BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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ECOLOGICAL EFFECTS OF BELIK RIVER HYDRAULIC CHARACTERISTICS ON PERIPHYTON COMMUNITY AS WATER QUALITY BIOINDICATOR
Get PDFARTICLE HIGLIGHTS- Differences in river hydraulic characteristics affect ecological river health- The influence of flooding on the dynamics of physical and chemical characteristics of river water- Life strategy, adaptation of periphyton to environmental changes- Development of green infrastructure for river conservationABSTRACTBelik River is one of the urban rivers in the Special Region of Yogyakarta which has hydrological problems both in quantity and quality. This triggered the construction of various types of channel modifications. This study aimed to identify water quality and the ecological effects of channel modifications based on the presence of periphyton communities as bioindicators. Sampling was carried out in January 2021 and March 2021. Samples were taken at 4 sampling sites with different channel characteristics with 3 repetitions at each location. The physico-chemical parameters measured included pH, detergent, nitrate, sulfate, total phosphate, TSS, TDS, DO, CO2, water temperature, depth, transparency, discharge, and current velocity. The results showed that the abundance of periphyton in January 2021 was higher than in March 2021. In January 2021 there were found 91 periphyton species dominated by Nitzschia improvisa, Nitzschia terricola, and Nitzschia philippinarum. Meanwhile, in March 2021 there were found 61 species of periphyton dominated by Nitzschia improvisa. Based on the results of Canonical Correlation Analysis (CCA), it was shown that in general the distribution and abundance of periphyton in the Belik River were influenced by CO2, total phosphate, discharge, DO, nitrate, TSS, and depth. The Shannon Wiener Diversity Index showed that water quality in January 2021 has decreased in March 2021. From the cluster analysis, it is known that there are differences in water quality and abundance of periphyton in the four types of river channels. It can be concluded that differences in hydraulic characteristics affected water quality and the ecological health of Belik River
EFFECT OF THINNING ON GROWTH AND WOOD PRODUCTION OF NATURALLY REGENERATED 8-YEAR-OLD ACACIA MANGIUM WILLD. PLANTATION ON ABANDONED MINING AREA, SOUTHERN THAILAND
Get PDFThinning is an important practice for promoting growth and maintaining forest plantation for wood production from the remaining trees. In this study, thinning was carried out in a naturally regenerated 8-year-old Acacia mangium plot in the Phangnga Forestry Research Station. Three thinning schemes, with 175 (T1), 300 (T2) and 600 (T3) remaining trees/ha, were compared with the control (no thinning) of 831 trees/ha. The diameter at breast height (DBH) and height (H) of the trees were measured. The differences in growth, current annual increment (CAI), aboveground biomass, and stem volume (V) were analyzed. We observed that the thinning of A. mangium increased the growth rate, with the DBH being clearly affected by thinning. CAIDBH increased significantly, with the DBH class of thinned A. mangium plots also improving after thinning. The stem volume and aboveground biomass of T3 plot was similar to the control plot after thinning. In addition, the number of large saw logs was the highest in T3 plot. The large saw logs can be used for multi-utilization and have a high value. These results suggest that thinning can promote stem growth, and increase the proportion of large saw logs in naturally regenerated A. mangium stands
THE CHEMICAL CHARACTERISTICS OF ARABICA AND ROBUSTA GREEN COFFEE BEANS FROM GEOPARK RINJANI, INDONESIA
Get PDFGreen coffee beans are also called unroasted coffee beans. The chemical composition of green coffee beans plays a vital role in determining the final product’s aroma. The main objective of this research was to characterize the chemical properties of Arabica and Robusta green coffee beans grown in different regions of Geopark Rinjani, Lombok Island, Indonesia. The water, ash, protein, carbohydrate, total solids, and caffeine contents, total acidity, and pH were determined. Data were analyzed by analysis of variance. The results revealed significant differences in the moisture contents of Arabica beans from Sembalun, Sajang, and Sapit and Robusta beans from Rempek, Selelos, and Genggelang. Additionally, the ash contents of Arabica Sajang and Arabica Sapit showed notable differences compared to other samples. However, the total fat contents of Arabica Sajang, Arabica Sapit, Robusta Rempek, and Robusta Genggelang did not exhibit significant variations. On the other hand, significant differences were observed in the protein contents of all samples, particularly between Arabica Sembalun and Arabica Sapit, compared to Arabica Sajang, Robusta Rempek, Robusta Genggelang, and Robusta Selelos. Robusta coffee beans appeared to have a slightly lower pH than Arabica beans. The latter exhibited consistent acidity in the range of 0.20–0.21, whereas the former showed higher acidity levels (0.23–0.25). Arabica beans had a lower caffeine content, averaging 1.09%, whereas Robusta beans exhibited an average caffeine content of 2.09%. This research provides valuable insights into the chemical composition of green coffee beans from different species and locations within Geopark Rinjani, contributing to a better understanding of the factors influencing the aroma and quality of coffee
