Judul: Modeling the Dynamics of Aboveground Carbon  Stocks in Peat Swamp Forest in Riau Province
Abstrak: Pemanasan global merupakan ancaman nyata bagi pembangunan berkelanjutan. Ekosistem Gambut merupakan salah satu ekosistem yang paling rentan dan sebagai sumber emisi yang besar apabila tidak dikelola dengan baik. Dalam mengantisipasi perubahan iklim, perlu dilakukan penghitungan kandungan biomassa dan stok karbon hutan rawa gambut secara akurat. Penelitian ini bertujuan untuk membangun model dengan menyusun beberapa skenario sehingga memberikan rekomendasi terbaik dalam pengelolaan hutan rawa gambut bekas tebangan di PT. Diamond Raya Timber, Kabupaten Rokan Hilir, Riau. Metode yang digunakan adalah metode deskriptif berdasarkan pendekatan system dinamik. Model simulasi menggunakan software Stella 9.0.2 dengan memasukkan persamaan ingrowth, upgrowth, dan mortality tegakan hutan dengan kelas diameter 10– 19.9 cm, 20–29.9 cm, 30–39.9 cm, 40–49.9 cm, 50–59.9 cm, dan 60 cm up. Hasil penelitian menunjukkan bahwa struktur tegakan hutan bekas tebangan mengalami penurunan jumlah pohon dan stok karbon setiap tahunnya akibat tingginya angka kematian pada setiap kelas diameter. Hasil simulasi menunjukkan bahwa siklus 40 tahun dengan intensitas tebang 25% pada rotasi ketiga jumlah stok karbon meningkat sebesar 73.91 ton/ha dan menghasilkan stok karbon yang lebih besar dibandingkan siklus lainnya. Intensitas tebang berkorelasi negatif dengan stok karbon karena semakin tinggi intensitas tebang, maka semakin rendah stok karbon tegakan tinggal. Penyimpanan stok karbon tegakan akan meningkat setiap tahun dan menurun lagi ketika penebangan dilakukan., Global warming is a real threat to sustainable development. Peat swamp forest is one of the most vulnerable ecosystem and resported as the biggest source of emissions if not sustainably managed. In anticipating climate change, it is necessary to accurately calculate the biomass and carbon stocks of peat swamp forests. This study aims to build a model by compiling several scenarios to provide the best recommendations for managing logged-over peat swamp forest at PT. Diamond Raya Timber, Rokan Hilir Regency, Riau. The method used a System Dynamics approach. The model and simulation use Stella 9.0.2 incorporating ingrowth, upgrowth, and mortality equations of the forest stands with diameter classes of 10–19.9 cm, 20–29.9 cm, 30–39.9 cm, 40–49.9 cm, 50–59.9 cm, and 60 cm up. The results showed that the stand structure of logged-over peat swamp forests decreased the number of trees and carbon stocks each year due to the high mortality rate in each diameter class. The simulation results show that a 40-year cycle with a cutting intensity of 25% in the third rotation increases the carbon stock by 73.91 tons/ha and produces a larger carbon stock than the other cycles. Cutting intensity negatively correlates with carbon stock because the higher the cutting intensity, the lower the carbon stock of the remaining trees. Standing carbon storage will increase every year and decrease again when logging is carried out.
