BAHAN KAJIAN MK. DASAR ILMU TANAH. Smno.jursntnh.fpub.febr2013

Foto: smno.kampus.ub.janu2013 BAHAN KAJIAN MK. DASAR ILMU TANAH. Smno.jursntnh.fpub.febr2013

DESKRIPSI TANAH Soil is a natural body consisting of layers (soil horizons) that are primarily composed of minerals which differ from their parent materials in their texture, structure, consistency, color, chemical, biological and other characteristics. It is the unconsolidated or loose covering of fine rock particles that covers the surface of the earth. Tanah merupakan hasil akhir dari pengaruh iklim (temperature, precipitation), relief (slope), organisme (flora dan fauna), bahan induk (mineral-mineral), dan waktu.

DIUNDUH DARI: http://en.wikipedia.org/wiki/Soil……. 13/2/2013

DESKRIPSI TANAH Pedology (from Greek: πέδον, pedon, "soil"; and λόγος, logos, "study") is the study of soils in their natural environment. It is one of two main branches of soil science, the other being edaphology. Pedology mengkaji pedogenesis, morfologi tanah, dan klasifikasi tanah; sedangkan edaphology mengkaji cara-cara bagaimana tanah mempengaruhi tumbuhan, fungi, dan organisme lainnya. Soil is not only a support for vegetation, but it is also the zone beneath our feet (the pedosphere) of numerous interactions between climate (water, air, temperature), soil life (micro-organisms, plants, animals) and its residues, the mineral material of the original and added rock, and its position in the landscape. Selama proses genesisnya, profil tanah mengalami pendalaman dan mengembangkan lapisan-lapisan yang khas, yang disebut 'horizon', sambil menuju keadaan kesetimbangan. DIUNDUH DARI: http://en.wikipedia.org/wiki/Pedology_%28soil_study%29……. 13/2/2013

DESKRIPSI TANAH SOIL MORPHOLOGY is the field observable attributes of the soil within the various soil horizons and the description of the kind and arrangement of the horizons. C.F. Marbut championed reliance on soil morphology instead of on theories of pedogenesis for soil classification because theories of soil genesis are both ephemeral and dynamic. The observable attributes ordinarily described in the field include the composition, form, soil structure and organization of the soil, color of the base soil and features such as mottling, distribution of roots and pores, evidence of translocated materials such as carbonates, iron, manganese, carbon and clay, and the consistence of the soil. The observations are typically performed on a soil profile. A profile is a vertical cut, two dimensional, in the soil and bounds one side of a pedon. The pedon is the smallest three dimensional unit, but not less than 1 meter square on top, that captures the lateral range of variability. DIUNDUH DARI: http://en.wikipedia.org/wiki/Soil_morphology……. 13/2/2013

DESKRIPSI TANAH : HORISON Horison tanah adalah lapisan-lapisan di dalam profil tanah yang posisinya sejajar dnegan permukaan tanah. A soil profile is made up of several horizons and each is distinguished from the horizon above or below by being different in one or more characteristics. These differences include colour, texture, structure, consistence, and coatings.

DIUNDUH DARI: http://soilsdev.waikatoregion.govt.nz/Topic-Describing_Soils/How_To_Recognise_Soil_Horizons/ ……. 16/2/2013

MORFOLOGI TANAH

DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

MORFOLOGI TANAH Berdasarkan pada sifat fisika dan kimiawi :

WARNA TEKSTUR STRUKTUR Density / PorositAS PERGERAKAN AIR Reactivity of mineral and organic colloids KEMASAMAN TANAH & pH


Color

Dark/grayish-black color Orange vs. Gray colors

Texture

Sandy vs. Clayey

Structure Good vs. Poor Structure Density

Porosity, organic matter, compaction

Water

Pore sizes, porosity, water movement, saturation

Reactivity

Cation exchange capacity

Acidity

Plant tolerances, buffering, base saturation DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Factors Affecting Soil Formation

The 5 soil forming factors

Climate Organisms/Vegetation Parent material Topography Time


PENAMAAN / PENGENALAN HORISON TANAH O Horizon

A horizon E horizon

B horizon Horison C

Horison Utama - Master Horizons

Organic matter

Sandy Clays/iron

Parent

1.

O Organik

2.

A Topsoil, Bahan organik, daur-ulang

3.

E Elluviasi

4.

B Berkembang /akumulasi

5.

C Bahan induk tanah

6.

R Batuan dasar


Master Horizons; Horison Utama Enough information? O horizon A horizon

R horizon

E horizon (Elluvial)

C horizon B horizon

B horizon

(Illuvial)


Subordinate Distinctions b – buried horizon – Horison terkubur c – concretions d – root restrictive g – gleying h – illuvial organic matter k – carbonates m – cementation o - oxic p – plowing/disturbance q – secondary silica r – soft bedrock (saprolite) s – illuvial sesquioxides and O.M. t – clay accumulation v – plinthite w – development of color/structure x - fragipan

g – gleying h – illuvial organic matter p – plowing/disturbance t – clay accumulation w – development of color/structure o – oxic - Oksik


Subordinate Distinction h = Akumulasi bahan organik 1. 2. 3. 4. 5.

Akumulasi bahan illuvial kompleks logam-bahan organik Selimut pada pasir dan partikel diskrit h = “humik” Value dan chroma sekitar 3 atau kurang Digunakan dnegan horison utama B (mos. Horison Bh)

Horison Bh “Horison Spodik” DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Subordinate Distinction

p = dibajak/diolah, plowed Horison permukaan yang terganggu (Kultivation, pasture, Kehutanan) Digunakan dengan horison utama A (mis. Horison Ap)

Ap horizon


Pembeda sub-ordinat = Subordinate Distinction

t = akumulasi liat 1. 2. 3. 4.

Translokasi liat atau terbentuk di tempat Selimut atau diskrit Digunakan dnegan horison utama B (mis. Bt) Kalau reduksi, dapat digunakan dengan sub-horison g (Btg)



w = warna atau struktur Perkembangan warna atau struktur secara Non-illuvial “w” = “weak” Biasanya digunakan dnegan horison utama B (mis. Bw)

Bw



o = oxic horizon 1. 2. 3. 4.

Aktivitas liat rendah Sedikit bahan dapat lapuk Struktur batuan sedikit Oksida Fe dan Al

Horison oksik mempunyai: 1. a CEC 7 < 16cmol(+)/kg of clay and an ECEC < 12 cmol(+)/kg of clay which is due to the low activity clay minerals (1:1 clays, Fe and Al oxides, etc) 2. < 10% weatherable minerals in the sand fraction 3. Struktur batuan < 5% DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Subordinate Distinctions g – gleying h – illuvial organic matter p – plowing/disturbance t – clay accumulation w – development of color/structure o – oxic DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

KEJELASAN - DISTINCTNESS

Distinctness describes the ease with which features can be identified. It is often used for mottle colour and surface coatings.

Faint:

Features can only be identified using 10x lens and cannot be positively identified in all places. They are generally thin and their contrast with the adjacent matrix is small.

Distinct:

Features have sufficient colour or texture contrast to be seen without magnification, but may need a lens for positive identification.

Prominent:

Features are conspicuous without magnification and can be readily distinguished from the matrix by sharp colour or texture contract or by their thickness. Some thin features, eg mangans can be prominent. Sumber: http://soilsdev.ew.govt.nz/TopicDescribing_Soils/Distinctness/

Subordinate Distinction

a, e, i Menyatakan derajat dekomposisi bahan organik dalam Horison O Oa – Dekomposisi lanjut (Saprik) Oe – Dekomposisi moderat (Hemik) Oi – Dekomposisi ringan (Fibrik) Saprik – Dekomposisi lanjut, serat tumbuhan sedikit, kandungan air rendah Hemik – Dekomposisi sedang / intermediate Fibrik – dekomposisi ringan, serat-serat masih dapat dikenali


Ikhtisar Horison Utama: O, A, E, B, C, R Simbol Subordinate : g, h, p, t, w and a,e,i Contoh:

Oa, Oe, Oi Bt Bg Btg Bw Ap


Vertical Subdivisions Dicirikan oleh sifat-penciri utama dan/atau subordinat yang serupa, dipisahkan oleh “degree”.

Horison Bt

Bt1 Bt2 Bt3


Horison Transisi Lapisan transisi di antara horison utama.

AE EB BE Ciri Dominan

Ciri Subordinate


Hierarkhi Taksonomi Tanah

Order

12

Suborder

63

Great group

250

Sub group

1400

Family

8000

Series

19,000 DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Kingdom Phylum Class Order Family Genus Species

Unit-unit untuk klasifikasi tanah Pedon – smallest three-dimensional unit that displays the full range of properties characteristic of a given soil. (1-10 m2 of area) - Unit mendasar dari klasifikasi tanah

Polypedon – Sekelompok pedon yang berhubungan erat di lapangan

Soil Series – class of soils world-wide which share a common suite of soil profile properties


Unit-unit Sampel Tanah

Malabar Series


Horison Diagnostik (Horison Penciri) untuk Klasifikasi Tanah

Permukaan Bawahperrmukaan


Diagnostic Surface Horizons Epipedon Mollik Umbrik Ochrik Histik Melanik Plaggen Anthropik

DIUNDUH DARI: http://www.soils.wisc.edu/courses/SS325/organic.htm ……. 16/2/2013

Horison-permukaan Diagnostik = Diagnostic Surface Horizons X = Florida Melanik X

Plaggen

Histik

Mollic X

Umbrik X

Anthropik Okhrik X


Mollic Epipedon Tebal

> 18-25 cm

Warna

Value

< 3.5 lembab

Chroma < 3.5 lembab

C-organik

> 0.6 %

Kejenuhan basa Struktur tanah

> 50 % Berkembang sangat baik

Karbon Organik = Bahan organik x 0.57


EPIPEDON UMBRIK

Memenuhi semua kriteria Epipedon Molik, Kecuali kejenuhan basanya < 50%

Secara kimiawi berbeda dengan Molik


EPIPEDON OKRIK = Ochric Epipedon Terlalu : Tipis Ringan, warna terang Muskin bahan organik

