BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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DOMINANCE, ASSOCIATION AND DISTRIBUTION PATTERN OF TREE SPECIES IN BURNT FOREST IN EAST KALIMANTAN
Get PDFRepeated forest fires remarkably impact species composition. Pioneer species colonize the burnt forest and widely develop up to 30 years after a fire, but late-succession species regenerate gradually or even disappear owing to direct impact of fires or other ecological consequences related to fires. Hence, forest restoration through assisted natural regeneration needs some information about the state of post-fire species composition. To better evaluate tree species composition after repeated fires, the species dominance as an indicator of species composition was used in this research, with additional information on the species association and distribution patterns. A 1.8-hectare plot, divided into 180 subplots with a size of 10 × 10 m, was established in a secondary forest in Samboja Research Forest, East Kalimantan. The sample plot was burnt in 1982/1983 and 1997/1998. All trees above 10 cm DBH were measured and leaf specimens were collected for species identification at the Herbarium Bogoriense, Cibinong, West Java. For comparison, the 1981 data from the Indonesian Institute of Sciences were used. Analysis of the Importance Value Index used the species dominance data. A 2 × 2 matrix based on the presence–absence of species for each subplot was used to analyze the association index among species. Variance and average value ratio of certain species present in each subplot were expressed in a dispersion index. A chi-square was used to test the significance between the association and dispersion index. Thirteen years after a second fire, pioneer species Macaranga gigantea were most dominant, followed by Vernonia arborea, a sub-climax species. This indicated that the forest was in an early succession process. Pholidocarpus majadum was consistently dominant before and after the fire. A total of 38 pairs of species were significantly positively associated and 4801 pairs negatively associated. About 60% of species association, both negatively and positively, were among the "native species" (species that existed before the fire events) and "non-native species" (newcomer species that regenerated after the fire) in the plot sample. A non-native species, Vernonia arborea, associated negatively with the non-native species Tabernaemontana spireumcama, and native species Oncosperma horridum, Palaquium and Endiandra rubescens. The distribution pattern of four native species, Artocarpus, Cananga odorata, Croton laevifolius and Macaranga gigantea, changed after repeated fires, from uniform to clumped
LAND SUITABILITY ASSESSMENT FOR PATCHOULI (Pogostemon cablin) DEVELOPMENT AND ESSENTIAL OIL PRODUCTION
Get PDFThe conformity of abiotic factors in the growing environment of crops determines the successful result of crop production. This study aims to assess and evaluate land suitability for plant growth and result of patchouli development in Dilem wilis, Bendungan Distric, Trenggalek Regency. The study was initiated with the survey and continued by utilizing analysis method to adjust the data with the criteria according to the classification of land suitability clashing and crops cultivation as indicator for assessing land suitability. The research was conducted on 3 locations from May to July 2017 for land suitability and from July to November 2017 for patchouli crops cultivation experiment. The result indicated from the three sampling Locations, specifically Location 1 presented the land suitability of N class, conforming that this Location was not suitable with the limiting factor of low K2O content of 0.08 me / 100 g. Meanwhile, both Location 2 and Location 3 presented similar land suitability class of S3s, tc, f, n conforming as less appropriate. The results of this study also depicted the influence of land suitability classes on plant growth; however, the difference in land classes (in this case S3 compared to N) did not demonstrate a correlation for oil yield and patchouli alcohol, where the element Potassium becomes a limiting factor
INTERLEUKIN LEVELS IN THE Zingiber cassumunar-TREATED MICE
