Pengaruh Curah Hujan terhadap Infiltrasi pada Tanah Terbuka

(1)

PENGARUN CUBAN NUJAN

TERNADAP

INLFlLTRWSl

PABA TANAH BERBUKA

Y U S U F F

23.0679

1991

FAKULTAS

TEKNOLOGI

PERTANIAN

INSTITUT PERTANlAN

BOGOR

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YUSUF F 2 3 . 0 6 7 9 . P e n g a r u h C u r a h H u j a n T e r h a d a p I n f i l -

t r a s i P a d a T a n a h T e r b u k a .

Dibawah b i m b i n g a n I R

.

SUKANDI SUKARTAATMADJA,

HS

.

R I N G K e S A N

K e t e r b a t a s a n d a n k e t i d a k t e r a t u r a n c u r a h h u j a n

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

p e r t a n i a n . B e r b a g a i u s a h a p e r b a i k a n d i t e m p u h g u n a me-

n i n g k a t k a n i n t e n s i f i k a s i l a h a n . P e n g a t u r a n j a d w a l

t a n a m merupakan s a l a h s a t u c a r a d a l a m u s a h a i n i .

S e l a i n i t u u s a h a p e r b a i k a n f i s i k t a n a h j u g a d i l a k u k a n .

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

p o s i t i f t e r h a d a p d a y a s i m p a n a i r t a n a h , s e l a i n j u g a menambah k e s u b u r a n t a n a h . P e n e l i t i a n i n i b e r t u j u a n

m e m p e l a j a r i p e n g a r u h c u r a h h u j a n t e r h a d a p i n f i l t r a s i

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

h e w a n ) .

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

p e n t i n g d a r i k a r a k t e r i s t i k c u r a h h u j a n a d a l a h i n t e n s i -

t a s , f r e k u e n s i d a n l u a s d a e r a h p e n y e b a r a n n y a . J u m l a h a i r y a n g masuk k e d a l a m t a n a h d i p e n g a r u h i o l e h s i f a t

f i s i k t a n a h , k a d a r a i r m u l a - m u l a , d a n c u r a h h u j a n y a n g j a t u h d i a t a s n y a . Banyak s i f a t f i s i k permukan t a n a h

b e r u b a h k a r e n a tumbukan b u t i r - b u t i r h u j a n

.

D a t a c u r a h h u j a n d i p e r o l e h d a r i a n a l i s a CHART OTA

No. CR-100-1 d a r i A R R y a n g d i p a s a n g d i l o k a s i p e n e l i - t i a n . J u m l a h i n f i l t r a s i y a n g d i h a s i l k a n s e t i a p c u r a h

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

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

h u j a n t e r i n f i l t r a s i d i l a k u k a n d e n g a n membandingkan

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

d a r i a n a l i s a d a t a i n f i l t r a s i p e n g u k u r a n l a p a n g d e n g a n

double

ring infiltrometer

p e r p e r i o d e 15 m e n i t p e r

c u r a h h u j a n p e r i o d e 24 j a m , d e n g a n m e m p e r h a t i k a n k a d a r

a i r mula-mula. P e n g a r u h c u r a h h u j a n t e r h a d a p i n f i l t r a -

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

A n a l i s a d a t a i n f i l t r a s i d a r i p e n g u k u r a n d i l a p a n g ,

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

A n a l i s a d a t a y a n g sama d e n g a n menggunakan p e r s a m a a n

K o s t i a k o v d i p e r o l e h p e r s a m a a n i n f i l t r a s i k u m u l a t i f

s e b a g a i b e r i k u t :

F A l

( t a n p a BO, u l .

I )

=

0.780

FA2 ( t a n p a BO, u l . 11)

=

0.394

t

0.534

FBI

(BO ayam, u l . I )

=

1.289

F~~

(BO

ayam, u l .

I L )

=

1.092 t'3.428

FC1 (BO s a p i ,

u l .