Mollic Umbric

Ochric = Pucat Sangat umum - “Extremely common”


Epipedon Histik

1. Horison organik yg terbentuk di daerah basah 2. Warna hitam hingga coklat gelap 3. Bobot Isi rendah 4. Tebalnya 20-30 cm

Organik =

> 20% - 35% bahan organik. (Jenuh air, kadar liat ) DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Epipedon Melanik 1. Sifatnya serupa dnegan Molik 2. Terbentuk dalam abu vulkanik 3. Ringan, Fluffy Melanic Epipedon: The melanic epipedon is a thick black horizon which contains high concentrations of organic matter, usually associated with short-range-order minerals or aluminium-humus complexes. The intense black color is attributed to the accumulation of organic matter from which "Type A" humic acids are extracted. This organic matter is thought to result from large amounts of gramineous vegetation, and can be distinguished from organic matter formed under forest vegetation by the melanic index. (http://www.soils.wisc.edu/courses/SS325/organic.htm) DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

HORISON ANTHROPIK • Serupa dengan Molik (warna, bahan organik) • Digunakan manusia • Tulang dan kerangka • Air dari aktivitas manusia

Anthropic Epipedon: The requirements for the anthropic epipedon are the same for the mollic, except that P2O5 soluble in 1% citric acid is > 250 ppm. (http://www.soils.wisc.edu/courses/SS325/organic.ht m)


Epipedon Plaggen Dihasilkan oleh penggunaan rabuk jangka panjang (100s tahun) Horison permukaan buatan manusia, tua Tebal > 50 cm

Plaggen Epipedon:

The plaggen epipedon is a cultural surface horizon produced by long continued manuring. Its color depends on the nature of the manure. Commonly it contains artifacts, such as bits of bricks and pottery through out its depth. (http://www.soils.wisc.edu/courses/SS325/organic.htm)


Diagnostic Surface Horizons

Epipedon: Mollic Umbric Ochric Histic Melanic Plaggen Anthropic

Very common “specialized” Human-derived


Akumulasi Bahan ORganik

Akumulasi bahan organik

Histic Mollic, Umbric ochric

waktu Bahan induk

Vegetasi

tmax = 3000 yrs DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Diagnostic Subsurface Horizons Horison-penciri yang lokasinya di bawah-permukaan Pembentukan Translokasi Transformasi

Clays Endopedon (B) Agric Argillic Cambic Kandic Natric Oxic Sombric Spodic

Organic Matter

Oxides

: Akumulasi liat dan humus, akibat pengolahan tanah : Akumulasi liat : "color" atau perkembangannya lemah : Argillik dengan liat seperti-kaolinit : Argillic, nilai ESP tinggi : Pelapukan lanjut : Masam, akumulasi humus, tropis : Masam, daerah dingin, akumulasi humus-sesquioxida DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Subsurface Horizons Formation Translocation Transformation

Bahan organik Warna gelap Logam (Fe, Al)

Liat Smectit

Kaolinit

Oksida Iron Aluminum

Juga: garam, karbonat, sulfida DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013

Diagnostic Subsurface Horizons Horison-penciri yang lokasinya di bawah-permukaan

Albic Argillic Spodic Oxic Kandic Cambic Sombric sulfuric

Natric Agric Calcic Gypsic Salic Duripan Fragipan Placic

Sub-Horizon Designations



Horison Albik (putih) Light-colored (Value > 6 moist ) Elluvial (E master horizon*) Low in clay, Fe and Al oxides Generally sandy textured Low chemical reactivity (low CEC) Typically overlies Bh or Bt horizons

albic

*tidak semua horion E adalah horison albik


Diagnostic Subsurface Horizons Horison Argilik Akumulasi liat silikat hasil iluviasi Illuvial based on overlying horizon Jembatan liat Selimut liat Accumulation based on absolute increases compared to relevant horizon above or below. Argillic horizon. An argillic horizon is an illuvial horizon in which layer-silicate clays have accumulated to a significant extent by illuviation. They have formed below the surface of a mineral soil but may be exposed at the surface by erosion. In general, this is a B horizon which has an increase in clay content of at least 1.2 times that of the eluvial horizon above and is, in general, parallel to the surface of the polypedon. This increase of 20% in clay content occurs most in soils within a vertical distance of less than 30 cm. In case of clayey soils, this requirement would be unreasonable. If the surface horizon is greater than 40% clay, the increase of clay needed is only 8%. For sandy soils with less than 15% clay, an increase of 3% is required for meeting the criteria of an argillic horizon. In other words, if the clay content of the eluvial horizon is between 15 and 40%, an increase in clay of 20% is needed to meet the requirements for an argillic horizon. DIUNDUH DARI: soillab.ifas.ufl.edu/.../... ……. 13/2/2013


Horison Argilik

TINGGI Pasti

Horison Kandik Aktivitas liat Iluviasi Liat

RENDAH Belum tentu


Diagnostic Subsurface Horizons

Spodic Horizon 1. Akumulasi bahan organik dan aluminum (+/- besi) hasil Iluviasi 2. Berwarna gelap (value, chroma < 3) 3. Kejenuhan basa rendah (masam) 4. Terbentuk pada kondisi masam basah


Spodik

Eluviasi dan Iluviasi Eluviasi (Horison E dan Horison A)

A E

Bahan organik

Liat

A E

Bh horizon

Bt horizon Bt

Bh Spodic horizon

Argillic horizon


Diagnostic Subsurface Horizons Oxic horizon • Highly weathered (high temperatures, high rainfall)

- High in Fe, Al oxides activity - High in low-activity clays (kaolinite < smectite < vermiculite)


DESKRIPSI TANAH KARAKTERISTIK PERMUKAAN TANAH Beberapa karakteristik permukaan tanah yang penting: 1. Singkapan batuan 2. Fragmen kasar batuan 3. Erosi tanah 4. Kerak permukaan 5. Retak permukaan 6. Adanya garam 7. Pasir putih 8. Seresah tumbuhan 9. Kotoran cacing 10. Bongkahan/gumpalan 11. Pelumpuran. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Singkapan Batuan

Klasifikasi singkapan batuan

Batuan-dasar yang tersingkap di permukaan dapat mengganggu aktivitas pertanian. Singkapan batuan ini dideskripsikan dalam bentuk persentase tutupan permukaan, dan informasi lainnya seperti ukurannya, tata-letaknya, dan kekerasan batuan yang tersingkap.

Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH

Fragmen kasar di permukaan

Klasifikasi fragmen kasar di permukaan

Fragmen kasar ini termasuk fragmen yang tersingkap sebagian, dideskripsikan dalam bentuk persentase tutupan permukaan, dan ukuran fragmen. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH

Erosi Tanah Deskripsi erosi tanah harus difokuskan pada erosi tanah akibat aktivitas manusia. Biasanya sulit membedakan antara erosi alamiah dan erosi yang dipercepat akibat manusia. Erosi yang dipercepat merupakan akibat dari pengelolaan tanah yang “tidak tepat” , seperti budidaya pertanian yang tidak tepat, overgrazing dan panen vegetasi alamiah yang berlebihan.


DESKRIPSI TANAH Kategori Erosi

Klasifikasi Kategori Erosi

Erosi dapat dikelompokkan menjadi erosi oleh air dan erosi oleh angin, dan mencakup efek eksternal (off-site) seperti sedimentasi atau deposisi; kategori lainnya adalah gerakan massa tanah (longsor dan fenomena yang terkait). Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Luas area yang terpengaruh erosi

Klasifikasi luas area yang ada erosinya

Total aera yang terpengaruh oleh erosi dan sedimentasi/deposisi diestimasi dengan kelaskelas yang didefinisikan oleh SOTER (FAO, 1995)


DESKRIPSI TANAH Derajat Erosi

Klasifikasi derajat erosi

It is difficult to define classes of the degree of erosion that would be equally appropriate for all soils and environments and that would also fit the various types of water and wind erosion. Ada empat kelas derajat erosi yang direkomendasikan, dan ini harus dideskripsikan lebih lanjut, yaitu S (ringan), M (moderat), V (parah), E (sangat parah). For example, in the case of gully and rill erosion, the depth and spacing may need to be recorded; for sheet erosion, the loss of topsoil; for dunes, the height; and for deposition, the thickness of the layer . Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Klasifikasi aktivitas erosi

Aktivitas erosi Periode aktivitas erosi dan deposisi yang dipercepat dideskripsikan menurut klasifikasi berikut:


DESKRIPSI TANAH Kerak permukaan = Surface sealing Kerak permukaan digunakan untuk mendeskripsikan adanya kerak yang berkembang di permukaan ntanah setelah topsoil mengering. Kerak-kerak permukaan ini dapat menghambat perkecambahan benih , menghambat infiltrasi air, dan meningkatkan runoff. Atribut kerak permukaan adalah konsistensi (kering), dan tebalnya kerak.

Kerak permukaan yang tuidak menggulung seluruhnya pada saat mengering → Horison takyric. Kerak permukaan → Hyperochric qualifier. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Klasifikasi atribut kerak-permukaan


DESKRIPSI TANAH RETAKAN DI PERMUKAAN Retak-permukaan (Surface crack) berkembang pada tanah-tanah yang kaya tipe liat mengembang-kerut setelah mengering. Lebarnya retakan ( lebar rata-rata atau rata-rata lebar dan lebar maksimum) di permukaan diukur dengan satuan sentimeter. Rata-rata jarak di antara retakan juga diukur dengan satuan sentimeter. 1. Retakan yang membuka dan menutup secara periodik → Vertisols. 2. Retakan yang membuka dan menutup periodik , lebarnya ≥ 1 cm → Ciri vertik. 3. Retakan poligon yang dalamnya ≥ 2 cm kalau tanah mengering → Horison takyric.