Get PDFThe cytokine is one of the proteins responsible for the immune system. Several types of cytokines acting as key regulators of infection include IL-10, IL-12, and IL-14. The chemical content of Zingiber cassumunar shows potential immunomodulatory effects. This study aimed to determine the effect of the ethanol extract of Zingiber cassumunar (EEZC) on the expressions of IL-10, IL-12, and IL-14. The test animals were BALB/c mice, which were divided into five groups, i.e., normal group (untreated), negative control group (treated with 10% of tween 80), and three treatment groups that respectively received 1.25 mg, 2.5mg, and 5mg/20g BW of EEZC. The treatment was carried out for 21 days. On the 22ndday, the mice were induced with LPS intraperitoneally (except for the normal group). The interleukin expression was observed by immunohistochemistry using specific antibodies, and the expressed cells were counted under a microscope. The administration of EEZC at the doses of 1.25 mg, 2.5mg, and 5mg/20g BW for 21 days increased the expression of IL-10, IL-12, and IL-14 significantly and proportionally to the dose. and suggested the potency of extract to induce both innate and adaptive immunity. This activity may be attributable to curcumin as an active compound in this extract
DEVELOPMENT OF WOODCERAMICS FROM TROPICAL FLORA
Get PDFWoodceramics are porous carbon or hybrid materials derived from woody materials impregnated with thermosetting resin and vacuum-carbonized at high temperatures. Woodceramics have become commercially valuable due to their applications in heaters, gas filters, absorbents, and humidity and temperature sensors. Hence, this study aimed to determine the suitable conditions for producing woodceramics from various materials and to evaluate their potential applications. The specific surface area (SSA), pore volume, pore diameter, and adsorption isotherm of woodceramics made from bamboo, pine, eucalyptus, rubberwood, and oil palm shell particleboards were obtained using the Brunauer–Emmett–Teller (BET) method. The average pore diameter was classified as mesoporous (2–50 nm). The SSA and adsorption isotherm results of the woodceramics made from eucalyptus indicated that this species can be used as activated charcoal, and its volume electrical resistivity was similar to that of a semiconductor. When carbonized at maximum temperatures of 800 °C and 1,000 °C, the electromagnetic shielding effectiveness (ESE) of the woodceramics ranged from approximately 20–60 dB within a frequency range of 800–2,200 MHz. This ESE value was higher than those of materials woven from boron carbon fiber, carbon boron, and stainless steel fiber-filled thermoplastics. Moreover, the production cost of woodceramics was lower compared to commercial alternatives
PREVENTION METHODS AGAINST Aeromonas hydrophila AND Pseudomonas fluorescens INFECTION IN TILAPIA
Get PDFThis research evaluated a method involving provision of a concoction of Boesenbergia pandurata, Solanum ferox dan Zingimber zerumbet extracts for pathogen prevention in tilapia. The concentration of each extract was 600 ppm of Boesenbergia pandurata/BP, 900 ppm of Solanum ferox/SF and 200 ppm of Zingimber zerumbet/ZZ. The examination was performed by issuing two combinations of extracts (SF:BP, SF:ZZ) against Aeromonas hydrophila and Pseudomonas fluorescens (105 CFUmL-1). Preventive trials were carried out by providing a concoction of extracts through intraperitoneal injection (0.1 mL/fish) in tilapia (15±2 g) and the immersion method was performed by bathing the fish in the extracts for 20 minutes, with pathogen challenging during the following 24 h being carried out. The composition of the used extract was by SF60:ZZ40; SF50:ZZ50; BP90:SF10; BP50:SF50; and fish without being given the extract. Haematology and immunology parameters were observed at the 4th week after challanges with pathogenic bacteria. The number of white blood cells (WBCs) increased significantly (P <0.05) compared to controls without extract, with a similar increase observed for red blood cell (RBCs), but heamatocrit (Ht) and hemoglobin (Hb) values did not significantly increase compared to control. Phagocytic index, respiratory burst and lysozyme activities also experienced a significant increase in fish fed with combined extracts compared to controls. The numbers of pathogenic bacteria in the body of the fish given extract were also lower than the control and significantly different at the 4th week. The results of this study indicate that giving combined extracts of SF50:ZZ50 and BP90:SF10 provides the best protection (RPS) against infection of A. hydrophila and P. fluorescent by injection of 100%. This study indicates that providing combined extracts by injection and immersion in the ratio of SF50:ZZ50 has a positive effect in increasing the non-specific immune system of tilapia and increasing protection against bacterial infections