EVALUATION OF METHODS FOR TOTAL RNA EXTRACTION FROM THE ENDOSPERM OF COCOS NUCIFERA VAR. MAKAPUNO IN VIETNAM FOR MOLECULAR ANALYSIS
Get PDFSap coconut (Cocos nucifera L. var. makapuno) in Vietnam is a mutant coconut variant; coconut water is in the state of lotus glue, and coconut rice is like cream. For high-quality transcriptome, sequencing, quality, purity and concentration of RNA are the key factors. However, coconut endosperm tissue has higher stiffness and fatness than the leaf tissue, which complicates the extraction process. Moreover, RNA is much more difficult to preserve than DNA. In this study, various RNA extraction methods were examined in Vietnamese waxy coconut endosperm tissue samples. Optimum extraction and preservation of the RNA using the simplest possible chemicals was the objective of this study. The modified CTAB method with LiCl and the TRI reagent method were tested and evaluated. The purity, concentration and quality of RNA after storage were improved. The findings indicated that the TRIsure extraction method with the addition of NaCl and β-mercaptoethanol yielded optimum RNA quality. The RNA concentration was 159 ng/µL, with a purity ratio of 1.94 ± 0.04 for A260/A280 and 1.58 ± 0.02 for A260/230. RNA samples remained stable for up to 3 weeks when stored in absolute ethanol at 8°C–10°C, which significantly reduced their degradation during transportation. This study facilitated the use of simple chemicals for high-quality RNA extraction from coconut endosperm and its preservation for applications in high throughput sequencing
CADMIUM, NICKEL, AND LEAD CONCENTRATION OF MUNICIPAL DUMPSITE IN WESTERN SAMAR, PHILIPPINES
Get PDFHeavy metal is one of the major problems due to its accumulation from the soil to the food chain, wherein dumpsites are the primary sources of heavy metal pollution. This study aimed to determine the presence of heavy metals in the soil of Santa Rita, Western Samar dumpsite and to quantify them to obtain knowledge on the possible high contamination that may affect the surrounding areas. This study focused on the presence and concentrations of heavy metals Cd, Ni, and Pb. Eighteen (18) soil samples were acquired within the three sampling sites: shoulder slope, main dumpsite, and foot slope. Each sampling site has three sampling points with a depth of 0 - 30 cm and 30 - 60 cm. Analysis showed that all heavy metals are present in the dumpsite, and the concentrations ranged from 0 - 0.1 mg/kg, 0.09 - 3.7 mg/kg, and 0.09 - 3.7 mg/kg for cadmium, lead, and nickel, respectively. In comparing heavy metals within the sampling sites and depths, only cadmium has a significant difference, while Ni and Pb have no significant difference. Compared with WHO standards, all heavy metals tested still fall within the standard limit. Therefore, the dumpsite is still at a safe level. However, residents should take measures to maintain the soil quality since heavy metal contamination in dumpsites is likely to exacerbat
YEAST PROBIOTICS WITH POTENTIAL TO ASSIMILATE CHOLESTEROL IN VITRO
Get PDF In the last two decades the use of yeasts as new probiotics has increased significantly. Therefore, our current research was focused on the investigation of yeasts for novel probiotic development in Bali. The main objectives of this research were to isolate and characterize yeasts isolated from ragi tape (dried mix cultures of microorganisms normally used in the fermentation of rice or cassava in Indonesia) and tape ketan (fermented sticky rice) for possible use as yeast-based novel probiotics, with capability to assimilate cholesterol in vitro. In this study, the potential yeast isolates were evaluated for survival at low pH conditions (pH 2, 3, or 4) and in high levels of sodium deoxicholic (NaDC), at concentrations of 0.2, 0.4, or 0.6 mM. In addition, the yeast isolates were also evaluated for their ability to assimilate cholesterol in vitro and to elucidate biotransformation of cholic acid into deoxycholic acid. This study led to 10 isolates that were resistant to pH levels of 2, 3, or 4 and to NaDC at concentration of higher than 0.4 mM. Most of those isolates were also found to assimilate cholesterol in vitro at the rate of between 18% and 76% in 24 hours incubation. In the biotransformation test, none of those isolates transformed cholic acid into deoxycholic acid, indicating that they are safe and have potential to be developed into novel probiotics, either for human or cattl
UNDERSTANDING NATURAL REGENERATION IN BURNED TROPICAL PEATLAND: A STRATEGY TO ACCELERATE THE FOREST RECOVERY PROCESS
