The partition function has been determined for fine coal in a dense-medium cyclone. The partition curve is characterised by four parameters; the cut point, the separation efficiency, the short circuit to underflow and the short circuit to overflow. Each of these parameters is a strong function of particle size for fine coal. The effect of slimes in the feed is shown to have only a small effect on the measured partition curves

Performance of a Dense-Medium Cyclone When Beneficiating Fine Coal

. Cahyanto T, Efendi M, Shofara RM. 2019. Short Communication: Floristic survey of vascular plant in the submontane forest of Mt. Burangrang Nature Reserve, West Java, Indonesia. Biodiversitas 20: 2197-2205. A floristic survey was conducted in submontane forest of Block Pulus ??Mount Burangrang West Java. The objectives of the study were to inventory vascular plant and do quantitative measurements of floristic composition as well as their structure vegetation in the submontane forest of Nature Reserves Mt. Burangrang, Purwakarta West Java. Samples were recorded using exploration methods, in the hiking traill of Mt. Burangrang, from 946 to 1110 m asl. Vegetation analysis was done using sampling plots methods, with plot size of 500 m2 in four locations. Result was that 208 species of vascular plant consisting of basal family of angiosperm (1 species), magnoliids (21 species), monocots (33 species), eudicots (1 species), superrosids (1 species), rosids (74 species), superasterids (5 species), and asterids (47), added with 25 species of pterydophytes were found in the area. The three families of plants are Lauraceae (10 species), Urticaceae (9 species), and Rubiaceae (8 species) dominating those areas. Fourteen species belong to IUCN red list: Least concern/LC (12 species), Vulnerable/VU (1 species), and endangered/EN (1 species). Furthermore, Castanopsis argentea A.DC, Pinanga javana Blume and Amorphophallus decus-silvae Backer & Aldrew belonging to protected plants are also found in the area. Based on the assessment of analysis vegetation, the forest has experienced disturbance, the density of trees is commonly  low and has a lot of gaps. Many vacant lots are found. On the other side, there is the presence of invasive plant species that may slow down a succession into climax growth of local plant.

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Short Communication: Floristic survey of vascular plant in the submontane forest of Mt. Burangrang Nature Reserve, West Java, Indonesia

Increased carbon dioxide in the atmosphere causes the surface temperature of the earth to warm up and has a major impact on climate change globally. Plants in the forest as the biggest absorber of carbon dioxide used in the process of photosynthesis, then the results are stored in the form of biomass in plant organ tissues. The purpose of the study was to estimate biomass and carbon storage in the Mount Tampomas Protected Forest Area in Sumedang, West Java. Mount Tampomas protected forest area is divided into areas dominated by pine plant species (Pinus merkusii) and mixed jungles. In the two regions the NDVI class was classified into 5 classes as the basis for calculating the stand density, biomass and carbon storage. The relationship between NDVI classes and stand densities can be demonstrated by linear and quadratic regression models. The quadratic regression model has r of 0.79 while the linear regression model of 0.78. Quadratic regression model is the best model to connect the NDVI class and stand density, where the NDVI class and stand density are very strongly related. The total biomass and carbon deposits sequentially in protected forest areas dominated by pine are 132,613.79 tons and 62,328.48 tons C, while the total biomass and carbon deposits sequentially in mixed forest protected areas are 64,682.95 tons and 30,400.99 tons C, so that the total biomass and carbon storage sequentially in the Mount Tampomas Protected Forest Area are 197,296.74 tons and 92,729.47 tons C.

Estimation of biomass and carbon deposits in the Mount Tampomas Sumedang protected forest area in West Java

. Cahyanto T, Efendi M, Ramdan DM. 2020. Structure and composition of trees in Mount Tilu Nature Reserve, West Java, Indonesia. Biodiversitas 21: 2674-2680. An understanding of the structure and composition of stands in a conservation area is needed to support sustainable management strategy. However, this information in the Mount Tilu Nature Reserve, Bandung District, West Java area is still lacking. This research was aimed to analyze the structure and composition of tree species in the block of Malagembol forest, Mt. Tilu NR. Data collection was carried out through vegetation analysis using sampling plot method with size of 10x100 m2 at three-level altitudes of 1530 m, 1745 m, and 1950 m asl. Observation parameters included species names, number of individuals, and diameter at breast height (dbh). Data were analyzed to determine the floristic composition, species structure based on their diameter class, relative basal area, diversity indices, and analysis of the importance of the main components of trees species through Principal Component Analysis (PCA). A total of 32 tree species from 23 families was found in the observation plots which was dominated by Fagaceae, Lauraceae, and Myrtaceae families. Some pioneer plants covered the gap in vegetation due to minor disturbance and residual damage in the past. Nonetheless, the dominance of stands with small diameters indicated good regeneration status following such disturbance. Based on these findings, we recommend protecting the vegetation in Mt. Tilu NR by limiting community activities that can disturb the forest.

