-',.-'l

:::1,'.''

::

:

:::

'.

!p.grig:

9iversi!I

I

The

objectives

of

this

analysis

were

to determine:

ii

)

*h,:ther

the

rrr)vprntril

rf

COOling

waters

promOtes

d

Constancy

Of spectes dire

rs

r

ty

rn

ilrc

o;ten-itdter

regions

of

the cool ing

logp,

and

(2)

whr:ther

diichir-rJe Hdter

tem;ierdIrres

anil

associated

conditions

during

late

sunmer

reduce

diver*i-y

rlurirrq

Lrrlt

period.

0i

vers

ity rtata

f rom Year

I

ranged

f

rom a low

of

.'1.46

nt

Srat

ion

j

rn

0ecember

1978

to

3,ll

ot

Station

4

in

June

1979;

the

widest

range

of

values

generally

occrrrred

at

those

two

stations

throuqhout Year

I

{Tab'le

6.3).

The

overdll

rrrean

diversities

in Year

I

of all

stations

each

month ranged

frcrn

l."il

...

'.67

with

an

average

of

2.11.

itonthly

means

of

coolino

loop

stations

ranqed

from

l.65

to

2.8

with

a

mean

of 2.15. For

Stations

3

dnd

4

combined,

I,ne

range

was

sli3htly

greater

at l.l0

to 2.83.

An

analysis

of sequential

trends in

tne

coolino loop

each

month in

Year I

showed

that,

with

the

exceptions

of

llovemher

and

June,

populations

in

the warmest

regions

of the

loop

(the rJischarge

and Station

!) nad

the highest

diversity

values.

In

general,

however,

there hrere

no

easily distin-

guishable

month-to-mont.h

trends

of ei

ther

constdncy

or

increases

arrd

rJec

|

-neq

in

species diversity

in the direction

of water

flow.

A

comnarison

cf

mean

diver-

sity of

stations 3

and

4

and

the

cooling

stations showerJ'that

mean cJiversit.ies

were

general

ly

oreater

at

stations

clirectly receiving

thermal

efflgents.

.

r

:'

j"'

'

In

Year

2,

species

diversities ranged

from

0,2?-

at

Stotion

2

in

January

l9B0

to

3,26

at Station I in

Jrrne

1980,

Lakewide mean

diversities

eoch

rnonth

r.rnged

from 0.50

to ?,61 in Year ?;

stations

4

and ?

had the hiqhest

and

lowest

annual

meanr

respectively. A

comparison

of

the mean divelsity,

ofrstations

3 and

4 with

that

of the cooling loop

stations

in Year

?

showed

that'locations

closest

to the

discharge had

the

highest diversity

in August

and

September,

when water

tempera-

tures were highest.

Apparently,

h!gh rlater

temperatures were

less

detrimentol

than

would

be

expected according

to the

literature

(Pennak

19lB). Therefore,

loc.at!-on.s-!ayj.ng

later

temperatures

exceeding

30'C

(which

is

a

lethal

level

for

rnost

zooplankton

g-ccordf

ng to

Pennak

(19i8))

were able to

support

viable

,!:'l-

*

-t

-

.

-'*-.

,zoqp,la1kto1

cormulities

,in.terms

of

richness

of spacies:.,

It

is

postulated

that

,,i

targe

portion

of

the, late'.Sumlner

community

was

residing

below

the thermal

'plume,

(Section

2),

particularrly

in deeper

regions

upstream

of the dam,

where

I

I

I

I

I

I

T

"

"l'

..,

r:.,

,l

'.i

,,.I

6.10

---

r\J

c

(1

o

+J

.J

a/l

E

g

,t|

(lJ

ttt

L

,\t

(J

E

0.,

-v

(l

c

OJ

\)

(J

c

f<

aJ]

o',

lci

€\.

.

Gt

{\,

ot

(c

.:t

rc'

{f

f)

o

qt

ri

F!

a

H

(f)

O

{\t

ca

(v

(\,

\.o

c1

C\l

c'l

fr\

'\;

<t

o'

O.\

Cv

\9

GJ

co

i7)

R

o\

O

(o

!t

rt

rc}

(o

(\J

(o

(\,

C\J

c'\

(v

ro

(\J

Ctt

\rt

r€|

cll

O

o:

(n

cv

f')

(o

f')

(v

c

1

c)

r'-)

.it

J

@

<f

cv

(\..,

r{

(\J

rn

<t

c\J

O!

t\

o

(fr

9!

.1

I

qr

|"\

c'.l

I

N

E

LU

(\J

cr..

(\J

<t

6J

t\

rs'

cv

C\J

r/)

G;

a7)

?

(\,

r\

rt

d

a

(o

Ot

.-r

(\,

c)

O.;

rt)

c\t

N

('r

r4

f\J

-1

c

a.i

(\i

(r.l

@

f\J

t\

G;

ct

G.l

c\,

AJ

6J

4

(v

(\,

a\

-1

o

ri

(o

(f,

$J

@

(v

ro

4

(v

d

(\,

o

(o

N

a

f\,

a?)

(\J

c)

c9

(\J

(\,

cv

<l

7<

C\J

o\

cv

(o

ro

a'1

N

.{

Ol

(\,

N,

C\J

F{

Cv

tJ)

r.o

F<

gr

or

I

r\

coOl

I

E

UJ

El

sl

-l

j

'?

:

iF

1.,

lr!

t

O

.:

@

Or

a4

(u

c

5

'?

E

c'l

o

L

t

P

@

F\

O!

>1

F)

3l

c,

-x

rtt

J

(l'

c

(u

$-

$-

o

C).

c

c

1)

o

.v

g

r!

P

O..

o

o

l+,

o

(l):,

t

|!

,|,

>.

t^

L

qr:

o.

(v'

rO:'

o'..

4lri

|!':r

F ...

E

ql

vril'Crt

F

(U

I

C

I

O

FE

''?{

.F

t)

G

CFO,

,rJ

O

()

rd

tr+JC

L(u

'o

il,

(UJ

(u00

(u4r

>'o

=(JJ

:

!f(/tco

o-j

.ta

Qrt

c

rt

.

rcro

.Fl

,F,p

@

C-

A

g€

E

L C

i!

o o

d

o.o

o

(l,

o

o

Gr.rJ

>

^t

o

=

(JJ

Evtcrt

o=

6.

11

':

---

stratif ication

yts

evirie*t,'lince

the

entire

watr-.r

csluqin,i{is

rarnpled

.in

lhese

aredsr

the

high

divergity

nray

have

prevailed

regaritlass

of

the

pirsencc

of

t.he

Harmwdter

layer.

There

Here

very

fer:instances

in

ei[her

gr"adually

increased

or" decreased

in

the

loop;

in

most

instances

the data

were

annua

I d i vers

i ty

of

zoop I

ank ton

corrnun

I

and Year

2

(1.95)

yas

within

the range

a

3-year mean

for

Lake

Sangchris

(2.13)

Lake

Shelbyville

(lJaite

1979a).

ABUI{DANCT

OF

I-|AJOR

ZOOPLAI{KIOI{

GROUPS

study

year

where

spec i e:l d

i

ver

s

i

ty

direction

of

rater

flow

in

tlre cooling

extrenely var

i

able.

0vera l

l

,

the

mean

ties in

Coffeen Lake for.

Year I

(2.11)

of variation

expected

and was

simi

lar

to

but

lower

than

the

2.27

computed

for

A

fami

liar

characteristic

of freshyater

rooplankton is

the

extensive variabi

I ity

of orgdnisn density,

both

sedsonally

and spdtidlly. Typical

curves

of seasonal

abundance in

most

temperate lakes

consist

of a late

spring

pulse;

a smaller

pop-

ulation

during

late

surrmer;

d second,

but less

pronounced

pulse

in

autumn; fol-

lowed

by

a

reduced

population

in

winter. In

Coffeen Lake, it

was

rluestionecJ

whether the

physicochernical

parameters

associated

with heated

effluents

rniqht

alter

or

produce

atypical

trends in

the

seasonal

abundanc€ of rotifers,

clado-

cerans, and

ccpepods.

Eqlirrrq

The

absolute

abundance of

rotifers

in

Year I

was

monocyclic

at

all

stations in

mid-sunmer.

Front

that

period,

numbers

gradually

decreased

to

winter-tirne

lows

of

approximately

1,000

individuals r-3 in

the

cooling

loop

and

20

times that

number at

Station 4. In FebruarJ,

populations

quickly

recovered

and

gradually

increased

from

301000

to

50,000

organisms,n-3 in

April; in l4ay,

however,

fish

predation,

species succession and the

complete shutdown of units I

and

2

at

the Coffeen

Generratin-g Station

(Fig.

l.l)

probably

accounted for

the decrease

in

abundance.

6.12

---

I

:.-l='

-l

.l

'l

:'

'l

I

,,1

'

:i

I

i

:ii

Jl

-l

.'l

There tere fetr

trcndr

in

Year

I

regorrJinq

lhifts

in rct!fer

abundonce

in

'rhe,.

cooling

loop

each

n

nth.

Rotifer

numbers vrsre

variahle

fron

thc

iiisrharqe

lo',

intake;

numbers

at the

coolinq

loop

sLations, howeverr

wcre

eene,'ally

nnre

than

those at'stations 3

anrj 4

frorn May

through

August,

0ur'ing

Year

l,

ro[ifer

i

'

densities in

Coffeen

Lake

rere invcrsely

proportional

to

the distance

from

the

'

discharge

canal. Station 4

favored

the

rieveloprnenl

of

more

littoral

species,,,

many

of,

which

attained

relative'ly

high

rleosities

(?5,000

to 140,000

m-31

,

'

ln

terms of

relative

abundance, rotifers

lakewide in Year I

constituted

75

to.

9BI

of tota I zoop I

ankton

numbers

in Ju ly;

irr

Novemlrer through January,

that

fraction,

wds

reduced

to between I

and

BOX

in

the

cooling

loop

and 33 to 94{

:

at stat'ions 3

anrJ

4

{Iable

6.4), The

annual

mean

percentdge

of

rotifers

for'

each

station

in

Year

i

progressively

increased

in

the dlrection

of

water

flowr

from

4lX

at the discharge to 57I

at

the

intake,

with

6i and

77fl, respectively,,

at

Stations 3

and

4.

'

t{hile rrotifer densities increased

progressively

with

:

distance from the discharge, the fraction of Lotal zooplankton tha't

constituiecJ

this

group

was

also

larger,

'

It

is

apparent that with

in

the cormuni ty structure

at

'various

po'ints

f

rorn

the

discharge,

rotifers

had

relatively less

tolerance

of either

discharge tempera-

tures'or

current

velocities,

both

of which

decrease at

points

downstream

(s'ee.

Section 2).

''

a-

.

.

:

-

During

Year

2,

the largest

lakewide

pulse

of

rotifers

occurred again

in

July

(45,000

to

145,000

organisms

m-3).

