DR. IR. ERIZAL, MAGR. DEPARTEMEN TEKNIK SIPIL DAN LINGKUNGAN FAKULTAS TEKNOLOGI PERTANIAN IPB
Why “klasifikasi tanah” ??? Nampak secara nyata bahwa tanah di permukaan bumi kita ini sangat beragam (warna, tekstur, struktur dll). Maka... Untuk membedakan tanah-tanah tersebut diperlukan klasifikasi tanah.
Tujuan Klasifikasi Tanah 1. Mengorganisasi atau menata tanah 2. Mengetahui hubungan individu tanah 3. Memudahkan mengingat sifat-sifat tanah 4. Mengelompokkan tanah untuk : - menaksir sifat - penelitian - mengetahui lahan2 yg baik
Klasifikasi Tanah ada 2: Klasifikasi Alami Didasarkan atas sifat tanah yg dimiliki tanpa menghubungkan dg tujuan penggunaan tanah tersebut.
Klasifikasi Teknis Didasarkan pada sifat-sifat tanah yang mempengaruhi kemampuan tanah untuk penggunaanpenggunaan tertentu.
• Selanjutnya........... ....dalam pengertian sehari-hari, Klasifikasi Tanah Alami dikenal dengan.........
KLASIFIKASI TANAH
Sistem Klasifikasi Tanah yang ideal mampu mengelompokkan tanah dalam satu kelas yang.... 1.
Isogenus Tanah yg mpy genesis sama 2. Isomorf Tanah yg mpy kenampakan yg sama 3. Isofungsi Tanah yg mpy fungsi sama dlm lingk. 4. Isotropik Tanah yg mpy lokasi yg sama
Macam “Sistem Klasifikasi Tanah” 1. Pusat Penelitian Tanah Bogor 2. FAO/UNESCO (1974) 3. USDA = Soil Taxonomy (USDA, 1975; Soil Survey Satff, 1999; 2003).
Sistem Klasifikasi Tanah Pusat Penelitian Tanah Bogor Sistem Klasifikasi Tanah yang digunakan oleh Pusat Penelitian Tanah Bogor adalah sistem yang dikembangkan oleh DudalSoepraptohardjo (1957), sistem tersebut sebenarnya mirip dengan sistem yang berkembang di AS oleh Baldwin, Kellogdan Thorp (1938) : Thorn dan Smith (1949) dengan beberapa modifikasi.
Perkembangan selanjutnya... Sistem menurut Dudal-Soepraptohardjo (1957), terus disempurnakan sesuai dengan Sistem AS yg baru(Soil Taxonomy, 1975) dan dari USDA terutama dalam : Definisi jenis-jenis tanah (great group) Macam tanah (subgroup)
Sistem Dudol-Soepraptohardjo (1957-1961)
Modifikasi 1978/1982 (PPT)
FAO/UENESCO (1974)
USDA Soil Taxonomy (1975 – 1990)
1.
Tanah Aluvial
Tanah aluvial
Fluvisol
-
2.
Andosol
Andosol
Andosol
Andisol
3.
Brown Forest Soil
Kambisol
Cambisol
Inceptisol
4.
Grumusol
Grumusol
Vertisol
Vertisol
5.
Latosol
-
-
-
6.
Litosol
Litosol
Litosol
Entisol (lithic Subgrup)
7.
Mediteran
Mediteran
Luvisol
Alfisol/inceptisol
8.
Organosol
Organosol
Histosol
Histosol
9.
Podsol
Podsol
Podsol
Spodosol
10. PodsolikMerah Kuning
Podsolik
Acrisol
Ultisol
11. Podsolik Coklat
Kambisol
Cambisol
Inceptisol
12. Podsolik Coklat kelabu
Podsolik
Acrisol
Ultisol
13. Regosol
Regosol
Regosol
Entisol/Inceptisol
14. Renzina
Renzina
Renzina
Rendoll
Kambisol Latosol Lateritik
Cambisol Nitosol Ferralsol
Entisol Inceptisol
Inceptisol Ultisol Oxisol
Sistem Klasifikasi Tanah USDA (1975, 1999, 2003) ORDO (ORDER) SUBORDO (SUB-ORDER)
GRUP (GREAT GROUP)
SUB-GRUP (SUBGROUP)
FAMILY
SERI
Nama Ordo
Akhiran Untuk Kategori Lain
Arti Asal Kata
Alfisol
ALF
Dari Al-Fe
Andisol
AND
Ando, tanah hitam
Aridisol
ID
Aridus, sangat kering
Entisol
ENT
Dari Recent
Gelisol
EL
Gelare, membeku
Histosol
IST
Histos, jaringan
Inceptisol
EPT
Inceptum, permulaan
Mollisol
OLL
Mollis, lunak
Oxisol
OX
Oxide, oksida
Spodosol
OD
Spodos, abu
Ultisol
ULT
Ultimus, akhir
Vertisol
ERT
Verto, berubah
ORDO Ordo tanah dibedakan berdasarkan ada tidaknya horison penciri serta jenis (sifat) dari horison penciri tersebut. Contoh : Horison penciri : argilik,KB >35 % = ordo Alfisol Horison penciri : argilik,KB <35% = ordo Ultisol
SUBORDO Subordo tanah dibedakan perbedaan genetik tanah, misal : ada tidaknya sifat2 tanah yg berhub.dg : air, kelembaban, bi, vegetasi. Khusus Histosol, sub ordo dibedakan
tk.pelapukan b.o. nya (febris, hemis, safris)
Contoh : Subordo : Udult berasal dari Udus/udic = tanah yg pernah lembab, singkatannya Ud. Ud ditambah dg ordo Ultisol (disingkat Ult), sehingga sub ordo = Udult
GRUP (GREAT GROUP) Dibedakan berdasarkan perbedaan (1)jenis, (2) tk.perkembg, (3) susunan horiz, (4) KB, (5) kelembaban, (6) ada tidaknya lapisan2 penciri lain : plinthite, fragipan, duripan Contoh : Grup Fragiudult Lapisan tsbt memiliki lapisan padas Fragipan mk disingkat fragi. Shg kata fragi ditambah pd Sub ordo Udult , jadi... Fragiudult.