DESKRIPSI TANAH Klasifikasi retakan permukaan


DESKRIPSI TANAH Garam - Salt The occurrence of salt at the surface may be described in terms of cover, appearance and type of salt.

Klasifikasi Garam di permukaan

Klasifikasi berdasarkan persentase tutupan permukaan dan ketebalan.

Catatan untuk klasifikasi tanah: Kerak terdorong oleh kristal garam → Puffic qualifier. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Pasir = Bleached sand

Klasifikasi karakteristik Pasir

The presence of bleached, loose sand grains on the surface is typical for certain soils and influences the reflection characteristics of the area and, hence, the image obtained through remote sensing. Klasifikasi berdasarkan pada persentase tutupan permukaan.


Batas-batas horison - HORIZON BOUNDARY Batas-batas horison memberikan informasi tentang proses apa ayang dominan dalam genesis tanah. Dalam kasus-kasus tertentu, dampak antropogenik masa lalu terhadap bentang-lahan. Batas-batas horison dideskripsikan dnegan indikator “kedalaman”, “kejelasan” dan “topografi”.

Kedalaman

Most soil boundaries are zones of transition rather than sharp lines of division. The depth of the upper and lower boundaries of each horizon is given in centimetres, measured from the surface (including organic and mineral covers) of the soil downwards. Precise notations in centimetres are used where boundaries are abrupt or clear. Rounded-off figures (to the nearest 5 cm) are entered where the boundaries are gradual or diffuse, avoiding the suggestion of spurious levels of accuracy. However, if boundary depths are near diagnostic limits, roundedoff figures should not be used. In this case, the depth is indicated as a medium value for the transitional zone (if it starts at 16 cm and terminates at 23 cm, the depth should be 19.5 cm). Most horizons do not have a constant depth. The variation or irregularity of the surface of the boundary is described by the topography in terms of smooth, wavy, irregular and broken. If required, ranges in depth should be given in addition to the average depth, for example 28 (25–31) cm to 45 (39–51) cm.

Catatan untuk klasifikasi tanah:

Banyak horison penciri dan sifat-penciri ditemukan pada kedalaman tertentu. Batas kedalaman yang penting adalah 10, 20, 25, 40, 50, 100 dan 120 cm. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Kejelasan dan Topografi

Kejelasan batas-horison menyatakan ketebalan zone dimana batas horison belokasi tanpa menjadi bagian dari salah satu horison terdekat. Topografi batas-horison menyatakan “smoothness” variasi kedalaman dari batas-horison.

1. 2.

3. 4.

Klasifikasi batas horison, menurut kejelasan dan topografinya

Catatan untuk klasifikasi tanah Cryoturbation → cryic horizon, Cryosols and Turbic qualifier. Tonguing of a mollic or umbric horizon into an underlying layer → Glossic qualifier. Tonguing of an eluvial albic horizon into an argic horizon → albeluvic tonguing and Glossalbic qualifier. Diffuse horizon boundaries → Nitisols.


DESKRIPSI TEKSTUR TANAH Tekstur tanah menyatakan proporsi berbagai kelas ukuran partikel primer (atau separat tanah, atau fraksi tanah) dalam suatu volume tanah dan dideskripsikan sebagai Kelas Tekstur Tanah. The names for the particle-size classes correspond closely with commonly used standard terminology, including that of the system used by the United States Department of Agriculture (USDA). However, many national systems describing particle-size and textural classes use more or less the same names but different grain fractions of sand, silt and clay, and textural classes.

KELAS TEKSTUR TANAH Nama kelas tekstur (yang mendeskripsikan kombinasi kelas ukuran partikel primer) dari suatu tanah dinyatakan dnegan kode-kode. In addition to the textural class, a field estimate of the percentage of clay is given. This estimate is useful for indicating increases or decreases in clay content within textural classes, and for comparing field estimates with analytical results. The relationship between the basic textural classes and the percentages of clay, silt and sand is indicated in a triangular form.


DESKRIPSI TANAH Pembagian Fraksi Pasir Sands, loamy sands and sandy loams are subdivided according to the proportions of very coarse to coarse, medium, fine and very fine sands in the sand fraction. The proportions are calculated from the particle-size distribution, taking the total of the sand fraction as being 100 percent. Estimasi Kelas Tekstur Tanah di Lapangan The textural class can be estimated in the field by simple field tests and feeling the constituents of the soil. For this, the soil sample must be in a moist to weak wet state. Gravel and other constituents > 2 mm must be removed. Komponen yang mempunyai “rasa” berikut: 1. Clay: “soils finger”, kohesif (melekat), dapat dibentuk, plastisitas tinggi dan mempunyai permukaan mengkilap setelah diremas (dipirit-pirit) di antara jarijari tangan. 2. Silt: “soils finger”, tidak melekat, agak sulit dibentuk, mempunyai permukaan kasar setelah diremas di antara jari-jari tangan dan rasanya sangat bertepung (seperti bedak). 3. Sand: tidak dapat dibentuk, bukan “soil finger” dan rasanya sangat berbutir grainy. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

TEKSTUR TANAH Catatan untuk klasifikais tanah : Karakteristik diagnostik penting yang berasal dari kelas tekstur: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.

Tekstur pasir berlempung atau lebih kasar hingga kedalaman ≥ 100 cm → Arenosol. Tekstur pasir halus berlempung atau lebih kasar dalam lapisan yg tebalnya ≥ 30 cm di dalam 100 cm permukaan tanah → Arenic qualifier. Tekstur debu, lempung debu, lempung liat berdebu atau liat berdebu dalam lapisan yang tebalnya ≥ 30 cm, di dalam 100 cm tanah permukaan → Siltic qualifier. A texture of clay in a layer ≥ 30 cm thick within 100 cm of the soil surface → Clayic qualifier. ≥ 30 percent clay throughout a thickness of 25 cm → vertic horizon. ≥ 30 percent clay throughout a thickness of 15 cm → vertic properties. ≥ 30 percent clay between the soil surface and a vertic horizon → Vertisol. ≥ 30 percent clay, < 20 percent change (relative) in clay content over 12 cm to layers immediately above and below, a silt/clay ratio of < 0.4 → nitic horizon. Sandy loam or finer particle size → ferralic horizon. A texture in the fine earth fraction of very fine sand, loamy very fine sand, or finer → cambic horizon. A texture in the fine earth fraction coarser than very fine sand or loamy very fine sand → Brunic qualifier. A texture of loamy sand or finer and ≥ 8 percent clay → argic and natric horizons. A texture of sand, loamy sand, sandy loam or silt loam or a combination of them → plaggic horizon. A higher clay content than the underlying soil and relative differences among medium, fine and very fine sand and clay < 20 percent → irragric horizon. A texture of sandy clay loam, clay loam, silty clay loam or finer → takyric horizon. ≥ 8 percent clay in the underlying layer and within 7.5 cm either doubling of the clay content if the overlying layer has less then 20 percent or 20 percent (absolute) more clay → abrupt textural change.


TEKSTUR TANAH Catatan untuk klasifikais tanah : Karakteristik diagnostik penting yang berasal dari kelas tekstur:

1. An abrupt change in particle-size distribution that is not solely associated with a change in clay content resulting from pedogenesis or a relative change of ≥ 20 percent in the ratios between coarse sand, medium sand, and fine sand → lithological discontinuity. 2. The required amount of organic carbon depends on the clay content, if the layer is saturated with water for ≥ 30 consecutive days in most years → organic and mineral materials. 3. The required amount of organic carbon depends on the texture → aridic properties. 4. The depth where an argic horizon starts depends on the texture → Alisols, Acrisols, Luvisols and Lixisols, and Alic, Acric, Luvic and Lixic qualifiers. 5. An argic horizon in which the clay content does not decrease by 20 percent of more (relative) from its maximum within 150 cm → Profondic qualifier. 6. Peningkatan absolut liat ≥ 3 % → Hypoluvic qualifier. 7. Rasio Debu/Liat < 0.6 → Hyperalic qualifier.



Kunci Kelas Tekrtur Tanah 1. Tidak mungkin membuat gulungan (seperti kawat) diameter 7 mm (sekitar diameter pensil) 1.1. not dirty, not floury, no fine material in the finger rills: • if grain sizes are mixed: unsorted sand US < 5 • if most grains are very coarse (> 0.6 mm): • if most grains are of medium size (0.2–0.6 mm): • if most grains are of fine size (< 0.2 mm) but still grainy: • if most grains are of very fine size (< 0.12 mm), tending to be floury:

% liat

Sand Very coarse & coarse sand Medium sand Fine sand

S CS MS FS

<5 <5 <5 <5

Very fine sand

VFS

<5

1.2. not floury, grainy, scarcely fine material in Loamy sand the finger rills, weakly shapeable, adheres slightly to the fingers:

LS

<12

1.3. similar to 1.2 but moderately floury:

SL (claypoor)

<10

sandy loam


Kunci Kelas Tekrtur Tanah 2. Possible to roll a wire of about 3–7 mm in diameter (about half the diameter of a pencil) but breaks when trying to form the wire to a ring of about 2–3 cm in diameter, moderately cohesive, adheres to the fingers 2.1 very floury and not cohesive • some grains to feel: • no grains to feel:

Silt loam Silt

SiL Si

<10 <12

2.2 moderately cohesive, adheres to the fingers, has a rough and ripped surface after squeezing between fingers and • very grainy and not sticky: • moderate sand grains: • not grainy but distinctly floury and somewhat sticky:

Sandy loam Loam Silt loam

SL L SiL

10-25 8-27 10-27

Sandy clay loam

SCL

20-35

2.3 rough and moderate shiny surface after squeezing between fingers and is sticky and grainy to very grainy:


Kunci Kelas Tekrtur Tanah 3. Possible to roll a wire of about 3 mm in diameter (less than half the diameter of a pencil) and to form the wire to a ring of about 2–3 cm in diameter, cohesive, sticky, gnashes between teeth, has a moderately shiny to shiny surface after squeezing between fingers 3.1. very grainy: 3.2. some grains to see and to feel, gnashes between teeth • moderate plasticity, moderately shiny surfaces: • high plasticity, shiny surfaces:

Sandy clay (Liat berpasir)

SC

35-55

Clay loam (Lempung liat) Clay (Liat)

CL C

25-40 40-60

SiCL SiC HC

25-40 40-60 >60

3.3. no grains to see and to feel, does not gnash between teeth • low plasticity: Silty clay loam • high plasticity, moderately shiny surfaces: Silty clay (Liat berdebu) • high plasticity, shiny surfaces: Heavy clay Iliat berat)


Kunci Kelas Tekrtur Tanah Catatan: Penentuan tekstur tanah di lapangan tergfantung pada komposisi mineralogis liat. Kunci-kunci yang disajikan di atas, terutama untuk tanah-tanah yang mengandung illite, chlorite dan / atau vermiculite. Liat Smectite lebih plastis, dan liat kaolinitik lebih lengket. Sehingga adanya liat Smektit dapat mengakibatkan overestimasi, dan adanya liat kaolinitik dapat mengakibatkan under-estimasi. Source: Adapted from Schlichting, Blume and Stahr, 1995.


