Judul: Pengaruh pemberian soil conditioner terhadap sifat fisik tanah latosol Darmaga
Abstrak: Tanah Latosol mempunyai potensi yang tinggi bagi pengembangan lahan pertanian dan merupakan tanah dominan kedua setelah Podsolik. Akan tetapi tanah Berte tersebut memiliki kemasaman tanah tinggi, miskin kandungan hara makro terutama P, K, Ca, dan Mg, dan kandungan bahan organik rendah. Untuk mengatasi permasalahan tersebut perlu dilakukan penambahan bahan organik sebagai soil conditioner. Bahan pembenah tanah (soil conditioner) didefinisikan sebagai bahan-bahan sintetis atau alami, organik atau mineral, berbentuk padat maupun cair yang mampu memperbaiki sifat fisik, kimia, dan biologi tanah. Penelitian bertujuan mempelajari pengaruh penambahan soil conditioner terhadap perbaikan sifat fisika tanah Latosol Darmaga. Perlakuan yang diterapkan adalah dosis soil conditioner yaitu A (perbandingan soil conditioner: tanah, 1:20), B (soil conditioner: tanah, 1: 30), dan C (soil conditioner tanah, 1:40), O (tanpa perlakuan). Soil conditioner yang @digunakan dalam bentuk briket dicampur merata dengan tanah dengan jumlah total soil conditioner dan tanah sebesar 4 kg (BKM). Soil conditioner dengan tanah diinkubasi dalam kondisi sekitar kapasitas lapang selama 2 bulan. Bogor) Soil conditioner memberi pengaruh cukup baik dalam meningkatkan pori drainase cepat. Sedangkan bobot isi, porositas tanah, kadar air tanah, pori drainase sangat cepat, dan pori drainase lambat serta pori air tersedia tidak dipengaruhi oleh aplikasi soil conditioner. Walaupun demikian terdapat kecenderungan menurunkan bobot isi tanah (antara kontrol dengan dosis optimum yaitu dosis A mengalami penurunan bobot isi sebesar 6%), pori drainase sangat cepat (19%), meningkatkan kadar air jenuh (9%), porositas tanah (1,5%), pori drainase lambat (66%), dan meningkatkan pori air tersedia Latosol Darmaga (73%). Hal ini disebabkan inkubasi soil conditioner baru dilakukan dalam waktu 2 bulan, sedangkan untuk memperbaiki Usifat fisik tanah diperlukan waktu yang lebih lama…dst
Keyword: Soil bulk density, Soil conditioner, Soil porosity, Quick drainase pore

Judul: Populasi Mikrob Tanah Latosol Darmaga yang diinkubasi Soil Conditioner Berbahan Kompos Jerami Padi
Abstrak: Latosol that is found widespread in Indonesia, has characteristics such as it contains much aluminium and Iron oxides, deficient in plant nutrients due to excessive leaching, reddish in color, horizons in the soil profile are not distinct and deep solumn (over 150 cm). Soil conditioner has an important role in improving soil phyical properties such as stimulating granulation, soil aeration and water holding capacity. Soil conditioner from rice straw compost could also enhance beneficial microbial population and their activity, such as nitrogen fixers, phosphate solubilzers and cellullose decomposers. Organic matter accumulation, nutrient cycles and the formation of stable soil structure are strongly influenced by soil organism activities. Thus, the use of soil conditioner on Latosols is expected to improved the physical, chemical and biological properties of soils. This research aims 1) to evaluate the microbial (bacteria and fungi) population in soils incubated by soil conditioner made from rice straw compost, 2) to study the relationship between microbial population and some soil physical properties (aggregate stability and soil moisture). The experiment was arranged using completely randomized designed with two factors i.e. 1) the treatment of soil conditioners (with and without soil conditioner) and 2) incubation time (2 and 6 months). The treatment was replicated three times, thus resulted in 12 experimental units. The result showed that soil conditioner significantly increased soil moisture content, compared to the control. After six months incubation, soil conditioner had no effect yet on the soil aggregate stability and soil microbial population, compared to the control
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Judul: Posisi Filogenetik Kura-Kura Carettochelys Insculpta  (Reptillia: Testudinata)
Abstrak: Carettochelys insculpta is an endemic freshwater turtle of southern Papua and northern Australia. Phylogenetic position of this turtle is remain unresolved until now. Most of the research conducted show close relationships of C. insculpta and members of Trionychidae family. However, some of the research show distance between C. insculpta and members of Trionychidae family. This research is conducted to analyze phylogenetic relationship between C. insculpta and other members of Testudinata using 12S rRNA, 16S rRNA, and both gene as markers. DNA samples were obtained from three different organisms of C. insculpta. Two species used as outgroups were Alligator mississippiensis and Iguana iguana. Phylogenetic analysis was carried out using Neighbor-Joining method with Felsenstein 1981 (F81) modeltest. A polytomy tree of Testudinata was produced by using 12S rRNA gene. However, analysis using 16S rRNA and both genes as markers confirmed that C. insculpta was located between the Chelonidae and the Trionychidae family.
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