DASAR ILMU TA AH Ma M t a e t ri r 10: : K l K as a ifika k s a i Ta T n a a n h a

(1)

DASAR ILMU TAAH

Materi 10: Klasifikasi Tanah

(2)

KLASIFIKASI TANAH

(3)

Klasifikasi Tanah

Usaha membeda-bedakan

mengelompokkan tanah berdasarkan

sifat-sifatnya

Tujuan

mengetahui sifat dan ciri tanah pada

masing-masing kelompok tanah (kelas tanah)

sehingga memudahkan pengguna tanah

untuk mengelola tanah tersebut agar dapat

berproduksi secara optimal

(4)

Alami/taksonomi:berdasarkan

sifat2 _{alami tanah tanpa dihub. dgn} pengunaannya

- Taksonomi Tanah (USDA)

Teknikal: berdasarkan tujuan

Klasifikasi

Teknikal: berdasarkan tujuan khusus dgn memilih ciri2 _{ttt yg pgrhi}

kemampuan dan penggunaannya

- - Klasifikasi Kemampuan Lahan USDA

(5)

General Principles of Natural Classification Systems:

• The system should express general or universal

relationships that exist in nature. One should be able to understand, remember, generalize, or predict from the information obtained.

• The scheme should be based on characteristics or attributes of things classified as related to their attributes of things classified as related to their

genesis. It should place similar things together on the basis of their properties.

• It is technically impossible to use all properties of the items being classified. Existing knowledge must be used to determine which properties are most

(6)

Why Classify Soils?

• Organize knowledge to enable investigation

and communication (structure/organization)

• Provide framework for establishing

relationships among soils and their

environment (scientific)

• Establish groupings for interpretations

(utilitarian)

– Optimal use

– Hazard/limitation/remediation assessment – Potential productivity

– Framework for technology transfer/information dissemination

(7)

(8)

Klasifikasi Tanah di Indonesia

Sejak th 1988 hanya gunakan

sistem Taksonomi Tanah.

Sebelum 1988 ada 3

:

--

Pusat Penelitian Tanah (PPT)

--

FAO/UNESCO

(9)

Taksonomi Tanah (USDA)

dikembangkan oleh Soil Survey Staff

(USDA), tahun 1975

Terus direvisi

2ed, 1999

ada 6 kategori yaitu

Order, Suborder,

ada 6 kategori yaitu

Order, Suborder,

Great group, Subgroup, Family

dan

(10)

Categories in ST:

OrderOrder –– key soil properties resulting from major soilkey soil properties resulting from major

soil--forming processes (epipedons, subsurface horizons, forming processes (epipedons, subsurface horizons, materials, characteristics)

materials, characteristics)

SuborderSuborder –– key soil properties that are major controls on key soil properties that are major controls on

soil

soil--forming processes, e.g., soil climate (most orders); forming processes, e.g., soil climate (most orders); kinds of salts (Aridisols); kinds of soil parent materials kinds of salts (Aridisols); kinds of soil parent materials

(Entisols); degree of decomposition (Histosols); presence (Entisols); degree of decomposition (Histosols); presence or absence of cryoturbation (Gelisols)

or absence of cryoturbation (Gelisols) or absence of cryoturbation (Gelisols) or absence of cryoturbation (Gelisols)

Great GroupGreat Group –– key soil properties that are additional key soil properties that are additional

controls on soil genesis (diagnostic horizons) controls on soil genesis (diagnostic horizons)

SubgroupSubgroup –– central concept (Typic), intergrades, central concept (Typic), intergrades,

extragrades extragrades

FamilyFamily –– properties important to plant growth (texture, properties important to plant growth (texture,

mineralogy, soil temperature regime, etc.) mineralogy, soil temperature regime, etc.)

(11)

Kategori

Kategori NamaNama KategoriKategori NamaNama

Phylum

Phylum PteridophytaPteridophyta OrderOrder AlfisolAlfisol Kelas

Kelas AngiospermaeAngiospermae SubSub--orderorder UdalfUdalf Sub

Sub--kelaskelas DicotyledoneaeDicotyledoneae GreatgroupGreatgroup HapludalfHapludalf Order

Order RosalesRosales SubSub--groupgroup AquicAquic HapludalfHapludalf Order

Order RosalesRosales SubSub--groupgroup AquicAquic HapludalfHapludalf Family

Family LeguminoseaeLeguminoseae FamilyFamily Aquic Hapludalf, berlempung Aquic Hapludalf, berlempung halus, Campuran, Aktif,

halus, Campuran, Aktif, Isohipertermik

Isohipertermik Genus

Genus TrifoliumTrifolium SeriSeri LapeLape Species

(12)

Differentiating Characteristics in ST

::

Diagnostic epipedons

Diagnostic subsurface horizons

Other diagnostic soil characteristics

Soil moisture and temperature

regimes

(13)

1. Epipedon

horison penciri yg terbentuk di

permukaan tanah.

tidak sinonim dg horizon A

dapat mencakup sebagian

horizon B.

