BAHAN KAJIAN
MK. DASAR ILMU TANAH
Foto: smno.kampus.ub.janu2013
TANAH MOLLISOLS
Ordo “Mollisol” , namanya berasal dari kata Latin
“mollis”, yang berarti “lunak, soft”.
These mineral soils have developed on grasslands, a
vegetation that has extensive fibrous root systems. The
topsoil of Mollisols is characteristically dark and rich with
organic matter, giving it a lot of natural fertility.
Tanah-tanah ini jenuh dengan kation-kation basa (Ca2+,
Mg2+, Na+, dan K+) , unsur hara esensial bagi tumbuhan.
Mollisols merupakan tanah-tanah yang sangat subur.
Diunduh dari: http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1130447032&topicorder=7&maxto=16&minto=1
………….. 4/3/2013
TANAH MOLLISOLS
RINGKASAN
1. Vegetasi: Prairie, Lahan berumput
2. Iklim: variety of soil temperature regimes
(cryic to hypothermic)
3. Rezim lengas-tanah: variety of soil
moisture regimes - aquic, udic, ustic, or
xeric; rataan curah hujan tahaunan 200 800 mm
4. Ciri tanah yang utama: Kandungan BOT,
Kejenuhan Basa tinggi
5. Horison Penciri: argilik, Kambik (Natrik,
Kalsik, Petrokalsik, gypsik, albik, duripan)
6. Epipedon: Molik
7. Major processes: melanization,
decomposition, humification,
pedoturbation
8. Ciri khas: Tanah-tanah snagat subur
MOLLISOLS:
1. Grassland soils of steppes and prairies
(base rich soils)
2. Deposits and landscapes with a wide
range of ages
3. Many Mollisols are formed on deposits
associated with glaciation
(unconsolidated quaternary materials) calcareous rich aolian deposits
supported the formation of Mollisols
4. In other areas they develop in residuum
weathered from sedimentary rocks
TANAH MOLLISOLS
KONDISI LINGKUNGAN MOLLISOLS
IKLIM
Mollisols terdapat pada beragam zone iklim, berkisar dari rezim suhu cryik (mis.
Mongolia, North Dakota), frigid (mis. Iowa), mesik (mis. Di Pakistan), atau
thermik (mis. Di Oklahoma bagian tengah).
Rata-rata curah hujan tahunan berkisar dari 200 mm dg vegetasi speta rumputpendek hingga 800 mm dengan vegetasi rumput-tinggi.
For example, climate in the Great Plains favor the development of
Mollisols: severe, dry winters with much wind and relatively slight
accumulation of snow; relatively moist springs and droughty
summers with some thunderstorms and/or tornadoes (e.g. typical
climate of the Great Plains).
Mollisols terdapat pada kondisi rezim lengas-tanah: udik, ustik, xerik, dan aquik.
TANAH MOLLISOLS
KONDISI LINGKUNGAN MOLLISOLS
VEGETASI
Kebanyakan Mollisols telah terbentuk pada kondisi vegetasi prairie atau padang-rumput. Ada
berbagai tipe : Dalam prairie rumput-tinggi, tingginya rumput dewasa 1 - 3-m; sedangkan
dalam prairie rumput-pendek, tingginya rumput hanya 13 – 30 cm.
The prairie or grassland vegetation add plentiful raw organic matter to the soil, mostly by in
situ root death. Legumes in the prairie or grassland community contribute considerable
nitrogen to the soil.
Prairies develop under relatively moist condistions, whereas grass steppe develop under
drier climate. Prairie extension was largest approximately 5000 to 2000 B.P. Common species
of prairie vegetation are bluestem (Andropogon gerardi), buffalo grass (Buchloe dactyloides),
or western wheat grass (Agropyron smithii).
Mollisols ADALAH TANAH-TANAH SUBUR , menempati sekitar 25% lahan pertanian di USA
dna menghasilkan gandum, kedelai, dan alfalfa.
Beberapa tanah Mollisols berkembang pada kondisi vegetasi hutan, drainage jelek dan/atau
bahan induk berkapur atau bahan yang kaya basa-basa.
TANAH MOLLISOLS
KONDISI LINGKUNGAN MOLLISOLS
Relief - Topografi:
Mollisols cover a wide range of land forms (e.g. flat or gently rolling plains, undulating
plains, mountain areas). Extensions of prairies by fire have formed preferentially on
topography over which fire moves easily (e.g. ridgetops, windward slopes).
Bahan Induk Tanah:
Mollisols ditemukan pada deposits dan lanskap yang umurnya sangat beragam.
Banyak Mollisols terbentuk pada deposits yg berhubungan dnegan proses glasiasi
(material tidak-padu dari zaman Quaternary), dimana deposit aeolian yg kaya kapur
mendukung pembentukan Mollisols. Akan tetapi, pada beberapa kasus lainnya
mollisols berkemnag pada bahan induk residuum hasil pelapukan batuan sedimen.
Time:
The age for development of Mollisols is indifferent and closely associates to the other
environmental factors.
TANAH MOLLISOLS
PROSES PEMBENTUKAN MOLLISOLS
Melanisasi didefinisikan sebagai proses terjadinya “warna gelap” tanah karena
penambahan bahan organik dan ini merupakan proses dominan pada Mollisols.
Melanisasi yg terjadi pada Mollisols didukung oleh masuknya bahan organik
langsung ke tganah mineral.
Vegetasi prairie dan padang-rumput mengakumulasi sejumlah besar bahan
organik.
Microbial decomposition of organic materials in the soil produces relatively
stable, dark compounds (humification). Residue from plants partially
decomposes on the soil surface and enriches the upper part of the A horizon
through incorporation by soil fauna. Earthworms, ants, cicada nymphs, and
rodents (e.g. gophers) are considered to be important agents in promoting the
incorporation and breakdown of litter into the soil.
Aktivitas biologis pada Mollisols lebih besar dibandingkan dnegan tanah-tanah
hutan, terutama aktivitas cacing tanah sangat banyak pada Mollisols.
TANAH MOLLISOLS
PROSES PEMBENTUKAN MOLLISOLS
Pedoturbasi yg intensif dapat menghasilkan diferensiasi horison.
Pada Mollisols ada beberapa macam pedoturbation :
1. Faunal pedoturbation: Pencampuran material tanah oleh
binatang, seperti rayap, cacing-tanah, moluska, dan rodent,
2. Human pedoturbation: Pengolahan tanah,
3. Congelli pedoturbation (cryoturbation): pencampuran material
tanah oleh siklus beku-cair seperti dilanskap tundra dan alpine
4. Argilli pedoturbation: mixing of materials in the solum by
shrink and swell movements of expansible clays as they wet
and dry in the water cycles within the soil.
TANAH MOLLISOLS
PROSES PEMBENTUKAN MOLLISOLS
Dalam beberapa Mollisols ada bukti-bukti proses eluviasi dan iluviasi koloid organik dan
koloid mineral (liat, oksida besi dan mangan) di sepanjang rongga di antara agregat , dan
permukaan agregat menjadi terselimuti oleh kutan yg berwarna gelap (organo-argillans).
For example, an eluviated horizon is present in the Albolls and an argillic horizon is found
in Argiudolls. Percolation of water is influenced by systems of cracks, krotovinas, and
macropores made by roots and soil fauna.
