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HUBUNGAN KETAHANAN KAYU TERHADAP JAMUR DENGAN KERAPATAN DAN PENGKARATAN LOGAM
No full textWood constructions are mostly fastened by metal screw or metal fastener, then corrosion resistance is an importantfactor. Wood natural durability against fungus and its relation to basic density are two other factors affecting woodquality for construction. This paper studies wood natural durability against fungus and metal corrosion in relation todensity of five Riau wood species. Wood samples were tested against fungus using the Kolle-flask method and wooddensity was measured based on DIN-2135-1975 standard. Result shows that Diospyros korthalsiana wood wascategorized as non-resistant (class IV), Tetramerista glabra wood was classified as moderately resistant (class III),while Shorea teysmanniana, Palaquium burckii, and Aglaia argentea woods are grouped into resistant wood(class II). In all wood species, weight lost of heartwood is lower than that of sapwood, but in the same durabilitygroup (moderately resistant). In general, there is a relationship between density and weight loss. The higher the wooddensity is the lower the weight loss. The average of weight loss of metal screwed wood is higher than wood withoutscrews. The highest weight loss was recorded from Palaquium burckii wood which was screwed and exposed toPolyporus sp., while, the highest screw weight loss was recorded from Shorea teysmanniana wood exposed toPycnoporus sanguineus. Rustic enamel was highly recorded from Tetramerista glabra wood, which was exposedinto Tyromyces palustris. Eight species of fungus are moderate and two species are low in capability of decayingwood. The highest decaying ability in corroding metal screws is found in P. sanguineus. The weight of rustic enamelfound in the metal screw caused by four fungus activity of (Chaetomium globosum, P. sanguineus, S. communeand T. palustris) was relatively similar
PERBANDINGAN CIRI ANATOMI KAYU DAN KULIT 3 JENIS PULAI (Alstonia sp.)
No full textPulai (Alstonia sp.) belonging to the family Apocynaceae, produces latex which is frequently used as a traditional medicine. Various literatures on medicinal tree species frequently mention about it, but a description of the wood and bark anatomy of pulai up to the species level is hardly found. Anatomical structure of wood and bark of Alstonia scholaris, A. angustiloba and A. pneumatophora were observed on samples produced using a microtome. Dimensions of wood fiber and vessel cells also were measured. Observations showed that the three species of pulai wood can be distinguished from the differences in diameter and frequency of vessel cells, type and arrangement of parenchyma cells, width and composition of the ray cells. The bark of these species can be distinguisbed based on the form of sklereid cells and the presence of dilationed ray cells (widening ray cell)
KEANEKARAGAMAN NEPENTHES DI KAWASAN BUKIT PERASAK KABUPATEN SAMBAS KALIMANTAN BARAT
No full textNepenthes memiliki peranan penting dalam suatu ekosistem, di antaranya dapat mengendalikan populasi serangga serta mengurangi konsentrasi CO2 di udara karena laju fotosintesisnya yang cukup tinggi. Namun populasi tumbuhan Nepenthes terus menurun di habitat alaminya. Di Kalimantan Barat, khususnya Kabupaten Sambas, Nepenthes dapat ditemukan di beberapa tempat seperti di kawasan Bukit Perasak, Desa Seberkat. Tujuan dari penelitian ini adalah untuk mengetahui keanekaragaman spesies Nepenthes di kawasan Bukit Perasak Kabupaten Sambas. Metode penelitian yang digunakan adalah metode deskriptif. Pengamatan dilakukan di tiga titik Kawasan penelitian, yaitu hutan sekunder, areal terbuka, dan hutan kerangas dengan menggunakan teknik petak ganda. Pengukuran faktor lingkungan pada habitat Nepenthes seperti suhu udara, kelembaban udara, pH tanah dilakukan. Berdasarkan hasil penelitian diperoleh tiga spesies Nepenthes, yaitu Nepenthes gracilis, Nepenthes mirabilis, dan Nepenthes x neglecta. Spesies Nepenthes yang mendominasi di hutan sekunder adalah Nepenthes gracilis dengan INP (Indeks Nilai Penting) 119%, KR (Kerapatan Relatif) 59%, dan FR (Frekuensi Relatif) 60%. Di areal terbuka, yang mendominasi adalah Nepenthes mirabilis dengan INP 106%, KR 55%, dan FR 51%. Di Hutan Kerangas yang mendominasi adalah Nepenthes mirabilis dengan INP 111%, KR 58%, dan FR 53%. Faktor lingkungan pada habitat Nepenthes adalah suhu udara yang berkisar 25,1℃-32,1℃, kelembaban udara yaitu 79%-87,5%, dan pH 5,6-6,3
