Conservative Lithium in Tamar Estuary

7/23/2019 Conservative Lithium in Tamar Estuary

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Estuarlne Coastal and Shelf Sdence

0 9 8 2 ) x 4 , 5 7 7 - 5 8 7

C o n s e r v a t iv e e h a v i o u r o f D i s s o l v e d

L i t h i u m in E s tu a r in e W a t e r s

P a t r i c i a S t o f f y n E g l i ~

Department of Oceanography Dalhousie University

Halifax Nova Scotia B3H 4Jx Canada

]~eceived 2o February I98I and in revised orm 28July 198I

K e y w o r d s l i th i u m ; g eo ch em i s t ry ; e st u a ri e s ; m i x i n g ; S a i n t L aw r en ce

es t u a r y ; N e t h e r l an d s co as t

T h e co n cen t r a t i o n an d d i s t r i b u t io n o f d is s o lv ed l i th i u m h as b een d e t e r -

m i n ed i n t h e S t . L aw r en ce R i v e r an d t h e S ch e l d t R i v e r e st u ar ie s . D i ss o l v ed

L i b eh av es co n s e r v a t iv e l y i n b o t h e s tu a r ie s d u r i n g m i x i n g o f r i v e r w a t e r

w i th s eawater . I towever , a loca l i zed input o f d i s so lved L i ex i s t s in the

Scheld t es tuary , which i s be l i eved to he caused by indus t r i a l d i s charge .

I n t r o d u c t i o n

T h e f a t e o f ri v e r - b o r n e a l k a li an d a l k al in e ea r t h e l em en t s i n t h e o cean s i s st il l an o b j ec t o f

d eb a t e . I t h a s b een s u g g es t ed , o n t h e b as is o f ex p e r i m e n t a l ev id en ce , t h a t t h e g l o b a l r i v e r

i n p u t f l u x o f d i s so l v ed N a , K , C a an d M g co u l d b e s i g n i fi c an tl y m o d i f i ed w i t h i n e s t u a r i e s

b y c a t i o n ex ch an g e r eac t i o n s w i t h s u s p en d ed c l ay m i n e r a l s ( R u s s e ll , I 9 7 o ; S ay l e s

M a n g e l s d o r f , x 9 77 ). O w i n g t o t h e l a ck o f i n f o r m a t i o n o n t h e b eh a v i o u r o f tr a cc a lk a li an d

a l k a l i n e ea r t h c a t i o n s d u r i n g e s t u a r i n e m i x i n g , t h e s e e l em en t s a r e o f t en a s s u m ed t o b eh av e

c o n s e r v a ti v e ly i n e s tu a r ie s . H o w e v e r , H a n o r C h a n ( , 9 7 7 ) h a v e d o c u m e n t e d t h e n o n -

co n s e r v a t i v e b eh av i o u r o f d i s so l v ed B a i n t h e M i s si s si p p i R i v e r e s t u a r y w h e r e B a ap p ea r s t o

b e r e l e a s ed i n t o s o l u t i o n o w i n g t o d e s o r p t i o n f r o m c l ay m i n e r a l s .

I n a r e c e n t s t u d y o f th e m a s s b a l an c e o f d is s o lv e d l it h i u m i n t h e o c e a n s b y t h e a u t h o r

( E g li , x 9 7 9), i t w as n ece s s a r y t o k n o w w h e t h e r t h i s e l em en t b eh av e s co n s e r v a t i v e l y o r n o t

d u r i n g e s t u a r i n e m i x i n g . F o r t h i s p u r p o s e , t h e co n cen t r a t i o n an d d i s t r i b u t i o n o f d is s o lv ed

L i i n t i le S t . L a w r en ce R i v e r e s t u a r y (C an ad a ) an d t h e S ch e l d t R i v e r e s t u a r y ( B e l g i u m an d

N e t h e r l an d s ) h av e b een i n v es t i g a t ed . T h i s p a p e r r ep o r t s t h e r e s u l t s o f t h i s i n v es t ig a t i o n

w h i ch i n d i ca t e t h a t d i s so l v ed L i b eh av es e s s en ti a l ly a s a co n s e r v a t i v e e l em en t i n e s t u a ri e s .

S a m p l i n g a n d a n a ly t ic a l m e t h o d s

V er t i ca l w a t e r co l u m n s am p l e s w e r e co l l e c t ed a t 2 6 s t a t io n s d i s t r i b u t e d o v e r th e en t i r e

l e n g t h o f t h e S t . L a w r e n c e e s t u a r y ( 3 5o k m f r o m Q u e b e c C i t y to P o i n t e d e s M o n t s , s e e

F i g u r e x ) an d i n t h e G u l f o f S t . L a w r en ce ( s a li n i ty r an g e o f o 'o 4 -3 5~ o o ) . T h e s am p l e s w e r e

im m edia te ly f i lt e r ed on o .8-/~m po re s i ze s i lver f i l te r s and , a t s ev era l s ta t ions , an o th er

~ address: Atlantic Geoscience Center, Geological Survey of Canada,

Department of Energy, Mines and Resources, Bedford Institute of Oceanography,

Dartmouth, Nova Scotia, B2Y 4A 2, Canada.