Pada Mollisols yang teksturnya medium dan drainagenya bagus, adanya horison A dan B
yg kandungan liatnya hampir sama dapat dijelaskan oleh proses-proses berikut:
1. Di daerah iklim dimana evapotranspirasi melebihi presipitasi (curah hujan) mineral liat
dapat ditranslokasikan ke arah atas dari horison B ke horison A ,
2. Pembentukan liat yg cepat di horison A pada kondisi lengas tanah yg drainagenya
bagus dan vegetasi padang-rumput,
3. Eluviasi sangat lambat dalam tanah-tanah padang rumput, karena terjadinya
pembentukan kompleks mineral dan koloid organik , dan penyerapan yg cepat air
oleh akar tumbuhan,
4. pedoturbation by prairie ants (Formica cinerea), which builds mounds where clay,
organic material, phosphorus, and potassium is accumulated.
TANAH MOLLISOLS
PROSES PEMBENTUKAN MOLLISOLS
Deposition of loess material (dust) and blown out dry organic matter support the
development of Mollisols (wind erosion). The deposited material is rich in
calcium and other nutrients, which supports microbial activity.
In many Mollisols the calcareous loess was leached of carbonates and varying
degrees of acidity have developed. After leaching of carbonates, clay formation
reaches its maximum and clay movement might occur when precipitation
exceeds evapotransiration.
Erosi oleh air dapat menyebabkan kumulasi dan penebalan epipedon MOLIK. Tanahtanah ini biasanya berada di lereng-bawah atau dataran-banjir. Biasanya mereka ini
disebut dengan istilah “cumulic”.
Di daerah yang digarap secara intensif, banyak tanah telah kehilangan material tanah
lapisan atas (permukaan) karena erosi.
TANAH MOLLISOLS
SIFAT DAN CIRI MOLLISOLS
A major characteristic of Mollisols is the high accumulation and decomposition of soil
organic matter (SOM). SOM includes a variety of materials ranging form newly added
material to the thoroughly decomposed and polymerized residual matter (humus).
The grassland or prairie vegetation produce high amount of SOM, where as much as 80 %
of the total biomass is in the roots. For example, the above-ground production of tallgrass prairie ranges from 1700 to 3500 kg/ha, whereas the dry weight of roots is about 3
times higher.
Under prairie vegetation more than 50 % of the biomass is added to the soil annually,
almost all the above ground parts and at least 30 % of the underground parts. As a result,
most of the OM is deposited within the profile itself, the highest amount within the mollic
epipedon.
Due to decomposition and humification stable humus is formed, which is composed of
complex organic compounds synthesized by the soil organisms and resistant polymers of
phenolic and aromatic functional groups. The average C:N ratio for grassland soils is
nearly constant, ranging from 10:12.
TANAH MOLLISOLS
SIFAT DAN CIRI MOLLISOLS
Mollisols exhibit a mollic epipedon, which is dark in color, humus-rich, relatively fertile,
and show a thickness of about 40 to 75 cm. If earthworm activity is high wormholes or
macropores are formed which are pathways for preferential flow.
Additional factors that are associated with the accumulation of organic matter in Mollisols
are a high base saturation (> 50 %), high cation exchange capacity, and a high water
holding capacity.
Generally, the A horizon shows a granular structure, whereas the B horizon exhibits
blocky and prismatic soil structure. Many clay minerals have been formed from
pedogenesis. Inherited micas have been depleted of potassium and valence charges of
the layers have been lowered by weathering producing a wide array of clay minerals in
Mollisols. Coatings are found on ped surfaces, which are called organo-argillans
composed of mineral and organic components.
The eluviation and illuviation of clay might form an argillic or a cambic diagnostic horizon.
Because the formation of the argillic horizon is relatively slow, its presence in Mollisols
indicates soils formed on older, more stable geographic surfaces.
TANAH MOLLISOLS
KLASIFIKASI MOLLISOLS
While it is true that all Mollisols have mollic epipedons, the presence of a mollic epipedon
does not automatically qualify a soil as a Mollisol. Epipedons that are made to meet the
mollic criteria by the common practice of agricultural liming are excluded from criteria when
placing a soil in the Mollisol order.
Kriteria untuk memenuhi kualifikasi Mollisol :
1. Epipedon Molik
2. Kejenuhan basa 50 % atau lebih dalam semua horison hingga kedalaman 180 cm; atau
hingga kontak litik atau paralitik kalau ada.
Ada tujuh subordo dalam Mollisols:
Albolls:
Albolls are Mollisols with an albic horizon, aquic conditions for some time in most years, and
redox concentrations within 100 cm of the mineral soil surface. Below the albic horizon there
is an argillic or natric horizon. Processes which develop Albolls are eluviation/illuviation and
reduction of iron and manganese oxides due to wet soil moisture conditions. They occur on
nearly level interfluve ridgetops or closed depressions.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
KLASIFIKAIS MOLLISOLS
Aquolls:
They develop under aquic conditions thus they show soil properties associated
with wetness: (i) redoximorphic features, (ii) accumulation of organic matter, (iii)
a histic epipedon overlying the mollic epipedon, (iv) accumulation of calcium
carbonate or exchangeable sodium near the soil surface.
Rendolls:
They are formed in humid regions under forest, formed from calcareous parent materials
(e.g. limestone, calcareous glacial till, chalk, shell deposits). The mollic epipedon must be
less than 50-cm thick and may be rather weakly expressed due to the dilution effect of
the light-colored, calcium-rich material from which it has formed. Rendolls do not have
argillic or calcic horizons.
This suborder is not subdivided into great groups, but a number of subgroups are
identified on the basis of a shallow lithic contact, cryic soil temperature regime, vertic
character, and presence or absence of a cambic horizon.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Albolls
Albolls are the Mollisols that have both an albic horizon and fluctuating ground water.
Most supported grass or grass and shrub vegetation. In early stages of development,
some are thought to have supported forest vegetation that was later succeeded by
grass. Most of the soils have gentle slopes and are used as cropland.
Aquolls
Aquolls adalah Mollisols yang basah. Most have supported vegetation of grasses,
sedges, and forbs, but some supported forest vegetation. Most have been artificially
drained, and are used as cropland.
Cryolls
Cryolls are the cool or cold, more or less freely drained Mollisols. They support forest,
grass, or grass and shrub vegetation. Cryolls banyak digunakan sebagai padang
gembalaan ternak. Sebagian tanah-tanah ini dikelola sebagai hutan dan pasture.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Rendolls
Rendolls are the Mollisols that are of humid regions and formed in highly
calcareous parent materials, such as limestone, chalk, and drift composed
mainly of limestone, or on shell bars.
They formed mostly under forest vegetation or under grass and shrubs. Most are
used as cropland or pasture, but some are used as rangeland or forest.
Udolls
Udolls adalah mollisols yang drainagenya bagus dan berkembang di daerah iklim
humid.
Vegetasi selama proses pembentukkannya didominasi oleh rumput prairie yang
tinggi. Lereng tidak terlalu curam, hampir semua atanah-tanah ini dikelola
sebagai lahan pertanian, sebagian dikelola sebagai padang rumput gembalaan.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
KLASIFIKASI MOLLISOLS
Xerolls:
Xerolls are Mollisols that have a xeric soil moisture regime. They
ordinarily have a thick mollic epipedon, or cambic or argillic horizon
and an accumulation of carbonates in the lower solum.