The

total density

then

gradually

'.,,

decreased

to an early winter

low

of

0

organisms at all

stations

except

Station

4,

As.winter

pr^ogressed, populations

quickly

recovered,

and

densjties increased

at all stations

through spring.

A second

major

pulse

was detected in l4ay.

This

trend

t1as

similar

to that

of

Year l,

except

the

sprinq

pulse

in Year

2 occurr.ed

I

rnonth I ater.

:

'

-",,

.i,'

For the

period

September to

0ecember

1979, densities

at

Station,4

exceeded

those

of

the

cooling loop

stations

by

l.t

to

7.6

tirnes.

A,

jgJgg-t-qed--tglY.gl

l-,

!pt4{=!ggiclt-

Oifferlqc-sr-el*thLJake

at

Station

4

were,

probabll-rr'.re

le-vqfi.b*le

fgfje-99f._lgfgglg-itJy.p.lc:l'ltll-.t-1n..

It is doubtful that'the

atypical

)y

'l

5."13

---

t

T

I

I

I

I

I

I

I

I

T

T

I

I

I

I

I

.a-..'ir,.,'...1:'

i,.'

.'

:

i:'::::.

: a'

ii.

',

,';:,;,t,

.

;

.,1

'

ll,.."'

Ir!!e-6.4,

Per(enttqe

relatfye

abuodrn{e

ol

t.raJor

r^Jgl6nttqa

qrosrl

i,r

tof{t:tn t.rte,

'jul_y

l9/g

ttrouqh

June

1980.

ii,

:qfs

It=s:a.-F,.*-&;.:E--]tt:J,4:@.l{fq

t7

()l

{t? 47

5

lb

,

.,49

8

!

.,

t

7

6

I

44

6

'

3

I

)7

I

!0

?l

?4

'

l0

?9 55

lt

.75

l0

3:

"4

/

16

4

..8

7t

72

It

80

,61

'5533

|

?

l0

3

,5

18 15

49

9

17

I

4

15

?

4

89815545?5762e7081s69t958

6 l2

lB

5

3

I

6

|

:I

I

6

S

6

!

I

-2

3

12

I

34

6

't

6

16

3

I

35193449.Ic?4?t13245310??

|

?

6

t?

il

5

I

?

1

6

75

3

6

76

4?

14

:6

4

,

ll

39

30

17

'lt

45

45

45

3

'8

46

.J6

3

:.

6

73 62

t?

34

2?.

28

l4

3

.{3

11

.

6

410

41

37,

l?9

YtA!

I

.

l9rS-19t9

ilearr

-

Loollnq

toopl

Rntiterc'

86

16

42 43

5

09

Cladocera

7

16

23

.'6

5

.

CopepodoI'3615g

'

ittitpl

| |

5

5

24

,30

6l

15

:Copepodld.l3SlS14l

tlqan

-tstatfons

J rnd 4

''

'

Rotlferd.

96

9l

il

J9

53 8j

St

e0

Cladqcera

3

5

8

3

I

'

,?

.

Conepodrr.266145

,tinupltl

.

J

I

,{l'

24

3

re

n

Copepodfda'126821?

0verra I I llea.n

flot

i

fera,

C I adocera

.Cope.noda

.Nrriplii

Gopenod

i da

ir';'

l,

. .

;:. .

i1l

:

ljt'

1.,'

i:,'

.

'

i:.

L.

::,

i,,:,

?iit,,",'

i:.

j:'.

, .

i':''.

:

.';:l

.

,?:'

:.

tt:;:

'

i:,t'.t

j

t::.

,

'ii

ii',

:

i1::

il'-,

!.','.

::..

I

ti,

;'.',

i't:

,,,,

'1;;,:

,

,:'

!;.il.

.

'

ii'

'

Jb

.tJ

?7

l2

33

2

9

48

8

61

84

45

ll

I

5

6:

,l

I

15

l?

?o

4227

t9

Bt

56

,81

5t

4

I

13

..l

4

?96926

37

l0

19 15 z3

ll

?

3

I

16

YIAR

2

-

l9t9-198n

lt:

f{ean

-

Coolinq

Loop'

Rotifera

87

44

13

3

:

0

17

82

Cladocera

3

4

l8

4:

5

5

I

Copepoda,

I

7

7

ll

J7 ?8

5

f{auplli

6

35

52 69 31 40 ll

Copepodida

3

l0

1l

13

28

ll

3

tteg_:

L L_l!.q_g

,

41

I7

I3

?l

Za

80

ll

3?9

1?

O

102

33lBs4

B I?

4.

4

53814

44

43

7?

60

l0

s

ll

l9

402141

6164^

6510?9

38

49

70

4l

l09l?25

Rotiferi.,:

92

Cladocera:"...

,

4

Copepoda

'

0

Naupfii,

4

Copepodida

0

q,:lsgf.*

RotifCra

88

Cl

adocera

4

Copepoda'.

I

Naupl

I

l'

5

Copepodida

?

35

?

ll

iil

ll

:-.-::--._--_

Ilncludes

Intake,

dJscharge,

and

Statlons'I

rnd 2

i

'

,

*less

fhan I

pcrcent

l

.

6.14

'l

---

,'l:':

r

:,1:t1:.::

a

,',:

high water

temperatures

in Coffeen

Loke during

ldLe

sunmer

of

1979

seriou:),v

,l

irnited

r-otifer

prqdqstiqn,

iince

many

of the

hiqhest densities

(99,000

lo

1

145r0{0

orgarrisns

rn'J}

r6ra

iri

th€

r€gi6n

of

iffiedidic

dischdrde

during rniC-

tn

];?F-=ii}ffiF,

In

terms of

the

highest

relative

abundance

in

Year

2,

rot'ifers

lakewide

consti-,:

tuted.72toi95tofthetota]zooplanktoncofimunityinJuly.Thefractionof

rotifers

Has

smnllest,during

0ctober

through

Dscenrber 19i9

(<20I)-

0n an annuel

.basis,the.rneanpercentageofrotifersforedchstdtionincreasedfromi4lit

the ctischarge

to

50fr

at Station

? and then

clecreasecl

gradually

to 48,46, and

4-?i

of

the intake,

Station

3,

and

Statisn

4, respectively.

An unusual

situation

oeeurred

in Hovember

1979

when

rolifer"*

constituted

0t

of

the total

eor;munity at

all sampling

locations

ereept

Station 4-

Horever,

ij."f

fr":..9J*jle.,JiltglJ

.

g[Lsjggglgmlgg]

"pgr.q!qe.t-e-rs

!^e-vedled

-no

.a-tvp.ica-]

,cqnd!tigns

dur:ins autumn

and,

thus,

n0 implication

0f th€

plagL*t_q!gf.q!l9n:

L.,-qro-*eu'-

e lad-ae:eta

,:The

abundance

0f clddocerans vtas lowest of

oll

stations

frQrn

December

through

1

llarch

of Year I,

with densities

ranging

from 17

tq 1,492 orqanisms

m'r, By

April, abundance had

gradually

increased,

averaging

appr'oximately

4,000

organ-

:'

istns'm-3

lakewidel

by

September,

densities

hid

peaked

at

10,000

organisms

n

rn-3

et

.

Station 4 to

55,000

organisms

m-3 at Station

?, 0n

a

rrnnthly

basisinYearl,.therehJerenoconsistentincreasesordeclinesinthenumbers

of

cladocerans

arqun<J

the cooling

loop, Cladoceran

densities

at

stations 3

arrd

4 were

less then those of the cooling loop

stat'ione from

May

through 0ocembor,

g!'eater

in. February,

,and

virtual

ly

ident

ical

in Janrrary

and

l{arch

through

Apri

1.

Annual

means

sf cledoc€ran abundarie€

at- eaeh.-tati6n

in

Year

i

gencFaiiy

decreased around

the

cooling loop from

discharge

to

intake,

and

likewise,

at

.stations

3

and

4.

Gladocerans constituted

a

relatively

small

percentage

of

total:zooplankton'for

'

Year ?; the

range

was

0

to

271 with

an

overal)

average

of 6I. 0n

a mean lake-

wide basis, the largest

percentages

occurred.,.in

August

1979

(16{),

February

1980

(l3t),

and June

l9B0

(1lI);

the

lowest

percentages

were

in

Ma-v l9B0

(2*).

.aa= |

6, t5

---

January.,l9B0

(lI),

and l,larch

l9B0

(1f,).

the.fraction

of cladocerans

at e,rch

station

on

dn dnnudi

basis

in

Year

? decreasetJ

frorn

BI

at

the discharge

to 51 at

Station

2 and the intake.

The

percenta0e

hras lower

yet

aL

Station

3,

hrrt

ilre

mean

at,:station

4'was

equivalent

to

ihat of

Station l.

.

The

lakewide

abundance

of cladocerans

in

Year:'2

was

lowesL

fr"om

llovember

through

frlarch,

compared

to Oecember

through

Flarch

in

Year i

.

I

n

January,

February, ,]nd

l*larch 1980,

al I

densities

were

less than 500 m-3

.

8y

Apri l,

abundance

increased 4-

to 100-fold

(depending

on tha

location), averaging approximately

1,550

organisms

m-3. As

in

Year l, the

peak

in

Year

2 occurred

in

September,

with

densities

ranging

from

6,000.tb 15,000'orqanisms

m-3. 0n

a

monthly basis, densities were variable around the cooling

loop.

0n an

annual

basis, the

mean abundance of cladocerans

generally

declined

frorn

the

discharge

to the

jntake,

and

stations

3 and

4,

eroctly

the

sorm

ds was

found in

Year l.

...

a^-^^^l-

uopepoda

The copepod fauna

in

Coffeen

Lake

was

the only

major zooplankton

group

to

exhibit

two

pulses

in

Year l. Nauplii,

copepodids,

and

adults

were

present

in

low

concentration

in February;

qradually

increased

to

a

peak

in

May;

decl

ined in

.JuneandJuly;andbeganincreasingjnAtrgusttoreachasecondpeakin

Novernber.

Adults

were

greatly

outnumbered

by the irnnature

sta.r;es;

in

all

but

three

collections

in

Year t,

nauplii

and copepodicl

densities

surpassed

the

mature forms

by up

to

960 times.

During individual

months

in Year

I there were

few

distinguishable

trends where

copepods

increased

or

decreasedr'around the

cooling'loop.

However,

the annual mean

of

Year I for each station showed

that,

while

the density of

mature

forms was

variable

around

the cooling

loop, the

numbers

of

nauplii

and

copepodids

were

relatively

equal.

All forms

at stations

,3

and

4 werc

present

in

virtually equivalent

densities, but their numbers were

'greatly"ieduced.(40

to

50i)

when

compared

to those of the cooling loop.

The relative

abundance

of

mature

copepods

ranged fron

721

of

the total zooplank-

,ton

in

January

1979

at

Station

I to::approximately

1X

at thc

following:

(l)

all

stations.in

July

l978,

(2)

five

stations'in

August 1978,

and

(3)

two

statjons

jn

:'septembCr',1978,.-,,The

annual

mean

relative

abundance

decreased

from

the

discharge

-l'

.:

l

I

t

t

I

I

T

I

I

I

I

f

t:.

i.