I ) = 0 . 6 6 3

FC2

(BO s a p i , u l . 11)

=

_1.547 _{d a r i persa-}

maan-persamaan t e r s e b u t d i d u g a t o t a l c u r a h h u j a n t e r i n -

f i l t r a s i . L f i p e r o l e h h a s i l r a t a - r a t a c u r a h h u j a n t e r i n - f i l t r a s i A ( t a n p a BO)

=

601.11,

B

(BO ayam)

=

792.61,

d a n C _(BO_{s a p i )}

=

_500.61. _{I n E i l t r a s i h a s i l p e n g u k u r a n}

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C (BO s a p i )

=

_{1 0 1 6 . 7 1 .} _{H a s i l a n a l i s a s t a t i s t i k menun-}

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

d i t e r i m a . P e r b e d a a n t e r s e b u t d i s e b a b k a n b a t a s k e t e l i -

t i a n maksimum d a r i p e n d u g a a n c u r a h h u j a n t e r i n f i l t r a s i

u n t a k p e r i o d e 15 m e n i t ( a n a l i s a CHART OTA).

U j i k e r a g a m a n m e n u n j u k k a n bahwa c u r a h h u j a n ( 5 5 %

b e r p o l a a d v e n c e d ) b e r p e n g a r u h s a n g a t b e r b e d a n y a t a

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

b e r p e n g a r u h t i d a k b e r b e d a n y a t a . Hal i n i d i s e b a b k a n o l e h s e l a n g w a k t u a n t a r a p e m b e r i a n b a h a n o r g a n i k s e b a -

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

lama

(f 2 b u l a n ) . H a s i l u j i r e g r e s i d a r i p e r s a m a a n - p e r s a - maan hubungan c u r a h h u j a n t e r h a d a p i n f i l t r a s i p a d a

t a n a h t e r b u k a y a n g d i b e r i b a h a n o r g a n i k ( k o t o r a n hewan)

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

s a n g a t n y a t a , s e d a n g k a n p a r a m e t e r - p a r a m e t e r l a i n n y a

b e r p e n g a r u h t i d a k n y a t a . P e n g a r u h c u r a h h u j a n t e r h a d a p

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

(BO k o t o r a n hewan) d i g a m b a r k a n o l e h p e r s a m a a n :

lp (80 ayad = 27.911CH t 1.034t

-

0.0241S0 t 0.001E130

-

78.546 (R = 0.9901, atau = _41.26XH

-

_145.661 _(R= _0.905)

IC

(80 sapi) = 28.495CH + 1.690t 4 0.3751S0 + O.OOIEI;O

-

63.679 (R = 0.991), atau

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P E N G A R U H C U R A H H U J A N T E R H A D A P I N F I L T R A S I

P A D A T A N A H T E R B U K A

SKRIPSI

s e b a g a i s a l a h s a t u s y a r a t u n t u k memperoleh g e l a r

SARJBHA TEKNOLOGI PBRTBHIAN

p a d a j u r u s a n HEgLUilISASI PERTANIAN

F a k u l t a s T e k n o l o g i P e r t a n i a n

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

O l e h

Y U S U F

F 23 0679

1991

I N S T I T U T P E R T A N I A N BQGQR

F A K U L T A S T E K N O L O G I P E R T A N I A N

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INSTITUT PERTANIAN BOGOR FAKULTAS TEKNOLOGI PERTANIAN

P E N G A R U W C U R A H H U J A N T E R H A D A P I N F I L T R A S I

P A D A T A N A W T E R B U K A

S K R I F S I

s e b a g a i s a l a h s a t u s y a r a t u n t u k m e m p e r o l e h g e l a r SARJBNB TEKlilDLOGI PERTBNIBN

p a d a j u r u s a n H E W I S A S 1 PERTBNIBtU F a k u l t a s T e k n o l o g i P e r t a n i a n

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

O l e h Y U S U P

P

23 0679

T a n g g a l l u l u s : 2 1 HE1 1 9 9 1

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KATA PENGANTAR

B i s m i l l a a h i r r a h m a a n i r r a h i i m ,

A l h a m d u l i l l a h , p u j i s y u k u r p e n u l i s p a n j a t k a n k e

h a d i r a t A l l a h SWT. K a r e n a k e k u a t a n . k a r u n i a , d a n

r a h m a t A l l a h t a ' a l a s e m a t a s k r i p s i i n i d a p a t d i s e l e s a i -

k a n

.

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. I r . H . S u k a n d i S u k a r t a a t m a d j a , MS s e l a k u d o s e n p e m b i m b i n g

.

2 . I r . Y a n u a r J . P . d a n I r . I N e n g a h S u a s t a w a s e l a k u d o s e n p e n g u j i

.

3 . Semua p i h a k y a n g m e m b a n t u p e n u l i s b a i k s e c a r a

m o r i l rnaupun m a t e r i i l g u n a p e n y u s u n a n s k r i p s i

i n i .