5 7 7



578

P. Stoffyn Egli

7 3 e 7 2 = 7 1 9 7 0 9 6 9 ' ~ 6 8 ~ e 7 = 6 5 = 6 5 0 6 4 o 6 3 ~ e 2 Q 6 10 6 0 ~ E ~ o 5 8 = 5 7 = 5 6 0 5 5 9 5 4 = 5 3 0

2 ~ . [ . . 5 2 g

4 ~ , [ . .~ f l . c

. .I ..

. 4 5 , . : ~ . ~ : ' t , ~ . . . . . 45

. ]. [ . [ ~

O C E A N

4 3 o

. ':: :~ q k i . . . . . . . . . . . . . .

4 2 0

7 3 1 7 2 0 7 1 0 7 0 = ( 3 go 6 8 0 ( 3 7 r e 6 o ( ~ 51 6 4 = E ;3 o 6 2 = 6 1 1 ~ 0 1 5 g 9 5 8 0 5 7 0 5 6 0 5 5 = 5 4 0 5 3 =

Figu re x. l~lap of the S t. L awrence River estuary.

a l iquo t was f i l t e r ed on o .4-1am por e s i ze Nuc lepo re po lyca rbon ate f il te rs9 B ecau s e t h e

S ch e l d t e s t u a r y i s a r e l a ti v e l y w e l l m i x ed e s t u a r y ( v e r t ic a l s a l in i t y v a r ia t io n s s e l d o m ex ceed

x~oo, P e t e r s & S t e r l i n g , z9 7 6 ), o n l y s u r f ace w a t e r s am p l e s w e r e co l l e c ted d u r i n g t w o s u r v ey s

z m o n t h a p a r t b e t w e e n B r e s k e ns a n d D e n d e r m o n d e ( s e e F i g u r e 2 ; s a li n it y r a n g e o f o .5 8 -

a7~oo . Th e sam ples w ere f i l t e r ed the s ame da y on M i l l ipore ce l lu lose ace ta te f il t e r s, one

a l iqu ot on o-45-11m po re s i ze f i lt e r s , an o th er a l iquo t on o .os - l am po re s i ze f il t e r s . T h e

f i l te r ed s am p l e s w e r e s t o r ed a t 4 ~ i n 3 ~ m l p o l y e t h y l en e o r p o l y p r o p y l en e b o t t l e s u n t i l

an a l y si s . T e s t s s h o w ed t h a t t h e t y p e o f f i lt e r (s i lv e r , p o l y ca r b o n a t e o r c e l l u lo s e ace t a te )

u s ed o r t h e s t o r ag e t i m e ( x w eek t o 5 m o n t h s ) d o n o t a f f ec t t h e L i co n cen t r a t i o n o f t h e

s am p l e s . M o r eo v e r , t h e r e w as n o s i g n i fi c an t d i f f e ren ce i n L i c o n cen t r a t i o n b e t w een a l i q u o ts

of a g iven sam ple f i l t e r ed on d i f f e ren t po re s i ze f i lt e r s .

S a l in i ty w as m e a s u r e d w i t h a n in d u c t i o n s a l in o m e t e r ( + o . o x % ) i n t h e S t . L a w r e n c e

e s t u a ry s a m p l e s a n d w i t h a w i d e r a n g e c o n d u c t i v i m e t e r ( - b x % ) i n t h e S c h e d l t e s t u a r y

s am p l e s . D i s s o l v ed L i w as m eas u r ed b y f l am e em i s s i o n s p ec t r o s co p y . S am p l e s h av i n g a

s a l i n it y o v e r x o ~o o w e r e d i l u t ed t o k eep t h e s a l in i t y o f t h e s o l u t io n s i n j ec t ed i n t h e f l am e

below zoyoo ,w h i c h r e su l ts i n m o r e r e p r o d u c i b l e m e a s u r e m e n t s . F o r e a c h b a t c h o f sa m p l e s

a n a ly s e d , a m i x t u r e o f eq u a l v o l u m e s o f e ac h s a m p l e w as p r e p a r e d . K n o w n a m o u n t s o f L i

w e r e ad d ed t o e ach o f f i v e a l iq u o t s o f th i s m i x t u r e d i l u t ed l i k e t h e s am p l e s . T h es e s o l u t io n s

w er e u s ed t o c a l i b r a te th e i n s t r u m en t . S t an d a r d s o l u t io n s p r ep a r ed i n t h i s w ay h av e ch em i ca l

an d p h y s i ca l p r o p e r t i e s si m i l a r t o t h o s e o f t h e s am p l e s an d t h e s a l i n i ty d i f f e r en ce b e t w e en

s t an d a r d s o l u t io n s an d s am p l e s n ev e r ex ceed ed 3 ~oo . T h e em i s s i o n i n t en s i t y o f t h e s t an d a r d

s o l u t i o n s an d t h e s am p l e s , d i lu t ed a s r eq u i r ed , w as m eas u r ed a t a w av e l en g t h o f 6 7 o .8 n m

w i t h a P e r k i n E l m e r a t o m i c a b s o r p t io n s p e c t r o p h o t o m e t e r (a i r -a c e t y le n e fl am e ) . T h e

e m i s s i o n b a c k g r o u n d c a u s e d b y s e a s a l t s o t h e r t h a n L i w a s m e a s u r e d u n d e r t h e s a m e



