Pengukuran Nilai Target Strength dan Densitas Ikan Pelagis di Perairan Rembang dengan "Sistem Akustik BIM Ganda"

(1)

ME

FEnR

OF

ME LORD

IS

ME

BECIHtlIHG

Of

W

L

E

D

G

E

:

BUT

FOOLS DESPISE WISDGii

N(D

IHSIRUCTIM1.

C P R O U E R B S 1 : 7

>

WIWUH XIIR I(MGUfiGMP RRHRSIR MU1 MH FRMNFIIRIKnHmII UMUX KESEJIIHII31RAH UWI MMJSIII ??

(2)

i

,/

i7ir

9 *-

I ';I

i

<

I

I / 1

<

PENGUKURAN NlLAl TARGET STRENGTH DAN DENSITAS

IKAN PELAGIS Dl PERAIRAN REMBANG DENGAN

"

SISTEM AKUSTIK B I M GANDA

'"

HENRY MUNANDAR MANIIC

C 26.0134

SKRIPSI

Sebagai Salah

Satu

Syarat

Mernperoleh Gelar

Sarjana

PROGRAM STUD1

ILMU DAN TEKNOLOGI KELAUTAN

FAKULTAS PERIKANAN

(3)

J u d u l S k r i p s i : Pengukuran n i l a i Target Strength

dan D e n s i t a s Ikan P e l a g i s d i

P e r a i r a n Renbang d e n g a n " S i s t e n

A k u s t i k B i n Ganda "

Nana t f a h a s i s w a : Henry Hunandar Hdnik

Nonor Pokok : C 26 -0134

Program S t u d i : I l n u dan ~ e k n o l o g i ' K e l a u t a n

I . K o n i s i P e n b i n b i n g

K e t u a

kc.

_{T o t o k} _{t o .} _MSc

A n g g o t a

1 1 . F a k u l t

(4)

R I NGEASAN

HENRY MUNANUAR M A N I C ( C 26.0134). PENGUKURAN NILAI

THRtiET STFiENGTH DAN DENSITAS IEAN FELAGIS DI FERAIfiAN

REMBGNG DENGAN " SISTEM AEUSTIK P I N GANDA "

( D i b a w a h b i m b i n g a n D r . I r . B o n a r F . P a s a r i b u d a n I r . T o t o k

H e s t i r i a n o t o , HSc)

P e n g k a j i a n s u m b e r d a y a i k a n p e l a g i s d e n g a n m e t o d e

a k u s t i k d i P e r a i r a n Rembang b e l u m a d a y a n g m e l a k u k a n .

M e n g i n g a t s u m b e r d a y a i k a n p e l a g i s i n i m e r u p a k a n penyum-

b a n g t e r b e s a r d a l a m p e m b a n g u n a n p e r i k a n a n maka d i p e r l u k a n

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

d e n s i t a s i k a n d a n d i s t r i b u s i n y a .

Scientific echosounder, k h u s u s n y a d e n g a n s i s t e m d u a l

b e a m t e l a h t e r b u k t i e f e k t i f u n t u k m e n d u g a n i l a i d e n s i t a s

i k a n p e l a g i s , k a r e n a s e c a r a a k u r a t d a p a t m e n g u k u r i n s i t u

target strength d a n d e n s i t a s r e l a t i f n y a m a s i n g - m a s i n g

d e n g a n dual beam processor d a n echo integrator. K e i s t i -

mewaan u t a m a s i s t e m d u a l beam i n i a d a l a h transducer

t e r d i r i d a r i d u a beam y a i t u narrow beam d a n wide beam

s e h i n g g a d a p a t m e n g u k u r target strength s e c a r a i n s i t u .

P e n e l i t i a n i n i b e r t u j u a n u n t u k m e n g u k u r n i l a i i n

s i t u target strength, m e n g a n a l i s i s d i s t r i b u s i target

strength i k a n p e l a g i s s e c a r a v e r t i k a l d a n h o r i z o n t a l d a n

m e n g a n a l i s i s n i l a i d e n s i t a s i k a n s e c a r a

v e r t i k a l d a n h o r i z o n t a l .