.,

r:..

a,..,, .

'

t::t

:

i':'r,

i:::..

-

'-',:;::,'

.

Y;t::,.

.:.

i:'.i:',.,

..'

1i.i..

,.

i:-';-.1 :

r,-:1!,:

..

:

!?-iL'i

'

'

Lri;';.,;';

I

I.

:

I

l.'

I'

li

6. 16

---

'l

:,:

I:

to the

intake,(discharge,

stat.isns

I

and

7,

intake),

and

likewise to stations

3

and 4

(13,

10, 9,

7,6,

and 3I,

respectively).

Ihe

perccntagc

of nauplij

ras

virtually

the

same

throughout

the coolinq

loop

in

Year

I

whi

le

cooepodirJs

were

variable.

In

Year

2,

nauplii

and copepodids aga!n outnumbered

their.

adult

counterparts.

All

constituents

were

present

in

very

low

densities in February,(3i-63

organisns

a.

m-J).Beginningin.|,1arch,dens1tiesbeganincreasingaodreachedthe|r.

maior

peak

in

llay.

Populations'decreased

in

June

and

July

and

pedked

again

in

S_eptember.Ther|ensityofnaupiii,copepocJids,andmatureformswasvaria|rle

around

the

cooling ]oop'each month.

'.

The relative

abundance

of

mature

copepods

ranged from

01

at

Station 2

and

Station 4

in July 1979 to 6,21

at the

discharge

!1,November.

The Year 2

annual.

mean relative

abunclance,ctecreased

pr0gressively

frorn l5I

at

t.he discharge to BX

at

both Station 2

and

the intake.

0n

a

lakewide

basis

in Year

2,

nauplii

and

.:

copepodids were:variable,

ranging from

0

to

47fl.

Annualiy,

nauplii

percentages

rere virtually constant'throughout:the

lake

(25-36X

of

total

zooplankton),

whi'le

copepodidsdecreasertfromLhedischargetoStation4.

ZOOPLANKTON

BIOMASS

Although standing crop

biomass is

presented

in

terms

of

dry

and.gtn:lry-e_..-(!g.!at

ug.lg-ttlq*o-fg:n!-Q-[r.at]er) weight, the

latter was

preferred

when tne

contents of

some samp'les

were suspected

to contain large

amounts of sjlt,

cletritus,

or

slag.

:

'

n

In

Year l, ash-free

biomass

ranged

from

13

to

2lB

mg

tn-r

with

an

overall

:

a

tneanof53mgm.3.Forthemonths.ofJulyl97Bthrough.Jan]uary1979,ash-.

free

biomass decreased

progressively

around

the

cooling

loop

(from

Station

I

to

Station

2,

etc.).

In Fellruary

and

March

1979,

the

amount.s were'virtually the

same, while

during

the

remaining

period

biomass

l{as

quite

variable. The

annual

rnean

ash-free

biomass

for each sampling station

in

Year I

ranqed from 86

mq

t6

m-3

at

the discharqe

to

40

mg

m-J

at

the

intake.

For 421l

of the

time

(months

in Year l), the

lowest

values

were

at

Station

3,

while the highest

were

recorded

at

the

discharge

(7Ot).

A

comparison of

Station 4 data

to

those

of

6.t7

i

---

the

cooling

was

greaterr

August)

and

(

Table 5.5).

The organic

fraction,

described

here,ts

rlercentage

orgdnic

content' was vdriahle

fron

station

to

station and

month

to month

in Year

l. The monthly means

of all

stations

ranged

from

45

lo

721,

while

the annuai mean of

each

station was

50

to

741.

For

most

col leci ions,

the

organic

f ract

ion

increased_

algqq{.-!hg_.-.qo_o-.!-Ul.g

t:qp*trfL$r*::

ffis.--{!I._d{_i1I*lj9j

iiSI;;g..

Thar

fact may

1ef

|eet_

!|e

:_t_U,

clll*!..11I1-t*r-lrd-$:-s.lqs-p-er.t-:,culates-

il!r-o.9-!999

y.!.q.-L|'*e...l"qk

within

the

discharge

canal.

loop

stations in Year I

showed that

ash-free

biomass

in

the

former

than the mean biomass

of cool

ing

Ioop

st

at

ions

in

hoth

sumner-

(l,1ay-

winter

(0ecember-February),

but

less

in

dutumn

ancJ

eorly'sprinq

2 in

Coffeen Lake, the

a:la[rlrg:gfghl

.qlj_qqp-liln1tlon

ranged from

-3

with

an

overall

lake mean

of

3i

mq

nr-3.

These

amounts

are

30X

lower

than

those

recorded,

for Year l.

However,

a

comparison

values,

(tlaite

1979a)

shows

that,,!91_f

e-e1

.!{_9'.

v3lye!

.111e:

l_ow

on

a

t

I

t

I

I

I

t

I

t

t

T

I

I

I

I

During

Year

lt

to

126

m9 m

approx imate

I

y

to

other

,lake

Observation

of

the

annual

biomass means

for each

station in

Year

2

revealed

o

gradual

decrease

of

ash-free

biomass

from

the discharge

to the intake. Collec-

tively, the nean

of

these

coo'ling

)oop stations equalled

the

overall lake mean.

From

Juty

ttrrough November,

the biomass at

Statiorr

2 was

iess than that,

at most

stations:in

the

cooling

loop.

For

the

period

Oecember

to

June,

the biomass

at

each

station

in the cooling loop

was less

than

that

at

Station

4.

The annu-al'mean

percentage

of org'inic

biomass

'increased

by

smal I

increments

frorn

38X at

the

discharge,to 541 at

the intake in Year

2, suggesting that

heavier

inorganic

particles,

held in suspension

by the turhulence

at the

discharge,

progre.ssively settled

.out

as

the current velocities decreosjd

oround

the

cOoling

loop,

-

Th.-,

qgst.-pelggleg9_9fJl

.g-go_Li.?g,._lqgp.

*alig-ll

lgp

gsgentra.!!y.

gQual to

4*e

the aveia)l

---

lake

mean

relative

scale,

but

within the

ranqe-recorggg,

!q.f

!qlt_e-S

-!-q-pgchqis

an.d

She],bV-

vi I le from 1975

----#--::'

through 1978.

li

I

,l

5.lB

'l

---

r"

|'.

l'6

I|

r

,rt

lc

f3

lrr

Iru

lrr

Y

tg

l,l'

,

I

!oJ

I

cr)

t4

ls

ln

li-

fc

t.

lar

lv

l.s

t,:

I

lo

tg

la

.;

lcr

lc

giH

{l)

C,

ar

a]

<t l')

t+

rO

(\J

.}r

Hc)r

d--i

trl

(\J

sr

F--

O

CO

lO

\.o

ct

or

(\J

(f

dH

01

\O

(')

CD

<t

?'.-

ff)

1.. t-

.7)

' lir

r?)

ta,

tY,

r{|

rf

st st'

C\J

(\,

.t)

<t

,\

ocl

-1

€

at).{

c\J

o

cv

H

r-'l

rq

<ttrl

<t'

<l

r<'

co

(()

rO

it

f.\(.,

(o

@fo

st

rDs

<f

O!

aa

tr}

iJ

rr)

O

l.\('l

t..

cf)

tr)

(o

ro

(tt

ro

<f tr)

(\

(o

co

ccr

@ co

lS

.{l <lr

ci

q\

'J>

rc-

aYl

s

fD

c)

tl:)

rq

<:

L')

@

Ho\

\O

h.

!O

o:

10

Hd

'..\

n

N

(tr@

OrO

it)

t.J <t

o\

(.c@

*td

ir)

Ch

ir^)

\C

Or

(.().:

lri

Fi

FI

l:l

11l

tt

li

lll

l.

F;

FI

l;l

l=l

tl

hl

t'l

ll

tl

tsi

tl

tl

tl

isi

ll

tl

l-l

i*i

H

rl

tt

isl

;<;

rl

rl

rl

r-l

iii

It

ll

tt

ti

rt

;

CO

('r

r:i

(U

g

,->

:t

g)

f,

o

L

t

+,

(r)

f\

o,

-)

P

.Y

c

l!

r:-

o

N

o)

-.Y

,U

-J

c

(U

q,

l+-

r{-

(J

o

|+-

o

q

F

o

D

c.

(J

L

E']

E

c

.P

'E

.tt

o

=

rJ)

\o

o

a

rU:

F

<J

<t

c)

.

N

(.o

Cv

frr

(\J

ta,

sf

CO

--l

(\J

d

\c

<t r-r)

st

(\J

Or

(od

\o

it

\o

O

rf)O

st

ca c'1

(o

(n

('r

r')

tJ)C)

tt)

g)

f,

|].

(n

10r\

co|f)

C!

e{

OJ

-1

@

rrt

rf,

N <r

\o

sr@

C\,

d

gr

<l

dJ

tr)

r)

ce

@l')

F{

r{

@

o

O!

F{

O

ctF{

|

cr)

.n

(r)

Or

Or

H

I

O1

r\

tt)

(\,

r\

<l

Cv

oa

trJ

oJ

co

cc}

i.c)

f'l |'r)

|\

Ol

Or

I

gJ

t\-

Or

I

e

frl

..

d

F\C)

rf

r')

<t

l

rt)

ro

€c'

(nl

,

\f,

Nr*,

.nl

6

'!l

(lr

C

Elco

oi

c

'F!

.J

|tt

col

o

.o

o

lo.r=

ot(Jt

(u!

slF

Ll

r

I

lLl

?-l

-O,D

tl

s:o.EcL

<l

to

o

'tt

d

o)

r/,

1 ooo

<l

E-JErro

tr)

tr)tn

o

c).{

e{

F{

F<

{Y)

F-{

(O

cf

t-@

--{

NJ

"{

ql

or

c

(o

c\J @sr

ol

\o

dsr

ql

ful

Fl

or

Nc\J

C\r(\,

Vll

d

?-{

@o

H

(,l

rOl

H

o

t'.*or

El

u1

.nl

v1

El

6

ol

ct'ic'llqtcol

src

.elsOElsO'Ftco

6l

Col

CcolC

le+JtO.el-.!r,Olr.J.g

+r!

c'd(uCOI

c),tt(U.rl

(3^,(U

-c!

o

!,

=

|

o

rt

=

.cl

o

{J

:E

O{

()

tn

(ul (J

tr1

oI

L)

v\

'-l

+F

(|)l

st-

'rl

<t-

3l

olrrLlrrolrl

F{

E.o

tr.l

Fl

Pd

3!

-l

TltO

I

co.gct-

rl

Eogsr-

!

co-ccr,

>!

.uofttru(l,

sl

|Uo|!.Uo,

>!

tl

(uoo

>

utl

(uoo

>

L!