D i s s o l v e d l i t h h t m i n e s t u a r i n e w a t e r s

579

Figure z. Map of the Scheldt River estuary.

co n d i t i o n s a t 6 7 0 4 an d 6 7 I ' z n m , w h e re n o L i em i s s io n is o b se rv ed w i t h t h e s l it u sed

(o. 4 n m sp ec t ra l b an d w i d t h ) . T h e av e rag e b ack g ro u n d fo r e ach sam p l e i s su b t rac t ed f ro m

i t s emiss ion s igna l recorded a t 67o .8 nm . T he s lope of t he ca l ibra t ion li ne (emiss ion in t ens i ty

v s . L i ad d ed ) i s u sed t o c a l cu l a te th e L i co n cen t r a t io n o f th e s am p l e s . T h e p reci s io n o f t h e

resu l t s i s -4-x ~o and the accura cy 4 -5% .

e s u l t s a n d d i s c u s si o n

T h e L i an d sa l i n it y d a t a a r e l is t ed i n T ab l e r an d t h e L i co n cen t r a t i o n i s p l o t t ed v s .

sa l in i t y i n F i g u re 3 fo r t h e S t . L aw ren ce e s tu a ry an d i n F i g u re

4 a )

an d (b ) fo r t h e S ch e l d t

e s t u a ry d u r i n g t h e M ay an d Ju n e I9 7 7 su rv ey s , r e sp ec t i v e l y . T h e f i g u re s a l so sh o w t h e

theore t i ca l d i lu t ion l ine wh ich i s t he l i ne wh ere the ana ly t i ca l po in t s sho uld p lo t i n a L i v s .

sa l in i t y d i ag ram i f th e d i s so lv ed L i d i s t r i b u t io n i n t h e e s t u a ry r e su l t s o n l y f ro m p h y s i ca l

m i x i n g o f r i v e r w a t e r an d seaw a t er ( co n se rv a t iv e b eh av i o u r ). T h e d i l u t io n l in e i s d e f i n ed

b y t h e L i a n d s a lt c o n t e n t o f t h e t w o p u r e e n d - m e m b e r s , r i v er w a t e r a n d s e aw a te r . T h e

seawater com posi t ion used to def ine the d i lu t ion l i ne is t he average L i : CI ra t io of sea-

wa ter (9 35 Pg L i g-X C I or x8 i lag L i 1 t a t 35~oo sa l in i ty ) ca l cu la t ed f rom publ i shed da ta

(C h o w & G o l d b e rg , 1 9 6 z ; R i l ey & T o n g u d a i , I 9 6 4 ; F ab r i can d

e t a L

x966; Angino &

B i ll in g s , i 9 6 6 ; M o ro zo v , I9 6 8 ; E g l i, i 9 7 9 ). T h e f r e sh w a t e r en d -m em b er co m p o s i ti o n u sed

i n t h e ca se o f t h e S t . L a w ren c e R i v e r i s t h e av e rag e co m p o s i ti o n o f s am p l e s h av i n g a s a l i n it y

belo w o 'o6~oo (z lag L i 1 x, o.O5~oo sal ini ty) . Fo r the Sch eldt Riv er w ater, the com posi t ion o f

the f i r s t wa ter sam ple co l l ec ted dow nst ream of the t r ibu tar i es (a t ScheUe, 9 z km ups t ream

f ro m B resk en s ; x9 lag 1-1, o '7~oo sal ini ty) was cho sen to define th e di lu t ion l ine in ord er to

avoid a r t ifac t s due to t r ib u tar y d i scharge .

F i g u re 3 sh o w s t h a t d i s so lv ed L i i s co n se rv a t iv e i n t h e S t . L aw ren ce e s t u a ry ; t h e d a t a

poin t s a l l p lo t c lose to the d i lu t ion l i ne , wi th in the l imi t s o f ana ly t ica l e r ror , an d the

regress ion l i ne th rough the da ta po in t s p rac t i ca l ly co inc ides wi th the d i lu t ion l i ne . In the

ca se o f th e S ch e l d t e s t u a ry m o s t d a t a p o i n t s a l so p lo t o n a s t r a i g h t l i n e , b u t t h i s l i n e d o es



5 8 0 P. Stoffyn-EgH

T m 3 L e 1. S a l i n it y a n d d i s s o lv e d L i d a t a i n t h e S t . L a w r e n c e a n d S e h e l d t e s t u a ri e s .