N i l a i i n s i t u target strength r a t a - r a t a p a d a s i a n g

h a r i a d a l a h -48,85 dB s e d a n g k a n n i l a i t a r g e t s t r e n g t h

(5)

r a t a - r a t a p a d a malam h a r i a d a l a h - 4 7 , 9 3 d B . N i l a i

t a r g e t s t r e n g t h r a t a - r a t a s i a n g l e b i h k e c i l d i b a n d i n g k a n

t a r g e t s t r e n g t h r a t a - r a t a malam h a r i . P e n y e b a b d a r i

p e r b e d a a n p e n g u k u r a n t i d a k d i k e t a h u i d e n g a n p a s t i t e t a p i

a d a b e b e r a p a k e m u n g k i n a n y a i t u t i n g k a h l a k u i k a n ( t i l t

a n g l e , s i f a t b e r g e r o m b o l ) d a n p e n g a r u h f a k t o r l i n g k u n g a n

a n t a r a l a i n s u h u d a n s a l i n i t a s .

S e b a r a n t a r g e t s t r e n g t h s e c a r a v e r t i k a l m e n u n j u k k a n

k e c e n d e r u n g a n bahwa n i l a i t a r g e t s t r e n g t h s e m a k i n b e s a r

d e n g a n b e r t a m b a h n y a k e d a l a m a n p e r a i r a n . K e c e n d e r u n g a n

i n i d i d u g a d i p e n g a r u h i o l e h k e b e r a d a a n d a r i i k a n d a s a r

( k h u s u s n y a i k a n y a n g u k u r a n n y a l e b i h b e s a r ) y a n g

m e n g a d a k a n migrasi s e d i k i t d i a t a s d a s a r p e r a i r a n .

S e b a r a n target s t r e n g t h s e c a r a h o r i z o n t a l m e n u n j u k k a n

n i l a i y a n g b e r v a r i a s i y a n g mana d i s e b a b k a n o l e h

h e r u b a h n y a d i s t r i b u s i d a n k o m p o s i s i h o r i z o n t a l i k a n

.

B e s a r n y a n i l a i r a t a - r a t a d e n s i t a s i k a n d i s e k i t a r

3

p e r a i r a n Rembang p a d a s i a n g h a r i a d a l a h 0 , 0 0 7 4 3 kg/m d a n

p a d a m a l a m h a r i a d a l a h 0 , 0 2 1 1 0 kg/m3, y a n g t e r d i r i d a r i

f a m i l i C l u p e i d a e ( t e m b a n g , j u w i , j a p u h ) , f a m i l i C a r a n g i -

dae ( l a y a n g , s e l a r ) d a n f a m i l i S c r o m b r i d a e ( k e n b u n g ) .

P a d a s i a n g h a r i , i k a n m e n y e b a r d a l a m kolom p e r a i r a n

d a r i k e d a l a m a n 2-62 m e t e r , d a n d e n s i t a s t e r t i n g g i b e r a d a

p a d a k e d a l a m a n 4 2 - 5 2 m e t e r y a i t u 0 . 0 2 1 6 kg/m3. P a d a

m a l a m h a r i d e n s i t a s t e r t i n g g i p a d a k e d a l a m a n 5 2 - 6 2 m e t e r

(6)

d a n s e m a k i n menurun d e n g a n b e r k u r a n g n y a k e d a l a m a n .

U e n s i t a s t e r t i n g g i p a d a t r e k a r b i t r a r y i n i p a d a p u k u l

0 4 . 0 0 w a k t u s e t e m p a t . D i s t r i b u s i h o r i z o n t a l i k a n p a d a

s i a n g h a r i b e r a d a p a d a d a e r a h a k h i r d a r i t r e k d e n g a n

k e p a d a t a n 0 . 0 0 5 9 kg/m3, s e d a n g k a n p a d a malam h a r i t e r k o n -

s e n t r a s i p a d s d a e r a h t e n g a h d a n a k h i r d a r i t r e k . P e r b e -

d a a n d e n s i t a s a n t a r a s i a n g h a r i d a n m a l a m h a r i d a p a t

d i s e b a b k a n o l e h s i f a t m e n g g e r o m b o l i k a n - i k a n p e l a g i s p a d a

s i a n g h a r i p a d a l a p i s a n p e r a i r a n y a n g l e b i h d a l a m .