(uoo,^to,orrro

Ol

=-J=(YrO

<l EJ=ctO

ol

EJET,)O

i.,,

..

:.,1-.',.,:,;.,,,

.;..-.:...,.-.-.'.....:..-..,..,'

,

.

t

.

:.'.:';,'

-

t,

(c

iV

or

GJ

F\

@

Crl

ar)

t')

!n@

aa

aa rc,

F{

d

C\J

d4

-l

n\

st ctl

r{

e{

!Q

'F-d

-{o

a1

i{

Or

--l

Oh

f\l:

N

ri

HH

:l

---

I

t

T

I

I

I

T

t

t

T

I

.lutDlic-a_ligns

of zosilank-lg1_g.qlg

'

In

view

of

the

overa ll

purpose

of th

is

st.udy.

a two-year.

datd

srrt cor.ls ist ing

of

monthly

observations

of the

zooplankton

corrynunity

structur-c

durinq

a

periori

of

nater

management

improvernents

*as'not

total

ly

successful.

Cons iUering

that the

ideal

situation

would

have

incluried

a minim,.rm

of l-2

years

of

data

documentinq

the

lake's

decline

and its

low,

the

concept

of

a

2-3

_year

study during

the

itnprovement

phase

woulcl

have

siqnificant rnerit,

As

it

stdnds now,

it

is

diffi-

cult to

rJistinquish

cause-and-effect

of water

treatment

improvements,

per

se,

frorn

expected

differences

attributable

to

rratural

year-to-year

variability,

:

llowever,

despite

this

drawback,

it

i_s

judged

that

zooplankton

jjr.-c-oj.r:un

_Lg!.-g

*ruL94irq.-L9qkr9--ry9quq!.iyg-q!!l-.J-i$-!-eieryi!F_!!{ilc9t

!e1ps1'qtq1e

::ga_:lt

| :Il9l.l.:_3nj"

gL$

t]jl

!e

!

tr

ch

ern

I

s

!1r.

In

addition

to'the

monthly

collections

of

zooplankton

in

Coffeen

Lake,

efforts

were

directed

toward

several

specific

ecoloqical

questions

that relate

to

power

pIant

effects

on these

organisms.:

LTPIODORA

:

;,6.20

.l

Recent

environmental

studies

of

electric

power.coolinq

lakes

in

centrai

I

llinois

(l,aite

1979a,

lgTgb',1980)

indicated

a notable

paucity

of

the

cladoceran

zoo-

plankter,

Leptodora

(Fig.

6.1).

Because

this genus

has

been

colleclgd

(l)

in.

large

numbers frqn

other

non-cooling

lakes

in I I

linois

(Shelbyvi

I lefCarlyle,

and

Rend)

and

(2)

from

lakes

and

reservcrirs

in

the

northern

l.lnited

Stutur'(n.*

records

are being

reported

from

Kansas

(Prophet

l97B),

0klahoma

and Texas

i,,0,,

|g7g)J,itwashypothesizedthatenvironmentalconc|itionsspecificto.coo]inq

lakes'

were

detr:imental

for

leptodorid'biology.

That

!_gp!g!gl-e.

is

absent

from

a

lake

can be

significant,ecoiogically;

they

are, important

links in

food

web

dvnamics

Delween

prl.qg!:.Y"-endJg{iryJl$t:_P:lit.

l,lhen

presert

in

larse

densities,

they

constitute

an important

fraction

of the f.i:heriss.:-lqqd

hse

(costa

and

cummins

19721

and,

d-u{q_.tlglr.jrgdgr_o_1x-f-ps-d_lng_habits.-__t[ey

gqn

tfre:lgqls9l-11-.Pgynlg

ttll9!5-{g-9tll9jlj.lTs.

To

test

the

alrove

hypothesis,

dn

assessment

of,leptodorid

biology

consisting

of two,phases

was

,r,

t

j

T

:

I

I

I

.'::.r

'

-'to'

'.:1.:

.

I

=1:

I

, ::: :::

t,'

;:>-,

l.

l'

{r.:.!

.

l

uhdertakOn'.

---

lhonnlogour

to

clraprca

o( otlrrr

Chdoconf

lrood

.

chrmbct

r)vtry

Zad

.nt.an

c

lbiterrnurt

,

[thorrclc

bllkct'r

turrounrtioi

trrouth

rnrndibh

brrlr

Lcptodorr

!!1g!i

lFochol

Q

Fi9.

6.1.

Drawing

of Leptodora

kiddtii

(Focke)

(tat<en

from

costi

1967).

,:'t

6,21

:,,:

---

I

:'

-.

l.u

f

.:t

l-'

I.:

I.

-.

I.

I

I]

I.

:

I:

t',,

r,.

l:

I-

r.'

j.

f,

I.

I.

,,,

I':

l.:

!

l:,

I]:

I:

!,,.

l:.:

I

r'.

.:

r,:

I,'

r.:.

r.,

'l

First'

a

prellminory

sdttlrrling

rLrqi{fie

was

initiaIeiJ fo'l.J

!r!rc.-.,',vhich ret)rLr-

:'

sented the

basic

morpholo{!ical

types

in

ll

I inois:

cooling

laies,

f

loirr! ci,r'rl

ral

'

dnd

water

supply reservoirs,

recreational

lakes,

etc.

Ihe intcnt herc

was tr.

determine

whether the

paucity

of

lgglo{o|3

Hds restricted

to

cooting

Ialies,

r,

This f irst

phase

was

corrpleted

withi n a z-r{eek

periorJ

in Sr,ptr:mher

l9B0

when

populations

typical

ly

peak.

The

sampl

ing

progran

consisted

of

two to

tlrree

ver"tica|replicatetowsfrombottomtosurfacewithastdndarr|5:lconica]

plankton

net

dt

two

stations in

edch bdsin.

Ancillary

profiles

of dissolved

e

water

colurnn were also'Laken

dt each

:

stat ion.

Theresultsofthesarnplingwork(Table6.6)rJirJnotsUpr,ortourhypothesi5;

that is, Leptodora

was

found

only

in three

of nine

lakes

that cJo

not

receive

heated

di

scharge

waters. These

.{ata

jujg-qs.tg{.

lfg!,.-Iosed--an...the-.one^-.Ljrne

ruPliN--ef-tqrt

!-qr-sqX--sJs-dv--1-afs,-9.rl.y-ttgmel!g!-cgqr!i!ig-ns,.9far.99lelittig

oJ

9-991-1.n9-Ffgl

p-qf-fp--(lteat-regime,

phy,l.!.qil.

entrainment.,

gtc.)

ma.y

not

he the

l:l:-3:-THllLus*!!s-se-qsllggaoj

!-qg!odg3-in.

!lrq:q.

svstclls'

rhe

Quastion

was then

changed to:

what are the

conditions

in

both

coolinq

and

rron-cool inq

lakes that disfavor

leptodorid

production

and/or reproduction?

l

Phase Two consisted

of conrluctinq

an

extensive

literature

search

for

infornration"

concerning environmental requirements,

feeding

behavior,

and reproducLion

of

lgp.lgqgra.

Most authors

agree

that

certain

abiotic

factors

o1)r)ratirrq

in

aquat.ir:

systerns cornbine

to regulate

the development

dnd reproduction

of tq.p_t-o-O-.rtl

(Cummins

et

al. 1969). Two f actors that

rnay be rnost irnportanr

in

the biotogy

of

this

oroanisrn

are

water

ternperature

and

photoperiodism

(Costa

196/).

Ihe latter

is important in controlling

the

synchrony

of

the

lratchlng

of

winter

eggs

in

the"

'spring.

The

photoperiod,

may also

work synergistical

ly

wi th

a sudrJen drop in

,gater

ternperature

in

auturnn to

stirnulate the

production

0f

,

rnale

forrns

end,

rr'iti-

rnately,

sexual

ly-derived winter eggs.

::

-

.Intheoriginalhypothesisofthis.study(thatcoolinq.|akeconditionsdjs-

f

avor

leptodorid

Ot:Ou..t]:n):

it.

was

assurned the

at.ypical

ly high

water

ternperatures,

even

in timbient

waters, in Coffeen Lake

during

late

sumrner anrJ

early

autumn

prevented

the

production

of males. During

this

period

jn

other

,,l.akes

containing

Lgplgdgfq,

those

Bopulations''

r"each

their

peak.

llowever,

,1.',,

t

l

1,,'..

I.'::

f.'..

at:

1.,.

!',:,

:.':,::

I'

---

ii

4

E'F

:4

a*'

tt]

+a

LC

9..r

arF

i$

t-

o,s

c

Fa

o.r

l.)

OL

6_

'q€

.:.::'

.:

.-

,

'

.:

.

a

-

,,:,

t'.i

ilt'

'I'

=f--

.JC

t_=)

*

.{'

},.:

{'.

n,

i,r:

r::.

:i

€.

_

!>

c)

.J-l

.{

rl

ir ./; s-

a':-

C'

rj

,-

(\J

{\J

(\'

(\ H

a\J

(}.

+L

fl

n.

'j

I

l

l,t

I

I

t

i

r

,

,

j.

(}

Cl

**

rJ:

C.,fr

*.€:

\ (\;

ri.a

C!

1-

{c|CC.{

q\N.r

f.

\

e.

i\

i:

t! a\J

r! f\'

^1

t\,

A;

G*

i.:

rn

c\l f'--

rJ.)

€Gn

\()|n

O<>14-Cq;.<tfiCC\',r-

rL

OOrnr!,jOgit:.rOCC,=

i

I

I

r

|

.

|

. |

|

r:

r&_1

d

r{|

F.

ir:

r$

e,J

+

-j

Gj

F

{t\

rrl

\G

rD

r.o

Oi U'a O1

F-

ci

|{o

r*.

e,

r,.

s,.

OJ

I

c

t.

c

E

r-*'(J

4S

--

a

Lv

(l'

*2

,E

3

''l

t

r(}

dl

.o!

-

(tr

L'i

At-

.co

(u(J

Eo

tt

.,

r

La:

fa{,

€,(u

u

,t'

g!,

tEtg

,v

Li_

pl5ol

d

ol

l''

elE

arlq,

Jlu

(J

l'-

e.-

L(p

-

v,

It

o,

FA

O.

!t

t6

E3

yr

ol

(,01

(l)

.trl

Ll

r.ol

d +,

I

-el

(Ul

vt

Jl

o(u

gL

.

,Fa,

*s

F=

('}(l,

a

FIJ

.4

g*u

c'.F

€r/r

ttcu

,

V1'F

X

.F,

.0

Jl.-

io,

.(O

'

pa

Ar'

':

D'

E:

.*

''l

g:l

o)

iJ:

-

f*t

q

g?

.t

tJ")

.ra

g"

ftl.

<}{}€.OEFi

+

{tOA.<<3rnC.!q

(if}(i

.!

