Judul: Survivorship and Growth Rate of Rasamala (Altingia excelsa Noronha), Puspa (Schima wallichii (DC.) Korth.) and Jamuju (Dacrycarpus imbricatus (Blume) de Laub.) on Degraded Land in the Upstream of Cisadane Watershed
Abstrak: Changes in land use often threaten biodiversity. A slow primary succession can, however, be accelerated by conducting a restoration program. The aims of this study were to i) obtain data of survivorship and growth rate and ii) assess the influences of environmental factors on the growth of Rasamala (Altingia excelsa), Puspa (Schima wallichii), and Jamuju (Dacrycarpus imbricatus) on a degraded land in the upstream of Cisadane watershed. Observations were carried out two times: 6 and 12 months after planting. Survivorship percentages at different slopes were obtained by dividing the amount of living species during the period of the observation with the total amount of plants planted at the beginning of the observation. A PCA biplot analysis was used to assess the interaction between biotic and abiotic factors influencing the survivorship. Growth rate was done by measuring the height, diameter, and canopy spread of individual plants. Assessments of biotic and abiotic environment that influence the growth rates were also conducted. The results showed that the survivorship percentages of Rasamala, Puspa, and Jamuju were 87,18%, 82,05%, and 77,14%, respectively. On the 40° slopes, the survivorship of Rasamala was 93,75%, while those of Puspa and Jamuju were 84,61% and 66,67% respectively. On the 60% slopes, the survivorship was 82,25% for Rasamala, 81,81% and 64,70% for Puspa and Jamuju respectively. Higher growth rate was found in Jamuju, followed by Puspa and Rasamala. Environmental factors (both biotic and abiotic) significantly influenced the three species survivorship. Plant height, diameter and canopy area had significant correlations with plant growth rates.
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Judul: Composition and Stand Structure of Puspa (Schima wallichii (DC.) Korth. in Mount Halimun Salak National Park, Sukabumi
Abstrak: Puspa termasuk salah satu jenis tumbuhan dataran tinggi yang mampu tumbuh di lahan kritis, sehingga dapat digunakan untuk memulihkan area hutan pegunungan yang rusak. Penelitian ini bertujuan untuk menganalisis komposisi jenis, struktur tegakan Schima wallichii (DC.) Korth. dan aspek biofisik tegakan Schima wallichii (DC.) Korth. di zona inti TNGHS. Metode penelitian ini menggunakan analisis vegetasi dengan plot yang ditempatkan secara purposive sampling. Hasil penelitian menunjukkan bahwa komposisi jenis memiliki kerapatan tinggi sampai rendah berturut-turut dari semai sampai pohon. Keseluruhan plot pada lokasi penelitian didominasi oleh Schima wallichii (DC.) Korth. Struktur tegakan hutan pada seluruh plot menunjukkan pola hubungan jumlah pohon dengan kelas diameter membentuk kurva membentuk “J” terbalik (eksponen negatif). Sebaran puspa dalam plot penelitian menunjukkan sebaran mengelompok. Hal tersebut berdampak baik untuk proses regenerasi alami. Seluruh aspek biofisik yang diukur pada plot penelitian relatif seragam., Puspa is one of the highland plant species that can grow on critical land, so it can be used to restore damaged mountain forests. This study aims to analyze the species composition, stand structure of Schima wallichii (DC.) Korth. and biophysical aspects of Schima wallichii (DC.) Korth. stands in the core zone of TNGHS. This research method uses vegetation analysis with plots placed by purposive sampling. The results showed that the species composition had high to low density from seedling to tree, respectively. The entire plot at the research site was dominated by Schima wallichii (DC.) Korth. The structure of forest stands in all plots showed a pattern of relationship between the number of trees and diameter class forming an inverted "J" curve (negative exponent). The distribution of puspa in the research plot shows a clustered distribution. This has a good impact on the natural regeneration process. All biophysical aspects measured in the research plots were relatively uniform.
Keyword: puspa, regeneration, TNGHS, vegetation analysis

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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