Judul: Perubahan Fraksi Fosfor Lambat Tersedia pada Tanah Tergenang yang Diameliorasi Bahan Organik
Abstrak: The low availability and easily fixed phosphorus (P) in soil resulted in heavy and continuous P fertilization by farmers, leading to accumulation of residue-P in soil. In such condition, further P fertilization will not result in higher plant productivity known as leveling off. One way to increase the availability of residual P in soil is to add organic matter. There are various forms of P in the soil, from soluble to unavailable phosphorus can also be differenciated as inorganic and organic forms, where the sum of both referred as total-P. The objective of this research was to study the changes of slow-available phosphorus fraction in a submerged soil ameliorated with organic matter effect of organic matter (extracted with 0.1 M NaOH). Research unit was 200 g (oven-dry, 105°C) in a 10 cm pot. The soil was treated with 0, 500, 750, 1000, 2000, and 5000 kg/ha, and submerged for 5 weeks. Every week for 5 weeks, subsample of each research unit was extracted for determination of NaOH-P following Tiessen and Moir 1993 procedure. The results showed that in general NaOH-Pi, NaOH-Po, and NaOH-Pt increase with increasing organic matter treatments. There was a dynamic pattern of NaOH-Pt, NaOH-Pi, and NaOH-Po with the time of submersion, in which in general NaOH-P initially decreased, increased, then finally decreased.
Keyword: Bogor Agricultural University (IPB), Submerged Soil., Organic Matter, NaOH-Pt, NaOH-Po, NaOH-Pi

Judul: Pengaruh Bahan Organik terhadap Eh dan pH, serta Korelasinya terhadap P pada Tanah yang Digenangi
Abstrak: Prolong P fertilization in intensive rice cultivation have been resulted in unavailable-residual P accumulation in the soil. Further P fertilization in such soil does not have significant effect in increasing rice productivity. Submerged ricefield is predominated by reduced condition. In order to increase the accumulated unavailable-residual P, application of organic matter as source of electron donor was studied. This research was aimed to study the effects of organic matter on Eh and pH and their correlationswith to P-availability in a submerged soil. Organic matter treatments were 0, 500, 750, 1000,2000, 5000, 10000, 20000, and 40000 kg/ha. Experimental unit was 200 g soil (105°C oven dry-weight) in a 10 cm (diameter) pot. The soil was submerged for 7 weeks, and the soil’spH, Eh, and available P were measured periodically. The available P measured included NaHCO3-P (fastly available P) and NaOH-P (slowly available P). The results in general showed that the Eh decreased, while the pH increased along withincreasing quantity of organic matter, and with submerging time. There were significant negative correlations between Eh and pH (r = 0,840**), between Eh and fastly available P (r = -0,613**), and between Eh and total available P (r = -0,561**). However, there was no significant correlation between Eh and slowly available P (r = 0,0028). Furthermore, there were no significant correlations between pH (at range of 6,3±0,2) with all forms of available P.
Keyword: Bogor Agricultural University (IPB), Submerging Time, pH, Organic Matter, Eh, Available P

Judul: Beberapa aspek anatomi alat sirkulasi ruang dada kancil
Abstrak: Telah dilakukan penelitian dengan menggunakan 10 ekor kancil dewasa jantan dan betina dengan tujuan untuk menge- tahui beberapa aspek anatomi alat sirkulasi di dalam ruang dada, meliputi jantung, pembuluh darah yang keluar dan ma- suk jantung serta ukuran-ukuran jantung. Kancil merupakan ruminansia terkecil di dunia, hidup di daerah tropika India, Thailand, Malaysia dan Indonesia bagian barat. Hewan ini dilindungi dan mempunyai prospek yang baik untuk hewan penelitian maupun dibudidayakan. Hasil penelitian menunjukkan bahwa berat jantung rаta-rata adalah 0.69% dari berat rata-rata kancil. Dan ini mirip pada jantung kuda dan anjing. Bentuk jantung lonjong seperti halnya ruminansia. Demikian pula letaknya di dalam ruang dada seperti pada ruminansia dengan adanya Ligamentum sternopericardiacum. Di dalam ventrikel kanan membersit sebuah Musculus (M.) papillaris dari dindingnya dan tiga sampai empat Musculi (Mm.) papillares dari Septum interventriculare. Hanya dua buah Mm. papillares yang berukuran besar dibersitkan dari dinding ventrikel kiri. Percabangan Arteri (A.) coronaria sinistra lebih dominan dari pada A. coronaria dextra. Sedangkan A. sub clavia sinistra dicabangkan langsung dari aorta di dorso- caudal pembersitan Truncus (Tr.) brachiocephalicus…
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