Cryolls:
This is the most extensive Mollisol suborder worldwide. Borolls
form under a frigid and cryic soil temperature regime.
They occur in Eastern Europe and Asia (the northern Russian
steppes), and the northern Great Plains and in mountainous areas
of the western United States.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Ustolls
Ustolls are the more or less freely drained Mollisols of subhumid to semiarid
climates. They are mostly on the western Great Plains. They also are common
throughout the Rocky Mountain States.
Most of the Ustolls on the Great Plains supported grass vegetation when the
country was settled. Some Ustolls, mostly those in the mountains of the Western
States, supported forest vegetation.
Rainfall comes mainly during a growing season, often in heavy showers, but is
erratic. Drought is frequent and may be severe. Without irrigation, the low
supply of moisture usually limits crop yields. During a drought, soil blowing can
be a problem.
Kebanyakan tanah-tanah ini dikelola sebagai lahan pertanian tanaman pangan
yang produktif.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
KLASIFIKASI MOLLISOLS
Ustolls:
That are the freely drained Mollisols of semiarid to subhumid climates with ustic
soil moisture regime. Erratic rainfall occurs mostly during the growing season,
and summer drought is a frequent, but erratic occurence. Most Ustolls show an
accumulation of calcium carbonate in the soil profile (calcic horizon).
Udolls:
Udolls berkembang pada kondisi rezim lengas-tanah UDIK dalam iklim
kontinental di daerah temperate dan tropika. Tanah-tanah ini terbentuk pada
deposit glasial akhir-Pleistocene atau Holocene atau deposit lainnya, di bawah
vegetasi prairie rumput-tinggi. Epipedon molik berkembang dnegan baik.
Biasanya di bawahnya ada horison Argillik atau Kambik.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Xerolls
Xerolls adalam mollisols yang drainagenya bagus, berkembang di daerah iklim
Mediterranean.
They are in the Pacific Northwest, California, Idaho, Nevada, and western Utah.
Xerolls are dry for extended periods in summer, but moisture moves through most
of the soils in winter and is stored above the deep layers or above bedrock in
normal years.
The vegetation at the time of settlement was dominantly bunchgrass and shrubs or
trees in the areas that have a mesic or frigid temperature regime, a savanna of
perennial grasses and a savanna of annual grasses and oak species on the Xerolls in
California that have a thermic temperature regime.
Many irrigated crops are grown on the Xerolls in the United States, especially where
the temperature regime is thermic or mesic. Most of the soils that have gentle or
moderate slopes are used as cropland. The very steep soils are used mainly as
rangeland, but some are used as forest.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
KLASIFIKASI MOLLISOLS
Several soil moisture regimes are considered at subgroup level ranging from dry to wet
conditions: Xeric (e.g. Xeric Argialbolls), aridic (e.g. Aridic Calcixerolls), udic (e.g. Udic
Paleustolls), ustic (e.g. Ustic Argicryolls), and aquic (e.g. Aquic Natrustolls).
Great groups dan subgroups dibedakan oleh horison penciri bawah-permukaan: (i) argillic
- mis. Argialbolls, Argic Duraquolls, (ii) natric - mis. Natraquolls, Natric Duraquolls, (iii)
calcic - mis. Calciaquolls, Calcic Haplocryolls, (iv) petrocalcic - mis. Petrocalcic Palexerolls,
(v) gypsic - mis. Clcixerolls, (vi) albic - mis. Albic Cryoborolls,or (vii) duripan - mis.
Duricryolls, Duric Natrixerolls (viii) Kambik - mis. Eutropeptic Rendolls.
Tanah-tanah yang berkembang pada bahan induk vulkanik dengan bobot isi yang rendah
(< 1.0 g/cm3) dan fragmen kasarnya (>2 mm) lebih dari 35 % disebut 'andic', 'aquandic',
atau 'vitrandic' (mis. Andic Cryoborolls, Aquandic Argialbolls, Vitrandic Durixerolls).
Istilah 'vertic' dipakai kalau Mollisols menunjukkan karakteristik seperti retakan, agregat
berbentuk “wedge”, bidang-geser, dan kaya liat tipe mengembang (mis. Vertic Cryaquolls,
Vertic Haprendolls, Vertic Palexerolls).
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Penciri Mollisols
In Mollisols the significant characteristic is the presence of a mollic epipedon. There are
similar soils which show a dark, humus-rich surface horizon high in exchangeable calcium
and magnesium. Differences in chemical composition (e.g. phosphorus content)
differentiate Mollisols from other soils with similar morphology but different genetic
histories.
The mollic epipedon may occur in soils of other orders in addition to Mollisols.
Mollic epipedons are present in many Vertisols, in which case the plastic, shrink-swell
nature of the clay is a more significant soil property than the mollic epipedon. Also, mollic
epipedons are found in the Inceptisol order with cambic horizons that more significantly
influence the profile than does the mollic epipedon, which in some cases may have been
formed by lime applications.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Penciri Mollisols
Tanah-tanah pririe seperti Argiudolls akan berkembang menjadi
Albaquolls kalau pelapukan, produksi liat, dan diferensiasi horison
dapat berlangsung.
Failure to meet the thickness criteria for a mollic epipedon results in
potential classification of many of these soils as Mollic Hapludalfs if
they are well drained and have an argillic horizon.
Tanpa horison argilik, tetapi dnegan horison kambik, tanah-tanah
seperti ni diklasifikasikan sebagai Inceptisols.
Diunduh dari: ………….. 25/2/2013
TANAH MOLLISOLS
KLASIFIKASI MOLLISOLS
1. Mollisols dengan horison GLOSSIK, yaitu penyusupan material albik ke dalam horison
bawah-permukaan disebut 'glossic' (mis.Glossic Natriborolls, Glossic Natrustolls).
2. Some Mollisols are differentiated by soil texture. Mollisols that have a sandy or sandyskeletal particle-size class throughout a layer extending from the mineral soil surface to
the top of an argillic horizon at a depth of 50 cm to 100 cm are denoted as 'arenic' (e.g.
Arenic Argiaquolls , Arenic Argiborolls). Other Mollisols that have a mollic epipedon 50
cm or more thick with a texture finer than loamy fine sand are called 'pachic' (e.g. Pachic
Haplustolls, Pachic Argiustolls). Mollisols that have a sandy particle-size class throughout
the upper 75 cm of the argillic horizon, or throughout the entire argillic horizon if it is less
than 75 cm thick are classified as 'psammentic' (e.g. Psammentic Argiudolls ).
3. Tebalnya epipedon molik membedakan Mollisols dengan sebutan 'entik'. Misalnya,
tebalnya epipedon molik harus kurang dari 50 cm pada Entic Vermustolls dan tebalnya
kurang dari 75 cm pada Entic Vermudolls. Mollisols yang tipis/dangkal diklasifikan
menjadi 'lithic' (mis. Lithic Endoaquolls, Lithic Rendolls, Lithic Argicryolls). Epipedon molik
yang lebih tebal diklasifikasikan sebagai 'cumulic', tebalnya epipedon > 50 cm (mis.
Cumulic Cryaquolls).
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
KLASIFIKASI MOLLISOLS
1.
Mollisols yang banyak mengandung liang-liang cacing, kotoran cacing, atau
liang-liang hewan tanah , diklasifikasikan sebgaai 'vermic' (mis. Vermudolls).
