Judul: Studi Populasi dan Distribusi Palahlar (Dipterocarpus hasseltii Blume) di Resort Gunung Salak I, Taman Nasional Gunung Halimun Salak
Abstrak: Taman Nasional Gunung Halimun Salak (TNGHS) merupakan kawasan konservasi yang berpotensi sebagai habitat dari berbagai jenis flora maupun fauna langka dan dilindungi. Palahlar (Dipterocarpus hasseltii Blume) menjadi salah satu jenis tumbuhan langka yang terdapat di kawasan TNGHS dengan status konservasi genting (endangered) dengan tren populasi yang menurun. Penelitian ini bertujuan menganalisis kondisi habitat, kondisi populasi, serta pola sebaran D. hasseltii di Resort Gunung Salak I, TNGHS. Pengambilan data dilakukan secara purposive sampling berdasarkan keberadaan jenis D. hasseltii. Analisis vegetasi menggunakan metode jalur berpetak sebanyak 5 jalur berukuran masing-masing 100 m × 20 m, sehingga total luas petak pengamatan seluas 1 ha. Kondisi umum lokasi didominasi oleh puspa (Schima wallichii) yang memiliki Indeks Nilai Penting (INP) tertinggi pada tingkat pertumbuhan semai, pancang, dan pohon masing-masing sebesar 26,80%, 24,04%, dan 53,86%. Laju regenerasi D. hasseltii berdasarkan tingkat pertumbuhannya menunjukkan kondisi yang tidak normal, karena jumlah semai lebih sedikit dibanding jumlah pancang. Sebanyak 28 individu D. hasseltii ditemukan di lokasi penelitian yang terdiri atas 4 individu semai, 15 individu pancang, 3 individu tiang, dan 6 individu pohon. Hasil penelitian menunjukkan pola sebaran D. hasseltii adalah mengelompok., Gunung Halimun Salak National Park (GHSNP) is a conservation area that potentially becomes a habitat for rare and protected flora and fauna. Palahlar (Dipterocarpus hasseltii Blume) is a rare plant species found in the GHSNP area with an endangered conservation status and declining population trend. This study aimed to analyze habitat conditions, population conditions, and distribution patterns of D. hasseltii at Gunung Salak I Resort of GHSNP. Data were collected by purposive sampling method based on the presence of D. hasseltii. Vegetation analysis used the grid-lined method of 5 lanes measuring 100 × 20 m, each so that the total area of the observation plots was 1 ha. The observation plots were dominated by puspa (Schima wallichii), which had the highest Importance Value Index (IVI) at the growth rate of seedlings (26,80%), saplings (24,04%), and trees (53,86%). The regeneration rate of D. hasseltii, based on its growth rate, showed an abnormal condition, because the number of seedlings was less than the number of saplings. A total of 28 individuals of D. hasseltii were found at the observation plots consisted of 4 individual seedlings, 15 individual saplings, 3 individual poles, and 6 individual trees. The results showed that the distribution pattern of D. hasseltii was clustered.
Keyword: conservation area, Dipterocarpaceae, distribution, endangered species

Judul: Distribution of Puspa (Schima wallichii (DC.) Korth.) in Kawah Ratu Resort, Gunung Halimun Salak National Park, West Java
Abstrak: Puspa (Schima wallichii) merupakan jenis tumbuhan yang mendominasi di kawasan Taman Nasional Gunung Halimun Salak terutama di Resort Kawah Ratu. Jenis puspa termasuk salah satu jenis tumbuhan dataran tinggi yang dapat tumbuh di lahan kritis. Tujuan penelitian ini adalah untuk mengidentifikasi pola penyebaran dan potensi permudaan jenis puspa (S. wallichii) di Resort Kawah Ratu, Taman Nasional Gunung Halimun Salak, Jawa Barat. Pengambilan data dilakukan dengan analisis vegetasi dengan metode petak tunggal seluas 1 ha pada setiap lokasi. Penelitian dilakukan di Blok Pamengpeuk dan Blok Leles. Jenis yang ditemukan pada kedua lokasi penelitian sebanyak 98 jenis. Hasil penelitian menunjukkan pola penyebaran puspa (S. wallichii) adalah mengelompok, baik di Blok Pamengpeuk maupun di Blok Leles. Penyebaran mengelompok menandakan adanya pertumbuhan permudaan yang baik. Kemampuan regenerasi puspa di kedua lokasi tergolong baik karena jumlah individu permudaan puspa lebih banyak daripada individu pohonnya., Puspa (Schima wallichii) is a type of plant that dominates the area of Gunung Halimun Salak National Park, especially at Kawah Ratu Resort. Puspa type is one of the upland plant species that can grow in critical land. The objective of this study is to identify the distribution pattern and the potential for regeneration of puspa species (Schima wallichii) at Kawah Ratu Resort, Gunung Halimun Salak National Park, West Java. Data were collected by analyzing vegetation with a single plot method covering an area of 1 hectare at each location. The research was conducted in the Pamengpeuk Block and the Leles Block. The species found in the two research locations were 98 species. The results showed that the distribution pattern of puspa was clustered, both in the Pamengpeuk block and in the Leles block. A clustered spread indicates good youth growth. The ability of puspa regeneration in both locations was quite good because the number of puspa regeneration individuals was more than the individual trees.
Keyword: distribution, Gunung Halimun Salak National Park, Kawah Ratu Resort, puspa, Schima wallichii, distribution, Gunung Halimun Salak National Park, Kawah Ratu Resort, puspa, Schima wallichii

Judul: Sintesis Nanokristal Magnetit Menggunakan Urea sebagai Penjerap Cr(VI)
Abstrak: The study was to synthesize and characterize magnetite nanocrystal. Magnetite powder was synthesized using hydrothermal method from FeSO4 as precursor and sodium hydroxide and urea as the base sources. Characterization of the obtained powder was carried out using X-ray diffraction, scanning electron microscope, and energy dispersive X-ray analyzer. The crystallite size of magnetite by X-ray diffraction was obtained from 18,23 to 67,34 nm. The scanning electron microscope observations showed that magnetite particles underwent agglomeration. Magnetite powder was used as Cr(VI) adsorbent. The results showed that adsorption capacity for urea-based magnetite at pH 1-5 in 2 hours were 1.92; 1.91; 1.59; 1.20; and 1.21 mg/g, respectively. Adsorption capacity for sodium hydroxide-based magnetite (pH 1-5, 2 hours) were 1.74; 1.83; 0.64; 0.69; and 0.77 mg/g. The results indicated that urea-based magnetite is able to increase adsorption capacity.
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