(14)

EPIPEDON

Surface horizons

Influenced strongly by

biochemical and

geochemical processes

Correspond with A, E, and

sometimes upper B horizons

(15)

EPIPEDON

HistikHistik: : Bahan organik (BO) tinggi (>75%), tebal 20Bahan organik (BO) tinggi (>75%), tebal 20--40cm.40cm.

MollikMollik: : BO >1%, warna gelap dg value dan kroma <3 BO >1%, warna gelap dg value dan kroma <3

(lembab) dan value < 5 (kering), tebal >18cm, KB (lembab) dan value < 5 (kering), tebal >18cm, KB >50%.

>50%.

MelanikMelanik: : mirip Mollik,mirip Mollik, tetapitetapi miliki sifat tanah andikmiliki sifat tanah andik

UmbrikUmbrik: : seperti molik seperti molik tetapitetapi KB <50%.KB <50%.

AnthropikAnthropik: : seperti molik, seperti molik, tetapitetapi mengandung >1500 ppm P2O5 mengandung >1500 ppm P2O5

larut dalam 1% as sitrat. larut dalam 1% as sitrat.

OchrikOchrik: : warna terang (value dan kroma lembab >3), BO warna terang (value dan kroma lembab >3), BO

<1% atau keras

<1% atau keras--sangat keras dan masif.sangat keras dan masif.

PlaggenPlaggen: : horizon buatan, akibat penggunaan pupuk kandang yg horizon buatan, akibat penggunaan pupuk kandang yg

terus menerus, tebal >50cm, berwarna hitam. terus menerus, tebal >50cm, berwarna hitam.

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Horison Penciri Bawah

AgrikAgrik: : horizon iluviasi yg terbentuk krn pengaruh horizon iluviasi yg terbentuk krn pengaruh

pengolahan tanah shg terjadi akumulasi sejumlah pengolahan tanah shg terjadi akumulasi sejumlah debu, liat, dan

debu, liat, dan humus.humus.

AlbikAlbik: : horison berwarna pucat (E) dg value lembab >5.horison berwarna pucat (E) dg value lembab >5.

ArgillikArgillik: : horison penimbunan liat; minimal mengandung horison penimbunan liat; minimal mengandung liat liat

>1.2 kali lebih banyak daripada kandungan liat di >1.2 kali lebih banyak daripada kandungan liat di >1.2 kali lebih banyak daripada kandungan liat di >1.2 kali lebih banyak daripada kandungan liat di atasnya.Terdapat selaput liat.

atasnya.Terdapat selaput liat.

KalsikKalsik: : horizon yg mengandung karbonat sekunder horizon yg mengandung karbonat sekunder

(CaCO

(CaCO₃₃ atau MgCOatau MgCO₃₃) tinggi, tebal >15cm.) tinggi, tebal >15cm.

PetrokalsikPetrokalsik:: horizon kalsik yang mengeras.horizon kalsik yang mengeras.

KambikKambik: : indikasi lemah adanya argillik atau spodik, tapi tidak indikasi lemah adanya argillik atau spodik, tapi tidak

memenuhi syarat kedua horizon tersebut. memenuhi syarat kedua horizon tersebut.

(17)

Horison Penciri Bawah (lanjutan)

GipsikGipsik : : banyak mengandung gipsum (CaSO4) sekunder.banyak mengandung gipsum (CaSO4) sekunder.

PetrogipsikPetrogipsik:: horizon gipsik yg mengeras.horizon gipsik yg mengeras.

NatrikNatrik : : horizon argillik yg banyak mengandung Nahorizon argillik yg banyak mengandung Na

OksikOksik : : horizon bertekstur agak kasar, KTK <16 me/100g liat, horizon bertekstur agak kasar, KTK <16 me/100g liat,

tebal >30cm. tebal >30cm.

SalikSalik: : banyak mengandung garam sekunder mudah larut, banyak mengandung garam sekunder mudah larut,

tebal >15cm. tebal >15cm.

SombrikSombrik : : seperti umbrik, gelap, terjadi iluviasi humus tanpa Al, seperti umbrik, gelap, terjadi iluviasi humus tanpa Al,

tidak terletak di bawah horizon albik. tidak terletak di bawah horizon albik.

SpodikSpodik : : horizon iluviasi seskuioksida bebas dan BO.horizon iluviasi seskuioksida bebas dan BO.

