Mofometri DAS dan Aplikasinya untuk mengetahui karakteristik dan stadium erosi DAS Cikeruh, Kabupaten Sumedang, Provinsi Jawa Barat.
DAFTAR ISI
Halaman
KATA PENGANTAR .................................................................................
iv
ABSTRAK ....................................................................................................
vi
ABSTRACT ...................................................................................................
vii
DAFTAR ISI ................................................................................................
viii
DAFTAR GAMBAR ...................................................................................
xii
DAFTAR TABEL ........................................................................................
xiv
BAB I
BAB II
PENDAHULUAN .......................................................................
1
1.1
Latar Belakang .........................................................
1
1.2
Identifikasi Masalah .................................................
2
1.3
Maksud dan Tujuan ....................................................
2
1.4
Lokasi Daerah Penelitian ...........................................
3
TNJAUAN PUSTAKA ................................................................
4
2.1 Fisiografi Regional ................................................................
4
2.2 Stratigrafi Regional ...............................................................
5
2.3 Morfometri DAS ...................................................................
7
2.3.1 Pola Aliran Sungai .........................................................
7
2.3.2 Luas, Panjang dan Lebar DAS .....................................
8
2.3.3 Bentuk DAS dan Rasio Kebundaran ............................
8
2.3.4 Orde dan Tingkat Percabangan Sungai ........................
9
2.3.5 Kerapatan Pengaliran Sungai .......................................
10
2.4 Aspek Hipsometri ..................................................................
10
2.4.1 Nilai Ketinggian Daerah Tiap n Meter (h) ...................
11
2.4.2 Nilai Ketinggian Daerah Maksimum (H) .....................
11
2.4.3 Nilai Luas Daerah Tiap ketinggian n Meter (a) .......
12
2.4.4 Nilai Luas Daerah Maksimum (A) ..............................
12
2.4.5 Stadium Erosi................................................................
12
2.4.5.1 Stadium Erosi Muda............................................
13
viii
2.4.5.2 Stadium Erosi Menengah.....................................
13
2.4.5.3 Stadium Erosi Tua..............................................
14
BAB III METODE PENELITIAN .............................................................
15
3.1 Objek Penelitian ....................................................................
15
3.2 Alat dan Bahan Penelitian .....................................................
15
3.3 Tahapan Penelitian ................................................................
16
3.3.1 Tahap Persiapan ............................................................
16
3.3.2 Tahap Pengumpulan Data .............................................
17
3.3.3 Tahap Pengolahan dan Analisis Data ...........................
17
3.3.3.1 Analisis Karakteristik Morfometri ...................
17
3.3.3.1.1 Pola Aliran Sungai ...........................
18
3.3.3.1.2 Luas, Panjang, Lebar DAS ..............
20
3.3.3.1.3 Bentuk dan Rasio Kebundaran DAS
21
3.3.3.1.4 Rasio Cabang Sungai .......................
22
3.3.3.1.5 Kerapatan Sungai .............................
23
3.3.3.2 Analisis Variabel Hipsometri ............................
24
3.3.3.2.1 Nilai Ketinggian Daerah Tiap 25 MeTer (h) ...............................................
25
3.3.3.2.2 Nilai Ketinggian Daerah Maksimum (H) 25
3.3.3.2.3 Nilai Luas Daerah Tiap Ketinggian 25
Meter (a) ............................................
25
3.3.3.2.4 Nilai Luas Daerah Maksimum (A) ....
26
3.3.3.2.5 Penentuan Stadium Erosi ...................
27
3.3.4 Tahap Penyusunan Laporan ..........................................
28
BAB IV HASIL DAN PEMBAHASAN ....................................................
30
4.1 Morfometri DAS Cikeruh .....................................................
30
4.1.1 Pola Aliran Sungai ........................................................
31
4.1.2 Luas, Panjang, Lebar DAS ...........................................
32
4.1.3 Bentuk DAS dan Rasio Kebundaran ............................
41
4.1.4 Rasio Cabang Sungai ...................................................
42
4.1.5 Kerapatan Sungai .........................................................
45
ix
4.2 Analisis Variabel Hipsometri .................................................
49
4.2.1 DAS Cikeruh ................................................................
49
4.2.2 Sub DAS Orde 4 ...........................................................
51
4.2.3 Sub DAS Orde 3 ...........................................................
55
4.2.4 Sub DAS Orde 2 ...........................................................
65
4.3 Respon Variabel Hipsometri Terhadap Variasi Litologi .......
71
KESIMPULAN ............................................................................