2.
Mollisols dengan epipedon histik (mis. Histic Cryaquolls) dan tanah-tanah
dnegan epipedon molik , yg sebenarnya adalah histosol terkubur, yang batas
atasnya berada didalam 100 cm tanah-mineral permukaan (mis. Thapto-Histic
Cryaquolls).
3.
Kondisi lengas-tanah yg basah membentuk mollisols aquik atau oxyaquic
Mollisols, dimana sifat-sifat redoximorphic tampak jelas (mis. Aquic
Natrixerolls, Oxyaquic Argiborolls).
4.
Mollisols where the argillic horizon has its upper boundary 60 cm or more
below the mineral soil surface are classified by the term 'pale' (e.g.
Paleborolls). In those soils the argillic horizon is the result of an earlier
weathering regime no longer present.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Mollisols adalah tanah-tanah yg
mempunyai horison permukaan
berwarna gelap , relatif kaya bahan
organik.
Tanah-tanah ini kaya basa-basa,
sehingga sangat subur.
Mollisols berkembang di bawah
vegetasi rumput pada kondisi iklim yg
mempunyai defisit air musiman
tingkat moderat hingga signifikan.
Mollisols menyusun sekitar 7%
permukaan lahan dunia yang bebas es.
Diunduh dari: online.sfsu.edu/jerry/geog317/resources/Mollisols_l.pdf ………….. 25/2/2013
TANAH MOLLISOLS
Profil tanah Mollisol,
menunjukkan horison
permukaan yg warnanya gelap,
kaya humus.
(sumber: U.S. Department of
Agriculture, Natural Resources
Conservation Service, Soil Survey
Staff).
Diunduh dari: http://www.britannica.com/EBchecked/media/19537/Mollisol-soil-profile-showing-a-typically-dark-surface-
TANAH MOLLISOLS
Konsep sentral dari Mollisols adalah
bahwa tanah-tanah ini mempunyai
horison permukaan yg berwarna gelap,
dan kaya basa-basa.
Hampir semua tanah-tanah ini
mempunyai epipedon Molik.
Banyak juga tanah ini yang mempunyai
horison argilik atau natrik, atau horizon
Kalsik.
Beberapa tanah mempunyai horison
albik.
Ada juga tanah-tanah ini yang mempunyai
duripan atau horison petrokalik.
Diunduh dari: http://soils.usda.gov/technical/classification/orders/mollisols.html ………….. 2/3/2013
TANAH MOLLISOLS
Mollisol di Minnesota
Tanah ini mempunyai horison A setebal 16 inches
terletak di atas horison Bt yang tipis.
Tanda anak panah menunjukkan batas atas dan
batas bawah horison Bt (horison tempat akumulasi
liat). Horison C terletak di bawah horison Bt. Tanda
panah paling bawha menunjukkan becak karbonat.
Bahan induk tanah ini kaya kalsium karbonat.
Over time, the carbonate has been removed from
the upper part of the profile by water leaching
through the soil.
In a humid climate, where carbonate is found in the
subsoil, weathering has not progressed sufficiently
for the horizon to be called a B horizon. This is
designated the C horizon.
Diunduh dari: lawr.ucdavis.edu ………….. 2/3/2013
TANAH MOLLISOLS
Mollisols mempunyai horison permukaan
berwarna gelap (epipedon molik) yang kaya bahan
organik.
Lapisan permukaan ini terasa lunak dan “fluffy
feel”.
Tanah-tanah ini terbentuk dari bahan induk yang
kaya hara, dan biasanya di bawah vegetasi padang
rumput.
Tanah-tanah ini secara alamiah subur dan mampu
menyimpan banyak air tersedia.
Tanah-tanah ini dikelola sebagai lahan pertanian.
Penciri tanah ini adalah epipedon molik.
Urutan horison dalam profil tanah adalah:
A1, A2, AB, Bw, BC, C.
Diunduh dari: www.swac.umn.edu ………….. 2/3/2013
TANAH MOLLISOLS
Horison dalam Mollisols
The A horizon, called topsoil by most growers, is the surface mineral layer
where organic matter accumulates. Over time, this layer loses clay, iron,
and other materials to leaching. This loss is called eluviation. Materials
resistant to weathering, such as sand, tend to remain in the A horizon as
other materials leach out. The A horizon provides the best environment
for the growth of plant roots, microorganisms, and other life.
The B horizon, or subsoil, is often called the zone of accumulation where
chemicals leached out of the A and E horizon accumulate. The word for
this accumulation is illuviation. The B horizon has a lower organic matter
content than than the topsoil and often has more clay. The A, E, and B
horizons together are known as the solum. This part of the profile is
where most plant roots grow.
The C horizon lacks the properties of the A and B horizons. It is the soil
layer less touched by soil-forming processes and is usually the parent
material of the soil.
Development of color or structure. The symbol indicates that a horizon
has developed enough to show some color or structure but not enough to
show illuvial accumulation of material.
Diunduh dari: http://www2.vcdh.virginia.edu/madison/webship/rotorua/order7.html ………….. 2/3/2013
TANAH MOLLISOLS
Bahan induk tanah kasa basa-basa dan kalkareus,
termasuk limestone, loess, atau pasir yg
diendapkan angin.
The main processes that lead to the formation of
grassland Mollisols are melanisation,
decomposition, humification and pedoturbation.
Mollisols have deep, high organic matter, nutrientenriched surface soil (A horizon), typically between
60–80 cm in depth. This fertile surface horizon,
known as a mollic epipedon, is the defining
diagnostic feature of Mollisols.
Epipedom Molik terbentuk dari proses jangka
panjang poenambahan bahan organik yg berasal
dari akar-akar tumbuhan, dan mempunyai
struktur-tanah granuler yang lunak.
Diunduh dari: http://www.scoopweb.com/Mollisols ………….. 2/3/2013
TANAH MOLLISOLS
Subordo pada Mollisols
1. Albolls — wet soils; aquic soil moisture
regime with an eluvial horizon
2. Aquolls — wet soils; aquic soil moisture
regime
3. Cryolls — cold climate; frigid or cryic soil
temperature regime
4. Gelolls — Iklim sangat dingin; Rataan
tahunan suhu tanah < 0°C
5. Rendolls — bahan induknya kapur
6. Udolls — humid climate; udic moisture
regime
7. Ustolls — Iklim subhumid climate;
Rezim lengas-tanahnya USTIK
8. Xerolls — Iklim Mediteranaean; Rezim
lengas-tanahnya XERIK.
Diunduh dari: http://www.scoopweb.com/Mollisols ………….. 2/3/2013
TANAH MOLLISOLS
Torrertic Paleustoll (fine, mixed, superactive, thermic)
This profile was photographed in Potter County, Texas. The soil is
formed in Pleistocene age calcareous sediments on a nearly level
slope. Native vegetation is short prairie grasses. This profile has an 18
cm clay loam textured Ap horizon in a mollic epipedon that extends to
60 cm.
A clay texture argillic (Bt) horizon is present from 60 to 80 cm and
extends to 180 cm as a calcareous Btk horizon. The upper boundary of
calcium carbonate rich C horizon is seen at 180 cm.