THE GENUS BUNCHOSIA RICH. EX KUNTH (MALPIGHIACEAE) IN JAVA, INDONESIA
No full textMalpighiaceae Juss. is a diverse family consisting of 72 genera that primarily distributed in tropical and subtropical regions. In Java, eight genera had been previously recorded. During fieldwork in 2024, a newly recorded genus, Bunchosia Rich. ex Kunth, was discovered in West Java (Sumedang) and East Java (Malang). This marks the first report of Bunchosia in Java, increasing the island’s known Malpighiaceae genera to nine. The genus is represented by a single species, Bunchosia armeniaca DC., locally known as kacang brazil. Native to Southern Tropical America, it was recently introduced to Java as an ornamental but is also valued for its edible fruit and seeds. This study provides an updated taxonomic key to the genera of Malpighiaceae in Java, along with a description of B. armeniaca and a discussion of its botanical significance
UNCOVERING TAXONOMIC CONFUSION IN COSTUS: MOLECULAR EVIDENCE FOR MISIDENTIFICATION BETWEEN C. afer AND C. lucanusianus IN THE BOGOR BOTANIC GARDEN LIVING COLLECTION
No full textAccurate species identification is critical for the integrity of botanical collections, especially when morphological similarities lead to taxonomic confusion. This study investigates the misidentification between Costus afer and C. lucanusianus in the living collection of the Bogor Botanic Garden using molecular evidence. Leaf samples of both taxa were subjected to DNA extraction, PCR amplification of the ITS region, and Sanger sequencing. BLAST analysis confirmed all sequences belonged to the genus Costus, with high identity scores and E-values of 0.0, indicating significant homology. Sequence alignment revealed 208 variable and 500 conserved sites across 731 bp. Phylogenetic analysis using the Maximum Likelihood method (MEGA 12) showed that both Bogor accessions clustered within the C. afer clade. Notably, the sample labeled C. lucanusianus grouped with C. afer (AY972934.1 and KJ011425.1), suggesting misidentification. These results are consistent with previous morphological assessments and highlight the effectiveness of DNA barcoding in resolving taxonomic ambiguities. The study underscores the importance of molecular verification in botanical gardens to support accurate species documentation and conservation
Revealing An Examination of the Javanese People's Perspective on Uba Rampe of Traditional Marriage in Kendal Regency, Central Java
No full textMarriage is a fundamental aspect of the human life cycle, serving not only as a sacred union between two individuals but also as a cultural tradition rich in symbolism and profound philosophical meanings passed down through generations. In Javanese culture, wedding ceremonies are more than mere rituals; they embody complex philosophies reflected through various elements called 'ubarampe' or ceremonial accessories used during traditional wedding processions. These ubarampe consist of various items that carry specific symbolic functions, collectively demonstrating the synergy of cultural and philosophical values within the community, especially in Boja Village, Kendal, Central Java. They serve as representations of the relationship between humans, nature, and divine principles, emphasizing harmony and balance—core concepts in Javanese cosmology—where elements such as water, fire, earth, and air symbolize fundamental aspects of life and the universe. Notably, earth and water dominate the ubarampe, symbolizing stability, fertility, and continuity, reflecting the community's view that success and harmony in marriage depend on maintaining equilibrium among these elements. This philosophy underscores the importance of humans aligning themselves with natural forces to achieve a harmonious and blessed life. Studying these symbols and their meanings reveals how traditional cultural practices strengthen local identity, preserve heritage, and foster a deeper understanding of life’s interconnectedness, emphasizing that cultural preservation is vital for sustaining community identity and ensuring the continuity of ancestral wisdom in contemporary society
PENGARUH PERBAIKAN METODE PEMBAGIAN BATANG TERHADAP WAKTU KERJA DAN PRODUKTIVITAS PENEBANGAN HUTAN ALAM PRODUKSI: STUDI KASUS DI PT. DWIMAJAYA UTAMA
