Judul: Mempelajari Pengaruh Pengolahan Tanah terhadap Tahanan Penetrasi Tanah di Kebun Percobaan Darmaga IV IPB, Bogor
Abstrak: Tujuan penelitian ini adalah untuk mempelajai pengaruh pengelolaan tanah khususunya metoda pengolahan tanah terhadap tahanan penetrasi tanah, serta mengetahui hubungan antara kadar air tanah dan bulk density tanah dengan tahanan penetrasi tanah.
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Judul: Dinamika Penetrabilitas Tanah pada Berbagai Penggunaan Lahan di Tanah Latosol, Darmaga
Abstrak: Plant roots that functioning to absorb water and nutrients can be inhibited when soil penetrabilty is quite high. Soil penetrability can be affected by soil properties, for example texture, bulk density, organic matter content, soil water content, matrix potential, calcium carbonate, and types of clay mineral. Of the soil properties, there are some that can be influenced by the type of land use. This study examined the penetrability of soil in various land uses. There was a series of observation of soil penetrability and soil properties in a variety of land use conducted in this research in order to study the relationship of soil properties on soil penetration resistance, soil water content relationship with penetrability, and resistance dynamics of land penetration in various land uses. The results showed that the soil texture class in the three land uses was clay. The highest clay percentage was found in grasslands both in the depth of 0-10 cm (82.00%) and 10-20 cm (81.90%). The highest soil bulk density in the depth of 0-10 cm was found in grasslands (1.09 g/cm3) and in the depth of 10-20 cm was found in mixed farms (1.13 g/cm3). The organic matter content in the depth of 0-10 cm was found in mixed farms (4.80%) and in the depth of 10-20 cm was found in secondary forest (3.18%). The index of soil aggregate stability of the three land uses were classified as a very stable class. Soil total pore space in the depth of 0-10 cm was found in secondary forest (61.52%) and in the depth of 10-20 cm was found in grasslands (59.15%). The three land uses had higher micro pore compared to the micro pore them selves. The different properties of soil had different effects on soil penetration resistance. Grassland showed the highest value of soil penetrability because of its high level of soil bulk density and clay. Secondary forest had the lowest soil penetrability value due to its high soil organic matter, low soil density, low micro pore space, and very stable soil aggregates. The relationship of soil penetration resistance with water content in three land uses was presented in power regression models with different determination coefficient. In the depth of 0-10 cm, the relationship had R2 of 0.53 in secondary forest, 0.35 in mixed farms, and 0.19 in grasslands. In the depth of 10-20 cm, the relationship of soil penetrability with moisture content had R2 of 0.29 in secondary forest, 0.26 in garden mix, and 0.11 in grasslands. In the days of no rain, the resistence of soil penetration had increased sharply since the third day in secondary forests, since the fifth day in mixed farms, and since the fourth day in grasslands in 0-20 cm deep. The resistence of soil penetration at each land use after 12 days of no rain increased because the soil was drier and harder, however, it did not inhibit the growth of plant roots.
Keyword: physical properties of soil, land use, penetration resistance, water content, Bogor Agricultural University (IPB)

Judul: Karakteristik Anatomi Skelet Kepala Buaya senyulong (Tomistoma schlegelii).
Abstrak: Buaya sepit atau senyulong (Tomistoma schlegelii) merupakan jenis buaya asli Indonesia yang berhabitat di sungai-sungai Sumatera, Kalimantan, dan juga pedalaman Sulawesi. Salah satu ciri khas buaya senyulong adalah bentuk moncong yang runcing dan sempit, namun hingga saat ini informasi mengenai struktur skelet kepala buaya senyulong sangat terbatas. Penelitian ini bertujuan untuk mempelajari karakteristik anatomi skelet kepala buaya senyulong yang dikatikan dengan fungsi dan perilakunya. Penelitian dilakukan secara eksploratif dengan melakukan pengamatan, pencatatan, dan pengambilan gambar dari skelet kepala buaya senyulong. Skelet kepala berukuran panjang 70 cm, lebar 29 cm, dan tingggi 17 cm dengan permukaan kasar pada os nasale, os frontale, os maxilla, os mandibula, os lacrimale, os jugale. Jumlah gigi pada buaya ini sebanyak 78 buah, terdiri dari 4 buah gigi premaxila, 16 buah gigi maxila, dan 19 buah gigi mandibula. Pada regio orbitalis ditemukan dua pasang fenestrae temporales yang berkembang baik. Fenestra supratemporale merupakan lubang oval yang membentang di sepanjang os parietale. Fenestra infratemporale berbentuk segitiga dan dibatasi oleh os squamosum, os postorbitale, os jugulare, dan os quadratum. Os mandibula hewan ini mempunyai symphysis mandibularis yang panjang yaitu garis yang melintang di corpus mandibulae. Secara fungsional ukuran symphysis mandibularis berkaitan dengan adaptasi hewan terhadap diet makan.
Keyword: kepala, moncong, Tomistoma schlegelii