Kajian Ketersediaan P Di Ultisol Akibat Pemberian Bahan Organik
ABSTRAK
Analisis laboratorium untuk mengkaji penyediaan Fosfat (P) di Tanah
Ultisol akibat pemberian bahan organik. Penelitian ini didesain menggunakan
rancangan acak lengkap, menginkubasikan tiga jenis bahan organik; kompos;
pupuk kandang ayam dan pupuk hijau dengan dosis 0; 5; 10 dan 15 ton/ha
sebanyak tiga ulangan. Diinkubasi selama 20 hari dan senantiasa dalam keadaan
kapasitas lapang. Parameter yang diamati adalah pH H2O, kadar C-organik, Ptersedia, P-larut, P-Al, P-Fe dan P-total tanah.
Hasil analisis menunjukkan bahwa pemberian bahan organik
meningkatkan nilai pH, kadar C-organik, P-tersedia dan P-larut tanah tetapi
menurunkan kadar P-Al dan P-Fe tanah dan tidak berpengaruh pada kadar P-total
tanah. Penyediaan P di tanah Ultisol akibat pemberian bahan organik berasal dari
P-Al dan P-Fe yang bebas. Pupuk hijau lamtoro (Leucaena leucocephala) lebih
baik dari kompos dan pupuk kandang ayam dalam menyediakan P-tersedia.
Kata Kunci: Bahan organik, Fosfat, Ultisol
4
Universitas Sumatera Utara
ABSTRACT
Laboratory analysis to study the availability of Phosphate (P) in Ultisols
by organic matters application. This study was designed using a complete
randomized design, three of organic matters; compost; chicken manure and green
manure was applicated to the Ultisols, with dosages 0; 5; 10 and 15 ton/ha, this
study replicated three times. Incubated for 20 days and always in field capacity.
Parameters measured were soil pH H2O, organic-C, available-P, soluble-P, Al-P,
Fe-P and total-P.
The result of analysis showed that the application of organic matters
increases the pH value, levels of organic-C, available-P and soluble-P but
decreases levels of Al-P and Fe-P. There was no significance in total soil P levels.
Avaibility of P in the Ultisols due to the application of organic matters released
from the Al-P and Fe-P. The green manure lamtoro (Leucaena leucocephala) is
better than compost and chicken manure in released available-P.
Keywords: Organic matter, Phosphate, Ultisols.
5
Universitas Sumatera Utara
Analisis laboratorium untuk mengkaji penyediaan Fosfat (P) di Tanah
Ultisol akibat pemberian bahan organik. Penelitian ini didesain menggunakan
rancangan acak lengkap, menginkubasikan tiga jenis bahan organik; kompos;
pupuk kandang ayam dan pupuk hijau dengan dosis 0; 5; 10 dan 15 ton/ha
sebanyak tiga ulangan. Diinkubasi selama 20 hari dan senantiasa dalam keadaan
kapasitas lapang. Parameter yang diamati adalah pH H2O, kadar C-organik, Ptersedia, P-larut, P-Al, P-Fe dan P-total tanah.
Hasil analisis menunjukkan bahwa pemberian bahan organik
meningkatkan nilai pH, kadar C-organik, P-tersedia dan P-larut tanah tetapi
menurunkan kadar P-Al dan P-Fe tanah dan tidak berpengaruh pada kadar P-total
tanah. Penyediaan P di tanah Ultisol akibat pemberian bahan organik berasal dari
P-Al dan P-Fe yang bebas. Pupuk hijau lamtoro (Leucaena leucocephala) lebih
baik dari kompos dan pupuk kandang ayam dalam menyediakan P-tersedia.
Kata Kunci: Bahan organik, Fosfat, Ultisol
4
Universitas Sumatera Utara
ABSTRACT
Laboratory analysis to study the availability of Phosphate (P) in Ultisols
by organic matters application. This study was designed using a complete
randomized design, three of organic matters; compost; chicken manure and green
manure was applicated to the Ultisols, with dosages 0; 5; 10 and 15 ton/ha, this
study replicated three times. Incubated for 20 days and always in field capacity.
Parameters measured were soil pH H2O, organic-C, available-P, soluble-P, Al-P,
Fe-P and total-P.
The result of analysis showed that the application of organic matters
increases the pH value, levels of organic-C, available-P and soluble-P but
decreases levels of Al-P and Fe-P. There was no significance in total soil P levels.
Avaibility of P in the Ultisols due to the application of organic matters released
from the Al-P and Fe-P. The green manure lamtoro (Leucaena leucocephala) is
better than compost and chicken manure in released available-P.
Keywords: Organic matter, Phosphate, Ultisols.
5
Universitas Sumatera Utara