Judul: Type and degree of residual stand damage cause tree felling in dry lowland forest
Abstrak: Kerusakan ekosistem hutan pada kegiatan pemanenan tidak dapat dihindarkan. Tegakan tinggal merupakan bagian dalam ekosistem hutan yang akan menjadi tegakan inti sebagai kayu yang akan diproduksi pada siklus tebang selanjutnya sehingga, tegakan tinggal dapat menjadi indikator bagi kerusakan ekosistem hutan. Penelitian ini bertujuan untuk mengidentifikasi tipe-tipe kerusakan tegakan tinggal serta tingkat keparahannya dan menghitung tingkat kerusakan tegakan tinggal akibat penebangan pohon. Hasil penelitian menunjukkan bahwa tipe kerusakan yang paling banyak rusak adalah tipe roboh/condong sebesar 35.79% dan tipe pecah/patah batang sebesar 28.14%. Berdasarkan tingkat keparahan, sebagian besar dari kerusakan tegakan tinggal memiliki tingkat keparahan berat yaitu, sebesar 63.39%. Tingkat kerusakan tegakan tinggal berdasarkan populasi pohon akibat penebangan sebesar 8.54% (37 pohon/ha) dengan intensitas penebangan 7 pohon/ha tergolong tingkat kerusakan ringan., Damage of forest ecosystem in timber harvesting can not be avoidable. Residual stand is a part of forest ecosystem that will be prime stand as timber product for the next harvesting cycles so, residual stand can used as indicator of forest ecosystem damage. The research aims to identify types of residual stand damage with the big of injury and calculate the degree of residual stand damage cause tree felling. The research showed that type of residual stand damage which many occur are collaps/leaning is 35.79% and broken trunk is 28.14%. Based on the big injury, most of residual stand damage have serious injury that is 63.39%. The degree of residual stand damage based on tree population is 8.54% (37 tree/ha) with felling intensity is 7 tree/ha belong to low damage degree.
Keyword: penebangan, tingkat kerusakan tegakan tinggal, tipe kerusakan tegakan tinggal

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: 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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