DESKRIPSI TANAH Fragmen Batuan dan Artefacts Keberadaan fragmen batuan dapat mempengaruhi status ketersediaan hara, pergerakan air, penggunaan dan pengelolaan tanah. Hal ini juga mencerminkan asal-usul dan tingkat perkembangan tanah. Artefacts (sections on artefacts and description of artefacts [below]) are useful for identifying colluviation, human occupation, and industrial processes. Large rock and mineral fragments (> 2 mm) and artefacts are described according to abundance, size, shape, state of weathering, and nature of the fragments. The abundance class limits correspond with the ones for surface coarse fragments and mineral nodules, and the 40 percent boundary coincides with the requirement for the skeletic phase. Kalau fragmen batuan tidak terdistribusi secara teratur di dalam suatu horison, tetapi membentuk semacam “stone line”, maka harus dinyatakan dnegan jelas.


DESKRIPSI TANAH Kelimpahan (volume) fragmen batuan dan artefacts


DESKRIPSI TANAH Ukuran fragmen batuan dan artefacts Klasifikasinya disjaikan dalam tabel berikut.

Catatan untuk klasifikais tanah: Karakteristik penciri penting yang berasal dari jumlah fragmen batuan: 1. < 20 percent (by volume) fine earth averaged over a depth of 75 cm or to continuous rock → Leptosols and Hyperskeletic qualifier. 2. ≥ 40 percent (by volume) gravel or other coarse fragments averaged over: • a depth of 100 cm or to continuous rock → Skeletic qualifier; • a depth of 50–100 cm → Endoskeletic qualifier; • a depth of 20– 50 cm → Episkeletic qualifier. 3. ≥ 20 (volume) artefact dalam lapisan atas upper 100 cm → Technosols. 4. < 40 persen volume berupa kerikil atau fragmen kasar lain dalam semua lapisan hingga 100 cm atau horison petroplinthic, plinthic atau salic → Arenosols. 5. Material Fragmental, rongga-rongga di antara fragmen diisi oleh bahan organik → Histosols. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Klasifikasi fragmen batuan dan artefact


DESKRIPSI TANAH Bentuk fragmen Batuan

Klasifikasi bentuk fragmen batuan

Bentuk umum atau kebulatan fragmen batuan dapat dideskripsikan sebagai: Pipih, Bersudut, Membulat, Bulat (Rounded) Catatan unt klasifikasi: Layers with rock fragments of angular shape overlying or underlying layers with rock fragments of rounded shape or marked differences in size and shape of resistant minerals between superimposed layers → Diskontinyuitas litologis Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Kondisi pelapukan fragmen batuan dan artefact

Klasifikasi kondisi pelapukan fragmen kasar

Kondisi pelapukan fragmen kasar dideskripsikan sebagai F (Lapuk ringan), W (lapuk) dan S (lapuk lanjut).

Catatan untuk klasifikasi tanah A layer with rock fragments without weathering rinds overlying a layer with rock fragments with weathering rinds → lithological discontinuity. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Sifat fragmen batuan

Sifat fragmen batuan dideskripsikan dengan menggunakan terminologi yang sama dnegan deskripsi tipe-batuan. Untuk fragmen mineral primer, dapat dipakai kode-kode lainnya. Fragments of individual weatherable minerals (e.g. feldspars and micas) may be smaller than 2 mm in diameter. Nevertheless, where present in appreciable quantities, such fragments should be mentioned separately in the description. For artefacts, see section on artefacts.

Catatan untuk klasifikasi tanah: Fragmen batuan yang tidak mempunyai sifat litologis sama dnegan batuan dibawahnya → lithological discontinuity.


DESKRIPSI TANAH Derajat dekomposisi dan humifikasi gambut – peat In most organic layers, the determination of the texture class is not possible. More valuable is an estimate of the degree of decomposition and humification of the organic material. Warna dan persentase jaringan tumbuhan aslinya pada bahan organik kering atau basah, dapat digunakan untuk estimasi derajat dekomposisinya. Catatan unbtuk klasifikasi tanah: 1. Histosol mempunyai lebih dari dua-pertiga (volume) jaringan tumbuhan yang masih dapat dikenali → Fibric qualifier. 2. Histosols have between two-thirds and one-sixth (by volume) recognizable plant tissues → Hemic qualifier. 3. Histosol mempunyai kurang dari seper-enam (1/6) (volume) ) jaringan tumbuhan yang masih dapat dikenali → Sapric qualifier.


DESKRIPSI TANAH Estimasi lapang dan kode derajat dekomposisi dan humifikasi gambut - peat


DESKRIPSI TANAH WARNA TANAH (MATRIX) Warna tanah mencerminkan komposisi dan kondisi oksidasi-reduksi saat ini dan masa lalu yang dialami oleh tanah. Warna biasanya ditentukan oleh penyelimutan partikel sangat halus bahan organik humik (warna gelap), oksida besi (kuning, coklat, orange dan merah), Oksida manganese (hitam) dan lainnya; atau ditentukan oleh warna bahan induk tanah. The colour of the soil matrix l of each horizon should be recorded in the moist condition (or both dry and moist conditions where possible) using the notations for hue, value and chroma as given in the Munsell Soil Color Charts (Munsell, 1975). Hue is the dominant spectral colour (red, yellow, green, blue or violet), value is the lightness or darkness of colour ranging from 1 (dark) to 8 (light), and chroma is the purity or strength of colour ranging from 1 (pale) to 8 (bright). Where there is no dominant soil matrix colour, the horizon is described as mottled and two or more colours are given. Selain notasi warna, nama-nama warna baku Munsell juga harus diberikan.


DESKRIPSI TANAH WARNA TANAH For routine descriptions, soil colours should be determined out of direct sunlight and by matching a broken ped with the colour chip of the Munsell Soil Color Charts. For special purposes, such as for soil classification, additional colours from crushed or rubbed material may be required. The occurrence of contrasting colours related to the structural organization of the soil, such as ped surfaces, may be noted. Where possible, soil colour should be determined under uniform conditions. Early morning and late evening readings are not accurate. Moreover, the determination of colour by the same or different individuals has often proved to be inconsistent. Because soil colour is significant with respect to various soil properties, including organic matter contents, coatings and state of oxidation or reduction, and for soil classification, cross-checks are recommended and should be established on a routine basis.


DESKRIPSI WARNA TANAH Catatan untuk kalsifikasi tanah: Intermediate colours should be recorded where desirable for the distinction between two soil horizons and for purposes of classification and interpretation of the soil profile. Intermediate hues (important for qualifiers, such as Chromic or Rhodic, and for diagnostic horizons, such as cambic) that may be used are: 3.5, 4, 6, 6.5, 8.5 and 9 YR. Misalnya: 3.5 YR, berarti bahwa nilai intermediate-hue lebih dekat dengan nilai 2.5 YR daripada 5 YR; 4 YR berarti lebih dekat ke 5 YR, dst. Kalau “value” dan “chroma” mendekati batas-batas diagnostik, tidak boleh dilakukan pembulatan nilai, tetapi pencatatan akurat harus dilakukan dnegan menggunakan nilai-nilai intermediate, atau dnegan jalan menambah tanda + atau tanda - .


Pentingnya diagnostik hue, value dan chroma: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25.

Abrupt changes in colour not resulting from pedogenesis → lithological discontinuity. Redder hue, higher value or higher chroma than the underlying or an overlying layer → cambic horizon. Hue redder than 10 YR or chroma ≥ 5 (moist) → ferralic properties, Hypoferralic and Rubic qualifier. Hue 7.5 YR or yellower and value ≥ 4 (moist) and chroma ≥ 5 (moist) → Xanthic qualifier. Hue redder than 7.5 YR or both hue 7.5 YR and chroma > 4 (moist) → Chromic qualifier. Hue redder than 5 YR, value < 3.5 (moist) → Rhodic qualifier. Hue 5 YR or redder, or hue 7.5 YR and value ≤ 5 and chroma ≤ 5, or hue 7.5 YR and value ≤ 5 and chroma 5 or 6, or hue 10 YR or neutral and value and chroma ≤ 2, or 10 YR 3/1 (all moist) → spodic horizon. Hue 7.5 YR or yellower or GY, B or BG; value ≤ 4 (moist); chroma ≤ 2 (moist) → puddled layer (anthraquic ). Hue N1 to N8 or 2.5 Y, 5 Y, 5 G or 5 B → reductimorphic colours of the gleyic colour pattern. Hue 5 Y, GY or G → gyttja (limnic material). Chroma < 2.0 (moist) and value < 2.0 (moist) and < 3.0 (dry) → voronic horizon. Chroma ≤ 2 (moist) → Chernozem. Chroma ≤3 (moist) and value ≤ 3 (moist) and ≤ 5 (dry) → mollic and umbric horizon. Value and chroma ≤ 3 (moist) → hortic horizon. Value ≤ 4 (moist) and ≤ 5 (dry) and chroma ≤ 2 (moist) → plaggic horizon. Value > 2 (moist) or chroma > 2 (moist) → fulvic horizon. Value ≤ 2 (moist) and chroma ≤ 2 (moist) → melanic horizon. Values 4 to 8 and chroma 4 or less (moist) and values 5–8 and chromas 2–3 (dry) → albic horizon. Lower value or chroma than the overlying horizon → sombric horizon. Value ≥ 3 (moist) and ≥ 4.5 (dry) and chroma ≥ 2 (moist) → aridic properties. Value ≤ 4 (moist) → coprogenous earth or sedimentary peat (limnic material). Value 3, 4 or 5 (moist) → diatomaceous earth (limnic material). Value ≥ 5 (moist) → marl (limnic material). Value ≤ 3.5 (moist) dan chroma ≤ 1.5 (moist) → Pellic qualifier. Value ≥ 5.5 (dry) → Hyperochric qualifier.


