips
because
the
induced
sponginess
both
the
axial
ri
g
idi
ty
and
radial
anch
o-
cited
by
Barley
and
Greacen
(1967)
as
nec
e
s-
for
efficient
soil
penetration
by
roots.
Black
cottonwood
roots
in
the
vicinity
of
the
t e
st
pits
were
undercut
and
washed
free
the
bank.
Th
e
se
roots
showed
the
same p a
t-
of
truncati
on
at
about
the
elevation
of
the
t
channel
noted
for
the
red
willow.
The
reason
that
th
e
observed
willow
and
co
t -
root
systems
had
not
adapted
t o
follo
w
water
t a
ble
retreat
may
be
due
to
soils
flo
o
dplai
n . The f
loodplain
subs
t
rate
is
c
oarse
and
retain
s
only
small
amounts
of
w
at
er
draina
ge
.
Thrs
restrict
s
contact
of
matri
x
films
aft
er
complete
dr
ain
ag
e
fr
om
pumping.
necessary
for
inducing
deep
er
rooting
fore
probably
broken
during
r
apid
wa
ter
line.
Poplars,
of
wh
ich
t
he
bl
ack c o
t-
a member,
have
bee
n
observed
by
Hoff-
,
as
cited
by
Kr am
er
and K
ozl
ow
ski,
1979)
fi
ve
centim
e
ters
per
day
growth
rates.
rates
are,
of
course,
moderated
by
soil
im-
and
the
timing
r
equired
for
redifferen-
root
buds
f r
om
ae
re
nchyma
tous
tissue
to
m
ore
suited
for
exploring
the
soil
.
Sequence
of
Events
Each
of
the
cov
er
type
maps shown
in
Fig
. 2
fitted
with
a
cl
ea
r
template
delimiting
a
ri-
corr
i
dor
al
on
g
the
river.
The
study
area
divided
int
o sec
ti
ons
conforming
to
the
loca-
of
high
capa
ci
ty
wells
designated
fr
om down
; Sc
hul
te,
M
anor,
Berwick
and
Begonia.
pl
animet er was
used
to
obtain
three
re
plica-
of
the
area
of
the
riparian
forest
an
d
unve-
ed
river
al
luvium
co
ver
types.
.
These
values
averaged
to
yiel
d da
ta
document i
ng
t he
tern-
rel
a
tionship
of
ripari
an ve
ge
tat
ion
de
cline,
chann
el
erosion
and
pumping
7
plotted
on
4.
Pump
pr
oduc
ti
on r
ec
ords
obtained
from
t
he
ornia-Am .
erl
c
an
Wa
ter
Company .
SCHUL
TE
75
-
:;0 -
1000
.--
•
MA
NOR
:-----:
:>
':i
,dJ
,"oc
19
60
1970
1980
BEGON
IA
7 5 -
5
0-
2
5-
.
--
I
It
1.)
..
•
•••
.....
.
....
::.
i.
e-e
-1000
-5
00
e «<
1950
198
BERWICK
F
igure
4.--
P
erc
e
nt
cover
by
ri
p
ari
an
f
or
e
st
(diamon
d
s)
and
un
veg
etate
d
river
ch2nn
e l
(c
i
rcles)
ver
sus
pumpi ng i n ac
re
feet
f r om
wells
in
eac
h se ct
ion.
P
UMPING,
VEGETATION
DE
CLINE A
ND
CHANNE
L
ER
O
SION
Kondolf
(198
3)
ana
lyzed
the
geomorph
olog
y
of
t
he
C
ar
mel
River
system
to
det
ermi
ne
the
c
ause
and
ef
fe
ct
relationship
for
the
m
ass
i ve
streamb
a
nk
ero
si
on
by
measuring
su
ch
par
a
meters
a s
ri
ver
sinuosity,
bed
load,
gr
ad
ient
and
ch
ann
el
co
n
figur-
at"ion
in
relation
to
influencin
g
fact
or
s s
uch
as
historic
fires
in
the
catchm
e
nt
basin,
streamb
ed
minim
g ,
constructio
n of dams
upstr
e
am
and
the
timing
and
rate
of
ri
ver
f l
ows.
Kond
olf
c
onc
lude
d
that
although
j'some
ba
nk e
ro
s i on i s n
atur
al
in
most
fluvial
systems
'"
nat
u
ral,
random
p
roces
s
i s
inadequate
to
ex
p
lain
t he ma
ss
iv
e
ba
nk
er o
si
on
experienced
along
the
Carm
el
Rive
r
in
1978 . Th
is
erosion
must
be
r e
garded
as
out
of
the
ord
in
ar
y
in
t h
at
it
occurred
d
uring
ye
ars
unremark
a
ble
for
high
flows."
A
fter
le
ng
thy
e
xa
min
atio
n
of
t
he
ph
y-
sical
sys
tem,
Kondolf
conc
lude
d
that
the
bank
ero-
sion
was
coupled
with
groun
dwater
pum
pi
ng
through
dieoff
of
riparian
v
egetati
on .
