Judul: Infiltration Capacity and Aggregate Stability on Land with Slot Tillage System Equipped Bund Terrace Variants and their Relationship with Surface Runoff and Erosion
Abstrak: Proses terjadinya erosi sangat berkaitan dengan aliran permukaan. Aliran permukaan mengakibatkan partikel-partikel tanah di bagian permukaan terlepas dan terangkut ke tempat lain. Besarnya aliran permukaan dan erosi dipengaruhi oleh banyak faktor, diantaranya adalah stabilitas agregat tanah dan kapasitas infiltrasi tanah. Oleh karena itu, pengendalian aliran permukaan dan erosi dapat diarahkan pada perbaikan stabilitas agregat dan kapasitas infiltrasi tanah, antara lain dengan pengolahan tanah secara slot till dan berbagai varian teras gulud. Penelitian yang bertujuan mengetahui pengaruh sistem olah tanah slot till dengan berbagai varian teras gulud terhadap kapasitas infiltrasi dan stabilitas agregat tanah serta hubungannya dengan aliran permukaan dan erosi dilakukan di Kebun Pendidikan Cikabayan IPB. Penelitian menggunakan Rancangan Acak Lengkap (RAL) terdiri dari lima perlakuan, masing-masing dengan tiga kali ulangan, yaitu P1) kontrol, P2) slot till, P3) slot till dengan teras gulud, P4) slot till dengan teras gulud diberi mulsa organik pada saluran terasnya, P5) slot till dengan teras gulud diberi mulsa organik dan dibuat Lubang Resapan Biopori (LRB) pada saluran terasnya. Pengukuran infiltrasi dilakukan menggunakan double ring infiltrometer dan stabilitas agregat diukur menggunakan ayakan kering dan basah. Hasil pengamatan menunjukkan bahwa perlakuan slot till dengan berbagai varian teras gulud dapat meningkatkan kapasitas infiltrasi dan stabilitas agregat serta menurunkan aliran permukaan dan erosi. Perlakuan slot till dengan teras gulud serta mulsa organik pada saluran dan LRB (P5) memberikan pengaruh yang lebih signifikan terhadap kapasitas infiltrasi dan stabilitas agregat tanah dibandingkan dengan perlakuan lainnya. Nilai kapasitas infiltrasi dan stabilitas agregat pada bidang olah berkorelasi nyata terhadap aliran permukaan dan erosi., The process of erosion is closely related to surface runoff. Surface runoff causes soil particles on the surface to be detached and transported to other locations. The amount of surface runoff and erosion is influenced by many factors, including soil aggregate stability and soil infiltration capacity. Controlling surface run off and erosion may therefore, be directed to improving the two soil characteristics which can be done by practicing slot tillage in combination with various bund terraces. Research aimed at determining the effect of a slot tillage system combined with various bund terrace on infiltration capacity and soil aggregate stability and their relationship to surface runoff and erosion was conducted at IPB's Cikabayan Education Farm. The research used a completely randomized design consisting of five treatments with three replications, namely P1) control, P2) slot till, P3) slot till with bund terrace, P4) slot till with bund terrace with organic mulch applied on the trench, P5) slot till with bund terrace with organic mulch and biopore infiltration pits on the trench. Infiltration was measured using a double ring infiltrometer and aggregate stability was measured using dry and wet sieves. The results showed that slot till treatment with different variants of bund terrace can increase infiltration capacity and aggregate stability and reduce surface runoff and erosion. The slot till treatment with bund terrace with organic mulch application and biopore infiltration pits on the trench (P5) gave a more significant effect on soil aggregate stability and soil infiltration capacity compared to other treatments. The value of infiltration capacity and aggregate stability in cultivated field was significantly
Keyword: lubang resapan biopori, mulsa organik, sifat fisik tanah, sistem olah tanah, saluran

Judul: The Relationship between Soil Hydraulic Conductivity and Soil Physical Properties as a Consequence of Soil Conservation Tillage and Its Relationship to Surface Runoff and Erosion