P r e c i s i o n : s a l in i t y , + o . o i % (- 4- I ~ 0 i n t h e S c h e l d t e s t u a r y ) ; d i s s o l v ed L i , 4 - 1 %

S t . L a w r e n c e e s t u a r y

S a m p l i n g d e p t h S a l i n it y D i s so l v ed L i

D a te (po s i t ion ) (m) (~oo) ( lag l - t )

2 6 A u g u s t 1 9 7 9

( 4 8 ~ 6 z ~

2 7 A u g u s t x 9 7 9

( 4 9 o 9 o ' N , 6 4 ~

2 8 A u g u s t x 9 7 9

( 4 9 * 1 5 o ' N , 6 6 0 2 9 o ' W )

( 4 9 ~

6 7 ~ x . 3 W )

( 4 8 ~ 6 8 ~

2 9 A u g u s t 1 9 7 9

( 4 7 ~ 6 9 ~

( 4 7 2 8 ' o ' N , 7 o ~

( 4 7 ~ 7 o ' 2 9 o ' W )

x 30 972 163

2 0 3 1 o o 5 I 6 3

2o 31 281 165

3o 31 791 168

50 32 316 171

I o o 3 3 I o o 1 7 4

I 5 0 3 3 I 2 3 1 7 4

2oo 34 539 179

2 5 o 3 4 6 8 6 I 8 a

3 0 0

34 772

* 7 9

350 34 845 *82

400 34 863

x 8 z

29 I58 155

XO 27 668 146

20 29 299 149

3 0 2 9 8 4 7 I 5 5

4 0 3 v 7 2 7 I 6 8

50 32 037 169

xoo 33 202 174

xS

3 3 6 9 z I 7 5

2 o o 3 4 2 t 8 x 7 7

25 ~ 34 440 I81

300 34 689 18z

x 27 905 x43

I o 2 8 . 8 8 8 1 4 7

a o 2 9 8 2 8 I 5 3

3 ~ 3 0 8 7 4 I 6 i

4 ~ 3 I 574 165

5 ~ 3 I 996 x69

x

2 6 o x 5 I 3 6

lO 29 55a 15 I

2 o 3 0 5 6 3 I 5 8

3 ~ 3 I '2O3 x63

4 ~

32 I35

169

5 o 31 49 t 169

I 26 414 136

I 0 2 8 ' 9 0 9 1 4 9

2 0 3 o ' 2 9 1 I 5 8

3 ~ 3 I 'O55 163

4 ~ 3 I 8 4 2 I 6 8

50 32 223 x69

t o o 3 2 7 o 7 I 7 1

x s o

33 721 174

200 34 156 175

250 34 186 175

300 34 303 177

325 34 4o5 xSz

x I 9 . 5 5 6 x o4

xo 20 672 xo9

I 18 7x6 1oo

io 19 561 xo5

x 7 579 43

5 z o ' 5 3 4 5 4

xx

1 2 6 6 t 6 4



Dissolved lithium in estuarbte waters 5 8

TABLE x.- -co nt.

30 August I979

(47~ 7o~ 1 x x.oo6 59

5 20 290 to7

i

5

20 708 r xo

(47~ 7o~ x x 1 926 63

5 14 749 73

25 23 486 124

(47~ 7o~ t I I'817 61

5 1 6 9 1 o 9 1

IS 23 720 122

(47~ 7o~ i 6 3 ~ 34 4

5 x2 409 64

(47~ 7o029.o'W) 1 7 786 42

1o 8 397 44

15 11 o54 59

(47 ~ o'N, 7o~ o'W) 5 5 206 25 6

1 5 9 2 5 ~ 4 9

(47~ o. o'N, 7o038.o'W) 1 3 857 2z'5

5 6 832 35 7

x5 I5 629 78

(47~ 7o~ 1 6 592 34 0

5 Io 929 59

1 5

13 399 66

(47~ 7o~ x 6 23I 33 1

5 6.882 35 9

t 5 13 o64 70

(47~ 7o~ 1 3 970 22 4

5 5 r26 27 8

15

t o ' 6 o 5

56

(4 7~ 7o~ x 2 8ot x7 4

5 3 179 18 5

15 7 521 37 4

(46~ 7o~ 1 0 056 2 o

5 0 058 2 3

3t August 1979

(46~ 710o3.5'W) x 0 049 2.0

io 0.050 2.0

2o 0 057 1.9

(46~ 7x ~ x 0.056 2 o

5 0 048 x.9

2 0 0 047 2 1

(46~ 7z ~ x 0 042 2 0

x

o

0 043 2 o

20 0 044 2 0

(46~ 7o~ x 0 044 2 0

5

0 045 2.o

x

2 0.046 2.0

(47~ 7o~ 1 0 337 3 7

5 0'903 6 7

xo 0 942 6.8

(47~ 7o~ x 5 289 28 4

8 12 o77 66

(47~ 2.o'N, 7o036 5'W) x 5 486 29 3

5 5 504 29 5

12 lO'566 56

(47~

7 o ~

1 4 726 25 8

x o

5 488 29 5

2o I4 77 ~ 74

x September I979

(47~ 7o~ z.o'~V) x 8 860 49

5 zo'157 54

x5 26 76z 83



5 8 2

P. Stof fyn Egl i

T A BL E l . - - c o n t .