A p a b i l a d u a i n d i v i d u i k a n b e r a d a p a d a beam a k u s t i k

d e n g a n j a r a k k u r a n g d a r i C T / ~ , maka e c h o y a n g k e m b a l i

a k a n o v e r l a p , s e h i n g g a h a s i l p e n d u g a a n m e n j a d i l e b i h

k e c i l d a r i y a n g s e b e n a r n y a . D e m i k i a n j u g a p e n g a r u h

p e r b e d a a n t i n g k a h l a k u ( s u d u t o r i e n t a s i ) i k a n p a d a s i a n g

h a r i d a n malam h a r i s e l a m a s u r v e i , s e h i n g g a u n t u k i k a n

d e n g a n j e n i s d a n u k u r a n y a n g s a m a , n i l a i t a r g e t strength-

n y a b e r b e d a

.

P e n g e l o m p o k a n i k a n p a d a l a p i s a n p e r a i r a n y a n g c e n -

d e r u n g k e p e r m u k a a n p a d a s i a n g h a r i d a p a t d i s e b a b k a n o l e h

p e n g a r u h f a k t o r l i n g k u n g a n p e r a i r a n . Suhu d a n s a l i n i t a s

p e r a i r a n selama s u r v e i a d a l a h 3 1 . 0 OC d a n 34.5 O/00 y a n g

b e r b e d a d i a t a s n i l a i s u h u r a t a - r a t a l a u t Jawa s e p a n j a n g

t a h u n ( 2 8 OC) d a n s a l i n i t a s b u l a n A p r i l ( 3 0 O/00).

(7)

KATA

PENGANTAR

S e t e l a h m e l a l u i s e r a n g k a i a n k e g i a t a n m u l a i d a r i

p e r e n c a n a a n , p e l a k s a n a a n d a n a n a l i s a d a t a , maka p a d a

a k h i r n y a p e n u l i s d a p a t m e n y e l e s a i k a n t u g a s a k h i r y a k n i

p e n u l i s a n s k r i p s i i n i . S k r i p s i m e r u p a k a n s a l a h s a t u

p e r s y a r a t a n u n t u k m e m p e r o l e h g e l a r s a r j a n a S t r a t a

-

1 d i

P r o g r a m S t u d i I l m u d a n T e k n o l o g i K e l a u t a n , F a k u l t a s

P e r i k a n a n , I n s t i t u t P e r t a n i a n B o g o r .

S k r i p s i i n i d i s u s u n b e r d a s a r k a n s u r v a i a k u s t i k y a n g

d i l a k s a n a k a n b e k e r j a s a m a d e n g a n J a v a Sea P e l a g i c F i s h e r y

A s s e s s m e n t P r o j e c t d i p e r a i r a n L a u t J a w a .

P a d a k e s e m p a t a n i n i p e n u l i s m e n g u c a p k a n t e r i m a k a s i h

k e p a d a :

(1) D r . I r . B o n a r P . P a s a r i b u , MSc. d a n I r . T o t o k

H e s t i r i a n o t o , MSc. s e l a k u d o s e n p e m b i m b i n g .

( 2 ) Dr. I I Nyoman A r n a y a , Hsc d a n I r . James P .

P a n j a i t a n H . Eng y a n g t e l a h b a n y a k membantu

selama p e m r o s e s a n d a t a .

( 3 ) H r . J . R . D u r a n d d a n D r . 1 J . Widodo s e b a g a i

d i r e k t u r d a n w a k i l d i r e k t u r J a v a S e a P e l a g i c

F i s h e r y A s s e s s m e n t P r o j e c t .