No full textThe improvement of bucking method in tree felling was examined to observe harvesting efficiency in natural production forest. This paper studies distribution of work time elements, productivity, and efficiency of timber utilization in accord with application of bucking system improvement. Research was conducted in natural forest production concession of PT. Dwima Jaya Utama in Central Kalimantan. The study was conducted using four research sample plots (PCP) measuring of 100 m x 200 m which were placed intentionally (purposive) on selected cutting plots. Two PCPs were used for the conventional logging treatment (CV) and the remaining plots were allocated for the improving stem distribution methods (IBM). Data analysis was performed statistically using PWSTAT version 23.0. Results showed that the CV method’s working time of 14.6 minutes/tree was not significantly different with that of IBM working time of 15.5 min/tree. Wood utilization efficiency of IBM was 93.1%, which was higher than that of the conventional method (CV) of 85.4 %. However, the productivity of IBM was 27.161 m3/hour, which was lower than that of the CV method of 32.847 m3/hour
SINTESIS, KARAKTERISASI DAN APLIKASI BIO-IMPREGNAN DARI KULIT BATANG SAWIT
No full textThe formulation of phenolic compounds extracted from biomass not only produces adhesives but can also be used as bioimpregnant. In this study, the synthesis was carried out by copolymerization of resorcinol (R) and formaldehyde (F) into the oilpalm bark extract (S) to produce SRF resin fluid. A complete characterization was carried out using FTIR, Py-GCMS, XRDand DTA. In addition, F emission was also undertaken to ensure its safety for health and the environment. The application ofbio-impregnant was done on samples of the hard (edge) and soft (middle) parts of the oil palm trunk. The results show that the oilpalm bark extract contains polyphenol components that have a strong affinity for resorcinol and formaldehyde in alkaline catalyst(NaOH 40%), so that it can form a copolymer that can be used as an impregnant. The application of the bio-impregnant canimprove the quality of the oil palm trunk in both parts from class V to class III of wood-strength classification with an increase indensity (>100%), hardness (4 times), thickness swelling in both cold and boiling water meets the requirements (<25%), as wellas formaldehyde emission that meets the standard SNI 03-2105-2006
KARAKTERISTIK KARBON AKTIF DARI KULIT BUAH MALAPARI (Pongamia pinnata L. Pierre)
No full textVegetable oil production of malapari (Pongamia pinnata L. Pierre) fruit remains peels that haven't been utilized. Malaparifruit peel is potential for activated carbon. The purpose of this research is to use malapari fruit peel waste as raw material forproducing activated charcoal. Samples were carbonized at temperature of 400°C and continued activation with phosphoric acid2% and physical activation at temperature of 750°C by flowing steam for 60 minutes. The process resulted in the Optimumcondition. It yields 54% charcoal recovery, moisture content of 8.6%, volatile matter of 11.85%, ash content of 24.73%, fixedcarbon of 63.42%, benzene adsorptivity of 10.15%, metilene blue adsorptivity of 93.89 mg/g, iodine adsorptivity of 648.62mg/g, and specific surface area of 348.11 m2/g. Activated carbon in this study is below Indonesian standards, which is influencedby the activation retention time
UJI COBA REKAYASA ALAT UKUR DIAMETER POHON DI HUTAN ALAM
No full textTrial test of tree diameter measurement device ‘wesyano’ was conducted in 2016 at a natural forest in Central Kalimantan. This paper evaluates five main components of the measurement device: roller measurement, telescopic stick, frame shaft, lid-scale meter, scale-meter, and its locker. Result on single and double measurements showed that wesyano had an accuracy of 0.98–0.99 with an efficiency level of 1–4 times faster than the phi-band measurement. Validated results indicated that wesyano was highly correlated with phi-band measurement for single (r = 0.978) and double (r = 0.982) measurements. There is no significant differences between single and double measurements. The study indicates that wesyano could be used for phi-band measurement substitute. The device was more practice, cheaper and more effective to be used mainly for forest inventory in natural forests which contain large stem diameter (≥ 50–100) and high position of buttress, (≥1.8 m) with high accuracy, efficien of and low cost