DINAMIKA KALIUM DALAM TANAH SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎

Forms of Potassium in soil 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

SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎ Pendahuluan K 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

SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎ Pendahuluan 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

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 dalam nutrisi tanaman dan hewan 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

SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎ 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

SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎ Siklus K SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎

SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎ Siklus K 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

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 plant Potassium is lost by soil erosion and runoff, and leaching to the groundwater Most 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

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

Ketersediaan bentuk-bentuk K 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 air Readily available Subject to leaching Equilibrium with exchangeable form 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 Tipe Koloid Tanah Ability of various colloids to fix K varies (2:1) Pembasahan & Pengeringan Tanah Physically affects the structure of colloids Pembekuan & Pencairan Tanah 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

SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎ Pengelolaan Kalium 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

SUMBER: myspace.aamu.edu/users/monday.mbila/soils/SPS251Lecture15.ppt‎ 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 Tanah Efek status K-tanah thd hasil tanaman dan efisiensi pupuk N (JOHNSTON et al., 2001) SUMBER: http://www.ipipotash.org/en/presentn/aspcwdb.php ‎

SUMBER: http://www.ipipotash.org/en/presentn/aspcwdb.php ‎ Kalium Tanah Respon tanaman thd K dalam percobaan jangka panjang (1949-91) (MERBACH et al., 1999) SUMBER: http://www.ipipotash.org/en/presentn/aspcwdb.php ‎

Kalium Tanah Siklus kalium dalam sistem tanah-tanaman-ternak (SYERS, 1998) SUMBER: http://www.ipipotash.org/en/presentn/aspcwdb.php ‎

Bentuk-bentuk K-tanah dan ketersediaannya bagi tanaman. Kalium Tanah Bentuk-bentuk K-tanah dan ketersediaannya bagi tanaman. SUMBER: http://www.depi.vic.gov.au/agriculture-and-food/dairy/pastures-management/fertilising-dairy-pastures/what-nutrients-do-plants-require ‎

Siklus Kalium dalam Tanah Status 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: http://www.ipipotash.org/en/eifc/2011/29/3 ‎

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: Ben Zioni et al., 1971; Physiolgia Plantarum 24:288-290.

Kalium Tanah Model mineral liat tipe 1:2 (illite) yang menunjukkan posisi penjerapan K+ 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 Kalium Tanah Model pelepasan K dalam proses pelapukan mineral primer tanah SUMBER: http://www.intechopen.com/books/soil-processes-and-current-trends-in-quality-assessment/potassium-in-soils-of-glacial-origin ‎

Kalium Tanah Kesetimbangan bentuk-bentuk K dalam tanah. SUMBER: http://people.umass.edu/psoil120/guide/chapter7.htm ‎

SUMBER: http://www.cropnutrition.com/efu-potassium#in-soil ‎ Siklus Kalium Tanah Sekitar 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. SUMBER: http://www.cropnutrition.com/efu-potassium#in-soil ‎

Kalium Tanah SUMBER: ‎

Kalium Tanah SUMBER: ‎

Kalium Tanah Model of freeing potassium in the sequence of weathering processes the primary soil minerals SUMBER: ‎