SulfurikSulfurik : : horizon yg mengandung sulfat, pH ,3.5, tdpt karatan horizon yg mengandung sulfat, pH ,3.5, tdpt karatan

jarosit. jarosit.

(18)

Kategori

Kategori NamaNama KategoriKategori NamaNama

Phylum

Phylum PteridophytaPteridophyta OrderOrder AlfisolAlfisol Kelas

Kelas AngiospermaeAngiospermae SubSub--orderorder UdalfUdalf Sub

Sub--kelaskelas DicotyledoneaeDicotyledoneae GreatgroupGreatgroup HapludalfHapludalf

TAKSOOMI TUMBUHA vs TAKSOOMI TAAH

Order

Order RosalesRosales SubSub--groupgroup AquicAquic HapludalfHapludalf Family

Family LeguminoseaeLeguminoseae FamilyFamily Aquic Hapludalf, berlempung Aquic Hapludalf, berlempung halus, Campuran, Aktif,

halus, Campuran, Aktif, Isohipertermik

Isohipertermik Genus

Genus TrifoliumTrifolium SeriSeri LapeLape Species

(19)

“

Soil Taxonomy

"

Degree of Weathering and B Horizon Development Degree of Weathering and B Horizon Development Little

Little SlightSlight ModerateModerate LargeLarge ExtremeExtreme

Entisols

Entisols AridisolsAridisols Inceptisols

Inceptisols AlfisolsAlfisols

Spodosols

Spodosols UltisolsUltisols Mollisols

Mollisols OxisolsOxisols Mollisols

Mollisols OxisolsOxisols

Soils Defined by Special Constituent Materials Soils Defined by Special Constituent Materials

Andisols

Andisols Volcanic AshVolcanic Ash Histosols

Histosols Peat, Organic MatterPeat, Organic Matter Vertisols

Vertisols “Self“Self--Mixing” Clay SoilsMixing” Clay Soils Gelisols

(20)

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.

(21)

ANDISOLS

The central concept of The central concept of

Andisols is that of soils Andisols is that of soils dominated by short

dominated by short--range range--order minerals.

order minerals.

They include weakly They include weakly

weathered soils with much weathered soils with much weathered soils with much weathered soils with much

volcanic glass as well as more volcanic glass as well as more strongly weathered soils.

strongly weathered soils.

Hence the content of volcanic Hence the content of volcanic

glass is one of the glass is one of the

characteristics used in defining characteristics used in defining andic soil properties

(22)

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 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.

(23)

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.

(24)

GELISOLS

The central concept of Gelisols is The central concept of Gelisols is

that of soils that have permafrost that of soils that have permafrost within 100 cm of the soil surface within 100 cm of the soil surface and/or have gelic materials within and/or have gelic materials within 100 cm of the soil surface and have 100 cm of the soil surface and have permafrost within 200 cm.

permafrost within 200 cm. permafrost within 200 cm. permafrost within 200 cm.

Gelic materials are mineral or Gelic materials are mineral or

organic soil materials that have organic soil materials that have evidence of cryoturbation (frost evidence of cryoturbation (frost churning) and/or ice segeration in churning) and/or ice segeration in the active layer (seasonal thaw the active layer (seasonal thaw layer) and/or the upper part of the layer) and/or the upper part of the permafrost.

(25)

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.

(26)

INCEPTISOLS

The central concept of The central concept of

Inceptisols is that of soils of Inceptisols is that of soils of humid and subhumid regions humid and subhumid regions that have altered horizons that that have altered horizons that have lost bases or iron and

have lost bases or iron and aluminum but retain some aluminum but retain some

weatherable minerals. They do weatherable minerals. They do not have an illuvial horizon

not have an illuvial horizon not have an illuvial horizon not have an illuvial horizon

enriched with either silicate clay enriched with either silicate clay or with an amorphous mixture or with an amorphous mixture of aluminum and organic

of aluminum and organic carbon.

carbon.

The Inceptisols may have many The Inceptisols may have many

kinds of diagnostic horizons, but kinds of diagnostic horizons, but argillic, natric kandic, spodic

argillic, natric kandic, spodic

and oxic horizons are excluded. and oxic horizons are excluded.

(27)

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

(28)

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.

(29)

SPODOSOLS

The central concept of Spodosols The central concept of Spodosols

is that of soils in which amorphous is that of soils in which amorphous mixtures of organic matter and

mixtures of organic matter and aluminum, with or without iron, aluminum, with or without iron, have accumulated. In undisrurbed have accumulated. In undisrurbed soils there is normally an overlying soils there is normally an overlying eluvial horizon, generally gray to eluvial horizon, generally gray to eluvial horizon, generally gray to eluvial horizon, generally gray to light gray in color, that has the color light gray in color, that has the color of more or less uncoated quartz. of more or less uncoated quartz.