( 4 ) H r . D i d i e r P e t i t d a n M r . P a s c a 1 C o t e 1 s e b a g a i

(8)

( 5 ) I r . D u t o N u g r o h o y a n g t e l a h b a n y a k membantu d a r i

awal h i n g g a a k h i r p e l a k s a n a a n s u r v e i a k u s t i k .

( 6 ) B a p a k S a r w o t o s e b a g a i p e j a b a t K a p t e n k a p a l B a w a l P u t i h I b e s e r t a s e l u r u h Anak Buah Kapal.

( 7 ) Rekan

-

r e k a n selama p e n e l i t i a n ( E m a n u e l , B u d i , I n d r a , R i d w a n , A l i d a n S y a h y a d i )

( 8 ) I r . J o n s o n L . G a o l y a n g t e l a h m e m b e r i k a n b a n t u a n .

( 9 ) K a k a k t e r c i n t a I r . I d a H e n r a w a t y M a n i k .

(10) B a p a k J o h n L u n r a n g b e s e r t a k e l u a r g a y a n g t e l a h

m e m b e r i k a n b a n t u a n m a t e r i l

(11) B a p a k d a n M a m a b e s e r t a k e l u a r g a y a n g m e m b e r i

d o r o n g a n h i n g g a t u g a s a k h i r i n i t e r s e l e s a i k a n

d e n g a n b a i k .

P e n u l i s b e r h a r a p mudah-mudahan S k r i p s i i n i b e r m a n f a a t

b a g i y a n g m e n e r l u k a n n y a .

B o g o r , A g u s t u s 1 9 9 4

(9)

DAFTAR IS1

H a l

RINGKASAN

...

i

KATA PENGANTAR ...-...iv

DAFTAR I S 1

. . .

v i

DAFTAR GAHBAR

...

v i i i

DAFTAR T A B E L

...

x

DAFTAR LAHPIRAN

. . .

x i

I . PENDAHULUAN 1

1 . 1 L a t a r B e l a k a n g

. . .

1 1 . 2 T u j u a n d a n M a n f a a t

. . .

2 1 . 3 Waktu d a n T e m p a t

. . .

3

1 1 . T I N J A U A N PUSTAKA 4

2 . 1 T a r g e t S t r e n g t h

. . .

4 2 . 1 . 1 F a k t o r

-

f a k t o r y a n g mempengaruhi

T a r g e t S t r e n g t h

. . .

5 2 . 1 . 2 Metode P e n g u k u r a n T a r g e t S t r e n g t h 9 2 . 1 . 3 P e n g u k u r a n T a r g e t S t r e n g t h

d e n g a n D u a l Beam A c o u s t i c S y s t e m 9 2 . 2 Hubungan T a r g e t S t r e n g t h d e n g a n p a n j a n g

i k a n

. . .

1 8 2 . 3 D e n s i t a s i k a n

. . .

20

111. K O N D I S I O S E A N O G R A l I DAN

KEADAAN

PERIKANAN

P E L A G I S D I L O K A S I P E N E L I T I A N 2 6

3 . 1 Suhu

. . .

2 6 3 . 2 S a l i n i t a s

. . .

27 3 . 3 Massa a i r

. . .

27 3 . 4 A r u s

. . .

2 8 3 . 5 Keadaan P e r i k a n a n P e l a g i s

. . .

29 3 . 5 . 1 Sumber d a y a i k a n

. . .

29 3 . 5 . 2 A l a t t a n g k a p

. . .

3 1 3 . 5 . 3 N e l a y a n

. . .

3 1

(10)

4 . 3 . 4 B o t o l Nansen

. . .

3 4 4 . 3 . 5 Dan l a i n - l a i n

. . .

3 4 4 . 3 K a l i b r a s i A l a t

. . .

3 8 4 . 4 D e s a i n S u r v e i

. . .

3 9 4 . 5 Metode P e r o l e h a n D a t a

. . .

4 0 4 . 6 Metode P e m r o s e s a n D a t a

. . .

4 4 4 . 7 Metode A n a l i s i s D a t a

. . .