C

d(\lit

rlcv€

vi.t

10.f

c-

\o

E

CL

CL

q,

c

Cii

)1

t

j

El

;

cri

oi

i

I

I

i

;

t

EI

1

t

{

t

I

I

I

I

I

(ul

+rl

|lti

-i

"r0

ot

a

c

E

o

tt

TJ

(J

o,

tf,

g

!,

[a

el

cn

c

o.

E

|l5

:e

I

iu

iH

fL

f

!c

lo

ls

'l

il

',i

:

:i,

-l

t,I

,l

il

/t

:+,.

rI

c)Qc>c'crc>Ac}alc,Cc)c'

@QCOCOofSttisst&€tEt4'

\

\

\\

\

a..

\.!.-

\.

"\

\'i

\

!oQ0€q\q('|C)"1

dav\d\O

oc)c)o()()ciGcl()c=€5

\\\\-\'\\\\\\\\\-\\.

OOOc.O()dH.{ddHF

o

o

q\

or ch

0t or <'r o,

or o,

or

o\

.oJ

Jtd

C*i

+-<

(r*

O

s

J

qrt

V,

{-{-.!F-;4J4t*

LorLe+--a$

qroroirJ)

.EJ=-@LJ

q.J4ErUl&JQJ-J-JJr3F(r4'.J.FJo|,!tt

z.yrJ>\4t,EtC

l:

E _ !l

LJ

-y

o

(lJ

'ug(uo

go4rtrcce-c

tz1

OO>

c

Ot*J'-,-

1 tvt

.)

O.C

>

4'

t

(u.q)

a,C(u(u€O,-EU1llrp.-0J

.x,e8

tF

e

t6

J

4

Qt

I

ar

(u

r.!!

L

{!rrr

C

t:Frts

.o

<}'!

Q.ll'

{

J(JJJZUl(JtrVro(JcDJ

l,

:'

I

J

u

,tt

J

6.23

---

a::a':::it

::,:::::

.].:

..:::

.:

:

)-,.1

:

T

I

I

I

I

I

T

T

T

I

t

I

t

I

T

I

I

I

I

'::

'

,:

.1

.

Leolodor_q

cin

rdre

i-r

!ury

r

vr..

charges 0f 30'C

dnd dbsYe

rt

ent

ire

Fopu

!

at

ion

bef*rp

rpEl

H,f lSf

f.r$pfr5!,1r;;r,

a,l..t;;1t

.''i'

.

:'1,,1t;,,;

iii

n

ri:i-

d}t{eert

;3i(r3 f,ur:;r-T

:4iri

',,J1t1i,'r

r':.;.=':.1

+t'-:rrtt'::t

'1-ari,:

iq6;

3r #!lltrrr'

{-}C{i.,

t.':.;'.1

1.,r,

"'\t\'

i.1.

,F'.1i.

Ttre'f;Ct

that

!B!!q!lgg!

rf id

not

nFpedr

ro

{rr'{.r

nal{ .;! !-ti{i

f!{:==iiril irr'r

i.li:*q

t,n{,

litq,-'1!

'ff

aai

iur*

*1.

thesd,.organit[E

ril.hisr

the

bloti{-ahiotic

!Lrur-Lurr:

g{

!dtF,,ysf{:tl.;.

ln

totn-,

narv, H!!L.rAl-.,ortSlI.E"!1y..

ltrquglt

to

be

an dncmriy

in

the

rlce

urrcnce

of

tgp-to,-

!|-org

difggtl,t,

-t:-n-teg-la-.g.g9.!l!g

lqhg

{or'ditions

il

nor

consrderec

a

much

qxrrr

co|:q'!-qL-

phenornenon

rhtch

over

laps

iianJ

dif

f

erenl

lypef

of

a0uai

iq

qr.{).,ysir^'ns.

B05l,ll

liA

,

Res0'lts

of

both

Year

I and

Year

7.

studres

of

foffepn Lake

ghored

dn

unssually.,,

lo*ioccurrence of

a

small-trodied cladoceran,

!g;ggl;

these

tlenrls

were

ir,"er-

preted

as significant

in light

of,rntir

occurrenee

in

0lher

lateq.

Quest!on::'.:.

0o cooling

lake

characterrgtrcs,

suclr

as

increased

temnerdtures and

entralnrnent.

reslrict

lgJrnUg

prorJuct

ion?

One.,possibi

lity

is,"that

temperalure and

entrainmEnt

indeerJ

oc./!rn

th0 dyna;pitg.

,

of

bosminid

populat

ions,

but

probahly

at a

cnrynu4i

ty

level. llowever. i

n L ak+

S.rngchrls,

Bosmlna

occuffed

lakenide for nearly tlre entire

year-

{tJaite

l979ai.

One

other

possibitity

is

that

some

water

chemtstr.y

parameter

limiled

their

production

in

eoffeerr

l.ake.

The

pH

rdnqe

in

Coffnen

Lake

was

similar

Lo

[hat at

Lake

Sangchr

is

and

{.!-r:olved

oxygeo

.levets

nere,,wel

l aboye

fhoser.require..{

-fqi-,:

t-g.Lt_?-o-_o1llA*lqfs.:

UnusuaIty

hiqh

levels

of

tota]

dissolved

sq]ids,

chlorides.,

mO l,

iirtut'

iS..t

ion 3)

rnly

indeed

have

an

irnpact

on

zoop

I

ank t on

b

io

log,y, hut

tolerance

lcvels

are

not

wel

I-documenterl

in

the

I iterature.

A

iecond

hypothesls

night

be statcd

as

follows:

bosminrdt

in

eoffeen

Llke

ar.e

sub.tect

f u

heavy'predatory

pressure

by both'vertetlrates

{f

ish}'anel

invertelir'ates

6.?,4

---

:,,,

-.

"l=

I

i-

I',

.-

*

r:i.:

ii'l-

;1'

i

',,

,.'-

il

i.,1,

ar:

:::

i'I,,

!,,.

"tt':,

lif,

i.,1i

-.'

i,Jt

i'l

i,,t='t,

tl,

;', , :,,.,

i'I.

ti,

,

..:,,,

tI

rf

iilggbgr{:

trrrd

{;vc:?*pr:i:1

lr:g:=grr.:gr.;.

i;.133r;

,.;*:

, il='..,*.:

::;:;1;4.r-.,r...*

!ri<i

-.

{=r:i.:i.;

r;f

veftefirate

predat{l11

li'i4,s

!

1

lt,rtiolri

,-

1r\;6.,-'nrlr rr..

:.,,...,..1

.1..r

1..1

... -

,

..

,

...t

larger

hslrhirerf

s.

?nel r*i-]t

i...t1=r

'll*

=t

7',11+-t:

*=,)

.

:i;=,lti,:

1,1

;.=:.i;;

l;rri

!r-r.i= ln

biuegi

ll

rtcarchs

:q

ftf

f

cen L*iF'iireiri:-rri

ii:

:;:;*{t5i

ix+r

'?t:i:

2r?i}:.:r:.r

f

3:iii;r

mdy

bC

in(rftd1ed

f.{jrfrDf

t

t

l

i6ri

f

r;7

f

la:i*t

i|r

:..y,;,

.

\.

4t

t;

it,,.

.!

4l

:r

..

.

Iherafore'

it

is

tulptr{+.+d

lhrt ltr:

:nfi.tq-trr

:,-.,,rrr++ttt :.:l

iictnrne :n

l+,f

feei

Lake-ras tlot

dit'of

t

!y

reloteC

tc

lit).t.

t

tttl

4r.;

pf

{*r1

?s,

liiit

't

-*'*-;

F,-Dbifriy

th*

result

of

heavy

pre6Sur€

by

!nv*rr,t!:rdr-F

!if.fJa?,.r.

il :..r

6.

i,.

ttt tRA

I

r{f,rtr{

I titt IHcll0r

06

I

r-s

Asidg

f

ron

t.he

pntentiai

ohyt:r),!c,:i.,1

!

,.f

fe{

!..

ri,

"4..,1

r.

}rn.rt

;n

dcrJ,:i !r

t:,r}t

I

:n

the r*cervtng

sy:text5 {townltrettr

ir{

ir't*r,r ;}!6nr.,

,

ririt.

:-),t

!t31.

n.-.,1

ri:in.ir!;ll

i:e.r-

IUrbdtiOnS

tO

the$e

Syitefns it

lire

t.gr!,;1

rn74

rf

f

p;

r..,

+l hl:e:

r,tn

tfrn

3rhy5ir.,tl

f

OrCtS

resrrlting

f

ry1

entrainmgnt

thri;ql11., tnf,

1,t4r

t

;;r.r;plr-.

ilr;.0rirr tfr{,

,ritq,

I

Obvious

ef

f

ects xefa initiai.ly

d9s,rc

teled

;rtrr

f

i,,h

{r-.:tlt,i !

rnn,

nrui:h

i:{

!+e

cntrllntnent *cJrk

has

br:en direr:tr-ii

torarrj

1:r.:rfeliir

,:nc

fr.,rr

g+nrpi:rrq

'rrrllh$d*1.

:

oqlgs.

lt

is

also

lsi'J.red. hor{Fvqrr,

thal.

$!lr.i: tifri,,

irlrt

!itn:.ti!r lfly,}rtehrdt+1

ar,l affeeted

lry

{?nIr0in'llent.

hi;t

,nrrUrodr:!fr.Jri,5

hiyrr

'f;

!r,ir]

cds..,5

,rrel

I

utltr!

.tn

dCLifrdte

rlelrlrrninat

iOn

rlf

||n?'tdlr!.y

rg1q,.,.

ftt|t

,t!

thf

,rh.,icrr"!

1yr,,,

,1{

ih,t

c*i}-

project

iraE

to

atSless

trio

techntqires

:n

t{,rr":!

,.;1

..trFt"

.,tr,;lltcily

.1rrg

r'r,itlllr

l-

ity'for meas:rrinq

:oopl.inirton

enira

inr.'s$t

!s!hoi--q!g

Ihe f irsI

rnetltort

terLed

iln$

AIP

iadcnoitnp lrit,hri!Fh;.!ti]

],\.ty.

lhr.

de!r,rir.!

rra-

tlon

0f

llve

biomass

in

dqudtrc

erotycir3inS

has

ilri{:ri

fr"rrr,tr.Jler!

lly

thri

frrr\f.rrfi.:

of

non-l

iving,

particulate

rdetrrtus.

6ravimplrri

lechnler:e.,

iwhri;tr

gsrlr

utifli zed

in

the

biornasr,

determinalions

drseuires

€a.'!ir.]

s.,: oiten

suitable

when total

orfdn'ic cont€nt

is

reqrrired,

hut

rr:

unre!.!ohl*

for

d€tsr{ninations-+f

I lve

bfomass since

totat

lnass

contains

lon-

lirinq

or{ldnic

e

onEtituenfs

{L;nbr,r.

ll,

1973). ATP

aSSay

ian

be

An

idedl

methorJ fOr

live

broftl,s(,

pc.tlfirct{i.,

hec;uge

it

is

found

only

in

livlrtg.

celfs

and'ls dstectable

eyon in very

s+ali

irmunls.