The thick, reddish colored argillic horizon identifies the profile in the
‘Pale’ great group and the borderline soil moisture regime wherein
the moisture regime is dry in some or all parts for more than 180 but
less than 205 cumulative days in normal years and a COLE (coefficient
of linear extensibility) value more than 0.06 are identified by the
Torrertic subgroup, i.e. an intergrade to the suborder of Torrerts.
In addition to pasture these soils are used for both irrigated and
dryland cotton, corn, grain sorghum and winter wheat.
Diunduh dari: ………….. 2/3/2013
TANAH MOLLISOLS
Udic Paleustoll (Fine, mixed, semiactive
isohyperthermic)
This profile was photographed in Zambia, Africa. The soil is
formed in limestone derived sediment on a nearly level slope.
The site has been used as cropland for many years and there
is no record of natural vegetation.
The surface Ap horizon (0-18 cm) is clay loam in texture
below which clay content increases to between 50 and 60
percent to a depth of 180 cm.
Organic carbon content exceeds 1 percent from the surface to
a depth of 70 cm. Base saturation percentage (CEC7) exceeds
60 percent throughout the entire profile.
Tanaman utama yang dibudidayakan pada tanah ini adalah
jagung, sorghum, kedelai, kacang-buncis, Kapas dan bunga
matahari.
The clay loam Ap horizon presents some difficulty for hand
hoe cultivation but mechanized cultivation prepares better
seed bed tilth.
Diunduh dari: http://www.flickr.com/photos/soilscience/5469328594/ ………….. 2/3/2013
TANAH MOLLISOLS
Lithic Hapludoll (coarse-loamy, siliceous, active,
hyperthermic)
This profile was photographed in São Paulo state Brazil SA. The
soil is formed over calcareous sandstone at the edge, shoulder
position below a plateau covered with Oxisols formed in thick
oxidized sediments.
The lithic contact, seen in this photo at 50 cm is at the limit of
the Lithic subgroup classification.
Mollisols formed in base enriched sediments from the calcareous
sandstone also dominate the side slopes directly below this site
are thicker and classify as Typic Hapludolls and Typic Argiudolls.
Base saturation in the soils formed in and from sediments
derived from the calcareous sandstone range from 50 to 90%. In
surrounding Oxisols base saturation percentages are mostly less
than 10%.
Diunduh dari: ………….. 2/3/2013
TANAH MOLLISOLS
Typic Hapludoll (fine, mixed, active isohyperthermic)
This profile was photographed in a cultivated field in the state of Loreto,
Peru. This soil is formed in fine textured basic sediments on a 3 percent slope
under tropical rain forest vegetation.
This profile, photographed when extremely dry barely qualifies as a Mollisol
with a mollic epipedon just over 25 cm thick, consisting of moderately hard
blocky peds that are less than 30 cm in diameter.
A thin cambic horizon is seen between 25 and 35 cm. White calcium
carbonate nodules are present below 100 cm but are not present in
sufficient quantity to form a calcic horizon.
These soils are highly valued for slash and burn cultivation practiced by the
indigenous people. In contrast to the more prevalent Ultisols in the area
these soils naturally vegetate more rapidly after food crop cultivation is
abandoned, and that vegetation can be again be cut and burned in as little as
five years.
Weeds are a more significant problem in cultivated crops than on adjacent
Ultisols and are most often the reason to abandon a cultivated site after two
or three crops. Heat from burning kills weed seeds near the surface enabling
relatively weed free growth for one or two crops.
Diunduh dari: http://www.flickr.com/photos/soilscience/5140045787/in/set-72157625298727802/ ………….. 2/3/2013
TANAH MOLLISOLS
Aridic Calciustoll (coarse-loamy,
carbonatic, isohyperthermic)
This profile was photographed in Ponce
District, Puerto Rico.
This soil is formed in colluvium and residuum
weathered from soft limestone bedrock on a
10 percent slope.
The profile has a 30 cm mollic epipedon over a
calcic (Bk) horizon at a depth of 35 to 70 cm.
The calcic horizon is enriched in carbonate but
the parent material C horizon below 70 cm is
also calcareous.
The natural grassland vegetation is pastured.
Diunduh dari: http://www.flickr.com/photos/soilscience/5140644166/in/set-72157625298727802/ ………….. 2/3/2013
TANAH MOLLISOLS
Udic Argiustoll (fine-silty, mixed, active,
mesic)
This quarry exposure was photographed in Lancaster
County, Nebraska.
The soil is formed in loess, to a depth of about 150 cm
over glacial till.
The till is unoxidized, grey color except around oxidized
cracks that are filled with white CaCO3 illuviated from
the solum.
No plow layer is evident at this site but these soils are
extensively used for corn and small grains. However,
unreliable rainfall during the summer growing season
threatens yields in most years unless supplemental
irrigation is available.
Diunduh dari: http://www.flickr.com/photos/soilscience/5140640476/in/set-72157625298727802/ ………….. 2/3/2013
TANAH MOLLISOLS
Typic Argiustoll
southeastern South Dakota
This profile illustrates the typical morphology associated
with soils formed under grassland vegetation in the central
Great Plains region. The thick, dark A horizon has developed
as a result of the proliferation and subsequent
decompostion of fine and very fine roots. This process is
known as melanization.
Mean annual precipitation is ~22", and secondary
carbonates are clearly visible as the white nodules in the
subsoil. Secondary carbonates are those that have been
translocated in the profile and re-precipitated in discrete
forms such as nodules, concretions, masses, and coatings on
ped faces and pore linings.
Kalau CaCO3 telah tercuci dari bagian-atas profil tanah,
pergerakan dan akumulasi liat menghasilkan epembentukan
horison Bt argilik.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_05.htm………….. 2/3/2013
TANAH MOLLISOLS
Fine-silty, mixed, superactive, mesic
Oxyaquic Argixeroll
(Southwick series)
This soil belongs to the Southwick series and has
developed in loess under ponderosa pine forest. The
relatively open canopy and dense understory associated
with ponderosa pine forest in this area are responsible
for development of a mollic epipedon.
The A-Bw horizon sequence has formed mostly in
Holocene loess while the Btb horizon represents the
upper part of a late-Wisconsinan paleosol.
The Btb horizon is hydraulically restrictive with a
saturated hydraulic conductivity of ~0.1 cm/day. Water is
perched above this horizon for a period extending from
late November through May.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_16.htm………….. 2/3/2013
TANAH MOLLISOLS
Loamy-skeletal, mixed, superactive, mesic Lithic
Argixeroll
(Gwin series)
This soil formed in loess mixed with basalt colluvium.
The Bt horizons contain 27 to 35% clay. This is due to a long
period of soil formation on a stable land surface. The
percentage of coarse fragments in these soils is generally
greater than 35%.
The high percentage of coarse fragments and the
shallowness of the soil, limit the total available water
holding capacity to around 1.5-3 inches.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_10.htm ………….. 2/3/2013
TANAH MOLLISOLS
Loamy-skeletal, mixed, superactive, mesic Lithic Argixerolls
TYPICAL PEDON: Gwin cobbly silt loam, rangeland (Colors are for dry soil
unless otherwise noted)
A : 0 - 5 inches; dark grayish brown (10YR 4/2) cobbly silt loam, very dark
brown (10YR 2/2) moist; moderate to strong granular and weak thin platy
structure; slightly hard, friable, slightly sticky and slightly plastic; many roots;
20 percent angular rock fragments; neutral (pH 6.6); clear smooth boundary.
