Judul: Residual stand damage and the openness of area causedby timber harvesting in dry low land natural forest
Abstrak: Dalam tahapan-tahapan pemanenan hutan, kegiatan yang paling banyak menimbulkan dampak negatif pada lingkungan adalah kegiatan penyaradan. Bentuk kerusakan akibat penyaradan, yaitu: kerusakan tegakan tinggal dan keterbukaan areal. Penelitian ini bertujuan untuk mendapatkan informasi mengenai tingkat kerusakan akibat kegiatan penyaradan dan mengetahui luas areal yang terbuka akibat penyaradan. Metode pengukuran berupa pengukuran pada tingkat tiang dan pohon sebelum dan setelah penyaradan di 10 plot contoh penelitian seluas 1 ha. Persentase kerusakan populasi akibat penyaradan sebesar 17.28% atau sebesar 75 pohon/ha. Hasil penelitian pada kategori tingkat keparahan pada rusak ringan sebesar 6%, rusak sedang sebesar 3.7% dan rusak ringan berat sebesar 90.3%. Keterbukaan areal yang terjadi akibat penyaradan sebesar 12.55% dengan luas rata-rata sebesar 1255.41 m² atau 0.12 ha/plot dengan panjang rata-rata 235 m/ha. Sedangkan panjang rata-rata keterbukaan areal akibat penyaradan per-hm sebesar 2.35 hm/ha dengan rata-rata kerusakan pohon sebesar 32 pohon/hm., With in the stages of forest harvesting, the activity with the most negative impact on the environment is skidding. The types of damage skidding are residual stand damage and the openness of the area. This research is aimed to get information of the damage level of skidding activities in dry low land natural forest and to know the openness area caused by skidding. The method in this research was to measure the damage of the stand of pole and tree level before and after skidding in 10 sample plots which 1 hectare in each plot, percentage of damaged population caused by skidding was 17.28% or 75 trees/ha. The results of this study shows the percentage of minor damage of 6%, moderate damage of 3.7%, and severe damage of 90.3%. The openness of the area damaged by skidding was 12.55% within average basal area was 1255.41 m2 or 0.12 ha/plot and the average length was 235 m/ha. Whereas, the average length of the openness of the area caused by skidding was 2.35 hm-hectare within average stands damage was 32 trees/hm.
Keyword: kerusakan tegakan tinggal, keterbukaan areal, tingkat kerusakan

Judul: Kerusakan Tegakan Tinggal Akibat Penebangan dan Penyaradan Kayu di Areal IUPHHK-HA PT. Sarmiento Parakantja Timber, Kalimantan Tengah
Abstrak: Tree felling and skidding a part of forest harvesting activities that would cause damage to the residual stand. This study aims to calculate and identify the extent of damage to remaining trees with the diameter of 10 cm up due to tree felling and skidding. The result of this research showed that the residual stand damage caused by felling and skidding in PT. Sarmiento Parakantja Timber is included medium damage, namely 28.41%. Based on the size wound on damaged trees, the trees damaged consist of severely damaged 49.30%, medium damaged 20.88% and lightly damaged 29.82%. The average size of the open area caused by felling and skidding is at 232.48 m2/tree or 3804.62 m2 ha-1. High logging intensity would cause higher damage to the residual stand and higher opened area as well.
Keyword: skidding, tree felling, residual stand damage

Judul: Hydrothermal Synthesis of Biphasic Calcium Posphate
Abstrak: Biphasio calsium phosphate (BCP), which was a mixture of hydroxypatite (HA) and tricalcium phosphate (TCP), was synthesized by hydrothermal method followed by sintering process. Hydroxyapatite was produced by using natural calcium source CaO from hen's eggshell and (NH4)2HPO4 as phosphate souce, other hydroxyapatite sample was produce by using synthetic calcium source Ca(OH) and H3PO4 as phosphate source.
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