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Structure and composition of trees in Mount Tilu Nature Reserve, West Java, Indonesia

Soil organic matter is an indicator of soil fertility. The purpose of this study was to analyse various forms of soil organic carbon in citronella plantation, citronella plantation under pine tree, and soil under pine tree. Soil organic carbon in various forms was analysed from soil samples taken from each horizon and soil profile. The soil profiles observed were ultisol profiles planted with citronella, citronella under pine tree, and under pine tree, and slopes; 0-8%, 8-15%, 15 -25%, and 25-40%, in order to obtain 12 soil profiles with a total of 39 soil samples. Ultisols planted with citronella had higher soil organic carbon than ultisols planted with citronella under pine tree and ultisols under pine trees. Based on the slope, the highest soil organic carbon was obtained in the soil with a slope of 0-8%, and decreased with increasing slope. Based on soil depth, the highest soil organic carbon was obtained in the upper horizon, compared to the horizon below. The highest total soil organic carbon was obtained at the soil surface horizon with a slope of 0-8% and citronella was planted. This pattern of total soil organic carbon is similar to that of sesquioxide bound organic carbon, but is not consistent with that of free clay bound organic carbon.

https://doi.org/10.1088/1755-1315/951/1/012009

Distribution of organic carbon in Ultisol soils with citronella and pine vegetation, at Gayo Highlands, Aceh

PURWANINGSIH, POLOSOKAN, R., YUSUF, R. & KARTAWINATA, K. 2017. Phytosociological study of the montane forest on the south slope of Mt. Wilis, East Java. Indonesia. Reinwardtia 16(1): 31 - 45. —A phytosociological stud y of a montane forest was carried out on the south slope of Mount Wilis, Kediri, East Java. The objective of the study was to do quantitative measurements of floristic composition and structure of the montane forest located within the seasonally dry climatic region as to date no such study has been undertaken there. It was conducted using the quadrat method by establishing plots of 2500 m2 each at five locations at the altitudes of 1100 m asl (above sea level), 1200 m asl, 1300 m asl, 1400 m asl and 1500 m asl, thus the total area sampled was 1.25 ha. They were Plot1100 at Bekayang, Plot1200 at Bukit Bendera, Plot1300 at Batutulis, Plot1400 at Mergosepi and Plot1500 at Brak. A total of 1045 trees comprising 74 species of 50 genera and 33 families were recorded. Based on a species constancy index of 100 %, the Saurauia nudiflora-Weinmannia blumei association was established. The association consisted of (1) the Cyathea-Polycias subassociation, representing the heavily disturbed forest, currently dominated by Cyathea contaminans and (2) the Villebrunea-Syzygium subassociation, representing the least disturbed forests, dominated by Syzygium lineatum and Villebrunea rubescens. The lowest number of species (13) was recorded in Plot1100 and the highest number (39) in Plot1300. Important species recorded included Cyathea contaminans (Importance Value, IV= 47.97); Lithocarpus sp. (IV= 22.07); Lithocarpus sundaicus (IV= 14.05); Saurauia pendula (IV= 12.85); Villebrunea rubescens (IV= 12.12) and Syzygium lineatum (IV= 11.22). Diameter measurements showed that 76.60 % of trees in Plot1100 and 86.60 % in Plot1200 consist of small individuals with diameters between 10 and 30 cm. Trees with large diameters of >30 cm occurred in Plot1300, Plot1400 and Plot1500. The presence of large numbers of small trees and lesser numbers of trees with large diameters in a forest stand indicated that the stand was regenerating after heavy disturbance. The presence of the majority of trees with height of < 20 m (99 %) further confirmed the forest’s dynamic status.