(2 to 8 inches thick)
Bt1: 5 - 12 inches; dark grayish brown (10YR 4/2) very cobbly silty clay loam,
very dark brown (10YR 2/2) moist; moderate coarse prismatic and moderate
coarse subangular blocky structure; hard, firm, moderately sticky and
moderately plastic; many roots; many fine continuous tubular pores; few
faint clay films on vertical and horizontal faces of peds; 55 percent angular
rock fragments; neutral (pH 6.6); gradual wavy boundary. (4 to 9 inches thick)
Bt2 :12 - 17 inches; brown (7.5YR 4/2) extremely cobbly silty clay loam, dark
brown (7.5YR 3/2) moist; moderate medium subangular blocky structure;
hard, firm, moderately sticky and moderately plastic; few roots; few faint
black (10YR 2/1) clay films on faces of peds and rock fragments; 60 percent
angular rock fragments; neutral (pH 6.6); gradual wavy boundary. (0 to 12
inches thick)
R : 17 inches; batuan basalt.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_10.htm ………….. 2/3/2013
TANAH MOLLISOLS
TYPE LOCATION: Walla Walla County, Washington; on Black Snake Ridge;
SW1/4SW1/4 section 3, T. 7 N., R. 38 E.
KARAKTERISTIK
Mean annual soil temperature is about 47 to 54 degrees F. These soils are
usually moist, but are dry in the moisture control section for 60 to 75
consecutive days following summer solstice but range to 45 days in western
Idaho (xeric moisture regime). The solum thickness and depth to bedrock
range from 10 to 20 inches. The particle-size control section contains 40 to
90 percent gravel, cobbles, and stones, and 15 to 35 percent clay. The soils
are slightly acid to slightly alkaline. Hue is 10YR or 7.5YR throughout.
The A horizon has value of 3 through 5 dry. 2 or 3 moist, through and
chroma of 1 through 6 dry, 1 through 3 moist, through. It has weak to strong
structure.
The BA horizon, when present, has colors similar to the A horizon, but has
textures and rock fragments similar to the Bt horizon.
The Bt horizon has value of 3 through 6 dry, 2 through 4 moist, through, and
chroma of 1 through 6 dry, and 1 through 4 moist.. It is heavy silt loam,
loam, clay loam or silty clay loam and has 35 to 90 percent rock fragments.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_10.htm ………….. 2/3/2013
TANAH MOLLISOLS
TATANAN GEOGRAFI
These soils are on mountain slopes, basalt plateaus, ridgetops, foothills,
structural benches, hill shoulders, summits, backslopes, and footslopes
and canyon walls. They formed in colluvium and residuum from basalt
mixed with loess.
Slopes are 0 to 90 percent. Elevations range from 1,600 to 4,500 feet in
Washington, and from 800 to 6,210 feet in Oregon and Idaho. Highest
elevations are on south aspects only. The climate can be characterized by
cool, wet winters and hot, dry summers.
Mean annual precipitation ranges from 14 to 24 inches in Washington, 14
to 33 inches in Idaho, and 14 to 28 inches in Oregon. Mean January
temperature is 25 to 29 degrees F; mean July temperature is 66 to 72
degrees F; and mean annual temperature is 43 to 52 degrees F. Frost-free
season is 90 to 180 days.
DRAINAGE dan PERMEABILITAS
Well drained, slow to very rapid runoff, moderately slow permeability.
PENGGUNAAN & VEGETASI
The Gwin soil is used for grazing and as wildlife habitat. Native vegetation
is mainly bluebunch wheatgrass, Idaho fescue, and Sandberg bluegrass.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_10.htm ………….. 2/3/2013
TANAH MOLLISOLS
Horison penciri dan sifat-sifat khas yg dikenali pada
pedon ini :
1. Epipedon Molik - from the surface to 17 inches (A,
Bt1 and Bt2 horizons)
2. Horison Argillic - from 5 to 17 inches (Bt1 and Bt2
horizon)
3. Lithic contact - at 17 inches (R horizon)
4. Particle-size control section - from 5 to 17 inches
(Bt1 and Bt2 horizons)
5. Rezim lengas-tanah Xerik
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_10.htm ………….. 2/3/2013
TANAH MOLLISOLS
Fine-silty, mixed, superactive, mesic Typic
Argiudoll
(Sharpsburg series)
Tanah-tanah ini nterbentuk pada bahan induk loess yang dalam
(tebal) di bawah vegetasi prairie rumput-tinggi.
They are extensive throughout SW Iowa, NW Missouri, NE
Kansas, and SE Nebraska, where they occupy convex ridgetops,
upland divides, convex side slopes, and high benches. Most of
these soils are now used for cultivation of corn, soybeans, small
grains, and hay.
Mean annual precipitation is approximately 28-32", which has
been sufficient to leach CaCO3 from the soil profile.
This has allowed clay movement and formation of an argillic
horizon (Bt horizons).
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_03.htm ………….. 2/3/2013
TANAH MOLLISOLS
TAXONOMIC CLASS: Fine, smectitic, mesic Typic Argiudolls
TYPICAL PEDON: Sharpsburg silty clay loam, on a convex slope of 8 percent, in a cultivated
field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 20 centimeters; black (10YR 2/1) silty clay loam, dark grayish brown (10YR 4/2)
dry; weak fine subangular blocky structure; friable; few fine roots; slightly acid; abrupt
smooth boundary.
A1--20 to 28 centimeters; very dark brown (10YR 2/2) silty clay loam, dark grayish brown
(10YR 4/2) dry; moderate very fine subangular blocky structure; friable; slightly acid; clear
smooth boundary.
A2: 28 - 43 cm; very dark grayish brown (10YR 3/2) silty clay loam, grayish brown (10YR
5/2) dry; some brown (10YR 4/3) peds; moderate very fine subangular blocky structure;
friable; moderately acid; gradual smooth boundary. (Combined thickness of the A horizon
is 25 to 49 centimeters.)
Bt1: 43 - 61 cm; brown (10YR 4/3) silty clay loam; moderate fine subangular blocky
structure parting to weak fine subangular blocky; firm; very few fine roots; common
distinct very dark grayish brown (10YR 3/2) clay films on faces of peds; very dark gray
(10YR 3/1) organic stains on faces of peds; moderately acid; gradual smooth boundary.
Bt2: 61 - 79 cm; brown (10YR 4/3) and yellowish brown (10YR 5/4) silty clay loam; weak
medium prismatic structure parting to moderate fine subangular blocky; firm; very few
fine and medium roots; many distinct dark grayish brown (10YR 4/2) clay films on faces of
peds; few fine iron and manganese oxide concretions; few fine distinct light brownish gray
(2.5Y 6/2) redoximorphic depletions; moderately acid; gradual smooth boundary.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_03.htm ………….. 2/3/2013
TANAH MOLLISOLS
Bt3: 79 - 97 cm; brown (10YR 5/3) silty clay loam; weak medium
prismatic structure parting to weak medium subangular blocky; friable;
many prominent grayish brown (10YR 5/2) clay films on faces of peds;
few fine iron and manganese oxide concretions; common medium faint
light brownish gray (2.5Y 6/2) redoximorphic depletions; common
medium prominent strong brown (7.5YR 5/6) redoximorphic
concentrations; moderately acid; gradual smooth boundary. (Combined
thickness of the Bt horizon is 50 to 100 centimeters.)