DESKRIPSI TANAH MOTTLING : BECAK-BECAK Mottles are spots or blotches of different colours or shades of colour interspersed with the dominant colour of the soil. They indicate that the soil has been subject to alternate wetting (reducing) and dry (oxidizing) conditions. Becak dideskripsikan dengan indikator “kelimpahan”, ukuran, kontras, batas, dan warna. Selain itu, “bentuk”, posisi, dan ciri-ciri lainnya juga dapat dicatat. Catatan untuk klasifikais tanah:

1. Mottles of oxides in the form of coatings or in platy, polygonal or reticulate patterns are diagnostic for the anthraquic (plough pan), hydragric, ferric, plinthic and petroplinthic horizons and for the gleyic colour pattern. 2. Mottles of oxides in the form of concretions or nodules are diagnostic for the hydragric, ferric, plinthic, petroplinthic and, pisoplinthic horizons and for the stagnic colour pattern. 3. Redox depleted zones in macropores with a value ≥ 4 and a chroma ≤ 2 are diagnostic for the hydragric horizon. 4. Becak atau selimut yang berupa jarosite atau schwertmannite merupakan penciri untuk horison thionic dan Aceric qualifier. 5. Becak-becak berbentuk konsnetrasi kuning merupakan diagnostik (penciri) horison thionik.


DESKRIPSI TANAH Warna Becak Biasanya warna becak dideskripsikan secara umum sesuai dengan Munsell Soil Color Charts.

Klasifikasi kelimpahan becak-becak

Kelimpahan Becak Kelimpahan becak dideskripsikan dalam “Kelas-kelas” yang menyatakan persentase permukaan yang ditempati becak. Batas-batas kelas sesuai dnegan nodul mineral. When the abundance of mottles does not allow the distinction of a single predominant matrix or groundmass colour, the predominant colours should be determined and entered as soil matrix colours.


DESKRIPSI TANAH Ukuran Bercak

Klasifikasi ukuran becak

Kelas-kelas yang digunakan untuk menyatakan diameter individual bercak. Kelas-kelas ini sesuai dengan kelas-kelas ukuran nodul mineral.


DESKRIPSI TANAH Kontras Becak

Klasifikasi ke-Kontras-an becak

Kontras warna antara becak dan matriks tanah dapat dideskripsikan sebagai Haint, Distinch, dan Prominent.

Batas Becak

Klasifikasi batas antara becak dan matriks

Batas antara becak dan matriks dideskripsikan sebagai “tebal” zone transisi warna.


DESKRIPSI TANAH SOIL REDOX POTENTIAL AND REDUCING CONDITIONS Determination of redox potential by field method Soil redox potential is an important physico-chemical parameter used to characterize soil aeration status and availability of some nutrients. The redox potential is also used in the WRB classification to classify redoximorphic soils. To measure redox potential (DIN/ISO Draft, DVWK, 1995), drive a hole into the soil using a rigid rod (stainless steel, 20–100 cm long, with a diameter that is 2 mm greater than the redox electrodes) to a depth about 1–2 cm less than the desired depth to be measured. Immediately clean the platinum surface of the redox electrode with sandpaper and insert the electrode about 1 cm deeper than the prepared hole. At least two electrodes should be installed for each depth being measured. After at least 30 minutes, measure the redox potential with a millivoltmeter against a reference electrode (e.g. Ag/AgCl in KCl of the glass electrode of pH measurements, installed in a small hole on the topsoil that has been filled with 1-M KCl solution). For dry topsoil, a salt bridge (plastic tube 2 cm in diameter and with open ends, filled with 0.5 percent (M/M) agar in KCl solution) should be installed in a hole beside and at the depth of the platinum electrodes. In this tube, the reference electrode should be installed.

The measured voltage (Em) is related to the voltage of the standard hydrogen electrode by adding the potential of the reference electrode (e.g. +244 millivolt at 10 °C of Ag/AgCl in 1 M KCl, +287 of

Calomel electrode).

For interpretation, the results should be transformed to rH values using the formula: rH = 2pH + 2Eh/59 (Eh in mV at 25 °C).


DESKRIPSI TANAH Karakteristik Redoximorphic tanah dan hubungannya dnegan nilai rH dan prosesproses tanah


DESKRIPSI TANAH Kondisi Reduksi Reductimorphic properties of the soil matrix reflect permanently wet or at least reduced conditions. They are expressed by neutral (white to black: Munsell N1 to N) or bluish to greenish colours (Munsell 2.5 Y, 5 Y, 5 G, 5 B). The colour pattern will often change by aeration in minutes to days owing to oxidation processes. The presence of FeII ions can be tested by spraying the freshly exposed soil surface with a 0.2-percent (M/V) α,α dipyridyl solution in 10-percent (V/V) acetic acid solution. The test yields a striking reddish-orange colour in the presence of Fe2+ ions but may not give the strong red colour in soil materials with a neutral or alkaline soil reaction. Care is necessary as the chemical is slightly toxic.

Catatan untuk klasifikasi tanah: An rH value of < 20 is diagnostic for reducing conditions in Gleysols, Planosols and Stagnosols, and stagnic and gleyic lower level units of other RSGs. Gaseous emissions (methane, carbon dioxide, etc.) are diagnostic for the Reductic qualifier.


DESKRIPSI TANAH Pola warna Reductimorphic dan keberadaan senyawa Fe


DESKRIPSI TANAH CARBONATES : Kandungan Karbonat dalam tanah dapat berupa residu bahan induk atau hasil bentukan baru (carbonate sekunder). Karbonat sekunde rterutama berbentu bubuk halus kapur, selimut pada agregat, konkresi, kerak permukaan atau bawah permukaan, atau “hard banks”. The presence of calcium carbonate (CaCO3) is established by adding some drops of 10-percent HCl to the soil. The degree of effervescence of carbon dioxide gas is indicative for the amount of calcium carbonate present. In many soils, it is difficult to distinguish in the field between primary and secondary carbonates. Classes for the reaction of carbonates in the soil matrix are defined as per Table xx. The reaction to acid depends upon soil texture and is usually more vigorous in sandy material than in finetextured material with the same carbonate content. Other materials, such as roots, may also give an audible reaction. Dolomite biasanya bereaksi lebih lambat dan kurang kuat dibanding kalsit. Karbonat sekunder harus diuji secara terpisah; biasanya mereka ini bereaksi lebih intensif dengan HCl.

Classification of carbonate reaction in the soil matrix


DESKRIPSI TANAH Bentuk Karbonat

The forms of secondary carbonates in soils are diverse and are considered to be informative for diagnostics of soil genesis. Soft carbonate concentrations are considered to be illuvial, and hard concretions are generally believed to be of hydrogenic nature.

Untuk Klasifikasi tanah:

Klasifikasi bentuk karbonat sekunder

Pentingnya kandungan karbonat: 1. ≥ 2 percent calcium carbonate equivalent → calcaric material. 2. ≥ 15 percent calcium carbonate equivalent in the fine earth, at least partly secondary → calcic horizon. 3. Indurated layer with calcium carbonate, at least partly secondary → petrocalcic horizon. 4. 15–25 percent calcium carbonate equivalent in the fine earth, at least partly secondary → Hypocalcic qualifier. 5. ≥ 50 percent calcium carbonate equivalent in the fine earth, at least partly secondary → Hypercalcic qualifier. 6. Where a soil has a calcic horizon starting 50–10 cm from the soil surface, it is only a Calcisol if the soil matrix between 50 cm from the soil surface and the calcic horizon is calcareous throughout. 7. Calcisols and Gypsisols can only have an argic horizon where the argic horizon is permeated with calcium carbonate (Calcisols) or calcium carbonate or gypsum (Gypsisols). Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH pH tanah di lapang

Soil pH expresses the activity of the hydrogen ions in the soil solution. It affects the availability of mineral nutrients to plants as well as many soil processes. When the pH is measured in the field, the method used should be indicated on the field data sheet. The field soil pH should not be a substitute for a laboratory determination. Field soil pH measurements should be correlated with laboratory determinations where possible. In the field, pH is either estimated using indicator papers, indicator liquids (e.g. Hellige), or measured with a portable pH meter in a soil suspension (1 part soil and 2.5 parts 1 M KCl or 0.1 M CaCl2 solution). After shaking the solution and waiting for 15 minutes, the pH value can be read. For the measurement, use a transparent 50-ml plastic cup with marks for 8 cm3 soil (~ 10 g) and 25 ml solution.

Klasifikasi nilai pH

Catatan untuk Klasifikasi Tanah Pada kebanyakan tganah, nilai pH berkorelasi dnegan kejenuhan basa, hal ini penting dalam klasifikasi tanah di lapangan. Akan tetapi hal ini memerlukan pembuktian di laboratorium.