A.?p

ls

Crtracted'in

a

'bol

ling

Tris

sOlution

and

rnjee

te4

int.o

+

lucifari-n-lr,rcif

ertse

---

l-

l.=

l'

ooo

'\

OOcoc

T=

l'

l-

t:

l'

!:;;r:

tt'

-:.

l-

r

r

I

l.

l_.-__*

I

Rel

a

ti ve

S'! ze

of

F----

.---"-.-;'

:-*---.-;f

Bosmi

na

Zoopl

a nk

ters

T

Flgure

6.2

Influence

of vertebrate

(flsh)

and

invertebrate

rrredators

on

ioo-

plankton

prey

populations.

Lack

of vertebrate

p"e,riiori-rouoi"io

1!rong

lnvertebrate

predition

and dominance

or'larrJer

ttu.riiun"oi"

The

reverse

leads

to dominance

of

smaller

herbivoris.

irte

forner

slIudIron

supports

the

proposed

hypg!betis

r:eqarding

qo_snrina

in

.:,.'

',

,.

'

Cof

f een,

Lake

(deri

ved f r'onr'

stensohl

t ele

;

.

:'

: :l

---

I

-i:

-a

I,:.

I:.i:

t,l.li,

,

I::

I.::

r..

-:

.:

-:

I:.

I.',,

1,,,

I:,',

1,,'

a::

:

I:

r:.

::::: ::

I:.:,'

io.'

!.,t,

:j:=.'

'.ji::'.:.:,:,.

[1*

(f

iref ly)

prepardtion,

where,

f

or

t'each

$ulpcillt

of

AIp

hy<!rr:lylrlr'!,

r.n'r

;lhr,1ton

of

light

is

emitted.

The

concentration

of

AfP

rn,J

r,rrnpi,]

rAn lhr,n he cnlc'rldteC

by.measuring

the intensity of

I

ight

.rith

an

,1,Ii:

pnotcinpr.er'.

fJrt.ai ]cr:

rci hods'

are dpscribed

by Patterson

,et

al.

{1970),

t{olni-l'ian5en

(19??i,

lreb[,r

i:9?3i,

'APHA

et.ral.

(1975)

and

other.,.

,'

The

proposed

use

of

the

firef

ly

0ssay

i<Jcally irould

lre

two-folrJ:

(l)

ts

rtevelop

a

method

that

closely

estimates the

degree

of enIrainment

rnortality

in

Lhe

discharge

or

other

reqions

of

the

receiving

systems,

and

(?)

t.o

rJetermino

overall

viable

biomass

fractions

of

the

standing crop

anywhere

in

Lhe

system.

The

scope'of work

for

this

rnethorjology,

which Has

teiled

clurinq

August

t9i9,

included

the fol

lowing

points.

fiepl icate

samples

of

plankton

were

col

lected'

from

both

the

intake

and

discharqe

canals with a

t{aile-0'6rarty filter

pump

(wtrictr

yields

Iow

sampler-induced

m0rtalities).

Sarnple

tirngs

yg,'s

varied so

that measurements

could

be'made

durinq

periodt

of

pumped

discharge

under tnthi,'

heated

and non-

heated

cond'itions.

In

this

way, measurements

could

lrc

marre

:

during

different

phases

of'the

plant's

operation to

dssess

s6rnponent

stress

:

parameters

(i.e.,

temperature,

mechdnierl

abrasion

and shearjng

forces).

The

final

data

could be interpretec!

hy

developing an

index in

which the

percent.

survivor.ship

would be

expressed as

the

raiio

of

ATP-discharqe

to'/rTP-intake

t

irnes l00.

After thre*:

daylight

collections'w€re

taken, the

rtata

were

founrl'to

be

extrernely

variable"and

non-repeti tive, so sampl

ing

was disconLinued.

'

fhe

'dutu

**,'e

invalid to the cxtent

that they

will not be reported here. ATP

extracted

from

.

paired

intoke

anrt non-heated

discharge sampIes was, bowever,

rnore

consistent."

than those

pairings

involving

heated

discharges.

ln the

lat-Ler.case, both

AIp

per

unit

volurp of water

and

ATP:per

unit

biomarr were

gr^eat.er in

the discharge.

These results

,led

us:

to

con:iider,,some

other

conditions

and +ssumptions.

One

inportant

assumpfion

of

the

ATP

assay

is that

concentrations

of

ATPlcell

remain

constant

from

one

individual

to anotlrur, ds

well

as

amonq species.

I

I

6.27

---

-..,--.

I.

I::

l

.:

-,.

I'

r-l

I,.

Iheoret

ica

I

ly,

however

!

a

relat

ionsh ip

frel'eren

AiP

aErrl b

io*Jrr,

t,:n

lrp

{rJfrs

iderrid

vdtid

only

if

physical

parameteri

af

f

ectrnU

metdb0

lrr-

rat4g

{

i.r:.,

iilii,ytr

it.r,'f:r

sd

I In

i

ty, etc.

)

are

cons

idered.

l.

T

l''

I

T

T

t

I"

l=

t

t

.

.:...:

T

l'

,

l''

..4:

l=

l=

"

l,=

:

t

,:=:,

---

,l

a;

:.

'l

'f

.,1

,l-

.l'

:,,,

j

::

.

il-

'l

Zoop'lankters

Here

col lected

from

both'

t.he

inlake

,aorl

4ischarge

regions

(representing

ambient

,rnrJ

heated waters) with

a

f

i

lter-purnp

appdratus

(l,laite

and

0tGrady l9B0),

which is known

to reduce

sanpl

ing- induced

nnrta

I

iLy.

The

or'ganisms-r{ere rinsed

(with

lake water) rnto

d

smdll

sieve,,

which:

was

'inynersed

in

an

aniline

blue dye

sollution

(5

g

aniline blue.l00 m1-1 rti:tiller!'

:

water). At

the

end

of

a l5-minute

irmersion

period,

Lhe sieves

willr

organisms

were

removed from

the

dye,

rinsed,

and

srlbmerged

into

hot water.

The

"heat-

killed" specimens

were then

transferred

to bottles

containing

l0I

formalin.

Optimum

temperature for

"heat

kill

ing"

was

50'C.

Temperatures

above

this level

yielded

partially

stained

indjviduals

and

i5

to 90'C temperatures

resulted

in

a

total

denaturization

of

proteint

,tru,

no

rJist

inction

between

l

ive

and

dead

organisms would be

possible.

.

Virtually

all

samples collected adjacent

to the

intake

screens cont.ained

entire-

ly unstained individuals;

these

result.s, irr

arJtJition

to

laboratory

tesLing,

indicate

no

immediate

effects

in

consuming

[he

dye.

0ften the

organisms

had the

dye

particles

in

part

or all

of their

guts.

Although

sonB

organisms

sampled

from the

rtischarge

reqiorts

were

partially

stainerl

(inrticatinrt

a

nossible

mori-

bunr!

conrJition),

most

were

either

whol

ly stainerl

or

unstained.

As

expected,

large-bodied cladocerans, copepods and

even

rotifers rver€

5[3in96,

intJicatincr

their

greater

susceptibi lity

to

entrainment mortality. Prelimindry

calculating

o-l-.1lleg4g[L,..p-]u-s*t.g!1pJgI

IofFl!-t1.

i-ndqcated

that r.*e.

than l.0X

of the

returning

:--J*'-

organisp.s-3ere

dead.

The

fact

that these

orqanisms have

short

repro-

ductive

cycles

faci

litales

tlte

recovery'of

their

popu

lation

rrumbers,in

down-

stream

waters.

These

clata

are

similar to the

estirnate

obtained

for

Lake

Sangchris

(|,laite

1979a)

.

0f

the

two methods

examined

here', tlre

dye technique

was far

superioi

in

terms

of

simplicity

of

both field

and laboratory

procedures.

Since

several

larval

fish

collected

with

the

zooplankton

were

,also

dyed,

this

methort,

with

rnorJif

icaitons,

maybea|soeffectivefortnort.1|itystrrdiesoflarvaIfish,

FI

il

::::

.

::.

:.:

. :: .:4,

6:29

---

.

.

:

LI

IEHATURI

CI

TTD

Ahlstrgm,

E.. H. 1940,

A revision

of

the

rotatarian

generd

!1.r!hjg-tg_1

,rn,J

PJ

atvi.qs

wi

th descr

ipt

ions

of one neil

spec

i

es

anrl two

nFJlar:i

dt

ies

,

Bu I

I

.

Amer. I{us.

t{at.

Hist.

77:143-184.

:

,

:

. 1943'.

A revision

of

the rotatarian

genus

Keratella

with

rJescriptions

of

three

new

speces and

f

ive

new varieties.

BulTl6Erl-Hus.

fiat. itist.

80:4ll-457

American'Publ

ic

Health

Associati'on,'

American

lJater

l{orks

Association,

and

lrlater,

Pol

lution

Control Federation.

1976.

Standard

methods

for

the

examination

of

water

and^wastewater,

l4th

ed.

American

Public

llealth

Association,

l{ash

i

ngton,

0.

C.

Brooks,

J.

L. 1957,

Systematics

of North

Anerican

DaphUl_a_.

Mem.

Connecticut

Acad. Arts

Sci. I3:1-180.

1959.

Cladocera,

pp.58/-656.

In l{.

T.

Edmondson,

ed.

Ward

and

.

llhipple's

Freshwater

biology,

,Znd

eil Jotrn

l{i

ley and

Sons,

In'c., New

York.

Buckler,

J.

L. lglg. Benthic

studies

of

Coffeen Lake.,

In Environmental

studies of Coffeen l..ake. First

annual report to CenTFal

tllinois

Public

.

Service Conrpany

by

lllinois

Natur.al

History

Survey,

Urbana,,

Il'linois.

Chengalath,'R.

-Syl

1977.

A list

of Rotifera

recorded from Canada

with

synonyms.

logeus Series, No.

ll,

Canadi'an

Aquatic Identification

Center,.

Hai. Mus.

Natur., Sc,i.,

0ttawa.

.

'

,,

Costa, R. R

, 1967.

Population

dynamics and ecolooy of Leptodora kinrJti i

(Fo.cke).Ph.D.dissertation,tJniv.ofPittsburgh.7T9-i.r,.-..

Costa,

R.

R.,

dnd'K.

Itl.

Cummins

,

1972. The

contribution of ,Leptodora and

other

zooplanktontothedietofvariousfish.Am.Midl.Nat.T7r2T559-564.

Cumnins,

K.

tJ.,

R. R. Costa,

R.

E.

Rowe,

G.A.Moshiri,

R. M. Scanlon,

and

R. K.

Zajdel.

1959, Ecological

.energetics

of

a

natural

population

of

the

,

l

'

predaceorrs

zooplankter,

Leptodora kindti

i

(Focke)

(Cladocera).

0ikos

20

189-223.

Edmondson, 1,1. T.