74
DAFTAR PUSTAKA ...................................................................................
76
BAB V
LAMPIRAN 1 Peta Sebaran Sub DAS Orde 1 Cikeruh
LAMPIRAN 2 Peta Sebaran Sub DAS Orde 2 Cikeruh
LAMPIRAN 3 Peta Sebaran Sub DAS Orde 3 Cikeruh
LAMPIRAN 4 Peta Sebaran Sub DAS Orde 4 Cikeruh
LAMPIRAN 5 Peta Hipsometri Interval 25 m
LAMPIRAN 6 Hasil Perhitungan Variabel Morfometri
LAMPIRAN 7 Hasil Perhitungan Variabel Hipsometri
x
DAFTAR GAMBAR
Gambar
Halaman
1.1
Lokasi Daerah Penelitian .............................................................
4
2.1
Pembagian fisiografi Jawa Barat (Van Bemmelen, 1949) ...........
5
2.2
Peta Geologi Daerah Penelitian (Silitonga, 2003) ........................
6
2.3
Berbagai macam bentuk DAS; A. Bentuk DAS bulu burung; B.
bentuk DAS radial; C. Bentuk DAS paralel (Ramdan, 2006)…...
9
2.4
Penentuan orde sungai menurut Strahler ......................................
10
2.5
Kurva hipsometri stadium erosi muda ..........................................
13
2.6
Kurva hipsometri stadium erosi menengah...................................
14
2.7
Kurva hipsometri stadium erosi tua ..............................................
14
3.1
Pola pengaliran sungai menurut Howard (1967); A. Pola
pengaliran dasar; B - C. Pola pengaliran modifikasi ...................
3.2
20
Berbagai macam bentuk DAS (Ramdan, 2006); A. Bentuk DAS bulu
burung; B. Bentuk DAS radial; C. Bentuk DAS paralel ......................
21
3.3
Penentuan orde sungai Metode Strahler .............................................
23
3.4
Ilustrasi Perhitungan Kurva Hipsometri (Strahler,1952) ....................
26
3.5
Kurva Hipsometri Muda (A); Menengah (B); dan Tua (C) (Strahler,
1952)…………………………………………………………….
27
3.6
Bagan alir penelitian ....................................................................
29
4. 1
Morfologi DAS Cikeruh ……………………...............................
31
4.2
Pola Pengaliran Daerah Penelitian ...............................................
32
xi
4.3
Sebaran Sub DAS Orde 1 Pada DAS Cikeruh .............................
36
4.4
Sebaran Sub DAS Orde 2 Pada DAS Cikeruh ..............................
38
4.5
Sebaran Sub DAS Orde 3 Pada DAS Cikeruh ..............................
39
4.6
Sebaran Sub DAS Orde 4 Pada DAS Cikeruh ..............................
40
4.7
Interval Hipsometri DAS Cikeruh ................................................
49
4.8
Kurva Hipsometri DAS Cikeruh...................................................
50
4.9
Interval Hipsometri Sub DAS Orde 4 D1 .....................................
51
4.10
Kurva Hipsometri Sub DAS Orde 4 D1 .......................................
51
4.11
Interval Hipsometri Sub DAS Orde 4 D2 .....................................
52
4.12
Kurva Hipsometri Sub DAS Orde 4 D2 .......................................
53
4.13
Interval Hipsometri Sub DAS Orde 4 D3 .....................................
53
4.14
Kurva Hipsometri Sub DAS Orde 4 D3 .......................................
54
4.15
Interval Hipsometri Sub DAS Orde 3 C1 .....................................
55
4.16
Kurva Hipsometri Sub DAS Orde 3 C1........................................
55
4.17
Interval Hipsometri Sub DAS Orde 3 C2 .....................................
56
4.18
Kurva Hipsometri Sub DAS Orde 3 C2 ........................................
57
4.19
Interval Hipsometri Sub DAS Orde 3 C3 .....................................
57
4.20
Kurva Hipsometri Sub DAS Orde 3 C3........................................
58
4.21
Interval Hipsometri Sub DAS Orde 3 C4 .....................................
59
4.22
Kurva Hipsometri Sub DAS Orde 3 C4........................................
59
4.23
Interval Hipsometri Sub DAS Orde 3 C5 .....................................
60
4.24
Kurva Hipsometri Sub DAS Orde 3 C5 ........................................
61
4.25
Interval Hipsometri Sub DAS Orde 3 C6 .....................................
62
4.26
Kurva Hipsometri Sub DAS Orde 3 C6........................................