4 4 4 . 7 . 1 A n a l i s i s N i l a i T a r g e t S t r e n g t h

. . . .

4 4 4 . 7 . 2 A n a l i s i s N i l a i D e n s i t a s I k a n

. . .

4 6

V

.

HASIL 5 2

. . .

5 . 1 J e n i s i k a n y a n g t e r d e t e k s i 5 2 5 . 2 N i l a i T a r g e t S t r e n g t h Dengan T h r e s h o l d

y a n g b e r b e d a

. . .

5 2 5 . 3 S e b a r a n n i l a i t a r g e t s t r e n g t h s e c a r a

v e r t i k a l

. . .

h o r i z o n t a l

. . .

5 8 5 . 5 N i l a i t a r g e t s t r e n g t h r a t a - r a t a

. . .

6 0 5 . 6 D e n s i t a s I k a n

. . .

6 3 5 . 7 S e b a r a n n i l a i d e n s i t a s i k a n s e c a r a

h o r i z o n t a l

. . .

v e r t i k a l

. . .

6 5

V I

.

KESIHPULAN DAN SARAN 7 1

. . .

7 . 1 K e s i m p u l a n 7 1

7 . 2 S a r a n

. . .

7 1

. . .

DAFTAR PUSTAKA 7 3

. . .

LAHPIRAN-LAHPIRAN 7 6

(11)

(12)

(13)

(14)

(15)

(16)

(17)

(18)

(19)

(20)

(21)

(22)

(23)

(24)

(25)

(26)

(27)

(28)

(29)

(30)

(31)

(32)

(33)

(34)

(35)

(36)

(37)

(38)

(39)

(40)

(41)

(42)

(43)

(44)

(45)

(46)

(47)

(48)

(49)

(50)

(51)

(52)

(53)

(54)

(55)

(56)

(57)

(58)

(59)

(60)

(61)

(62)

(63)

(64)

(65)

(66)

(67)

(68)

(69)

(70)

(71)

(72)

(73)

(74)

(75)

(76)

(77)

(78)

(79)

(80)

(81)

(82)

(83)

(84)

(85)

(86)

(87)

(88)

(89)

(90)

(91)

(92)

(93)

(94)

(95)

(96)

(97)

(98)

(99)

(100)

(101)

(102)

(103)

(104)

(105)

(106)

(107)

(108)

(109)

(110)

(111)

(112)

(113)

ME

FEnR

OF

ME LORD

IS

ME

BECIHtlIHG

Of

W

L

E

D

G

E

:

BUT

FOOLS DESPISE WISDGii

N(D

IHSIRUCTIM1.

C P R O U E R B S 1 : 7

>

WIWUH XIIR I(MGUfiGMP RRHRSIR MU1 MH FRMNFIIRIKnHmII UMUX KESEJIIHII31RAH UWI MMJSIII ??

(114)

i

,/

i7ir

9 *-

I ';I

i

<

I

I / 1

<

PENGUKURAN NlLAl TARGET STRENGTH DAN DENSITAS

IKAN PELAGIS Dl PERAIRAN REMBANG DENGAN

"

SISTEM AKUSTIK B I M GANDA

'"

HENRY MUNANDAR MANIIC

C 26.0134

SKRIPSI

Sebagai Salah

Satu

Syarat

Mernperoleh Gelar

Sarjana

PROGRAM STUD1

ILMU DAN TEKNOLOGI KELAUTAN

FAKULTAS PERIKANAN

(115)

J u d u l S k r i p s i : Pengukuran n i l a i Target Strength

dan D e n s i t a s Ikan P e l a g i s d i

P e r a i r a n Renbang d e n g a n " S i s t e n

A k u s t i k B i n Ganda "

Nana t f a h a s i s w a : Henry Hunandar Hdnik

Nonor Pokok : C 26 -0134

Program S t u d i : I l n u dan ~ e k n o l o g i ' K e l a u t a n

I . K o n i s i P e n b i n b i n g

K e t u a

kc.

_{T o t o k} _{t o .} _MSc

A n g g o t a

1 1 . F a k u l t

(116)