(47~ 7o~ l 13 742 72

1o 26 783 138

2o 27 156 143

( 4 7 ~ 7 o ~ t t 8 o 1 7 9 7

t o

23 072

2 o

25 26 426 133

5 o 28 '6 39 753

(47~ 7o~ 1 22 669 ~19

I o 2 2 9 3 7

2 o

25 25 x96 129

50 28 oo5 146

( 4 7 ~

6 9 ~

t 18 829 zo3

~o 22 654 ix9

2 o

28 276 145

30 29 251 15o

4 ~ 2o 'o87 158

50 30 466 158

t o o 3 0 8 5 3 x 6 t

13o 3o '84 3 I61

( 4 7 ~ 6 9 ~ t 2 0 - 6 9 8 1 i t

i o

23 367 122

25 28 409 I47

5 o 3 0 ' 6 5 7 1 63

65 3 I 485 165

( 4 8 ~ 6 9 ~ I 2 2 0 6 7 t t 7

xo 23 895 124

25 28 125 144

45 30 -396 ]61

(48~ 69~ x 23 881 124

t o 2 9 q 8 1 I 4 9

25 31 o99 i61

S c h e l d t e s t u a r y

L o c a t i o n o f s a m p l e s S a l i n i t y D i s s o lv e d L i

D a t e 0 i m u p s t r e a m o f B r e s k e n s ) (% 0) ( p g 1 - t )

3 M a y I 9 7 7 6 8 5 2 o 3 2 7 ' o

71 5 1-47 24 9

73 5 l -2 t 23 4

76 5 o '9 o 19 4

79 o '84 29 5

81 o .81 19 5

8 3 o ' 7 5 x9 o

8 5 o ' 7 2 1 9 ' 2

87 5 o '71 19 -z

89 5 o 7o 2o - t

92 0 '65 19 6

94 o '63 18 .8

97 5 o .6 z 18- 7

zoo '5 o -61 20 '0

I o 3 5 o ' 6 o 2 o . 6

Io8 5 o '6 4 20 7

t z 5 0 64 22 4

I t 9 o ' 6 5 2 3 3

I21 5 0 60 16 2

4 M a y I 9 7 7 3 9 t 3 6 9 1

43 13 6 86

46 5 13 2 85

51 1o 3 69



Dissolved lit hium in estuarine u aters

583

TABLE I.~COnt.

54 5 9 3

57 5 7 9

59 5 7 .6

61 5 5 9

64 5 5 o

66 5 3 89

68 5 3 21

7I '5 2 22

5 May x977 2 25 4

9 24 9

x4 24 0

20 21 3

25 20 5

3 t 5 x9 3

35 17 I

39 15 7

7 June I977 68 5 4 94

7I 5 3 80

73 5 2 85

76 5 1 95

79 1.68

8t 1 51

83 x'27

85 x'13

87 5 0.86

89 5 0'83

92 o'77

94 0 76

97 5 0 68

Ioo'5 0.60

1o3 5 0 59

Io8 5 0-58

115 0 59

119 0'62

8 June I977 35 18 o

39

43 w

46 5 14 6

51 12 2

54 5 xx.o

57 5 9 7

59 5 9 3

6I 5 7 4

64 5 6 7

66 5 5 3

68 5 4 54

7z'5 3 29

9 Ju ne 1977 2 27 0

9 26 4

14 24 9

20 23 4

25 22 6

3I 5 2I' 6

35 19 4

39 16-2

11 Febr uary 1978 6* 28 2

14* 29 8

24 a

24 0

45 a 29 7

64

56

54

49 2

4x'9

36 5

32 5

28-0

161

162

158

I46

142

132

I : ' 2

98

37'6

32 4

25 2

24 3

22. 4

2I. 5

19'9

t9 9

19'0

19 0

X9 I

18'4

19 o

19 9

19'8

19 2

20.6

23.6

i2I

1o3

Io3

99

83

76

69

66

54

36 0

43 I

36.1

29 6

142

t44

I33

143

138

I3o

I3o

Io3

156

156

13o

15o

Distance downstre am of Breskens.



584 P . S t o . f f y n - E g l i

~

180

160

140

120

I 0 0

8 0

6 0

4 0

2 0

1

0 5 I0 15 20 25 30 35

S(31init~' ( o)

Figure 3- Dissolved Li distribution t s. salinity in the St. La wrence estuary. A total

o z44 samples were collected within a salinity range o f o'o4-35~oo rom 26 Aug ust

to z September z979. Tw o sampling stations were occupied during a whole tidal

cs'cle. The dilution line is shown.

n o t co i n c i d e w i t h t h e d i l u t io n l i n e ( s ee F i g u r e 4 ) . T h i s d i s c r ep an c y b e t w een t h e d a t a p o i n t s

an d t h e d i l u t i o n l i n e co u l d b e e l i m i n a t ed i n t h e ca s e o f t h e M ay s u r v ey [ F i g u r e 4 ( a) ] i f a

seawa ter L i : CI r a t io o f x I 3 lag L i g - i CI (ins tead of 9 35 lag L i g -1 CI ) i s used to def ine

t h e d i l u t i o n l i n e , b u t t h i s v a l u e i s u n u s u a l l y h i g h f o r s eaw a t e r ( C h o w & G o l d b e r g , x 9 6 2 ;