1959.

Rotifera,

pp,

420-494. Il t.l.

T.

Edmondson,

ed.

and,tJhipplels

Freshwater Eiology,

Znd

ed. Jolin

I'li

ley and Sons, lnc.,

York.

Goulden,'

C. E.

1968. The. systematics

and evolution

of

the Moinidae.

frans.

Am.

Philos.

Soc. 58(6):l-101.

Grothe,

D. H.,

and

D.

R.

Grothe. 1977. An illustrated key to

thc

planktonic

.RegionV,CentralRegionalLaboratory,Chicago,IL.::

16tifers

of the

Laurentian

Grreat

Lakes,

U.5.

Environ. Protect.. Agency,

t

I

:

I

l'-

!.

l'.

I.

!':

I

I

I

t

.l

.

t

I

l'

l'',t

r..::

Ii:;::

,

'.=.;

l,

tllard

New

:

a:a..:

:.:l

6.30

---

llolm-Hanse0,.0.

l!7?',

0etermination of

mrcrol:ial

nur,{rer"s

and

hiornass.

l3

Y,

l, Sorokin and'll.'

Kadota,

eds.

l-echniqurs

f,or;

thc'assessnertt

of

rnicrob

ja

l

product

i

on

and

rJecompos

i

t

i

on

in f retltwaterr

, IFP

Procrarn

!lo.

?3

.

Blackrel

I Scientific

Publ., Or.ford.

Ho'lt,

J,

R., 0. S. tlhlte,

anrJ

A.

P.

Covitch. i9iB.

0iscovr:rv

of

!-cjlggql'd

Urrdllj

(Focke)

(Crustacea:ClarJoccra)

in

0klaharna

,rnd Texas,

Southxest.

ffif. m(4):686-6s8.

Patterson,

J. H.,

P.

L. Brezonik,

anrJ

ll,

D.

Putnam.

19i0.

Measrtrement and

significance of

adenosine

triohosphate

in activated

sludge.

Inviron.

5ci.'

Iechnol.

a(7)t569-575.

Pennak,

R.

fJ.

l9iB. Freshwater Invertebrates of

the United States,

2nd

ed.

John lli

ley

and Sons, Inc.,

f{ew York.

::

,

Prophet,

C.

H. 1978. Occurrence

of

Lgltodolg

!1_01tlf

(Focke) (Crustacea:

Cladocera) in Kansas:

d new

recoid-l$'ilth*d?C-Tat.

23( I

):

l68-170.

Seepersad, 8.,

and

R; l{.

Crippen.

1978.

Use of ani

line blue for distinquishing

between

live

and

dead freshwater

zooplankton.

J.

F

ish,

Res.

Board

Can,

35: 1363-1356.

Smirnov, N. N.

Lg74.

Fauna

of

the

USSR

(Crustacea:

Chydoridae).

Acad, 5ci.

USSR.

New

Ser"ies

No.

l0l,

vol.

1

(2), (Trans

lated

fronr Russian),

lsrael

Program

of

Scientif

ic

Translati.rns,

Jerusalern,

Stenson, J.

A. 1g76,

Significance of

predator

influence

on

cornposition

of

Bosmina spp.

populations.

Limnol. 0ceanogr, 2l{6):814-821.

l,laite, S. l,J.

1979a. Zooplankton

dynomics of

Laka Sangchris

ancJ

Lake

Shelby-

ville.

In,tvaluation

of

a

cooling

lake

I'ishery,

vol.

lV.

Final report

of

the

tllif is Natural

History Survey to

the

Electr.ic

Power

Research

Insti-'

tute,

Palo.Alto,, C4,

',

.

19/9b. Zooplankton of

Coffeen

t.ake.

In J.

A.

Tranquj

I t

i

and

R.

t.l.

-._larimore,

eds.'

Environmental

studies

of

T6'f

f

een,Lake,

Section 6. First

annual

report

from

Illinois

Natural llistory

Survey to

Central

Illinois

Public

Service Company,

27

pp.

,

and

S.0'Grady.

19B0.

Description

of

a,new

suhrnersible filter-pump

-uppuratusforsamplingzooplankton.Hydrobio1ogia74:lB7-l9l.

l{eber,

C.

l.1973.

Recent developnents

in the

meastrrement

of

the

response

of

plankton

and

periphyton

to changes

in their

environment,

pp,

l19-138. In,

b.

etass,

Cd,

,tlibaisay

techniques

and environmental chemistry.

Ann Ar6dr

Sc i

ence

Pub

l:i

shers,

I

nc .

,

Ann

Arbor.

'

,

bJi

lhm,

J. 1., and

T.

C.

Dorris. 1968.

Biological

pararneters

for

water

quality

iriterii.'

t,tt:

Bioscience

lB: 477-48L.

t{i

lson,

i,l. S. 1959;:'

'

Free-l iving

Copepoda:

Calanoida,

pp.:

]TBB-794.

ln

W T.

'

Edmondson,

ed.r,,'l{ard

and

Whipple's

Freshwater:

Bjology, 2nd ed.

J6hrr I'Ji'tey.

6. 3l

---

-_J-_anq-1.

C. Yeatman.

1959.

Free-llving

Copepocla:

llarpacticoida,

pp.

Bl5-861.

l{

tJ,

T.

Edmondson,

ed,

llard

and

tihippie's

Freshrater

Biology,

Znd

ed.

J6fi'n t{i

ley

and

Sons, Inc.,

r{ew

york.

'Yeatman,',H..

c. 1959.

Free.livlng

copepoda:

cyclopoida,

pp.

/gF-s15.

In'u,

T,

1.,

and Son

s, I

nc .

,

l{ew

York

.

.

l,

l'

l'

..:

T

I

I

:

l'

I

t

t

i..

l'

:::.:l

.

.'.,

''

a;

't

'',ij

I

l:

I.

I.

I]

I

6.3?

---

j::

'a,.

t:.:-.

a'

,

.

Sf"CIiOt{

i

,

BENIUIC

lFiVtST

l64TI0l{5

AI eOrrt-[i{

Lirrii

by,

Gary

L,

l.larren"

and'

.lamr)s'H.

Buck ]er

ABS TRAC I

.,

j

:

Eighteen

Uenttric

col'lections

were

rnade

at

Coifee,r

Lake during

Lhe

study':perio,J

in

order

to

ascertain

the

effects

of

new wasLewater

Lreatnerit

fo.l

lities'onO u,o

h{:ated

discharge

upon

the

macroinvertebrate

..

cornmunity.

l4ean

total

densiLy,

I

i

orna s s-

and

.

g.UlLail-TJ-J

ol-!.uqlguc

.

grgups

.]vere.

si

m iJ

ar

.Lq

t

ho

s e

o f. La ke

s

Sangchris

r----*!;

_;j_*__^-+.-*--

and

Shelbyville_,_

Il ljtois,

howevcr,

all

ilrree

lakes are

relatively

tlnproduct

i

ve when

compare<J

to

many

othcr

I akes

in

llorLh

Aner

ica

and LhrouglrouL

the

wor"l d.

qre*h!U.qf9_g-j-lg-J.g.!

-L99tq_i1ly-gf:tebrate

raxa

were

coil

tecLed

f rorn

::

Coffeen

Lake;

three

major

taxonomic groups,

0l igochaeLa,

Chir.0nornitlac,

anrl

Chaoboridae,

dorninated

the

lake

in

total

ahunrJancc.

The

se

same

gr-oulls,,dlong

with

Epherneroptera,

dorninatecl

toLal

lliomass.

l)oqrinant

ol

igoctractes

inclu,lerl-

unjdentifiedimrnatures,Najdidae,Dero<|igitatq,Aulodrilu:pigjleji,antl

Paranais

f ric

j;

domin,rnt

ctrironomirrs

were:

JSUE11

,

lgglglanvp!:,

[blyperji

lurn,

Cryptochironomus,

and

l)rocladius.

The lone

dorninanL

cha0b0ricl

w,rs

Chaoborus

punctipennis.

Station

I was the

sampling

location

nearest

fhe heated

dischar-qe,

an,l

nis

ooun-

whelrningly

predominat'ed

by

the

ol

igochaete

taxa

listecl

atjove;r

pr.ed.ltory

rnidges

were

also

dominant

at this

location.

t'ligh

ternpcraturqs

'ald

low

ctissolverl

oxygen

Een"a-errLruU9.n:4filg*i!9--.t-tgreLJgrUlu,-9:rs.Luderi,rnany,taxa

fnorn

ilrq

gi!g!e[ge

..

d-t:ea.

The

Statjon

2 cotnrnunity

was dominaled

hy q.

lrulc'L'ipennis

ancl

consistenly

had the

lowest biomasses,,densities',

and nurnbers

of taxa

of al

I

staliorrs

throughout.thestudy.T|'9-.gI!e]9.]-YLEofun.r|a.l.,.zonc-.31ql.'q.u1n11e'l.-!I-q'ryqa.!.:

stratif

ication

preventecl

cti1e1-1ijt

1!

:l.t:y:.,?

rr91y

fre119-

sreater,,

The

qn'mnu-nTffel-e!-sfatfons-3-ilcl

/l"ilei;

tdominated'by

chirononrictae

anrJ

wer:c

typicat

---

I t{IRoi)uc r

t0H

Benthic

macroinvertebrate

comrnunities,

rlue

to

their

trophic

position,

dre dn

important

component

of freshwater

gc6sys!gms.

Ihe

rJensities,

biornasses,

and

taxonomic

compositions

of such

communities

are

determinecl

by

abiotic

and

bioLic

factors

imirosed

within

the

ecosystem;

therefors,

Lhsse

complexes of

organisms

are

indicative

of

the

conditions

that

have

prevailed,Juring

their

development

and

aid

in

the

assessment

of

the

water

quality

and

biological

condition

of

lakes

and

streams.

The

llenthic

investigation

at Coffeen

Lake has

been

conducterl

as a

part

of the

program

to evaluate

the

operational

effects

of

CIP's

Coffeen

power

Stalion.

The

specific

objectives

of

the

benthos

program

were:

(1)

to rJctermine

if

ilte

quality

of

the benthic

commurlity

irnproved

as

a result

of

refinements

in

wastewater

treatrnent

methods,

(2)

to

evaluate

the

effect

of

waste

heat

discharge

upon the

bentlric

comtnunity,

and

(3)

to

compare the

benthos

of Coffeen

Lake

to

that

of

two

other central

lllinois

impounttments,

Lakes Sangchris

and

Shelbyville.

.

:.:ja

,t:'r:

li

l',

f,

l.'

i:

l''

t

I

I

I

I

l,'

l'

I

t

l'

I,

:

:

t:ii

.=

li

,,,tj

l.

7.2

l.