DESKRIPSI TANAH Kandungan Bahan organik tanah “Bahan organik” refers to all decomposed, partly decomposed and undecomposed organic materials of plant and animal origin. It is generally synonymous with humus although the latter is more commonly used when referring to the well decomposed organic matter called “substansi humik”. The content of organic matter of mineral horizons can be estimated from the Munsell colour of a dry and/or moist soil, taking the textural class into account. This estimation is based on the assumption that the soil colour (value) is due to a mixture of dark coloured organic substances and light coloured minerals. This estimate does not work very well in strongly coloured subsoils. It tends to overestimate organic matter content in soils of dry regions, and to underestimate the organic matter content in some tropical soils. Therefore, the organic matter values should always be locally checked as they only provide a rough estimate.


DESKRIPSI TANAH Estimasi kandungan BOT berdasarkan Munsell soil colour


DESKRIPSI TANAH Kandungan BOT untuk klasifikasi tanah 1. If saturated with water for ≥ 30 consecutive days in most years (unless drained): • ≥ [12 + (clay percentage of the mineral fraction × 0.1)]% organic carbon or • ≥ 18 percent organic carbon, else ≥ 20 percent organic carbon → organic material. 2. Organic material saturated with water for ≥ 30 consecutive days in most years (unless drained) → histic horizon. 3. Organic material saturated with water for < 30 consecutive days in most years → folic horizon. 4. Weighted average of ≥ 6 percent organic carbon, and ≥ 4 percent organic carbon in all parts → fulvic and melanic horizon. 5. Organic carbon content of ≥ 0.6 percent → mollic and umbric horizon. 6. Organic carbon content of ≥ 1.5 percent → voronic horizon. (Note: the ratio of organic carbon to organic matter is about 1:1.7–2.) Write the range or average value in the description sheet. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH STRUKTUR TANAH Soil structure refers to the natural organization of soil particles into discrete soil units (aggregates or peds) that result from pedogenic processes. The aggregates are separated from each other by pores or voids. It is preferred to describe the structure when the soil is dry or slightly moist. In moist or wet conditions, it is advisable to leave the description of structure to a later time when the soil has dried out. For the description of soil structure, a large lump of the soil should be taken from the profile, from various parts of the horizon if necessary, rather than observing the soil structure in situ. Sruktur tanah dideskripsikan dengan indikator “grade”, “ukuran” dan “tipe” agregat. Kalau suatu horison tanah mengandung agregat dnegan bermacam “grade”, ukuran atau tipe, semuanya harus dideskripsikan dan hubungan satu sama lain harus dijelaskan.


DESKRIPSI TANAH


DESKRIPSI TANAH Grade Struktur

In describing the grade or development of the structure, the first division is into apedal soils (lacking soil structure) and pedal soils (showing soil structure).

Klasifikasi struktur

In apedal or structureless soil, no aggregates are observable in place and there is no definite arrangement of natural surfaces of weakness. Structureless soils are subdivided into single grain and massive. Single-grain soil material has a loose, soft or very friable consistence and consists on rupture of more than 50 percent discrete mineral particles. Massive soil material normally has a stronger consistence and is more coherent on rupture. Massive soil material may be further defined by consistence (below) and porosity (below). Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Klasifikasi Tipe Struktur


DESKRIPSI TANAH Tipe Struktur

Kode tipe-struktur tanah

Tipe-tipe alamiah dari struktur tanah adalah gumpal, pipih, granuler, dan lainnya. Where required, special cases or combinations of structures may be distinguished, which are subdivisions of the basic structures. Kode-kode yang direkomendaiskan adalah seperti pada tabek berikut. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

DESKRIPSI TANAH Ukuran Struktur

Kelas ukuran kombinasi

Size classes vary with the structure type. For prismatic, columnar and platy structures, the size classes refer to the measurements of the smallest dimension of the aggregate. Combined classes may be Constructed. Where a second structure is present, its relation to the first structure is described. The first and second structures may both be present (e.g. columnar and prismatic structures). The primary structure may break down into a secondary structure (e.g. prismatic breaking into angular blocky). The first structure may merge into the second structure (e.g. platy merging into prismatic).

Kombinasi struktur tanah


DESKRIPSI TANAH Kelas-kelas ukuran untuk Tipe-tipe struktur tanah


DESKRIPSI STRUKTUR TANAH Catatan untuk klasifikasi tanah: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.

Soil structure, or absence of rock structure (the term “rock structure” also applies to unconsolidated sediments in which stratification is still visible) in half of the volume or more of the fine earth → cambic horizon. Soil structure sufficiently strong that the horizon is not both massive and hard or very hard when dry (prisms larger than 30 cm in diameter are included in the meaning of massive if there is no secondary structure within the prisms) → mollic, umbric and anthric horizons. Granular or fine subangular blocky soil structure (and worm casts) → voronic horizon. Columnar or prismatic structure in some part of the horizon or a blocky structure with tongues of an eluvial horizon → natric horizon. Moderate to strong, angular blocky structure breaking to flat-edged or nutshaped elements with shiny ped faces → nitic horizon. Wedge-shaped structural aggregates with a longitudinal axis tilted 10–60 ° from the horizontal → vertic horizon. Wedge-shaped aggregates → vertic properties. Platy structure → puddled layer (anthraquic horizon). Uniformly structured → irragric horizon. Separations between structural soil units that allow roots to enter have an average horizontal spacing of ≥ 10 cm → fragic horizon. Platy or massive structure → takyric horizon. Platy layer → yermic horizon. Strong structure finer than very coarse granular → Grumic qualifier. Massive and hard to very hard in the upper 20 cm of the soil → Mazic qualifier. A platy structure and a surface crust → Hyperochric qualifier. Stratification in ≥ 25 percent of the soil volume → fluvic material.


DESKRIPSI TANAH

Konsistensi Konsistensi mencerminkan derajat kohesi atau adhesi dari massa tanah. Konsistensi mencakup ciri-ciri tanah seperti friability, plasticity, stickiness dan resistensi terhadap kompresi. Sifat ini sangat tergantung pada jumlah dan tipe liat, bahan organik dan kandungan lengas tanah. For reference descriptions, a recording of consistence is required for the dry, moist and wet (stickiness and plasticity) states. Where applicable, the smeariness (thixotropy) and fluidity may also be recorded. For routine descriptions, the soil consistence in the natural moisture condition of the profile may be described. Konsistensi basah selalu dapat dideskripsikan, dan kondisi lembab kalau tanahnya kering, dengan jalan menambahkan air ke sampel tanah.


DESKRIPSI TANAH Konsistensi pada kondisi kering

Konsistensi massa tanah pada kondisi kering

Konsistensi kering ditentukan dengan jalan “memecah” atau “meremas” massa tanah kering udara di antara jari tangan “thumb and forefinger”.


DESKRIPSI TANAH Konsistensi pada kondisi LEMBAB Consistence when moist is determined by attempting to crush a mass of moist or slightly moist soil material. Konsistensi massa tanah pada kondisi lembab


DESKRIPSI TANAH Konsistensi pada kondisi basah: Kelekatan maksimum dan plastisitas maksimum Soil stickiness depends on the extent to which soil structure is destroyed and on the amount of water present. The determination of stickiness should be performed under standard conditions on a soil sample in which structure is completely destroyed and which contains enough water to express its maximum stickiness. In this way, the maximum stickiness will be determined and comparison between degrees of stickiness of various soils will be feasible. The same principle applies to soil plasticity.


DESKRIPSI TANAH Kelekatan

Stickiness is the quality of adhesion of the soil material to other objects determined by noting the adherence of soil material when it is pressed between thumb and Finger. Klasifikasi kelekatan tanah


DESKRIPSI TANAH Plastisitas tanah

Plasticity is the ability of soil material to change shape continuously under the influence of an applied stress and to retain the compressed shape on removal of stress. Determined by rolling the soil in the hands until a wire about 3 mm in diameter has been formed Klasifikasi plastisitas tanah


Deskripsi Konsistensi Tanah Catatan untuk klasifikasi tanah 1. Extremely hard consistence when dry → petrocalcic horizon. 2. Surface crust with very hard consistence when dry, and very plastic and sticky consistence when wet → takyric horizon. 3. Air-dry clods, 5–10 cm in diameter, slake or fracture in water within 10 minutes → fragic horizon.

http://saret.ifas.ufl.edu/publications/bsbc/chap6.htm Soil consistency states for a sand and a clay soil (friable soil is best for tillage).

4. Penetration resistance at field capacity of ≥ 50 kN m-1 → fragic horizon. 5. Penetration resistance of ≥ 450 N cm-2 → petroplinthic horizon. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

Deskripsi Tanah Status lengas tanah Soil-water status is the term used for the moisture condition of a horizon at the time the profile is described. The moisture status can be estimated in the field. Catatan untuk klasifikasi tanah: 1. The definitions of mineral and organic materials and of the histic, folic and cryic horizons depend on the soil-water status. 2. Temporarily water-saturated → Gelistagnic, Oxyaquic and Reductaquic qualifiers. 3. Organic material floating on water → Floatic qualifier. 4. Permanently submerged under water < 2 m → Subaquatic qualifier. 5. Flooded by tidewater, but not covered at mean low tide → Tidalic qualifier. 6. Artificially drained histic horizon → Drainic qualifier.


Deskripsi Lengas Tanah Klasifikasi status lengas-tanah


Klasifikasi soil moisture regimes Aquic Udic Ustic Xeric Aridic

: wet, anaerobic, mottled : adequate water throughout year : Water may be deficient, but usually available during growing season : Most moisture during the noncropping time, dry Mediterranean : Long dry periods

Sumber: http://staff.aub.edu.lb/~webeco/SIM215soiltaxonomy.htm ....... 16/2/2013

Deskripsi Bobot Isi (BI) Tanah BOBOT ISI Bulk density is defined as the mass of a unit volume of dry soil (105 °C). This volume includes both solids and pores and, thus, bulk density reflects the total soil porosity. Low bulk density values (generally below 1.3 kg dm-3) generally indicate a porous soil condition. Bulk density is an important parameter for the description of soil quality and ecosystem function. High bulk density values indicate a poorer environment for root growth, reduced aeration, and undesirable changes in hydrologic function, such as reduced water infiltration.