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

i n i d a n p e n u l i s a n s e l a n j u t n y a s a n g a t p e n u l i s p e r l u k a n .

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DAFTAR IS1

h a l a m a n

. . .

KATA PENGANTAR i i i

DAFTAR I S 1

. . .

i v

DAFTAR TABEL

. . .

v i

. . .

DAFTAR GAMBAR v i i

. . .

DAFTAR LAMPIRAN v i i i

I

.

PENDAHULUAN

. . .

1

A

.

LATAR BELAKANG

. . .

2

B

.

TUJUAN

.

3

I1

.

TINJAUAN PUSTAKA

. . .

4

A

.

CURAHHUJAN

. . .

4

B

.

INFILTRASI

.

6

. . .

C

.

A I R TANAH 1 7

. . .

1

.

P e r g e r a k a n A i r T a n a h 1 7

. . .

2

.

K a p a s i t a s T a n a h Menyimpan A i r 20

. . .

3

.

C a r a M e m p e r b e s a r K a p a s i t a s I n f i l t r a s i 20

. . .

4

.

P e n e t a p a n Kelembaban T a n a h 2 3

. . .

I T

.

XETODE PEBELITIAN 2 6

. . .

A

.

WAKTU DAN TEMPAT 26

. . .

B

.

_{BAHAN DAN ALAT} _{2 6}

. . .

C

.

METODE PENELITIAN 27

. . . .

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H a l a m a n 4

.

P e n g u k u r a n I n f i l t r a s i

. . .

4

.

P e n d u g a a n C u r a h H u j a n T e r i n f i l t r a s i

5

.

H u b u n g a n C u r a h H u j a n d a n I n f i l t r a s i

. . .

I V

.

HASIL DAN PEMBAHASAN

A

.

SIFAT F I S I K TANAH

. . .

B

.

CURAHHUJAN

. . .

C

.

INFILTRASI

D

.

KELEMBABAN TANAH

. . .

E

.

CURAH H U J A N TERINFILTRASI

. . .

F

.

HUBUNGAN CURAH H U J A N DENGAN INFILTRASI

V

.

KESIMPULAN DAN SARAN

. . .

A

.

KESIMPULAN

. . .

B

.

SARAN

LAMPIRAN

.

(10)

DaFTAR

TABBL

halaman

T a b e l 1 . K a p a s i t a s i n f i l t r a s i b e b e r a p a t i p e t a n a h

d a r i p e n g u k u r a n l a p a n g

. . .

9

T a b e l 2 . Metode p e n d u g a a n k a p a s i t a s i n f i l t r a s i d e n g a n

. . .

rumus e m p i r i s 14

T a b e l 3 . Kandungan a i r t a n a h d a n p e r m e a b i l i t a s t a n a h

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

. . .

2 1

T a b e l 4 . R a t a - r a t a s i f a t f i s i k t a n a h d i l o k a s i p e n e l i - t i a n ( L a b o r a t o r i u m F i s i k a T a n a h , J u r u s a n I l m u

. . .

i l m u T a n a h , FAPERTA, I P B ) 3 6 T a b e l 5 . Hasil a n a l i s a c u r a h h u j a n d i l o k a s i p e n e l i t i a n 37 T a b e l 6 . P o l a i n f i l t r a s i d a r i p e r s a m a a n K o s t i a k o v y a n g

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

. . .

p e n g g e n a n g a n 3 9

T a b e l 7 . P o l a i n f i l t r a s i d a r i p e r s a m a a n P h i l i p y a n g d i d a p a t d e n g a n c a r a p e n g u k u r a n i n f i l t r a s i

p e n g g e n a n g a n

. . .

4 0

T a b e l 8 . R a t a - r a t a a i r t e r s i m p a n s e t i a p k e j a d i a n h u j a n 4 3 T a b e l 9 . C u r a h h u j a n d a n i n f i l t r a s i y a n g d i h a s i l k a n 4 7

T a b e l 1 0 . P e n g a r u h c u r a h h u j a n t e r h a d a p i n f i l t r a s i p a d a

[image:10.530.51.504.42.486.2]

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PENGARUN CUBAN NUJAN

TERNADAP

INLFlLTRWSl

PABA TANAH BERBUKA

Y U S U F F

23.0679

1991

FAKULTAS

TEKNOLOGI

PERTANIAN

INSTITUT PERTANlAN

BOGOR

(116)