Streamb
a
nk
stab
ili
zation
by
veget
a t i on
resul
ts
fr
om
the
reinforcing
n
atu
r e
of
t
he
plan
t r
oots
.
T
his
mechanism
is
docu
mented
in
the
lit
er
a
ture
an
d
though
limited
discus
sion
wil
l
be
ma
de
h
ere,
the
re
ader
is
urged
to
se e
Sm
ith
(1976 ) ,
Sei
be
r t
(1
968
),
Z
iemer
(1981)
a
nd
Gray
an d
Leise
r
(1
982) f
or
more
ba
ckground.
In
summary ,
streambank
s t
abiliz
at i on
by
ro
ot
s
results
from i
nc
r e
ase
d t
ens
i
le
and
sh
ear
47
7

strength
of
the
bank
soil
mass
and
through
armor-
ing
provided
by
roots
as
they
wash
free
from
the
substrate.
These
mechanisms
were
obviously
lack-
ing
for
the
readily
erodable
bank
material
within
the
impact
area.
The
most
severe
erosion
of
streambanks
on
the
Carmel
River
occurred
within
the
study
area.
A
time
series
of
photographs
taken
from
the
Schulte
Road
Bridge
looking
upstream
document
the
process
of
bank
erosion
following
loss
of
stabilizing
plant
growth
(Figures
5,
6
and
7).
The
photo
point
can
be
located
on
the
maps
of
Figure
2
as
the
double
line
between
the
Schulte
and
Manor
sec-
tions
of
the
river.
The 1976
photograph
was
taken
in
late
fall
1976
and
shows
dead
cottonwoods
and
willows
lining
the
approximately
60
foot
wide
channel.
The 1978
photograph
captures
the
same
scene
following
spring
high
water
flows
which
equate
to
a
ten
year
recurrence
interval
(Kondolf,
1983).
Note
that
the
toe
of
the
bank
has
been
eroded
back
about
30
feet
from
the
channel
margin
position
visible
in
1976.
According
to
photogram-
metry
of
the
1978
air
photograph
set,
the
erosion
due
to
this
flow
resulted
in
an
ultimate
channel
width
of
about
150
feet
within
the
field
of
view
of
the
photograph.
A
photograph
following
spring
high
water
flows
in
1982
illustrates
the
same
scene
but
with
aggradation
of
the
margins
to
form
a
channel
over
400
feet
wide.
This
erosion
occurred
following
two
five
year
recurrence
inter-
val
flows
in
the
intervening
four
year
period.
SEd
Lee.
1982.
Photographs
of
the
Carmel
River.
Board
of
Directors,
Monterey
Peninsula
Water
Management
District.
Figures
5,.6
and
7.--1976
8 , 1978 6 and
1982
graphs
of
the
Carmel
River
Channel.
thhoto~
arrow
indicates
a
reference
point.
e
LITERATURE
CITED
Barley,
K.P.,
and
E.L.
Greacen.
1967.
Mech
i .
. .
~~
reSl.stance
as
a sOl.l
factor
influencing
the
growth
of
roots
and
underground
shoots.
Advances
in
Agronomy,
19:1-43.
Coutts,
M.
P.
and
W.
Armstrong.
1978.
Role
of
oxygen
transport
in
the
tolerance
of
trees
to
waterlogging.
In
M. C.
R.
Cannell
and
F.
T.
Last
(eds.)
Tree
physiology
and
yield
improvement.
Academic
Press,
New
York.
Gray,
D.H. and A.
Leiser.
1982.
Biotechnica1
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protection
and
erosion
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v~
Nostrand
Reinhold,
N.Y. 271
pp.
Judd,
B.
Ira,
James
M.
Laughlin,
Herbert
R.
Guenther
and
Royal
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1971.
The
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of
mesquite
on
the
Casa
Granl
National
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Great
Basin
Naturalist.
31:153-159.
Kawase,
Makoto
and
Robert
E. Whitmoyer.
1980.
Aerenchyma
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in
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J.
Bot.
67:18-22.
KondoH,
C .M.
1982.
Recent
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historic
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University
of
California
at
Santa
Cruz.
112
pp.
Kramer,
P.J.,
and
ToT.
Kozlowski.
1979.
PhysiC
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of
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Academic
Press,
New
York,
N.Y. 809
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P.
1968.
Importance
of
natural
veget;
tion
for
the
protection
of
the
banks of
streams,
rivers
and
canals.
In
Fresh~ater
Studies,
Nature
and
Environmental
Senes.
Council
of
Europe,
Strassbourg.
3:
35-64.
Smith,
D.C.
1976.
Effect
of
vegetation
on
anastamosed
channels
of
a
glacier
meltwate
.
river.
GSA
Bull.
87:
857-800.
Young,
Arthur
A.
and
Blaney,
Harry
F.
1942.
Use
of
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by
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vegetation.
Calif.
D~p.
Public
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Water
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50:
150
pp.
Ziemer,
R.R.
19~1.
Roots
and
stability
of
forested
slopes.
In
Erosion
and
sedime~
transport
in
Pacific
Rim
steeplands.
I
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No.
132:
343-361.
48