There are several methods of determining soil bulk density. One method is to obtain a known volume of soil, dry it to remove the water, and weigh the dry mass. Another uses a special coring instrument (cylindrical metal device) to obtain a sample of known volume without disturbing the natural soil structure, and then to determine the dry mass. For surface horizons, a simple method is to dig a small hole and fill it completely with a measured volume of sand. Field determinations of bulk density may be obtained by estimating the force required to push a knife into a soil horizon exposed at a field moist pit wall.


Deskripsi BOBOT ISI Tanah Estimasi Bobot Isi Tanah di Lapangan (Untuk tanah-tanah mineral) Observasi

Bentuk agregat tanah

Bobot isi Kg/dm-3 Kode

Tanah-tanah berpasir, berdebu dan berlempung dnegan kandungan liat rendah Many pores, moist materials drop easily out of the auger; materials with vesicular pores, mineral soils with andic properties.

Granular

< 0.9 BD1

Sample disintegrates at the instant of sampling, many pores visible on the pit wall.

single grain, granular

0.9–1.2 BD1

Sample disintegrates into numerous fragments after application of weak pressure.

single grain, subangular, angular blocky

1.2–1.4 BD2

Knife can be pushed into the moist soil with weak pressure, sample disintegrates into few fragments, which may be further divided.

subangular and angular blocky, prismatic, platy

1.4–1.6 BD3

Knife penetrates only 1–2 cm into the moist soil, some effort required, sample disintegrates into few fragments, which cannot be subdivided further.

prismatic, platy, (angular blocky)

1.6–1.8 BD4

Very large pressure necessary to force knife into the soil, no furtherdisintegration of sample.

Prismatic

> 1.8 BD5


Deskripsi BOBOT ISI Tanah Estimasi Bobot Isi Tanah di Lapangan (Untuk tanah-tanah mineral) Observasi

Bentuk agregat tanah

Bobot isi Kg/dm-3 Kode

Tanah-tanah berlempung dengan kandungan liat tinggi, Tanah berliat When dropped, sample disintegrates into numerous fragments, further disintegration of subfragments after application of weak pressure.

Angular blocky

1.0-1.2 BD1

When dropped, sample disintegrates into few fragments, further disintegration of subfragments after application of mild pressure.

Angular blocky, Prismatic, Platy, Columnar

1.2 -1.4 BD2

Sample remains mostly intact when dropped, further disintegration possible after application of large pressure.

coherent, prismatic, platy, (columnar, angular blocky, platy, wedge– shaped)

1.4 -1.6 BD3

Sample remains intact when dropped, no further disintegration after application of very large pressure.

coherent (prismatic, columnar, wedge– shaped)

> 1.6 BD 4, 5

Note: If organic matter content is > 2%, bulk density has to be reduced by 0.03 kg dm-3 for each 1% increment in organic matter content. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

Deskripsi Bobot Isi Tanah Catatan untuk klasifikasi tanah: 1. 2.

Source: according to Ad-hoc-AG-Boden, 2005.

Bobot Isi 0.90 kg dm-3 atau kurang → Ciri Andik. Dalam tapak-bajak, bobot isi ≥ 20 percent (relative) lebih tinggi dari lapisan lumpur → Horison anthraquic.

Root penetration is not only limited by bulk density, but also by texture. Finetextured soils contain fewer pores in size and abundance than needed for unrestricted root growth. Therefore, the evaluation of bulk density has to take soil texture into account. Untuk keperluan evaluasi, juga dapat digunakan “packing density” (PD = BD + 0.009 ・% clay).


Deskripsi Porositas Tanah POROSITAS Voids include all empty spaces in the soil. They are related to the arrangement of the primary soil constituents, rooting patterns, burrowing of animals or any other soil-forming processes, such as cracking, translocation and leaching. The term void is almost equivalent to the term pore, but the latter is often used in a more restrictive way and does not, for example, include fissures or planes. Voids are described in terms of type, size and abundance. In addition, continuity, orientation or any other feature may also be recorded.

Klassifikasi Porositas 1 2 3 4 5

Very low Low Medium High Very high

<2 % 2–5 % 5–15 % 15–40 % > 40 %

Porositas merupakan indikasi total volume rongga yg dapat dikenali dnegan lensa pembesaran 10x, diukur dengan areanya, dan dicatat sebagai persentase permukaan yang dihuni oleh pori. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE

Deskripsi Porositas Tanah Type

There is a large variety in the shape and origin of voids. It is impractical and usually not necessary to describe all different kinds of voids comprehensively. Emphasis should be given to estimating the continuous and elongated voids.

The major types of voids may be classified in a simplified way. In most cases, it is recommended that only the size and abundance of the channels, which are mostly continuous tubular pores, be described (Figure xx). For the other types of voids, the following size and abundance classes should serve as a guide for the construction of suitable classes for each category .

Klasifikasi Pori I

Interstitial

Controlled by the fabric, or arrangement, of the soil particles, also known as textural voids. Subdivision possible into simple packing voids, which relate to the packing of sand particles, and compound packing voids, which result from the packing of non-accommodating peds. Predominantly irregular in shape and interconnected, and hard to quantify in the field.

B

Vesicular

Discontinuous spherical or elliptical voids (chambers) of sedimentary origin or formed by compressed air, e.g. gas bubbles in slaking crusts after heavy rainfall. Relatively unimportant in connection with plant growth.

V

Vughs

Mostly irregular, equidimensional voids of faunal origin or resulting from tillage or disturbance of other voids. Discontinuous or interconnected. May be quantified in specific cases.

C

Channel

Elongated voids of faunal or floral origin, mostly tubular in shape and continuous, varying strongly in diameter. When wider than a few centimetres (burrow holes), they are more adequately described under biological activity.

P

Plane

Most planes are extra-pedal voids, related to accommodating ped surfaces or cracking patterns. They are often not persistent and vary in size, shape and quantity depending on the moisture condition of the soil. Planar voids may be recorded, describing width and frequency.

Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Rome, 2006

Charts for estimating size and abundance of pores


Deskripsi Pori Tanah UKURAN PORI Diameter rongga-rongga yang memanjang atau tubular dideskripsikan sebagai “sangat halus” hingga “sangat kasar”. KELIMPAHAN PORI The abundance of very fine and fine elongated pores as one group, and of medium and coarse pores as another group is recorded as the number per unit area in a square Decimetre.

Klassifikasi diameter pori

FM = fine and medium; FF = fine and very fine; MC = medium and coarse.

Klassifikasi Kelimpahan pori

Catatan nuntuk Klasifikasi Tanah

1. Vesicular layer below a platy layer or pavement with a vesicular layer → yermic horizon. 2. Sorted soil aggregates and vesicular pores → anthraquic horizon. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Rome, 2006

Deskripsi Tanah Klasifikasi kelimpahan selimut

KONSENTRASI MATERIAL TANAH Pengkayaan sekunder, sementasi dan re-orientasi. SELIMUT = SELAPUT = Coatings

This section describes clay or mixed-clay illuviation features, coatings of other composition (such as calcium carbonate, manganese, organic or silt), reorientations (such as slickensides and pressure faces), and concentrations associated with surfaces but occurring as stains in the matrix (“hypodermic coatings”). All these features are described according to their abundance, contrast, nature, form and location. Kelimpahan Selaput For coatings, an estimate is made of how much of the ped or aggregate faces is covered. Corresponding criteria should be applied when the cutanic feature is related to other surfaces (voids, and coarse fragments) or occurs as lamellae.

Klasifikasi ke-kontras-an selimut

F

Faint

Surface of coating shows only little contrast in colour, smoothness or any other property to the adjacent surface. Fine sand grains are readily apparent in the cutan. Lamellae are less than 2 mm thick.

D

Distinct

Surface of coating is distinctly smoother or different in colour from the adjacent surface. Fine sand grains are enveloped in the coating but their outlines are still visible. Lamellae are 2–5 mm thick.

P

Prominent

Surface of coatings contrasts strongly in smoothness or colour with the adjacent surfaces. Outlines of fine sand grains are not visible. Lamellae are more than 5 mm thick.

Kontras Selaput Klasifikasi konstras selimut seperti berikut ini. Sumber: Guidelines for soil description. Fourth edition. FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS. Rome, 2006

Deskripsi “Coating“ Tanah Sifat

Sifat selimut dapat dideskripsikan seperti pada tabel berikut. Bentuk Selimut For some coatings, the form may be informative for their Genesis. For example, manganese and iron– manganese coatings of dendroidal form indicate their formation owing to poor infiltration and periodically reductive conditions because of percolating water. Lokasi Selimut Lokasi selimut atau akumulasi liat dijelaskan. For pressure faces and slickensides, no location is given because they are by definition located on pedfaces.

Klasifikasi Sifat Selimut C : Clay - Liat S : Sesquioxides H ; Humus CS : Clay and sesquioxides CH : Clay and humus (organic matter) CC : Calcium carbonate GB : Gibbsite HC : Hypodermic coatings (Hypodermic coatings, as used here, are field-scale features, commonly only expressed as hydromorphic features. Micromorphological hypodermic coatings include non-redox features [Bullock et al., 1985].) JA : Jarosite MN: Manganese SL : Silica (opal) SA : Sand coatings ST : Silt coatings SF : Shiny faces (as in nitic horizon) PF : Pressure faces SI : Slickensides, predominantly intersecting (Slickensides are polished and grooved ped surfaces that are produced by aggregates sliding one past another.) SP : Slickensides, partly intersecting SN : Slickensides, non intersecting Source: Adapted from Schoeneberger et al, 2002.