Get PDFThe 2015 massive forest fires across Central Icalimantan left large areas of burned peatlands that need to be restored, demanding substantial resources. To understand natural regeneration of burned peatland and how planting might accelerate its recovery process, the regrowth of burned peatlands was measured with different fire frequencies. Three transects were established. Each transect consisted of five 20 x 20 m plots with 30 m intervals. All woody species were recorded and classified into three categories as new regrowth, regrowth, and remnant trees that survive from the last fire. In addition, data from fifteen 2 x 2 m permanent natural regeneration plots and evaluation on survival rate of 2017 planting were also analyzed. Research results suggested that the absence of remnant trees due to frequent or severe fires does not always impede the emergence of new recruitments, although diversity of forest regrowth is likely to be affected by its proximity to forest remnants. The floristic composition also showed a domination of pioneer species, giving evidence that forest recovery is initiated. Our study indicated that the combination of fire frequency, fire intensity, and proximity to remnant forest will produce different degrees of forest recovery, and the result will be unique for each site. It is concluded that to support the recovery process through planting activity, the successional stage of the designated sites should be determined first. The common planting method on large areas with mixed climax-high valuable trees was not beneficial unless the restoration sites had reached the later stages of succession
MONITORING FOREST AREA CHANGE USING QUICKBIRD
Get PDFA study was conducted to compare the urban forest management in three urban forests in Samarinda City. The application of GIS (Geographic Information System) is one of the alternatives to conduct a variety of processes such as: providing geographical information system, identifying the areas of urban forests in Samarinda, helping to plan the process of map digitalization and performing overlay process. The main method used for the data analysis process on the map was the overlay process data analysis technique. The research findings showed that: 1) the appointment of urban forests as the initial step of urban forest development needed more implementation from the government; 2) the urban forest determination needed more socialization to the owner of the urban forest and the public in 1992 and 2019; 3) the urban forests needed more management. There were some similarities and differences in the management of urban forests in the three study locations. The similarities among the three locations were that the three locations had already met the minimum standards of one urban forest location even though there was still one location outside of these three locations which did not meet the minimum standard. The differences were in managing the urban forests. These differences indicated that the urban forest policy was not fully implemented in Samarinda City
BIOLOGICAL CHARACTERISTIC OF INDONESIAN GAYO HORSE
Get PDFThis study aims to find out the characteristic of gayo horse and to identify the population of gayo horse. Data collection was conducted through selection process over 100 local horse distributed in Central Aceh Sub-districts, Gayo Lues and Bener Meriah. The result was 30 gayo horses with varying age distribution. Detail observation was performed on six gayo horses of male (n=3) and female (n=3). The observation consisted of morphological observation and morphometry. Data collection of gayo horse population was based on annual report from local Animal Husbandry and Fishery Official over the last 5 years. Result showed that gayo horse has straight cranial shape similar to thoroughbred with smaller size, thick and stiff mane, and ears akin to donkey. Gayo horse body height ranges between 113-120 with body weight ranging around 215-280 kg. Gayo horse is agile despite living in mountain and able to carry heavy weight. There has been drastic decline of population in year 2010-2014. In conclusion, gayo horse is included as large pony category, and without any rescue effort, gayo horse is predicted to be extinct in 2037
ROLE OF MYCORRHIZA HELPER BACTERIA ON MYCORRHIZAL COLONIZATION AND NEMATODE Pratylenchus coffeae INFECTION
Get PDFThe coffee nursery is susceptible to endoparasitic Pratylenchus coffeae. Application of biological method in the nursery is suggested to control the nematode population and maintain the seedling health. The objectives of this study were to observe the ability of Arbuscular Mycorrhiza Fungi (AMF) Glomus spp. and liquid inoculant of Mycorrhiza Helper Bacteria (MHB) consortium Pseudomonas diminuta and Bacillus subtilis for increasing AMF colonization and reducing the infection P. coffeae in Arabica coffee seedling and their growth. A pot experiment was conducted using a Completely Randomized Block Design with four treatments and five replications. The treatments were Glomus spp. spore inoculation without and with two concentrations of MHB. The control treatment did not receive Glomus spp. and MHB. The seedlings were growing in the greenhouse for three months. The results indicated that Glomus spp. and MHB consortium significantly reduced the nematode total number in soil and roots by approximately 30%; and infection degree of P. coffeae by 50%. The application of Glomus spp. significantly increased root colonization by mycorrhizal fungi, but MHB inoculation did not affect the mycorrhizal colonization. Seedlings treated with MHB had higher shoot length compared to the plant without MHB and control; but the leaves number and shoot dry weight of seedlings were not affected by all treatments. Even though the root fresh weight was reduced after MHB treatment, the lateral roots growth of MHB-treated seedling visually was improved. The experiment demonstrated that MHB was efficient to reduce P. coffeae infection of Arabica seedling