SUBGRUP Dibedakan berdsr : (1) sifat inti grup & diberi nama Typic, (2) sifat2 tanah peralihan ke grup lain, sub ordo lain atau ordo lain. Contoh : Subgrup : Aquic Fragiudult tanah tsbt memiliki sifa peralihan ke sub ordo Aquult, krn kadang2 adanya pgrh air, shg tmsk sub grup Aquic
Family
Dibedakan berdsr sifat2 yg penting u/ pertanian atau teknik, (1) sebaran butir, (2) mineral liat, (3) regim temperatur pd kedlmn 50 cm. Contoh : Aquic Fragiudult, berliat halus,
kaolonit, isohipertermik.
Penciri famili, susunan butir berliat halus & jenis liat adl kaolinit, regim temperatur isohipertemik (> 22° C dg perbedaan suhu tnh musim panas & dingin <5°C)
Seri Tanah Seri tanah menunjukkan nama lokasi tanah tersebut pertama kali ditemukan. Contoh : Aquic Fragiudult, berliat halus, kaolonit, isohipertermik,Sitiung Sitiung : lokasi pertama kali ditemukan tanah pada kategori seri tersebut.
HORIZON PENCIRI 1. Epipedon Horizon bagian permukaan (≠ horizon A), mungkin lebih lebih tipis dari horizon A, tetapi mungkin juga meliputi horizon B. 2. Endopedon Horizon dibawah permukaan
ALFISOL • The central concept of Alfisols is that of soils that have an argillic, a kandic, or a natric horizon and a base saturation of 35% or greater. • They typically have an ochric epipedon, but may have an umbric epipedon. They may also have a petrocalcic horizon, a fragipan or a duripan.
ANDISOLS • The central concept of Andisols is that of soils dominated by short-rangeorder minerals. • They include weakly weathered soils with much volcanic glass as well as more strongly weathered soils. • Hence the content of volcanic glass is one of the characteristics used in defining andic soil properties
ARIDISOL Aridisols is that of soils that are too dry for mesophytic plants to grow. They have either: (1) an aridic moisture regime and an ochric or anthropic epipedon and one or more of the following with an upper boundry within 100 cm of the soil surface: a calcic, cambic, gypsic, natric, petrocalcic petrogypsic, or a salic horizon or a duripan or an argillic horizon, or (2)A salic horizon and saturation with water within 100 cm of the soil surface for one month or more in normal years.
ENTISOLS • The central concept of Entisols is that of soils that have little or no evidence of development of pedogenic horizons. • Many Entisols have an ochric epipedon and a few have an anthropic epipedon. Many are sandy or very shallow.
GELISOLS • The central concept of Gelisols is that of soils that have permafrost within 100 cm of the soil surface and/or have gelic materials within 100 cm of the soil surface and have permafrost within 200 cm. • Gelic materials are mineral or organic soil materials that have evidence of cryoturbation (frost churning) and/or ice segeration in the active layer (seasonal thaw layer) and/or the upper part of the permafrost.
HISTOSOLS • The central concept of Histosols is that of soils that are dominantly organic. They are mostly soils that are commonly called bogs, moors, or peats and mucks. • A soil is classified as Histosols if it does not have permafrost and is dominated by organic soil materials.
INCEPTISOLS • The central concept of Inceptisols is that of soils of humid and subhumid regions that have altered horizons that have lost bases or iron and aluminum but retain some weatherable minerals. They do not have an illuvial horizon enriched with either silicate clay or with an amorphous mixture of aluminum and organic carbon. • The Inceptisols may have many kinds of diagnostic horizons, but argillic, natric kandic, spodic and oxic horizons are excluded.
MOLLISOLS • The central concept of Mollisols is that of soils that have a dark colored surface horizon and are base rich. Nearly all have a mollic epipedon. • Many also have an argillic or natric horizon or a calcic horizon. A few have an albic horizon. Some also have a duripan or a petrocalic horizon.
OXISOLS • The central concept of Oxisols is that of soils of the tropical and subtropical regions. They have gentle slopes on surfaces of great age. They are mixtures of quartz, kaolin, free oxides, and organic matter. • For the most part they are nearly featureless soils without clearly marked horizons. Differences in properties with depth are so gradual that horizon boundaries are generally arbitrary.
SPODOSOLS • The central concept of Spodosols is that of soils in which amorphous mixtures of organic matter and aluminum, with or without iron, have accumulated. In undisrurbed soils there is normally an overlying eluvial horizon, generally gray to light gray in color, that has the color of more or less uncoated quartz. • Most Spodosols have little silicate clay. The particle-size class is mostly sandy, sandy-skeletal, coarse-loamy, loamy, loamyskeletal, or coarse-silty.
ULTISOLS • The central concept of Ultisols is that of soils that have a horizon that contains an appreciable amount of translocated silicate clay (an argillic or kandic horizon) and few bases (base saturation less than 35 percent). • Base saturation in most Ultisols decreases with depth.
VERTISOLS • The central concept of Vertisols is that of soils that have a high content of expending clay and that have at some time of the year deep wide cracks. • They shrink when drying and swell when they become wetter.