Deskripsi Tanah Catatan untuk klasifikasi tanah: 1. Evidence of silica accumulation, e.g. as coatings → petroduric horizon. 2. Slickensides → vertic horizon and vertic properties. 3. Evidence of clay illuviation → argic and natric horizons. 4. Cracked coatings on sand grains → spodic horizon. 5. Uncoated sand and silt grains → Greyic qualifier. 6. Clay coatings in the argic horizon → Cutanic qualifier. 7. Illuviation in the form of lamellae in the argic, natric and spodic horizon → Lamellic qualifier. 8. Coatings that have a different colour from the matrix.

Klasifikasi Bentuk Selimut C CI

DI DE DC O

Continuous Continuous irregular (non-uniform, heterogeneous) Discontinuous irregular Dendroidal Discontinuous circular Other

Klasifikasi lokasi selimut dan akumulasi liat P PV PH CF LA VO BR NS

Pedfaces Vertical pedfaces Horizontal pedfaces Coarse fragments Lamellae (clay bands) Voids Bridges between sand grains No specific location


Deskripsi Tanah Cementation dan Compaction Keberadaan kompaksi atau sementasi dideskripsikan dnegan indikator “sifat”, “kontinyuitas”, “struktur”, “agent dan Derajat”. Compacted material has a firm or stronger consistence when moist and a close packing of particles. Cemented material does not slake after 1 hour of immersion in water.

KONTINYUITAS

Klasifikasi kontinyuitas sementasi/ Kompaksi B

Broken

The layer is less than 50 percent cemented or compacted, and shows a rather irregular appearance.

D

Discontinues

The layer is 50–90 percent cemented or compacted, and in general shows a regular appearance.

C

Continues

The layer is more than 90 percent cemented or compacted, and is only interrupted in places by cracks or fissures .

Klasifikasi fabrik lapisan semen/kompak

Klasifikasi kontinyuitas sementasi / kompaksi.

STRUKTUR

Fabrik atau struktur lapisan sementasi atau kompaksi.


Deskripsi Tanah Sementasi dan Kompaksi Nature The nature of cementation or compaction is described according to the cementing agent or compacting activity. Degree Klasifikasi derajat sementasi / kompaksi.

Klasifikasi sifat sementasi / kompaksi K Q KQ F FM FO I GY C CS M P NK

Carbonates Silica Carbonates–silica Iron Iron–manganese (sesquioxides) Iron–organic matter Ice Gypsum Clay Clay–sesquioxides Mechanical Ploughing Not known

Klasifikasi derajat sementasi / kompaksi. N : Non-cemented and non-compacted : Neither cementation nor compaction observed (slakes in water). Y : Compacted but non-cemented Compacted mass is appreciably harder or more brittle than other comparable soil mass (slakes in water). W : Weakly cemented : Cemented mass is brittle and hard, but can be broken in the hands. M : Moderately cemented : Cemented mass cannot be broken in the hands but is discontinuous (less than 90 percent of soil mass). C : Cemented : Cemented mass cannot be broken in the hands and is continuous (more than 90 percent of soil mass). I : Indurated : Cemented mass cannot be broken by body weight (75-kg standard soil scientist) (more than 90 percent of soil mass).


Deskripsi Sementasi / Kompaksi Tanah Catatan untuk klasifikais Tanah: 1. 2. 3. 4. 5. 6.

Es ditutup oleh bahan organik → Histosols. Sementasi oleh es atau kristal es mudah dilihat → cryic horizon. ≥ 75 % es (volume) → Glacic qualifier. Sementasi oleh bahan organik dan aluminium → spodic horizon. Horison spodik sementasi → Ortsteinic qualifier. Iron pan that is 1–25 mm thick and is continuously cemented by a combination of organic matter, iron and/or aluminium → Placic qualifier. 7. Strongly cemented or indurated → petrocalcic, duric, gypsic and plinthic horizons, Petric, Petrogleyic and Petrosalic qualifiers. 8. Cementation on repeated wetting and drying → plinthic horizon. 9. Roots cannot penetrate except along vertical fractures that have an average horizontal spacing of ≥ 10 cm and occupy < 20 percent (by volume) of the layer → petrocalcic, petroduric and petrogypsic horizons. 10. Horison sementasi atu indurasi kuat yang terdiri atas bongkahan-bongkahan yang panjang horisontalnya < 10 cm → Fractipetric dan Fractiplinthic qualifiers. 11. Kompaksi alamiah atau artifisial → Densic qualifier.


Deskripsi Tanah Konsentrasi Mineral Konsnetrasi-mineral mencakup berbagai macam konsentrasi kristalin sekunder, microcrystalline dan amorphous substansi non-organik sebagai pengisinya, Konkresi lunak, konsentrasi yang bentuknya tidak teratur (becak-becak), nodul-nodul material yang terbentuk secara pedogenesis. Gradual transitions exist with mottles (above), some of which may be considered as weak expressions of nodules. The mineral concentrations are described according to their abundance, kind, size, shape, hardness, nature and colour.


Deskripsi Tanah Abundance (by volume) Kelimpahan konsnetrasi mineral dapat diklasifikasikan seperti pada tabel.

Macam - Jenis Macam-mavcam konsentrasi mineral dapat diklasifikasikan seperti pada tabel. T C SC S N IP IC R O

Klasifikasi kelimpahan konsnetrasi mineral (volume) N V F C M A D

None Very few 0–2 Few Common 2–15 Many Abundant Dominant

0%

2–5 15–40 40–80 > 80

Crystal Concretion A discrete body with a concentric internal structure, generally cemented. Soft concretion Soft segregation (or soft accumulation) Differs from the surrounding soil mass in colour and composition but is not easily separated as a discrete body. Nodule Discrete body without an internal organization. Pore infillings Including pseudomycelium of carbonates or opal. Crack infillings Residual rock fragment Discrete impregnated body still showing rock structure. Other


Deskripsi Tanah Size and shape Ukuran dan bentuk konsentrasi mineral.

Klasifikasi ukuran dan bentuk

Hardness Kekerasan konsentrasi mineral. Nature Konsnetrasi Mineral dideskripsikan sesuai dengan komposisi dan substansi yang terkandung di dalamnya. Colour The general colour names are usually sufficient to describe the colour of the nodules (similar to mottles) or of artefacts.


Deskripsi Tanah Warna konsentrasi mineral WH RE RS YR BR BS RB YB YE RY GE GR GS BU BB BL MC

Sifat konsentrasi mineral

White - Putih Red - Merah Reddish - Kemerahan Yellowish red Brown - Coklat Brownish - Kecoklatan Reddish brown Yellowish brown Yellow - Kuning Reddish yellow Greenish - Kehijauan Grey - Kelabu Greyish Blue - Biru Bluish-black - Hitam kebiruan Black - Hitam Multicoloured


Deskripsi “Konsentrasi Mineral” Catatan untuk klasifikasi tanah 1. ≥ 10 percent (by volume) of weakly cemented to indurated, 2. silica-enriched nodules (durinodes) → duric horizon. 3. Reddish to blackish nodules of which at least the exteriors are at least weakly cemented or indurated → ferric horizon. 4. Firm to weakly cemented nodules or mottles with a stronger chroma or redder hue than the surrounding material → plinthic horizon. 5. Strongly cemented or indurated reddish to blackish nodules → pisoplinthic horizon.


Deskripsi Tanah: Aktivitas Biologis AKAR - Roots The recording of both the size and the abundance of the roots is in general sufficient to characterize the distribution of roots in the profile. In specific cases, additional information can be noted, such as a sudden change in root orientation. The abundance of roots can only be compared within the same size class. The abundance of fine and very fine roots may be recorded similarly as for voids , expressed in the number of roots per decimetre square. Ukuran - Size (diameter) Klasifikasi ukuran akar.

Klasifikasi diameter akar VF F M C

Very fine Fine Medium Coarse

< 0.5 mm 0.5–2 2–5 >5

Note: Additional codes are: FF, very fine and fine; FM, fine and medium; and MC, medium and coarse.

Kelimpahan akar N V F C M

None Very few Few Common Many

< 2 mm 0 1–20 20–50 50–200 > 200

> 2 mm 0 1–2 2–5 5–20 > 20

Abundance Klasifikasi ekelimpahan akar.


Deskripsi Tanah Aktivitas Biologis lainnya Biological features, such as krotovinas, termite burrows, insect nests, worm casts and burrows of larger animals, are described in terms of abundance and kind. In addition, specific locations, patterns, size, composition or any other characteristic may be recorded. Kelimpahan Keliimpahan aktivitas biologis dideskripsikan secara general. Macam-Jenis-Kind Contoh-contoh aktivitas biologis.

Kelimpahan aktivitas biologis N F C M

None Few Common Many

Contoh Aktivitas Biologis A B BO BI C E P T I

Artefacts Burrows (unspecified) Open large burrows Infilled large burrows Charcoal Earthworm channels Pedotubules Termite or ant channels and nests Other insect activity.


PROFIL TANAH - HIPOTETIK Tanah adalah lapisan tipis yang menutupi permukaan bumi , kecuali permukaan air dan singkapan batuan yang terbuka. Sifat dan ciri tanah ditentukan oleh faktor lingkungannya. Lima faktor dominan dalam genesis (pembentukan) tanah: 1. Ilkim 2. Bahan induk (rocks and physical and chemical derivatives of same), 3. Relief 4. Organisms (fauna and flora), 5. Waktu.

Sumber: http://www.fao.org/Wairdocs/ILRI/x5546E/x5546e04.htm ……. DIUNDUH 16/2/2013

DESKRIPSI TANAH

………. Selanjutnya ….….

Diunduh dari: http://blog.ub.ac.id/mastertommy/files/2013/01/panduan_deskripsi.pdf …. 13/2/2013

BAHAN KAJIAN MK. DASAR ILMU TANAH. Smno.jursntnh.fpub.febr2013

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