SOIL PROPERTIES BELOW EXOTIC TREE PLANTATIONS AT THE SAITHONG SILVICULTURAL RESEARCH STATION IN PRACHUAP KHIRI KHAN PROVINCE, THAILAND
Get PDFOften, exotic trees grow very fast in their new environments and sometimes even faster than the indigenous ones. These exotics seem to be tougher and able to live through harsher conditions. They may be drought-resistant and can survive long periods with little to no rainfall. These trees are fast-growing and resistant to pests and diseases that tend to damage locally growing trees. Moreover, these trees can help improve soil physical and chemical properties. Hence, the objective of this study was to compare the physical and chemical properties of soils under different tree plantations, namely Eucalyptus urophylla, Acacia crassicarpa, and Acacia auriculiformis at the Saithong Silvicultural Research Station. Three composite soil samples were collected from depths of 0–10, 10–30, and 30–50 cm in the three stands aged 27 years and planted at a spacing of 2 × 2 m. The soil type in these stands was sandy loam. Soil moisture percentage (12.85%) was significantly the highest in the E. urophylla plantation. Phosphorus (18.2 mg/kg), magnesium (6.98 cmolc/kg DW), and potassium (6.98 cmolc/kg DW) contents were also the greatest in the E. urophylla plantation. Organic matter content was the highest in the A. crassicarpa plantation (7.59%), while nitrogen (0.04%) and calcium (36.17 cmolc/kg DW) contents were the highest in the A. auriculiformis plantation. Significant differences were also observed in soil bulk density and porosity attributable to structure, tillage, cropping practices, soil depth, and compaction. Characterization of the soil pore system is equally important in understanding soil physical properties and parent material composition, which has a direct impact on soil chemistry and fertility. Parent material rich in soluble ions (calcium, magnesium, potassium, and sodium) is desirable, as these elements are easily dissolved in water and readily available for plants. For soils with poor nutrient content found in warm and humid tropical climates with low water supply, E. urophylla, A. crassicarpa, and A. auriculiformis have the potential to enhance aboveground stand production. Undoubtedly, when planted, they can help restore soil nutrients faster and therefore can be used in forest plantations or agroforestry farms
HYPER-SOLUBILIZING TRICALCIUM PHOSPHATE MUTANTS OF Klebsiella sp. GMD08
Get PDFKlebsiella sp. GMD08 is a bacterium capable of dissolving insoluble inorganic phosphate into soluble phosphate ions through its organic acid production. Transposon is a genetic element commonly used to generate mutants through mutagenesis, and thus can be used to identify genetic functions involved in phosphate-solubilizing mechanisms. This research was conducted to identify the genes of Klebsiella sp. GMD08 involved in phosphate solubilization through sequence detection obtained from a hyper-solubilizing phosphate mutant library. Mutation was carried out by inserting a mini-Tn5 transposon hosted in Escherichia coli S17-1/λpir [pBSL202] into the chromosome of Klebsiella sp. GMD08 using the filter mating conjugation method. Transconjugant mutant candidates were then qualitatively and quantitatively analyzed for their ability to dissolve tricalcium phosphate [Ca₃(PO₄)₂] using Pikovskaya medium. The organic acid profiles of the transconjugant mutants were detected using High-Performance Liquid Chromatography (HPLC). Suspected genes involved in phosphate solubilization were identified through sequencing of transposon insertion sites. Nucleotide BLAST was used to determine nucleotide sequence similarity with the database. The results showed that PB116 and PB122 were the two main transconjugant mutants obtained from transposon mutagenesis with higher tricalcium phosphate-dissolving ability. Gluconic acid was identified as the main organic acid produced by Klebsiella sp. GMD08 in its phosphate-solubilizing mechanism. Furthermore, the arginine repressor (ArgR) and malate dehydrogenase (mdh) genes were found to be involved in the phosphate-solubilizing mechanism of Klebsiella sp. GMD08
EFFECTS OF FIRE ON STRUCTURE AND COMPOSITION OF VEGETATION COMMUNITY IN PINE FORESTS, NAM NAO NATIONAL PARK, THAILAND