Abstrak: Aliran permukaan dan erosi merupakan penyebab penurunan kualitas sifat fisik tanah di daerah tropika basah seperti di Indonesia. Untuk mengurangi besarnya aliran permukaan dapat dilakukan dengan peningkatan kemampuan peresapan tanah (hantaran hidrolik). Berbagai teknik konservasi tanah dan air dapat meningkatkan hantaran hidrolik tanah melalui perbaikan sifat-sifat fisik tanah, yang selanjutnya diharpkan dapat mengurangi aliran permukaan dan erosi. Oleh karena itu perlu dilakukan penelitian tentang pengaruh teknik konservasi tanah dan air terhadap hantaran hidrolik tanah. Serangkaian penelitian dilakukan di lapangan untuk mengamati hantaran hidrolik dan sifat-sifat fisik yang mempengaruhinya serta pengaruhnya terhadap aliran permukaan dan erosi. Penelitian dilakukan di Kebun Pendidikan Cikabayan, IPB Dramaga, dengan perlakuan Kontrol (P1), Slot Till (P2), Slot Till + teras gulud + saluran (P3), Slot Till + teras gulud + saluran + mulsa organik (P4), dan Slot Till + teras gulud + saluran + mulsa organik + LRB (P5) yang disusun dalam rancangan acak lengkap (RAL). ). Hasil penelitian menunjukkan bahwa hantaran hidrolik pada perlakuan Slot Till + teras gulud + saluran + mulsa organik (P4) paling besar (3.05 cm/jam), diikuti oleh hantaran hidrolik pada perlakuan Slot Till + teras gulud + saluran + mulsa organik + LRB (P5; 2.68 cm/jam), P3 (2.32 cm/jam), P2 (1.71 cm/jam), dan P1 (0.85 cm/jam). Hantaran hidrolik tanah dipengaruhi oleh bobot isi, stabilitas agregat, dan ruang pori drainase. Peningkatan hantaran hidrolik tanah akibat teknik konservasi tanah dan air di atas dapat menurunkan aliran permukaan dan erosi., Surface runoff and erosion are causes of a decrease in the quality of soil physical properties in wet tropical areas such as Indonesia. To reduce the amount of surface runoff, it can be done by increasing the soil's hydraulic conductivity. Various soil and water conservation techniques can increase the hydraulic conductivity of the soil by improving the physical properties of the soil, which in turn is expected to reduce surface runoff and erosion. Therefore, it is necessary to conduct research on the effect of soil and water conservation techniques on soil hydraulic conductivity. A series of studies were carried out to observe hydraulic conductivity and the physical properties that influence it as well as their effect on surface runoff and erosion. The research was conducted at the Cikabayan Field Stasion, IPB Dramaga, with Control (P1), Slot Till (P2), Slot Till + bund terrace + channel (P3), Slot Till + bund terrace + channel + organic mulch (P4), and Slot treatments. Slot Till + bund terrace + channel + organic mulch + LRB (P5) arranged in a completely randomized design (RAL). The results showed that the hydraulic conductivity in the Slot Till + bund terrace + channel + organic mulch (P4) treatment was the greatest (3.05 cm/hour), followed by the hydraulic conductivity in the Slot Till + bund terrace + channel + organic mulch + LRB (P5; 2.68 cm/hour), P3 (2.32 cm/hour), P2 (1.71 cm/hour), and P1 (0.85 cm/hour). Soil hydraulic conductivity is influenced soil bulk density, soil aggregate stability, and drainage pore space. The increased of soil hydraulic conductivity due to soil and water conservation techniques can reduce surface runoff and erosion
Keyword: Erosion, Runoff, Soil and Water Conservation, Soil hydraulic conductivity, Soil physical properties

Judul: Mitochondrial DNA Gene Organization and Phylogenetic Relationship of Naja siamensis
Abstrak: Naja siamensis is one of Asiatic cobra in the Family of Elapidae, known as a cryptic snake. It has many morphological variations that lead to misidentification. Misidentification can cause the wrong concept in developing antivenom types due to high snakebite cases occur in Thailand. Thus, an accurate species identification using a molecular approach is crucially required. Mitochondrial DNA has been used widely in snake molecular studies. These studies were aimed to determine the arrangement of the N. siamensis partial mitochondrial genes using reptile-oriented primers and to reveal the phylogenetic relationship among other species of Asian cobra. DNA extraction was carried out based on the standard DNA salting-out protocol and was conducted by bioinformatics analysis using BLASTn and MEGA 6 software. Gene annotation was performed against N. kaouthia complete genome. A total of 3121 bp of N. siamensis mtDNA genes were sequenced consisting of partial of six regions: 16S rRNA, ND1, tRNA-Ile, CRII region, tRNA-Leu, tRNA-Gln, and COI genes. The mtDNA gene organization of N. siamensis was predicted to has a similar pattern with the common Elapidae mtDNA gene organization. This study showed that there is a monophyletic form in Naja genus and N. kaouthia is the closest species with N. siamensis based on partial 16S rRNA and ND1 gene.
Keyword: 16S rRNA, Elapidae, ND1, phylogenetic relationship