62
xii
4.27
Interval Hipsometri Sub DAS Orde 3 C7 .....................................
63
4.28
Kurva Hipsometri Sub DAS Orde 3 C7........................................
64
4.29
Interval Hipsometri Sub DAS Orde 2 B6 .....................................
65
4.30
Kurva Hipsometri Sub DAS Orde 2 B6 ........................................
65
4.31
Interval Hipsometri Sub DAS Orde 2 B18 ...................................
66
4.32
Kurva Hipsometri Sub DAS Orde 2 B18 ......................................
67
4.33
Interval Hipsometri Sub DAS Orde 2 B19 ...................................
67
4.34
Kurva Hipsometri Sub DAS Orde 2 B19 ......................................
68
4.35
Interval Hipsometri Sub DAS Orde 2 B20 ...................................
69
4.36
Kurva Hipsometri Sub DAS Orde 2 B20 ......................................
69
4.37
Interval Hipsometri Sub DAS Orde 2 B24 ...................................
70
4.38
Kurva Hipsometri Sub DAS Orde 2 B24 ......................................
71
4.39
Perbandingan Kurva Hipsometri pada Sub DAS Orde 2 Beserta
Nilai Dd .........................................................................................
xiii
72
DAFTAR TABEL
Tabel
Halaman
2.1
Stratigrafi Regional daerah penelitian (Silitonga, 2003) .............
6
3.1
Klasifikasi indeks tingkat kerapatan sungai .................................
24
4.1
Luas, panjang, dan lebar Sub DAS Cikeruh orde 1 ......................
33
4.2
Luas, panjang, dan lebar Sub DAS Cikeruh orde 2 ......................
37
4.3
Luas, panjang, dan lebar Sub DAS Cikeruh orde 3 ......................
38
4.4
Luas, panjang, dan lebar Sub DAS Cikeruh orde 4 ......................
39
4.5
Bentuk sub DAS dan Rasio kebundaran dari sepuluh DAS
terbesar di DAS Cikeruh ...............................................................
4.6
41
Orde, panjang, jumlah segmen, dan rasio cabang sungai DAS
Cikeruh..........................................................................................
43
4.7
Rasio cabang sungai sepuluh sub DAS terbesar di DAS Cikeruh
44
4.8
Nilai kerapatan sungai pada sub DAS di DAS Cikeruh ...............
45
82
xiv
Halaman
KATA PENGANTAR .................................................................................
iv
ABSTRAK ....................................................................................................
vi
ABSTRACT ...................................................................................................
vii
DAFTAR ISI ................................................................................................
viii
DAFTAR GAMBAR ...................................................................................
xii
DAFTAR TABEL ........................................................................................
xiv
BAB I
BAB II
PENDAHULUAN .......................................................................
1
1.1
Latar Belakang .........................................................
1
1.2
Identifikasi Masalah .................................................
2
1.3
Maksud dan Tujuan ....................................................
2
1.4
Lokasi Daerah Penelitian ...........................................
3
TNJAUAN PUSTAKA ................................................................
4
2.1 Fisiografi Regional ................................................................
4
2.2 Stratigrafi Regional ...............................................................
5
2.3 Morfometri DAS ...................................................................
7
2.3.1 Pola Aliran Sungai .........................................................
7
2.3.2 Luas, Panjang dan Lebar DAS .....................................
8
2.3.3 Bentuk DAS dan Rasio Kebundaran ............................
8
2.3.4 Orde dan Tingkat Percabangan Sungai ........................
9
2.3.5 Kerapatan Pengaliran Sungai .......................................
10
2.4 Aspek Hipsometri ..................................................................
10
2.4.1 Nilai Ketinggian Daerah Tiap n Meter (h) ...................
11
2.4.2 Nilai Ketinggian Daerah Maksimum (H) .....................
11
2.4.3 Nilai Luas Daerah Tiap ketinggian n Meter (a) .......
12
2.4.4 Nilai Luas Daerah Maksimum (A) ..............................
12
2.4.5 Stadium Erosi................................................................
12
2.4.5.1 Stadium Erosi Muda............................................
13
viii
2.4.5.2 Stadium Erosi Menengah.....................................
13
2.4.5.3 Stadium Erosi Tua..............................................
14
BAB III METODE PENELITIAN .............................................................
