Judul: Keterbukaan Areal Hutan Akibat Kegiatan Pemanenan Kayu di Pulau Siberut, Kepulauan Mentawai, Sumatera Barat
Abstrak: Timber harvesting was an important activity in the forest management, changes of the tree and biomass into a form that can be moved into another place easily so that it can be useful for live and livelihood especially for economics and cultures. That forest opened up area was caused by the trees felling activity, also by skidding road and landing site. The objective of the research was analyze the percentage of forest opened up area by the felling and skidding activities from stump site to the landing site. The data that was used which collected from the year of 2012 and 2013 work plan and also timber harvesting road map. The calculation of forest opened up area was performed from cutting point to the landing site. The plot used in this research is 12 plots with 1 Ha in each plot, the plot ware placed in trees felling to used by low, medium and high felling intensity and landing site area, and also in the skidding road. The forest opened up area calculated by measuring the area that has been opened from the trees felling step until it transported to landing site. This research showed that the forest opened up area caused by forest harvesting activity was about 32.33% with the highest percentage was from trees felling activity was 18.33%, skidding road making was 8.70%, wood skidding activity was 4.60%, and landing site was 0.70%. The timber harvesting technique that applies in that forestry company is a conventional technique.
Keyword: harvesting techniques timber, forest opened up area, felling intensity

Judul: Kehilangan Cadangan Karbon pada Pemanenan Secara Mekanis (Studi Kasus Konsesi Hutan PT. Salaki Summa Sejahtera, Pulau Siberut Provinsi Sumatera Barat)
Abstrak: PT. Salaki Summa Sejahtera has 48.420 ha concession area on the island of Siberut. Management forest of silvicultural systems applied using Selective Cutting and Planting Indonesia (TPTI). Siberut island was set by UNESCO as a biosphere reserves in 1981 so that the impact of forest harvesting must be minimized to preserve the forest. Reduce Impact Logging is a technique that used to reduce impact of forest harvesting. This research aims to analyze an amount of forest openess and loss of carbon stocks and the relationship with harvesting volume . The research was conducted on RKT 2011 block of IUPHHK PT. Salaki Summa Sejahtera with an area of 962 ha. We conducted a 100% inventory of roads and log decks in RKT 2011 block. Forest stand density of ≥ 20 cm diameter average 76,11 trees/ha with an average volume 176,11 m3/ha. Carbon biomass of mature trees are 67,79 % total carbon biomass. Harvesting intensity of 5,80 trees/ha (47,89 m3/ha) is lower than annual allowable Cut (66,41 m3). Forest openness average of 6,45 % from main roads (0,64%), branch roads (2,12%), skid trails (3,24%), Landings (0,42%), and camp (0,03%). Forest openess is not correlated with harvesting volume (R2 = 0,38 %). Harvesting a tree needs 0,54 ha of roads and caused opened area 13,31 m2. Loss of carbon stocks are influenced by the amount of harvesting intensity (R2 = 0,98). Loss of carbon stocks that occured are 41,00 ton C/ha due to forest openness (5,05 ton C/ha), logging (30,62 ton C/ha), dan residual stand damage (5,33 ton C/ha). Crushed trees are categorized as a dead wood and reduced carbon stocks in a forest. Harvesting a tree caused loss of 0,86 ton C/ha carbon stocks
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Judul: Tinjauan immunoglobulin dan peranannya dalam saluran gastrointestinal terutama terhadap serangan cacing
Abstrak: Immunoglobulin merupakan suatu glikoprotein yang terdapat dalam serum dan cairan jaringan. Immunoglobulin ini diproduksi bila sistem limfoid berkontak dengan anti gen. Immunoglobulin ini berperan dalam melindungi tubuh dari infeksi. Didalam tubuh immunoglobulin terdiri dari lima klas yang masing-masing klas mempunyai karakteris- tik dan fungsi yang spesifik yaitu Ig G, Ig A, Ig M, Ig E dan Ig D.. Diantara klas immunoglobulin, Ig G adalah yang pa- ling melimpah dalam serum darah dan strukturnya dapat di pakai sebagai model bagi immunoglobulin yang lain. Dalam saluran gastrointestinal, immunoglobulin da- pat berperan dalam sistem kekebalan lokal. Diantara ke- lima klas immunoglobulin, Ig A merupakan immunoglobulin terbesar yang terdapat dalam sekresi saluran gastrointes tinal. Hal ini disebabkan karena Ig A mampu bertahan terhadap enzim proteolitik yang terdapat dalam saluran gastrointestinal dibanding klas immunoglobulin lainnya. Agar dapat bertahan terhadap enzim tersebut Ig A dilin- dungi oleh komponen sekretori. Oleh karena itu struktur Ig A yang berada dalam serum berbeda dengan Ig A yang terdapat dalam sekresi saluran gastrointestinal. Ig A sekresi ini mempunyai kemampuan mencegah perlekatan bakteri pada permukaan mukosa saluran gastrointestinal dan dapat mengontrol koloni mikroorganisma yang secara normal terdapat dalam saluran gastrointestinal seperti Escherichia coli agar tidak membahayakan tubuh. Dalam resistensi terhadap virus, Ig A dapat mencegah replikasi virus pada mukosa yang merupakan tempat masuknya. Ig A memiliki dua subklas yang dapat dibedakan oleh asam amino pada rantai alpha () dan pada pengikat disulfida…dst
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