Get PDFAnthropogenic forest fires, including those occurring in the pine forests of Thailand, have been widely reported. Although pine forests are fire-dependent, too frequent burning could be unhealthy for the forest as it might result in nutrient depletion and ecosystem degradation. Hence, this study aimed to examine the effects of forest fire on the vegetation structure and composition of a degraded pine forest (PF) and a mixed pine-oak forest (O-PF) in Phu Kum Khao, Nam Nao National Park, Phetchabun Province, Thailand. The effects of fire over one year were studied using three 50 × 50 m experimental plots established in each forest type. Results showed that fire events caused a significantly higher tree mortality rate in the degraded pine forest than in the mixed pine-oak forest. Moreover, the seedling ratio (number of sprouts to number of seedlings) in the mixed pine-oak forest was higher than in the degraded pine forest. Although the sapling and seedling diameters were slightly different between the sites, no significant effect of burning was observed on sapling and seedling density, diameter, or height. This might be due to the high variation of fire behavior in each plot. Since forest fires are a potential factor contributing to forest degradation in the study area, further studies on the effects of fire frequency on vegetation structure and composition are needed to provide sufficient control measures for efficient forest fire management and prevent further ecosystem degradation
DIVERSITY AND ECOLOGY OF UNDERSTORY PLANT IN SEMPU ISLAND, EAST JAVA, INDONESIA
No full textAs an indicator of environmental disturbances, the understory is an important structural and functional component of forest ecosystems. Hence, this study was conducted to assess the diversity and composition of understory plants in the lowland forests adjacent to the trekking paths along Semut Bay (dock entrance), Segara Anakan Lagoon, and several coastal areas in Sempu Island, and to determine their relationship with the underlying environmental factors as disturbance indicators through the presence of understory invasive alien species (IAS). Sixty site plots of 2 × 2 m² were established to analyze the understory vegetation, site profiles, and environmental variables. A total of 135 understory plant species belonging to 108 genera and 60 families were recorded within the 60 plots of the study areas. Poaceae was the dominant family, followed by Compositae, Phyllanthaceae, Sterculiaceae, Rubiaceae, Putranjivaceae, and Cyperaceae. The understory communities in the lowland forest adjacent to Semut Path were dominated by tree seedlings and had a relatively lower composition of shrubs. Coastal areas, which have more open canopies, were dominated by grasses and shrubs. Some dominant native understory species included Grewia spp., Cycas rumphii, and others. Indicating disturbance, 12 understory IAS were found in the study areas. Four of these are among the world’s worst invaders (Ageratum conyzoides, Chromolaena odorata, Lantana camara, Mikania micrantha), and three are noxious weeds (Eleusine indica and Imperata cylindrica). Light intensity and air temperature were strongly and positively associated with disturbed sites, while relative humidity, soil pH, and elevation were associated with less disturbed sites. The study results provide a scientific basis and recommendations on the current diversity status of understory plant species at Sempu Island, helping justify further conservation of indigenous species and their protection from disturbances
PHYTASE PRODUCTION BY Enterobacter cloacae
Get PDFThis study aims to isolate phytase-producing bacteria (PPB), a type of plant growth-promoting rhizobacteria (PGPR), from the Vigna sinensis rhizosphere and to optimize their physicochemical conditions. Phytase is an enzyme that hydrolyzes the phosphoester bonds in organic phosphorus (phytic acid) to release ester phosphate and inorganic phosphate, the bioavailable forms of phosphorus. To test their ability to hydrolyze organic phosphates (calcium phytate), phytase activity was screened using solid and liquid phytase screening medium (PSM). A total of 13 isolates tested positive for phytase production, indicated by clear hydrolysis zones surrounding the colonies. Enterobacter cloacae strain B1 exhibited the highest hydrolysis efficiency (3.43) on solid medium. The phytase produced by E. cloacae strain B1 in liquid PSM reached 0.92 U/mL after 48 hours of incubation. This strain produced optimal phytase levels in the presence of lactose and monoammonium phosphate (NH₄H₂PO₄) as carbon and nitrogen sources, respectively, at 30 °C and pH 5.0. The PPB obtained in this study are recommended for further research regarding their potential use as biological fertilizers for plants