15
3.1 Objek Penelitian ....................................................................
15
3.2 Alat dan Bahan Penelitian .....................................................
15
3.3 Tahapan Penelitian ................................................................
16
3.3.1 Tahap Persiapan ............................................................
16
3.3.2 Tahap Pengumpulan Data .............................................
17
3.3.3 Tahap Pengolahan dan Analisis Data ...........................
17
3.3.3.1 Analisis Karakteristik Morfometri ...................
17
3.3.3.1.1 Pola Aliran Sungai ...........................
18
3.3.3.1.2 Luas, Panjang, Lebar DAS ..............
20
3.3.3.1.3 Bentuk dan Rasio Kebundaran DAS
21
3.3.3.1.4 Rasio Cabang Sungai .......................
22
3.3.3.1.5 Kerapatan Sungai .............................
23
3.3.3.2 Analisis Variabel Hipsometri ............................
24
3.3.3.2.1 Nilai Ketinggian Daerah Tiap 25 MeTer (h) ...............................................
25
3.3.3.2.2 Nilai Ketinggian Daerah Maksimum (H) 25
3.3.3.2.3 Nilai Luas Daerah Tiap Ketinggian 25
Meter (a) ............................................
25
3.3.3.2.4 Nilai Luas Daerah Maksimum (A) ....
26
3.3.3.2.5 Penentuan Stadium Erosi ...................
27
3.3.4 Tahap Penyusunan Laporan ..........................................
28
BAB IV HASIL DAN PEMBAHASAN ....................................................
30
4.1 Morfometri DAS Cikeruh .....................................................
30
4.1.1 Pola Aliran Sungai ........................................................
31
4.1.2 Luas, Panjang, Lebar DAS ...........................................
32
4.1.3 Bentuk DAS dan Rasio Kebundaran ............................
41
4.1.4 Rasio Cabang Sungai ...................................................
42
4.1.5 Kerapatan Sungai .........................................................
45
ix
4.2 Analisis Variabel Hipsometri .................................................
49
4.2.1 DAS Cikeruh ................................................................
49
4.2.2 Sub DAS Orde 4 ...........................................................
51
4.2.3 Sub DAS Orde 3 ...........................................................
55
4.2.4 Sub DAS Orde 2 ...........................................................
65
4.3 Respon Variabel Hipsometri Terhadap Variasi Litologi .......
71
KESIMPULAN ............................................................................
74
DAFTAR PUSTAKA ...................................................................................
76
BAB V
LAMPIRAN 1 Peta Sebaran Sub DAS Orde 1 Cikeruh
LAMPIRAN 2 Peta Sebaran Sub DAS Orde 2 Cikeruh
LAMPIRAN 3 Peta Sebaran Sub DAS Orde 3 Cikeruh
LAMPIRAN 4 Peta Sebaran Sub DAS Orde 4 Cikeruh
LAMPIRAN 5 Peta Hipsometri Interval 25 m
LAMPIRAN 6 Hasil Perhitungan Variabel Morfometri
LAMPIRAN 7 Hasil Perhitungan Variabel Hipsometri
x
DAFTAR GAMBAR
Gambar
Halaman
1.1
Lokasi Daerah Penelitian .............................................................
4
2.1
Pembagian fisiografi Jawa Barat (Van Bemmelen, 1949) ...........
5
2.2
Peta Geologi Daerah Penelitian (Silitonga, 2003) ........................
6
2.3
Berbagai macam bentuk DAS; A. Bentuk DAS bulu burung; B.
bentuk DAS radial; C. Bentuk DAS paralel (Ramdan, 2006)…...
9
2.4
Penentuan orde sungai menurut Strahler ......................................
10
2.5
Kurva hipsometri stadium erosi muda ..........................................
13
2.6
Kurva hipsometri stadium erosi menengah...................................
14
2.7
Kurva hipsometri stadium erosi tua ..............................................
14
3.1
Pola pengaliran sungai menurut Howard (1967); A. Pola
pengaliran dasar; B - C. Pola pengaliran modifikasi ...................
3.2
20
Berbagai macam bentuk DAS (Ramdan, 2006); A. Bentuk DAS bulu
burung; B. Bentuk DAS radial; C. Bentuk DAS paralel ......................
21
3.3
Penentuan orde sungai Metode Strahler .............................................
23
3.4
Ilustrasi Perhitungan Kurva Hipsometri (Strahler,1952) ....................
26
3.5
Kurva Hipsometri Muda (A); Menengah (B); dan Tua (C) (Strahler,
1952)…………………………………………………………….
27
3.6
Bagan alir penelitian ....................................................................
29
4. 1
Morfologi DAS Cikeruh ……………………...............................
31
4.2
Pola Pengaliran Daerah Penelitian ...............................................