R i l ey & T o n g u d a i , I 9 6 4 ; F a b r i c a n d e t a l . , x 9 6 6 ; A n g i n o & B i l l i n g s , i 9 6 6 ; M o r o zo v , i 9 6 8 ;

E g l i, I 9 7 9 ) . M o r eo v e r , d u r i n g t h e J u n e s u r v ey [ F i g u r e 4 ( b ) ] t h e d a t a p o i n t s f r o m l o ca t io n s

I an d z ( t h e l o w e r m o s t s am p l i n g p o i n t s o f th e s u r v ey s , s ee F i g u r e z ) , w h i ch h av e s a li n it ie s

h i g h e r t h an i n t h e p r ev i o u s s u r v ey , p l o t c l o s e r t o t h e d i l u t i o n l i n e , s u g g es t i n g t h a t t h i s

l i n e is co r r ec t . T h e d i f fi cu lt y i n s am p l i n g an d d e f i n i n g t h e p u r e s eaw a t e r en d - m em b er i n

t h e S eh e l d t e s t u a r y s tem s f r o m t h e f ac t t h a t ( i ) d o w n s t r eam f r o m p o i n t I ( B r e s k en s ) w h e r e

t h e e s t u a r y w i d en s co n s i d e r ab l y i n t o t h e N o r t h S ea , m i x i n g b e t w een f r e s h an d s ea w a t e r s

s ti ll o ccu r s an d ( i i) ev en i n t h e ' o p e n ' s ea ( S o u t h e r n B i g h t o f t h e N o r t h S ea ) s a li n i ty is

v a r i ab l e an d o f t en l o w f o r s eaw a t e r b ecau s e o f i m p o r t an t r i v e r o u t fl o w i n t o t h i s n a r r o w

ar ea o f t h e N o r t h S ea ( P e t e r s & S t e r l in g , I 9 7 6 . F o u r w a t e r s am p l e s w e r e co l l e c t ed in

F e b r u a r y x 9 7 8 d o w n s t r e a m f r o m p o i n t x , b e t w e e n B r e s k e n s a n d O o s t e n d e , a n d s h o w e d

t h a t t h e h i g h e r t h e i r s a l in i ty , t h e m o r e t h e i r L i : C I r a t io a p p r o a ch ed t h e v a l u e o f 9 3 5 lag

L i g - 1 C I ( s ee T a b l e I ) . T h e l a st s am p l e , co l le c t ed o n t h e B e l g i an coas t n ea r O o s t en d e h ad a

s a l in i t y o f 2 9 . 7 ~ o an d a L i : C I r a t i o o f 9 . I z lag L i g - 1 C I . T h es e s am p l e s f u r t h e r s h o w

t h a t t h e d i l u t i o n l i n e i n F i g u r e 4 i s co r r ec t an d t h a t t h e d i s c r ep an cy b e t w een t h i s l i n e an d

the da ta po in t s i s r ea l .



D h s o l v e d l i t h h m t i n e s tu a r h t e w a t e r s 585

L

/

180

160

1 4 0

120

I 0 0

8 0

6 0

4 0

2 0

180

160

1 4 0

120

I 0 0

8 0

6 0

4 0

2 0

o )

_ . , , / /

; / /

/ j / / ~

ps I /

I I 1 I 1

0 35

b )

I 0 15 20 2 5 30

Salinity %0)

F igu r e 4 . D i s so lve d L i d i s t r i bu t ion v s sa l i n i t y in t he S c he ld t e s tua r y f o r ( a )

the M a y x977 su r ve y a nd ( b ) t he June t977 su r ve y . D ur in g e a c h su r ve y 39 s a m p le s

w e r e c o l l e c t e d du r ing the l ow t i de pe r io d w i th in a s a l i n i t y ra nge o f o ' 5 8 - z 7~ 0.

Th e d i lu t i on l i ne i s show n ( so l id l i ne ) . Th e da she d l i ne s a r e t he r e g r e s s ion l i ne s

f o r t he da t a po in t s o f e a c h su r ve y ha v ing a s a l i n i t y be low 25 5~o0 . Th e c o r r e spond ing

cor re la t ion coeff ic ients a re 0 997 (39 da ta poin ts ) fo r the M ay su rvey and 0 996

( 35 da t a p o in t s ) f o r t he June su r ve y . S e e t e x t f o r e xp la na t ion o f num be r e d po in t s .

B e c a u s e t h e r e s i d e n c e t i m e o f r iv e r w a t e r i n t h e S c h e l d t e s t u a r y i s o n t h e o r d e r o f z

m o n t h s ( 3N o l la st , x 9 7 3) , t h e o c c u r r e n c e o f a h i g h e r L i c o n c e n t r a t i o n i n r i v e r w a t e r p r e v i o u s

t o t h e s u r v e y f o l l o w e d b y a p r o g r e s s i v e d e c r e a s e w i t h t i m e o f t h i s c o n c e n t r a t i o n d o w n t o

t h a t o b s e r v e d d u r i n g t h e s u r v e y c o u ld c a u s e t h e L i d i s t r i b u t i o n o f F i g u r e 4- H o w e v e r ,

t h e r i v e r w a t e r w o u l d h a v e h a d t o c o n t a i n b e t w e e n z z o a n d z 9 3 l t g L i 1 - 1 ( d e p e n d i n g o n

w h e t h e r t h e s e a w a t e r e n d - m e m b e r s a l i n i t y i s 35 o r 3O ~oo) i n o r d e r t o c a u s e a c o n c e n t r a t i o n

o f z 6 z l ag L i 1 z i n e s t u a r i n e w a t e r o f 2 5 - 4 ~ o s a l i n i t y [ p o i n t z , F i g u r e 4 ( a ) ] . I t i s n o t l i k e l y