BC: 97 - 117 cm; yellowish brown (10YR 5/4) silty clay loam; weak
medium prismatic structure; firm; common distinct grayish brown
(10YR 5/2) clay films on faces of peds; few fine iron and manganese
oxide concretions; many fine and medium distinct grayish brown (2.5Y
5/2) redoximorphic depletions; common medium prominent strong
brown (7.5YR 5/8) redoximorphic concentrations; moderately acid;
gradual smooth boundary. (10 to 25 centimeters thick)
C : 117 - 152 cm; mottled grayish brown (2.5Y 5/2), yellowish brown
(10YR 5/4), and brown (7.5YR 4/4) silty clay loam; massive; firm; very
few fine roots; common fine iron and manganese oxide concretions;
slightly acid.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_03.htm ………….. 2/3/2013
TANAH MOLLISOLS
RANGE IN CHARACTERISTICS:
RANGE IN CHARACTERISTICS:
Thickness of the mollic epipedon--25 to 49
centimeters
Depth to carbonates -- >150 cm
Clay content in the particle-size control
section (weighted average)--36 to 42
percent
Sand content in the particle-size control
section (weighted average)--less than 5
percent
Bt horizon (lower part) or Btg (if present):
Hue: 7.5YR to 5Y; Value: 4 to 6; Chroma: 2
to 6
Texture--silty clay loam
Clay content--30 to 38 percent clay
Sand content--less than 5 percent
Reaction--moderately acid or slightly acid
Ap and A horizons:
Hue: 10YR; Value: 2 or 3; Chroma: 1 to 3
Texture--silt loam or silty clay loam
Clay content--25 to 34 percent clay
Sand content--less than 5 percent
Reaction--strongly acid to slightly acid
BC or BCg horizon (if present):
Hue: 7.5YR to 5Y; Value: 4 to 6; Chroma: 2
to 6
Texture--silty clay loam
Clay content--28 to 35 percent clay
Sand content--less than 5 percent
Reaction--moderately acid to neutral
Bt horizon (upper part):
Hue: 10YR; Value: 4 or 5; Chroma: 3 or 4
Texture--silty clay loam or silty clay
Clay content : 36 to 42 percent
Sand content : less than 5 percent
Reaction--strongly acid to slightly acid
Matrix value and chroma of 5/2 and 6/2
within depths of less than 80 centimeters
are outside the range of the series
C or Cg (if present) horizon:
Hue: 7.5YR to 5Y; Value: 4 to 6; Chroma: 2
to 6
Texture--silty clay loam or silt loam
Clay content--25 to 35 percent clay
Sand content--less than 5 percent
Reaction--moderately acid to neutral
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_03.htm ………….. 2/3/2013
TANAH MOLLISOLS
GEOGRAPHIC SETTING:
1. Bahan induk tanah: loess
2. Landscape--dissected till plains and stream terraces
3. Landform--interfluves and side slopes on dissected till
plains and on treads and risers on stream terraces in river
valleys
4. Bentuk lereng: convex (cembung)
5. Hillslope position--summit and back slope
6. Geomorphic component--interfluve, side slope, and tread
and riser
7. Kemiringan : 0 - 18 %
8. Elevation: 200 - 400 m above sea level
9. Mean annual air temperature--8 to 17 degrees C
10. Mean annual precipitation--660 to 1,145 millimeters
11. Periode bebas salju: 155 - 255 hari.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_03.htm ………….. 2/3/2013
TANAH MOLLISOLS
PERHATIAN:
1. Particle-size control section--the zone from a depth of 43 to
93 centimeters;
series control section--the zone from the surface to a depth
of 150 centimeters.
2. Horison penciri dan sifat-sifat yg dikenali dalam pedon ini :
Epipedon molik : the zone from the surface of the soil to a
depth of 43 centimeters (Ap, A1, and A2 horizons);
Horison argilik: the zone from a depth of 43 to 97
centimeters (Bt1, Bt2, and Bt3 horizons);
Rezim lengas tanah UDIK.
3. Redoximorphic features above a depth of 100 centimeters
are believed to be related to precipitation events in
abnormal years.
4. Ketebalan horison A, depth to clay maximum, maximum
percent clay, thickness of the Bt horizon, and depth to
redoximorphic features decrease as gradient increases on
convex slopes.
Diunduh dari: http://www.cals.uidaho.edu/soilorders/mollisols_03.htm ………….. 2/3/2013
TANAH MOLLISOLS
The Drummer series consists of very deep, poorly
drained soils formed in loess or other silty material and
in the underlying loamy stratified outwash on nearly
level or depressional parts of outwash plains, stream
terraces, and till plains. Slope ranges from 0 to 2
percent. Mean annual precipitation is about 940 mm (37
inches), and mean annual air temperature is about 11
degrees C (52 degrees F).
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
TANAH MOLLISOLS
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Typic Endoaquolls
TYPICAL PEDON: Drummer silty clay loam - on a south-facing concave slope
with less than 1 percent gradient under grass at an elevation of about 218
meters (715 feet) above mean sea level. (Colors are for moist soil unless
otherwise stated.)
Ap--0 to 18 cm (0 to 7 inches); black (10YR 2/1) silty clay loam, dark gray
(10YR 4/1) dry; weak fine granular structure; firm; many fine roots;
moderately acid; clear smooth boundary.
A--18 to 36 cm (7 to 14 inches); black (10YR 2/1) silty clay loam, dark gray
(10YR 4/1) dry; moderate fine subangular blocky structure parting to weak
fine granular; firm; many fine and medium roots throughout; slightly acid;
clear smooth boundary. [Combined thickness of the A horizons is 25 to 56 cm
(10 to 22 inches)].
BA--36 to 48 cm (14 to 19 inches); very dark gray (10YR 3/1) silty clay loam,
gray (10YR 5/1) dry; moderate fine and medium subangular blocky structure;
firm; many fine and medium roots; few fine faint very dark grayish brown
(2.5Y 3/2) masses of oxidized iron-manganese in the matrix; slightly acid;
gradual smooth boundary. [0 to 20 cm (0 to 8 inches) thick]
……..
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
TANAH MOLLISOLS
Bg--48 to 64 cm (19 to 25 inches); dark gray (10YR 4/1) silty clay loam;
moderate fine prismatic structure parting to moderate fine angular
blocky; firm; many fine roots; common fine distinct and prominent
yellowish brown (10YR 5/6) masses of oxidized iron in the matrix;
many worm holes; neutral; gradual smooth boundary.
Btg1--64 to 81 cm (25 to 32 inches); grayish brown (2.5Y 5/2) silty clay
loam; weak fine and medium prismatic structure parting to moderate
fine angular blocky; firm; many fine roots; common distinct dark gray
(N 4/0) clay films on faces of peds; many medium distinct yellowish
brown (10YR 5/4) masses of oxidized iron-manganese in the matrix;
neutral; gradual wavy boundary.
Btg2--81 to 104 cm (32 to 41 inches); gray (N 5/0) silty clay loam; weak
medium prismatic structure parting to weak medium angular blocky;
firm; few fine roots; few distinct dark gray (N 4/0) clay films on faces of
peds; many medium prominent yellowish brown (10YR 5/4) masses of
oxidized iron-manganese in the matrix; neutral; clear wavy boundary.