32
xi
4.3
Sebaran Sub DAS Orde 1 Pada DAS Cikeruh .............................
36
4.4
Sebaran Sub DAS Orde 2 Pada DAS Cikeruh ..............................
38
4.5
Sebaran Sub DAS Orde 3 Pada DAS Cikeruh ..............................
39
4.6
Sebaran Sub DAS Orde 4 Pada DAS Cikeruh ..............................
40
4.7
Interval Hipsometri DAS Cikeruh ................................................
49
4.8
Kurva Hipsometri DAS Cikeruh...................................................
50
4.9
Interval Hipsometri Sub DAS Orde 4 D1 .....................................
51
4.10
Kurva Hipsometri Sub DAS Orde 4 D1 .......................................
51
4.11
Interval Hipsometri Sub DAS Orde 4 D2 .....................................
52
4.12
Kurva Hipsometri Sub DAS Orde 4 D2 .......................................
53
4.13
Interval Hipsometri Sub DAS Orde 4 D3 .....................................
53
4.14
Kurva Hipsometri Sub DAS Orde 4 D3 .......................................
54
4.15
Interval Hipsometri Sub DAS Orde 3 C1 .....................................
55
4.16
Kurva Hipsometri Sub DAS Orde 3 C1........................................
55
4.17
Interval Hipsometri Sub DAS Orde 3 C2 .....................................
56
4.18
Kurva Hipsometri Sub DAS Orde 3 C2 ........................................
57
4.19
Interval Hipsometri Sub DAS Orde 3 C3 .....................................
57
4.20
Kurva Hipsometri Sub DAS Orde 3 C3........................................
58
4.21
Interval Hipsometri Sub DAS Orde 3 C4 .....................................
59
4.22
Kurva Hipsometri Sub DAS Orde 3 C4........................................
59
4.23
Interval Hipsometri Sub DAS Orde 3 C5 .....................................
60
4.24
Kurva Hipsometri Sub DAS Orde 3 C5 ........................................
61
4.25
Interval Hipsometri Sub DAS Orde 3 C6 .....................................
62
4.26
Kurva Hipsometri Sub DAS Orde 3 C6........................................
62
xii
4.27
Interval Hipsometri Sub DAS Orde 3 C7 .....................................
63
4.28
Kurva Hipsometri Sub DAS Orde 3 C7........................................
64
4.29
Interval Hipsometri Sub DAS Orde 2 B6 .....................................
65
4.30
Kurva Hipsometri Sub DAS Orde 2 B6 ........................................
65
4.31
Interval Hipsometri Sub DAS Orde 2 B18 ...................................
66
4.32
Kurva Hipsometri Sub DAS Orde 2 B18 ......................................
67
4.33
Interval Hipsometri Sub DAS Orde 2 B19 ...................................
67
4.34
Kurva Hipsometri Sub DAS Orde 2 B19 ......................................
68
4.35
Interval Hipsometri Sub DAS Orde 2 B20 ...................................
69
4.36
Kurva Hipsometri Sub DAS Orde 2 B20 ......................................
69
4.37
Interval Hipsometri Sub DAS Orde 2 B24 ...................................
70
4.38
Kurva Hipsometri Sub DAS Orde 2 B24 ......................................
71
4.39
Perbandingan Kurva Hipsometri pada Sub DAS Orde 2 Beserta
Nilai Dd .........................................................................................
xiii
72
DAFTAR TABEL
Tabel
Halaman
2.1
Stratigrafi Regional daerah penelitian (Silitonga, 2003) .............
6
3.1
Klasifikasi indeks tingkat kerapatan sungai .................................
24
4.1
Luas, panjang, dan lebar Sub DAS Cikeruh orde 1 ......................
33
4.2
Luas, panjang, dan lebar Sub DAS Cikeruh orde 2 ......................
37
4.3
Luas, panjang, dan lebar Sub DAS Cikeruh orde 3 ......................
38
4.4
Luas, panjang, dan lebar Sub DAS Cikeruh orde 4 ......................
39
4.5
Bentuk sub DAS dan Rasio kebundaran dari sepuluh DAS
terbesar di DAS Cikeruh ...............................................................
4.6
41
Orde, panjang, jumlah segmen, dan rasio cabang sungai DAS
Cikeruh..........................................................................................
43
4.7
Rasio cabang sungai sepuluh sub DAS terbesar di DAS Cikeruh
44
4.8
Nilai kerapatan sungai pada sub DAS di DAS Cikeruh ...............
45
82
xiv