586 P . S t o f f y n - E g l i

t ha t such a h igh concent ra t ion ever occurred in the Scheld t River , espec ia l ly s ince two

su rv ey s , x m o n t h ap a r t , i n d ica t ed t h e s am e co n cen t r a t io n i n t h e r i v e r w a t e r s ee T ab l e x ).

S ince the d i lu t ion l i ne of F igure 4 i s correc t , t he fac t t ha t t he da ta po in t s p lo t above

t h i s l i n e i s ex p l a in ed o n l y b y t h e ex i s ten ce o f an i n p u t o f d i s so l v ed L i i n t o t h e e s t u a ri n e

waters . Because the da ta po in t s i n F ig ure 4 p lo t on a s t ra igh t l i ne for sa l in i ti es be low 25~o

d ash ed l in e s ), t h e d i s t r ib u t i o n o f d i s so l v ed L i i n t h a t p a r t o f th e S ch e l d t R i v e r e s tu a ry

m u s t b e t h e r e su l t o f p h ys i ca l m i x i n g b e t w een r i v e r w a t e r an d an i n t e rm ed i a t e en d -m em b er

of ap proxim ate ly 25Yoo sa l in i ty and con ta in ing x53 to x6x pg Li 1-1 Boyle

e t a l .

I974;

Bu r ton , I976 ) . I t i s p robable tha t t he d i sso lved Li d i s t r ibu t ion a t sa lin it ies h igher tha n

Z 5~oo i s d e t e rm i n ed a lso b y o n l y p h y s i ca l m i x i n g o f t h e i n t e rm ed i a t e en d -m em b er an d

seaw a te r , a s su g g es t ed b y p o i n t s x an d z o f F i g u re 4 b ) . T h e i n t e rm ed i a t e en d -m em b er

m u s t b e cau sed b y a v e ry l o cal iz ed in p u t o f d i sso lv ed L i , p ro b ab l y i n t h e v i c i n i t y o f p o i n t 3 .

T h i s ex cess L i w as ca r r ied d o w n s t r eam p o i n ts 2 an d x ) w i t h o u t m u ch m i x i n g w i t h

seaw a t e r in M ay [F i g u re 4 a )] w h e rea s ad m i x t u re o f s eaw a t e r d il u t ed th e exces s L i d u r i n g

t h e Ju n e su rv ey [p o i n ts 2 an d i , F i g u re 4 b) ].

In an a t t em p t t o d e t e rm i n e t h e cau se o f t h e d is so lv ed L i i n p u t , I p e r fo rm ed l ab o ra t o ry

ex p e r i m en t s w h i ch sh o w ed t h a t su sp en d ed m a t t e r i n t h e e s t u a ry can n o t r e l ea se L i i n t o

so l u t io n i n an y s i g n i fi c an t am o u n t an d t h a t ad so rp t i o n -d eso rp t i o n r eac ti o n s w i t h c l ay

mine ra l s a re negl ig ib le in the case of L i . Col t en I98o) a r r ived a t t he same conclus ion on

t h e b a s is o f m easu rem en t s o f ad so rb ed L i o n su sp en d ed m a t e r ia l i n t h e M i s s is s ip p i R i v e r

e s t u a ry . T h e m o s t l i k el y cau se o f a l o ca li z ed i n p u t o f L i i n t h e S ch e l d t e s tu a ry i s n o t a

n a t u ra l m ech an i sm b u t a m an -m ad e i n p u t . T h e S ch e l d t e s t u a ry i s l o ca t ed i n a d en se l y

indus t r i a l i zed a rea wh ich causes cons iderab le po l lu t ion of t he es tuar ine waters W ol l ast ,

I9 7 6) . I t i s t herefore ve ry probable th a t i ndu s t r i a l ac t iv i ty re leases L i - r i c h was tes a t a

p rec ise p o i n t a l o n g t h e e s t u a ry . U p s t r eam an d d o w n s t r eam f ro m t h is an t h ro p o g en i e in p u t ,

d i sso lved Li b ehaves conserva t ive ly in the S cheld t es tuary , as i t does in the S t . L aw rence

es t u a ry . In a r e cen t s t u d y o f di s so l v ed L i i n t h e M i s s i s si p p i e s tu a ry , C o l ten t 9 8 o ) a r r iv ed

a t s imi l a r conc lus ions : d i sso lved Li shows a conserva t ive behaviour in the l~ l i ss i ss ipp i

e s t u a ry ex cep t i n t h e v i c i n i t y o f N e w O r l ean s w h e re r em o v a l o f L i f ro m so l u t io n i s b e li ev ed

to be caused by reac t ion wi th indus t r i a l o r munic ipa l was tes .