---

,l-

:--

rl-

i,

,,:

,

|4ETHOSS

Alt0 !'lATtelALS

,,

.t

,

Elghteen

benthos

collections

were

obtained

from

Coffeen

Lake

tJurirrg

Llre

\tudy

period

(September

and Novernber-,

lgZB;

Jdnuary,

14arch,

Mdy,

rr;;,;'r,-OrU"ri,

september,

and

llovember,

l9/9;

January,

Morch,

l,ray,

June,

Jury, Augrst,

September,

and liovernber,

lgB0).

Each

col laction

consistert

of

40

samples;

two

rep'licate grabs

were

taken

at.each

of five

sampling

sites

along transects

at

stations,l,

2,

3, and

4

(Fig.

l.z).

samples

were

obtained

with

a

petite

ponar

dredge(surfaceareasampler|=0.o24n2|,washedinaU.S.StanrJarr|l{o'30

sieve

bucket,

and

preserved

with

l0X

formalin.

ln

the

laboratory

each sample

was

examined

separately

under

a

stereorJissecting

microscope

with

magnification

to 40X.

0rganisms

were

hand-picked'from

<Jetritus

and inorganic

mater-ial,

identified

to

the

lowest

positive

taxonomjc

le'vel utilizing

ilre

Iiterature

in

Appendi

x A7.1,

counted,

anrt

wet-weighed.

'

Raw rJata

were

.onuurted

to

numller

or."

milligramsoforganismspersqUaremeter;...

,

i

''

:

0rganisms

that

required

sl

ide-mounting

for

identification,

such

as

Chironomidae

and

0ligochaeta,

were

cl-barecl in

10%

KOH

solution

or Anman's

lactophenol

and

'Hydramount.

Identifications

were

then

nrade

using

a compound

microscope

with rnagnification

to

.|000X.

Anci I

lary

Ineasuretnents

taken

concurrently

with

benthic

col

lections

inclurJed

bottom

depth

ancl temperature

and

rJissolved

oxygen

just

above

bottom.

Measurements

taken

during,collections

from

July

l9B0

through

Novernber-

lgB0

are'

i

nc

I uded

'in

Append

i

x

A7 ,2,

,t

.'

l''

a'-:-:

::

---

T.

:j.:':::.Rts'jL;5At{c0I5CU55I{.l,i...

ln order to

e;tatnine

the

benthos

of

Cof

feen

LdkD

in

pr.rspect

ir,,],

deta dcsii-'iblng

the

benthic

cormunities

of two

otlrer

central

lllinots

irnptr,.in,t'nrnt.s,

r.,lkc5

Sangchni

s

and Shel

byv

i I

1e, are

;lresented

for

cornpar.at

i

ve

purposr:s

.

Ilt:

rth

l..tkrl

Sangchris

and Lake,,Shelbyvi'lle

orq.newer anci

larger

than

Coi'feen i.otle, but

are

simi

lar

in

many

key

morphometric

character istics

{

Tarrle

7, I

).

LJ,.e Sangchrig

was

created

between

1964

arrd

1966

as a source

of

cool

inq

watt:r f

or

()lnmoriwealtrr

Edison

Companyrs

coal-fired

Kirrcaid

Station.

'The

loke

is

supplicd by a

1ow-

ortlt.lr

iIroo,n

(Clear

Creeki and

has,extensive

littor,il

are,ls.

Lake thelbyville

w.ls

colnpleted in 1970

by

danuning

the

Kaskaskia

River,

The

prirnary

purpose

of

the

lake is

floocl

control,

a-

hence, the

water

levc'l is:suhject

Lo

fluctuatio1

t'hrottghout

lhe

year

(i4ctlurney

and

Lar

intore

l980)

,

Swartener

anrJ

Buck ler

(

l9/!

)

founrJ

lhe

two

lakes

to he

similar

in

nrean

biomassr

nlgirrt

rlcnsiLy,

arrrl

,na-io.

-

taxononic

gt'oUp,cornposition.

'

Table

7'l Comparison

of

major

rnorphornelr

ic

characLerisLics

of Lrkes

Coffeen,

Sangchris,

and Slrelbyvi

I

la.

l,

::l

t

l'

I

I

...

I'

t'

::

I

:'

t

l'

l'

I

Parameter

Coffeen

Lake

Lnke

Sangchris

[-a ke

.

Shelbyvi

I le

Surface

area

r'ruun-iupirt--

:

Max

irnum

depbh

Vo I ume

Surface/volurne

rat i0

Vo

I

unre deve I

opment

Shore I

i ne deve

I oprnen

t

446 h.r

5.7

m

17,7

n

27

.2

x'106m3

0.16

rn-i

0,97

10.6

876

h a.'.

4.6 m

',

13,7

rn

37. 4

x

'l06rn3

0.2?n-l

l

.08

14

.2

4, 490

h <l

,r'

'

4.9

rn',

.

,

l9.B

nr'

267.0 x

l06qr3

,r

0, I

7nr-1.

0.75'

lt.7

l'

QJrg_lg$.Igd_"e_klgl.IgTojryg[g.[fef*!:ju

were

ccllecred fronr

Cof

feen

Lake

over

!.

the

course

of

the

two-year

strrdy; tlte

nurrtber of

taxa

Col

lectccl

rluring

a sirrgle

sampling

period

ranged

from

26 in

January

1979

to

56

in

Hay

1980.

Ourirrg'the

two-year

(1976-1977

)

study.

of

Lakes Sangchri's and

She'lhyv'il

le,

BB and

/3 t,oxa,

respectively,

were

collected

wit.h

r:anges

of 29,t0

48

taxa

f

ound

al

l.ake

,.

'

Sangchris and 24

to

44

taxa

at l-ake Shelbyville

(SwarJener

arrtl

Bircklgr

lg79).

The

tota! number

of

taxa'present

at.Coffeen'Lake

appears

muclr

larger th4n

llre

7.4

.:l

---

t,ol,al

taxd

at

Lakrls

5anqrhr-is

.:nd

Shtll:!";i!lr.;

hirwi,,.,_,r.,

fr:oin

tlre

latter

trri

lal.es'rrere

fi$t i{iefttrf

ierJ

r}n!i

t,ir{i

separate

oligochaetc

tax.r

wer.e

irJqrr-rt

if

ir:d f

r.oin

i.r1

f

1...1,1,

a{tditional

tar.a

ttre

total

at

cor'f

er:n

Lakr. | f,1'!

!

.,{itrrrri

Sangchris

and

ihelbyvi

l lc.

:; I

t:;i-:r:1r,.:Cl

ir,;

i'-l

lr:if

ed

':

,-l,;,r,r'l

trr'a.|,

.

*.i,',

il

-.

1i.il

.

',{'i

1,,,;,r1

!

tl."\'.j

t.l:1,

.;11

,gr'

ll,Jl.*r:,in

i..lhi,i

I

l-

l'

T

l'

l'

t

1..:,

l',

I

l'

I

Tab_|_9-!,-2..

g.gllllij-1 t!q.rt+q

!qr-t_qJ.

rtgllsity

an,1,:tiio;.*+:r

*t

Lakar

Coifet:r.r,

Sangchris,

and

Shelbyville.

fii

was

the

cas,: xiUi

l,ot

l)

t.tyd,

vJl1ls5

f 16rn

roffeen

Lake arrpr:ar

rlrnilar

to thos*

of Lhe

other

centrdl

lllinois

lakes (arr

irnproved

rnelhod

'of

enu$erating

otigocha;tei

aecou,rre,J

f

or.

Llre

r:1q,64

rlcnsity,at

':,

Cof feen

Lake

lleing

substantial

ly irigne

r

tlran t.he

ntlrer

i.il:1s);

howev,tr,

prg

values

liSl,ed for

al I

three

lakes

rrc

quit.rt

luw

whrrr

conpdrerl

t0 Lh0tc

9f

i!,1;,g5,

(1g57)

worldwide

sturly

of

?51

I

dt;.rs

ran.linq

f

r'onr lr

i,,;h

t,i

lo.*

llrtl,JrrcL

ivi

ty

in*

lowest rneon

biornass

reporled

by

llayel

,*a5

2,36{)

rnq/rn?

f irr

ls\cc

r-rf

the

f innish

'

region.

DaLa

from

a wirle

varie'"y

of l0kc!

s,r,nrrarir0d

try rlcrzel

ilg/5i also

suppor.t

Ihe

conc.lusion

that

Ihe

benlltic.corrununily

of

t]offeenll-ake,

nppe,lri

to

bc,

not

highly

prorluctive.

raltle

7.2. l4ean

toLal

bin,.Jss

,1rlt.| rJensity

of

r.he

hr-'rrlrric

COnmutlities

rlf

LakeS

Coffccn, 5art.jt.hr.is,,inrJ

She

llryv

i

I

le

.

t.ake

'{}itlrndss*

(

rng

lrn?;

0crrs i

L

y

(no./m21

Co f feen

Songchr

i

s ,

Shelbyvi

I

le

I

33q

|

3fli

l4l5

|

455

|

015

I

0Bl

'.'

Coffeen, Sangchfis,

ancl

Shelbyville'are

lrresented

n l,jgure

7.1..

At

Coffecrr

Lake,meandensityranger|from504orgdni,n''/,.'2irtJalrttaryl979to3,460

l97B to

2,776

ng/nZ

in

June l9S0

(biomdss

of

f''lollusc,l

exclurJ,:rj).

Me,rn

.:::

f":ttl.:

til biomasses

h,ere

generuity

to*ur.

during

ure

winter

morrrhn

anrl'

1,='

hi'gh€sL.iin

tlte

summerl,

a

pattern

of:'seasorral'f

luctual,ion

whi:ch

is,

unl..ike

that

::

-

*exclutles

weighl

of

,i4ollusca

:

.:

.

:'

,

Ihe

seasonol f

luctuat,ions,in rnean

l.otal

biornair

anrJ

nearr

LoIal

darrsiLy

at

Ldkes

:'.

:l

:

7r5

t:r:

---

::::::

::

.......

:.,,

.=a.:::

.-

:

',1

-::.'.::l

-l

''t

t,

,t'

"'

I

.

,1,

i

'l

.:

'l

l'

I

I

,l'

'l

t

''l

'l

:.:.::

-l.

-J

.,'.,t..,,

.

--ttj.i

l;

I,

/'

't

.l:

ii

jt'

Jr,

Jtt

Ji

j'

j:

i

J

|

i

:

Ii

I

il

.,1

i

i

r'

t/

\

i

,t

\

I|lt

I:

I

i

!'.

I

l',,:

t

I

I

\l-.i

\t-

\.

'\/'\

-,-t-/

'/

//

f

$Frlf

!1'

',:',:

'jtif:l$!.r':i-:-f

1;iifrl,iiift

i :'

1500.

30crJ

2500

2090

,:,

I 500

100.0

5Gg

0

4000

35r]0

Jrl00

2500

;:000

r 500

|

0G{l

500

i:::::.i:'..::::'

.'.

:

: .

.:;:a',j:

:

'-a:.'.:

='.;;;;;::,

aa.

:.:..-

'::

:.:

',

=,

::,...'..

=...r::

.

l{

r=irr:

'

F

::: .',4