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Phytosociological study of the montane forest on the south slope of mt. wilis, east java, indonesia

Fagaceae umumnya pohon, salah satu suku dengan jumlah jenis yang cukup besar ± 700 jenis di dunia tetapi sebagian besar tumbuh di belahan bumi utara. Di wilayah Malesia, ada lima marga yaitu Nothofagus, Castanopsis, Lithocarpus, Quercus dan Trigonobalanus dan jumlah jenis ± 180 dan sebagian besar di Indonesia tercatat 112 jenis. Penelitian ini dilakukan dengan studi literatur untuk menentukan keanekaragaman jenis Fagaceae di Indonesia serta distribusi dan pemanfaatannya. Fagaceae paling banyak tumbuh di Indonesia adalah marga Lithocarpus (60 jenis) dan Castanopsis (24 jenis), sementara Nothofagus (11 jenis) sebarannya hanya di Papua. Distribusi jenis Lithocarpus paling di Sumatera (29 jenis) dan Kalimantan (26 jenis), sementara Castanopsis paling banyak di Kalimantan (15 jenis). Untuk Nusa Tenggara tidak ditemukan jenis-jenis Fagaceae dan ke arah timur Indonesia semakin sedikit jumlah jenisnya, di Sulawesi dan Maluku hanya diketemukan satu jenis. Sebaran Fagaceae dipengaruhi oleh beberapa faktor, terutama tanah, iklim, dan ketinggian. Di Indonesia habitat tumbuh Fagaceae di hutan yang masih alami, tetapi ada beberapa yang mampu tumbuh di rawa seperti Nothofagus womersleyi. Berdasarkan ketinggian tempat (altitude) umumnya Fagaceae di hutan submontane dengan ketinggian 600-1500 m namun ada beberapa spesies yang mampu tumbuh hingga ketinggian >3000 m. Fagaceae yang memiliki sebaran luas (ditemukan di beberapa pulau) ada dua jenis yaitu Castanopsis acuminatissima dan Lithocarpus elegans. Pada umumnya pemanfaatan Fagaceae adalah kayunya untuk bahan bangunan dan furniture tetapi ada jenis Castanopsis yang dapat dimakan bijinya dan selain itu kulit kayu mengandung tanin bisa untuk pewarna.

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Keanekaragaman jenis dan sebaran fagaceae di indonesia

A study on the biomass and carbon stock estimation of Pinus merkusii Jungh. & de Vriese plantation has been conducted on 17-years and 30-years old pine forest in Gunung Bunder, Halimun Salak National Park. The method used was the allometric with non destructive technique. The results showed that pine trees density of 30-years old pine was 542 trees ha-1 ; the basal area (BA) was 26.8 m2 ha-1; trees density of 17-years old pine was 1,398 tree ha-1 with BA was 36.2 m2 ha-1. The estimation of biomass, carbon sinks and CO2 sequestration of 30-years old pine were 203.7, 96.5 and 354.2 ton ha-1, respectively. Meanwhile, the estimation of biomass, carbon sinks and CO2 sequestration of 17-years old pine were 188.3, 86.8 and 318.5 ton ha-1, respectively. Value of the environmental services derived from the CO2 absorption for the development of a pine forest ranged from US.$ 1,847.09 to 2,054.22, at two ages of pine trees.

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ESTIMASI BIOMASA DAN KARBON TERSIMPAN PADA Pinus merkusii Jungh. & de Vriese DI HUTAN PINUS GN. BUNDER, TN. GN. HALIMUN SALAK

Dungus Iwul Nature Reserve is one of the remaining conservation areas in Java and has an unique vegetation. Study on tree biodiversity was carried out in one hectare permanent plot. The results showed that there were 78 species of 35 families and 63 genera with 1219 trees per hectare. The species of Orania sylvicola was very dominating the region, with high distribution (Frequency = 100%) and the total basal area (basal area relative; BA = 50.96%). Species of O. sylvicola (Important Value; IV = 129.48%) highly covered the area, followed by Mischocarpus sundaicus (IV = 19.93%), Diospyros frutescens (IV = 9.67%), Ficus variegata (IV = 9.38%) and Knema laurina (IV = 8.51%). Family with largest number of species was Euphorbiaceae (11 species), followed by Lauraceae (7 species) and 4 species of Fabaceae, Meliaceae and Rubiaceae.

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Ruddy Polosakan

Papers

Phytosociological study of the montane forest on the south slope of mt. wilis, east java, indonesia

Keanekaragaman jenis dan sebaran fagaceae di indonesia

ESTIMASI BIOMASA DAN KARBON TERSIMPAN PADA Pinus merkusii Jungh. & de Vriese DI HUTAN PINUS GN. BUNDER, TN. GN. HALIMUN SALAK

Keanekaragaman jenis pohon di kawasan cagar alam dungus iwul, jasinga, bogor

Coal preparation and use: a world review