Conc lu s i on

T h e d i s t r ib u t i o n o f d i s so l v ed L i v s . sa l in i t y i n t h e S t . L aw ren ce an d t h e S ch e l d t e s t u a ri e s

su g g es ts t h a t t h i s e l em en t b eh av es co n se rv a ti v e ly d u r i n g m i x i n g o f r iv e r w a t e r w i t h s ea-

water . However , t he ex i s t ence of a l oca l i zed source of d i sso lved Li i n the Scheld t es tuary

i n d i cat e s t h a t an t h ro p o g en i c i n p u t s m a y s i g n i f ic an t ly a f f ec t t h e L i co n cen t r a ti o n o f e s t u a r in e

waters i n dense ly indus t r i a l ized a reas .

c know l e dg emen t s

I t h an k D r F . T . M ack en z i e fo r h e l p fu l d i s cu s s io n s , D r R . W o l l a s t fo r p ro v i d in g t h e o p p o r -

t u n i t y o f s am p l i n g t h e S ch e l d t e s tu a ry an d D r P . A . Y ea t s w h o su p p l i ed th e S t . L aw ren ce

e s tu a r y sa m p l es . T h i s r e s e ar c h w as f u n d e d b y U . S . N S F g r a n t 7 6 - i z z 7 9 w h i l e t h e a u t h o r

was a t No r thw ester n U nivers i ty , I l li no i s . I a lso gra t e fu l ly acknowledge financ ia l sup po r t

f ro m a g ran t fo r D ev e l o p m en t o f R esea rch an d a K i l l am P o s t d o c t o ra l F e l lo w sh i p aw ard ed

b y t h e F acu l t y o f G rad u a t e S t u d i e s o f D a l h o u s ie U n i v e r s i t y .



Dissolved lithhtm in estuarlne teaters 587

e f e r ence s

Angino, E. E. Billings, G. K. x966 Lithium content of seawater by atomic absorption spectrometry.

Geochimlca et Cosmochimica Acta 3 o x53-x58.

Boyle, E. Collier, R., Dengler, A. T., Edmond, J. M.,

Ng,

A. C. Stallard, R. F. x974 On the

chemical mass balance in estuaries. Geochlmica et Cosmoehimlea Acta 38~ x7x9-x7zS.

Burton, J. D. x976 Basic properties and processes in estuarine chemistry. In

Est,tarine Chemistry

(Burton, J. D. Liss, P. S., eds). Academic Press, New York. pp. x-36.

Chow, T. J. Goldberg, E. D. x96z Mass spectrometric determination of lithium in seawater,

ffournal

of Marine Research zo~ x63-x67.

Colten, V. A. x98o The behavior of lithium in the Mississippi River estuary. Master Thesis, Louisiana

State University. xz3 pp.

Egli, P. x979 Cycling behavior of dissolved lithium in the oceans. Ph.D. Thesis, Northwestern Uni-

versity, x75 pp.

Fabric'and, B. P., Imbimbo, E. S., Brey, M. E. Weston, J. A. x966 Atomic absorption analyses for

Li, Mg, K, Rb and Sr in ocean waters..7ournal of Geophycisal Research 7x~ 39XT-39zt.

Hanor, J. S. Chan , L. x977 Non-conservative behavior of barium dur ing mixing of Mississippi River

and Gulf of Mexico waters. Earth and Planetary Science Letters 37~ 245-25o.

Morozov, N. P. x968 Geochemistry of rare alkaline elements in the oceans and seas.

Oceanology 8,

x69-I78.

Peters, J. J. Sterling, A. x976 Hydrodynamique et transports de s~diments de l'estuaire de l'Escaut.

In Projet ICier, Volume xo--L Estuaire de l Escaut (Nihoul, J. C. Wollast, R., eds). Programme

National de Recherche et de D6veloppement, Belgian Government Publicat ion, Brussels. pp. x-7o.

Riley, J. P. Tongudai, M. x964 The lithium content of sea water. Deep-Sea Research Ixj 563-568.

Russell, K. L. x97o Geochemistry and halmyrolysis of day minerals, Rio Ameca, Mexico.

Geochimica

et Cosmocimiea .4eta 34, 893-9o7.

Sayles, F. L. Mangelsdorf, P. C., Jr. x977 The equilibrationof clay minerals with seawater: exchange

reactions. Geochimica et Cosmochimica .4eta 4x~ 95x-96o.

Wollast, R. x973

Origine et Mgchanismes de l Envasement de l Estualre de l Escaztt.

Laboratoirc de

Reeherches Hydrauliques, Borgerhout, Minis tbre des Travaux Publics, Belgian Government

Publication, Brussels, x4o pp.

Wollast, R. I976 Transport et accumulation de polluants dans l'estuaire de l'Escaut. In Projet 2~ler,

Vohtme xo--L Estuaire de l Eseaut

(Nihoul, J. C. Wollast, R., eds). Programme National de

Recherche et de D~veloppement, Belgian Government Publication, Brussels. pp. I9x-zx8.

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