Download - DINAMIKA KALIUM DALAM TANAH
DINAMIKA KALIUM DALAM TANAH
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Dinamika K dalam Tanah
Introduction The Potassium Cycle
Forms of Potassium in soil Ketersediaan K dalam tanah
Manajemen K tanah
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
PendahuluanK is the third most likely element after nitrogen and phosphorus to limit plant productivity.
Biasanya diaplikasikan sebagai pupuk
K ada dalam larutan tanah sebagai kation K+
K tidak membentuk gas yang hilang ke udara
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Its behavior in soil is influenced more by cation exchange reactions than by microbiological processes
K tidak menyebabkan pencemaran lingkungan eksternal
K tidak toksik dan tidak menyebabkan problematik eutrofikasi
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Pendahuluan
K dalam nutrisi tanaman dan hewan
Potassium activates many enzymes in plants and animals that are responsible for energy metabolism, photosynthesis and other processes
As a component of the cytoplasm of plant cells, it helps to lower cellular osmotic water potential thereby increasing the ability of root cells to take up water.
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
K sangat penting untuk fiksasi nitrogen pada legume
Kecukupan K telah terbukti membantu tanaman beradaptasi terhadap cekaman lingkungan
In animals including humans, K is important in regulating the nervous system and maintenance of good blood vessels.
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
K dalam nutrisi tanaman dan hewan
Gejala Defisiensi K
Mengurangi kemampuan tanaman untuk beradaptasi terhadap cekamam lingkungan mis. Kekeringan, Genangan banjir, dll.
Pucuk dan tepian daun menguning (chlorosis) dan kemudian mati (nekrosis).
In some crops, K deficiency produces white necrotic spots that looks like insect damage.
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Siklus K
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Sumber Original K adalah mineral primer Mineral Mica (biotite dan muscuvite) Potassium feldspar (orthoclase dan microcline)
Potassium is released from the minerals during the weathering process
When available for plant uptake, it is taken up by plants in large quantities
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Siklus K
Dalam ekosistem alamiah, K is returned to the soil by rainwater leaching of foliage and by plant residue or as waste from animals that feed on plantPotassium is lost by soil erosion and runoff, and leaching to the groundwaterMost potassium in agricultural ecosystems are lost through removal of crops and crop residues from soil
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Siklus K
Bentuk-bentuk K dalam tanah
Empat bentuk K dalam tanah adalah:– K dalam struktur mineral primer– K dalam posisi tidak dapat ditukar dalam mineral
sekunder– K in exchangeable form on soil colloid surfaces– K ions larut dalam air
Total K in soil and its distribution as shown in the K-cycle is a function of the clay minerals present in soil
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
K dalam struktur mineral primer
Unavailable (90-98% of all soil K)
K dalam posisi tidak dapat ditukar pada mineral sekunder
Slowly available -fixed K is not easily exchangeable-In equilibrium with more available forms
K dalam bentuk dapat ditukar pada permukaan koloid tanah
Readily available (1-2% of all soil K) -90% of readily available
Ion K+ larut dalam airReadily available -Subject to leaching-Equilibrium with exchangeable form
Ketersediaan bentuk-bentuk K
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Fiksasi K oleh Koloid Tanah
Nonexchangeable-K Exchangeable-K Soil Solution-K
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Faktor Ketersediaan K dalam tanah
1. Tipe Koloid TanahAbility of various colloids to fix K varies (2:1)
2. Pembasahan & Pengeringan TanahPhysically affects the structure of colloids
3. Pembekuan & Pencairan TanahPhysically affects the structure of colloids
4. Kemasaman tanah (pH)High pH increases the fixation of K because of less H+ and
Al3+ at exchange sites.
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Problem K dalam Kesuburan Tanah
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
The main problem with managing soil K is that of converting the unavailable forms of the element to available forms Available K is usually supplemented by fertilization
Another problem is removing a lot of crops from the soil without returning the crop residues Attempts should be made to return as much residue as
possible for the natural plant-soil cycling of K to continue
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
Pengelolaan Kalium
Pengelolaan Kalium
Growing high K content plants places demand on the soil supply of potassium To have high yields of such crops, e.g., alfalfa, it needs to planned in
advance to supply soil with enough K to last the cropping season –fertilization
Pemupukan dengan dosis ringan dan sering ternyata lebih baik daripada dosis tinggi sekali aplikasi, hal ini dapat mengurangi konsumsi mewah K
Pengapuran tanah ternyata meningkatkan retensi K dalam atanah.
SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt
SUMBER: http://www.ipipotash.org/en/presentn/aspcwdb.php
Kalium TanahEfek status K-tanah thd hasil tanaman dan efisiensi pupuk N
(JOHNSTON et al., 2001)
SUMBER: http://www.ipipotash.org/en/presentn/aspcwdb.php
Kalium TanahRespon tanaman thd K dalam percobaan jangka panjang (1949-91)
(MERBACH et al., 1999)
SUMBER: http://www.ipipotash.org/en/presentn/aspcwdb.php
Kalium TanahSiklus kalium dalam sistem tanah-tanaman-ternak
(SYERS, 1998)
SUMBER: http://www.depi.vic.gov.au/agriculture-and-food/dairy/pastures-management/fertilising-dairy-pastures/what-nutrients-do-plants-require
Kalium TanahBentuk-bentuk K-tanah dan ketersediaannya bagi
tanaman.
SUMBER: http://www.ipipotash.org/en/eifc/2011/29/3
Siklus Kalium dalam TanahStatus K-tanah mempengaruhi penyerapan K
oleh akar tanaman.
Jumlah K dalam tanah
tergantung pada tipe-tanah, produksi
tanaman, retensi atau panen
biomasa residu tanaman,
pemupukan K dan irigasi.
SUMBER: Ben Zioni et al., 1971; Physiolgia Plantarum 24:288-290.
Kalium Tanah
Penyerapan NO3
- oleh akar tanaman
dikendalikan oleh hasil
reduksi NO3-
dalam tanaman dan
siklus K+ dalam
tanaman.
SUMBER: http://www.intechopen.com/books/soil-processes-and-current-trends-in-quality-assessment/potassium-in-soils-of-glacial-origin
Kalium TanahModel mineral liat tipe 1:2 (illite) yang menunjukkan
posisi penjerapan K+
Kalium Tanah
SUMBER: http://www.intechopen.com/books/soil-processes-and-current-trends-in-quality-assessment/potassium-in-soils-of-glacial-origin
Model pelepasan K dalam proses pelapukan mineral primer tanah
SUMBER: http://people.umass.edu/psoil120/guide/chapter7.htm
Kalium TanahKesetimbangan bentuk-bentuk K dalam tanah.
SUMBER: http://www.cropnutrition.com/efu-potassium#in-soil
Siklus Kalium TanahSekitar 90 -98 % total K dalam tanah dalam bentuk ineral primer
tidak-larut, mineral ini thaan terhadap pelpaukan kimiawi. Pelepasan K dari mineral primer ini sangat lambat, dan jumlahnya sangat kecil
dibandingkan dnegan kebutuhan tanaman.
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Kalium Tanah
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Kalium Tanah
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Kalium TanahModel of freeing potassium in the sequence of weathering
processes the primary soil minerals