[Combined thickness of the Bg horizon and Btg horizons is 51 to 119
cm (20 to 47 inches).]
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
TANAH MOLLISOLS
2Btg3--104 to 119 cm (41 to 47 inches); gray (N 5/0)
loam; weak coarse subangular blocky structure; friable;
few fine roots; few distinct dark gray (10YR 4/1) clay
films on faces of peds; common medium prominent
yellowish brown (10YR 5/6) masses of oxidized iron in
the matrix; 4 percent fine gravel; neutral; abrupt wavy
boundary. [10 to 25 cm (4 to 10 inches) thick]
2Cg--119 to 152 cm (47 to 60 inches); dark gray (10YR
4/1) stratified loam and sandy loam; massive; friable;
many medium prominent olive brown (2.5Y 4/4) masses
of oxidized iron-manganese in the matrix; many medium
distinct gray (N 5/0) iron depletions in the matrix;
slightly alkaline.
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
TANAH MOLLISOLS
RANGE IN CHARACTERISTICS:
The depth to the base of soil development ranges from 102 to 165 cm (40 to 65
inches). The depth to horizons with greater than 15 percent sand ranges from
102 to 152 cm (40 to 60 inches). The dominant clay mineral in the upper part of
the series control section is smectite and in the lower part is illite. The particlesize control section averages between 20 and 35 percent clay and less than 15
percent fine sand or coarser. The mollic epipedon ranges from 25 to 61 cn (10
to 24 inches) in thickness and extends into the upper part of the B horizon in
many pedons. Rock fragments are less than 15 percent in the lower part of the
series control section. Depth to carbonates is greater than 102 cm (40 inches).
The Ap, A, and/or AB horizon has hue of 10YR, 2.5Y, 5Y, or is neutral;
value of 2 to 3; and chroma of 0 to 2. It is silty clay loam and less
commonly is silt loam. Clay content ranges from 20 to 35 percent.
Reaction ranges from moderately acid to slightly alkaline.
Some pedons have an AB horizon rather than a BA horizon.
The Bg, Btg, and/or BA horizon has hue of 10YR, 2.5Y, 5Y, or is neutral;
value dominantly of 4 or 5, but ranges to 3 in the upper part and to 6
in the lower part; and chroma dominantly of 1 or 2, but ranging from
0 to 4. Texture is silty clay loam in the upper part and silty clay loam
or silt loam in the lower part. Clay content ranges from 20 to 35
percent. Reaction ranges from moderately acid to slightly alkaline.
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
TANAH MOLLISOLS
RANGE IN CHARACTERISTICS:
The 2Bg, 2Btg, and/or 2BCg horizon has hue of 7.5YR, 10YR, 2.5Y,
5Y, or is neutral; value of 4 to 6; and chroma of 0 to 2. Some
pedons have nearly equal proportions of low chroma and high
chroma colors in the matrix. Texture is commonly loam or silt
loam, and most pedons contain strata of sandy loam, clay loam,
silty clay loam, sandy clay loam, or fine sandy loam. Clay content
ranges from 15 to 33 percent and sand content ranges from 15 to
55 percent. Content of rock fragments is less than 7 percent.
Reaction ranges from slightly acid to moderately alkaline.
The 2Cg and/or 2C horizon has hue of 7.5YR, 10YR, 2.5Y, 5Y, or is
neutral; value of 4 to 7; and chroma of 0 to 8. It typically is
stratified. Textures include loam, sandy loam, sandy clay loam,
clay loam, silt loam, and silty clay loam. Some pedons have thin
strata of loamy sand. Clay content ranges from 10 to 32 percent
and sand content ranges from 15 to 80 percent. Content of rock
fragments is less than 15 percent. Reaction ranges from neutral
to moderately alkaline.
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
TANAH MOLLISOLS
GEOGRAPHIC SETTING:
Drummer soils are on nearly level or depressional parts of outwash
plains, stream terraces, and till plains of Wisconsinan Age. Slope
ranges from 0 to 2 percent. Drummer soils formed in 40 to 60 inches
of loess or other silty material and in the underlying loamy stratified
outwash. Mean annual air temperature ranges from 46 to 54 degrees
F., mean annual precipitation is 29 to 40 inches, frost free days range
from 140 to 180 days, and the elevation ranges from 500 to 1020 feet
above mean sea level.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Poorly drained. In drained conditions, an apparent seasonal high water
table is 15 cm (0.5 foot) above the surface to 31 cm (1.0 foot) below
the surface at some time between January and May in most years. In
undrained conditions, an apparent seasonal high water table is 15 cm
(0.5 foot) above the surface to 15 cm (0.5 foot) below the surface at
some time between November and June in most years. The potential
for surface runoff is negligible to low. Water ponds on these soils for
brief periods during the spring. Saturated hydraulic conductivity is
moderately high to high (4.23 to 14.11 micrometers per second).
Permeability is moderate.
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
TANAH MOLLISOLS
USE AND VEGETATION:
Most areas are cropped. Corn and soybeans are the
principal crops. Some areas are used for growing small
grain or meadow. Native vegetation is hydrophytic grasses,
reeds, and sedges.
SERIES ESTABLISHED: Ford County, Illinois, 1929.
Horison penciri dan sifat-sifat pada pedon ini:
1. mollic epipedon - the zone from the surface to a depth
of 48 cm (19 inches) (Ap, A, and BA horizons);
2. cambic horizon - the zone from approximately 48 to
119 cm (19 to 47 inches) (Bg, Btg1, Btg2, and 2Btg3
horizons);
3. aquic conditions - redoximorphic features present in
the zone from approximately 36 to 152 cm (14 to 60
inches) (BA, Bg, Btg1, Btg2, 2Btg3, and 2Cg horizons).
ADDITIONAL DATA: SSIR No. 19, pp. 92-109. University of Illinois
Agricultural Experiment Station Bulletin 665, Profile No. 29.
Diunduh dari: https://soilseries.sc.egov.usda.gov/OSD_Docs/D/DRUMMER.html ………….. 4/3/2013
PENGELOLAAN MOLLISOLS
Even the most fertile Mollisols cannot sustain high crop production
and harvest without fertilization.
While native fertility will maintain moderate levels of crop production for several years,
high levels of production require additional fertility .
Note that by about 1920 fertilizer was required for a lesser yield on Ultisols while no
fertilizer was used to obtain a greater yield on Mollisols.
By about 1980 the use of fertilizer had increased on both soils but the Mollisols required
higher annual fertilizer rates than the Ultisols because higher yield averages were
maintained. Although lime is usually not initially required for crop production and was not
used in 1919 it is now often necessary to maintain crop production on most Mollisols.
A portion of the success of initial food crop growth on Mollisols can be attributed to the
mineralization of organic carbon with release of organically bound nitrogen as the soils are
cultivated and exposed to higher maximum soil temperatures.
The presence of fertile subsoil, free of aluminum toxicity and thus unhindered root
penetration is a major contributor to the excellence of Mollisols for crop production.
Diunduh dari: http://courses.soil.ncsu.edu/ssc551/units/print/unit20.html………….. 4/3/2013
PENGELOLAAN MOLLISOLS
Mollisols dapat dikelola sebagai
sawah produktif …………..
bgm caranya?
Foto: smno.sawah.nganjuk.janu2013