Judul: Laju Infiltrasi Air pada Jalur Sarad Skidder dan Bulldozer di IUPHHK-HT PT Wirakarya Sakti Provinsi Jambi
Abstrak: Wood harvesting activities using heavy equipment has been a trend especially for skidding activities because it gives benefits such as effectively and efficiently in wood harvesting. Beside the benefits, heavy equipment usage in forest harvesting especially for skidding also has negative impacts on the environment such as infiltration rate that will cause soil damage in the case of soil compactness. The purpose of this research is to know the rate of water infiltration (cm/hours) on each trip (rit) resulting from wood skidding activity using skidder and bulldozer and also to knowing ground pressure caused by these heavy equipment. The biggest water capacity decrement is happens between rit 3 and rit 4 with using skidder with rate 19.07 cm/hour. The biggest decrement using bulldozer is happens between rit 8 and rit 9 with rate 9.57 cm/hour. On this case can be conclude because of in that points are the beginning of the soil physical disturbance that cause the disturbance to water infiltration process and that things can be prove by calculating the ground pressure by each skidding equipment. Ground pressure received the ground produced by the rubber tire on skidder amounted 20.30 tons/m2 in conditions without charge and 132.24/m2 when charged. Ground pressure received the ground produced by the crawler tire on bulldozer amounted 7.67 tons/m2 in conditions without charge and 50.68 tons/m2 when charged.
Keyword: log skidding, soil compaction, Infiltration rate

Judul: Produktivitas dan Biaya Kegiatan Penyaradan Menggunakan Skidder dan Bulldozer pada Hutan Tanaman Industri di PT. Wirakarya Sakti, Jambi
Abstrak: Timber harvesting is a series of timber removal activity from forest to the places where the wood is used or processed. The success indicators of timber harvesting are optimal production at an economical cost and lowest environmental damage. The objectives of this study are to calculate and compare the productivity and cost of skidding use skidder and bulldozer. The study showed that an average productivity using skidder is 42.51 m3/hr, greater than bulldozer that is equal of skidding to 35.50 m3/hr. Base on this study, operating costs and skidding cost, are Rp 476 644/hr and Rp 11 213/m3 respectively for skidder, and are Rp 526 932/hr and Rp 14 834/m3 for bulldozer. Skidding productivity using skidder is more economical better than bulldozer.
Keyword: cost., productivity, skidding, timber harvesting

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