Keyword: Dinamika Tegakan, stok karbon, siklus dan intensitas tebang, model simulasi, sistem TPTI

Judul: Model of Stand Structure Dynamic and Carbon Potential in Papua Logged-Over Natural Forest of Papua
Abstrak: Hutan alam bekas tebangan memiliki komposisi struktur tegakan yang berbeda dengan hutan alam primer sebagai akibat dari kegiatan penebangan. Kayu umumnya merupakan komoditas utama dari hutan, namun tren pemanfaatan hutan saat ini mengarah pada usaha pemanfaatan hasil hutan bukan kayu dan jasa lingkungan. Kegiatan pengelolaan hutan lestari tidak hanya dilihat dari keberlanjutan produksi kayu tetapi dilihat dari keberlanjutan peran hutan sebagai penyedia jasa lingkungan, salah satunya adalah sebagai penyimpan karbon. Pada penelitian ini akan dikaji bagaimana dinamika struktur tegakan dan karbon hutan serta skenario yang tepat dalam menentukan siklus dan intensitas tebang pada tegakan pemeliharaan dan tanpa pemeliharaan di PT. Tunas Timber Lestari, Papua. Data yang digunakan merupakan data seri PUP (Petak Ukur Permanen) hasil pengamatan selama 10 tahun (2005-2015). Analisa data dilakukan dengan membentuk model dinamika struktur tegakan dan karbon hutan dengan menggunakan variabel laju ingrowth, upgrowth, dan mortality. Berdasarkan hasil analisis menunjukkan bahwa rata-rata laju ingrowth pada tegakan dengan pemeliharaan cenderung lebih kecil dibandingkan dengan tegakan tanpa pemeliharaan. Besarnya nilai upgrowth bervariasi dimana upgrowth mengalami peningkatan pada kelas diameter 10-19 cm sampai 30-39 cm untuk tegakan tanpa pemeliharaan dan 20-29 cm sampai 40-49 cm untuk tegakan dengan pemeliharaan. Tingkat mortality pada tegakan tanpa pemeliharan cenderung lebih tinggi terutama pada kelompok jenis Rimba Campuran dan Non Komersil, sedangkan pada kelompok jenis Meranti tingkat kematian banyak terjadi pada tegakan dengan pemeliharaan. Siklus dan intensitas tebang optimal sebagai salah satu alternatif skenario dalam perencanaan pengelolaan hutan adalah siklus 30 tahun dan intensitas tebang 40% pada kelas diameter 40 dan 50up cm, Logged-over natural forest has a different stand structure composition from primary natural forest as a result of logging activities. Woods are commonly the main commodity of forests, but the current trend of forest use has led to non-timber forest products and environmental services. Sustainable forest management activities are not only seen from the sustainability of wood production but also from the sustainable role of forest as a provider of environmental services, one of which is as a carbon storage. In this study, the dynamics of stand structure and carbon and the appropriate scenario in determining the cutting cycle and intensity of stands with and without treatments at PT. Tunas Timber Lestari, Papua, were examined. The data used were Permanent Sample Plots or ( Petak Ukur Permanen, PUP) data series that were observed for 10 years (2005-2015). Data analysis was carried out by formulating a dynamic model of stand structure and carbon potential using the variables of ingrowth, upgrowth, and mortality rates. Results of the analysis showed that the average ingrowth rate in stands with treatment was smaller than stands without treatment. The value of upgrowth varied where upgrowth increased in diameter classes from 10-19 cm to 30-39 cm for stands without treatment and 20-29 cm to 40-49 cm for stands with treatment. The mortality rate in stands without treatment tended to be higher, especially in species groups of Rimba Campuran and Non-Commercial groups, while in Meranti group, the mortality rate mostly occurred in the stands with treatment. Optimal cutting cycle and intensity as an alternative scenario in forest management planning is cycle
Keyword: Carbon, Ingrowth, Mortality, Stand Structure Dynamic, Upgrowth

Judul: Studi Kasus Liver Neoplasia pada Anjing Shih Tzu
Abstrak: Liver neoplasia is the excessive and uncontrolled replication of hepatocytes that forms nodules visible in ultrasonography. The purpose of this study is to study and discuss the characteristic, diagnosis and treatment of liver neoplasm through the interpretation of ultrasonography and hematology in a Shih Tzu dog. Ultrasonography is conducted with a Chison Q8 ultrasound machine with a 5 to 7 MHz frequency convex probe on lateral recumbency. The blood cells, liver enzymes and nodules sizes were the main parameters in this study. The results in the period of three years from 2021 to 2023 were interpreted and supported with secondary data sources. The Shih Tzu dog is 14 years old in the year 2023 with a body weight of 5.21kg. No obvious clinical signs were observed during previous examinations. However, lethargy, vomiting and anorexia were recorded in its latest examination. Thrombocytosis, granulocytosis, high liver enzymes and hypoglycemia, which are some of the neoplastic clinical manifestations were also presented by this patient. Besides, liver neoplasm, spleen neoplasm and biliary sludge were the sonogram findings of this patient. The liver and spleen neoplasm was observed stable, while the biliary sludge volume fluctuated. The treatment strategy recorded is Ondansetron, Samylin®, Ornipural and Ursodeoxycholic acid.
Keyword: Blood biochemistry profile, Hematology, Liver Neoplasia, Shih Tzu, Ultrasonography