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- Use of Hot Spot Analysis to Detect Underground Coal Fires from Landsat-8
TIRS Data: A Case Study in the Khanh Hoa Coal Field, North-East of Vietnam
Authors: Thanh Tien Nguyen, Tuyen Danh Vu
Pages: 1 - 10; DOI: 1
Abstract: Underground coal fire (UCF) detection from remotely sensed data plays an important role in controlling and preventing the effects of coal fires and their environmental impact. The limitation of commonly used methods does not take into account spatial autocorrelation among observations. For solving this limitation, a method for UCF detection was proposed using hot spot analysis (HSA). Based on the radiative transfer equation (RTE), land surface temperatures (LSTs) were firstly retrieved from the Landsat-8 TIRS data. The degree of spatial clustering among these LSTs was measured using HSA. UCF areas were then delineated based on 99 percent confidence level of hot spot areas. These fires were finally validated using known UCF sites and cross-validated with the results extracted from the ASTER TIR image. It was found from a case study in the Khanh Hoa coal field (North-East of Vietnam); (i) UCFs were strongly correlated with known coal fires and were highly consistent with those obtained from the ASTER TIR data; (ii) a total fire area of 197 hectares was detected, of which the fire areas of low, medium, high and extremely high levels were 37.3, 47.3, 53.2 and 59.3 hectares respectively; (iii) these fires were mainly detected in the central area and at coal ash dump sites of the southern coal field. The results show HSA can be used to effectively detect UCFs.
PubDate: 2019-02-21
Issue No: Vol. 17, No. 3 (2019)
- Assessment of Surrogate of Ecosystem Health Using Indicator Species and
Mixed-Species Bird Flock
Authors: Nurul L. Winarni, Nuruliawati Nuruliawati, Zahrah Afifah
Pages: 11 - 18; DOI: 1
Abstract: Investigation of the use of indicator species as a surrogate for ecosystem health was conducted during 2014 in the periphery of the Bukit Barisan Selatan National Park, Lampung, Indonesia. The survey area composed of forest, edge, and agricultural areas in three sites at the Pemerihan village. We used point count for bird surveys within 1 km transect to obtain the data and ad-libitum observation for mixed-species bird flock. The analysis was made by using Indicator Value (IV) to select the potential indicator species which complemented how mixed-flock groups formed at the sites and further analyzed by using principal component analysis. Among 127 species recorded, one species has been identified with high IV (IV>60) and 15 species have intermediate IV (30<IV<60). Our results suggested that Sooty-headed Bulbuls Pycnonotus aurigaster are the species with the highest IV which are exploiter species and indicator for agricultural gardens. Moreover, none of the birds with highest IV overlap among habitats, which indicate that proportions are very specific in terms of habitat types. Based on principal component analysis, mixed-flocks tend to comprise of edge-to-forest species and formed at edge which may indicate food availability in the area.
PubDate: 2019-03-18
Issue No: Vol. 17, No. 3 (2019)
- A Computational Program for Estimating Atmospheric Corrosion of Monuments
Authors: Rattapon Onchang, Darryl W Hawker
Pages: 19 - 28; DOI: 1
Abstract: This study developed a novel computer program for predicting the deterioration of various types of materials from historic monuments caused by exposure to atmospheric pollution. The program was designed based on a set of materials’ dose-response functions, which take air pollutants together with climatic parameters into account. It is a web-based application that requires three input datasets: monuments’ material characteristics, local meteorological data and air pollution levels over a defined exposure time. It is also capable of estimating restoration costs. Quantification of future monument deterioration is possible by extrapolation of linear temporal relationships for air pollution and meteorological parameters. This user-friendly-interface program cooperates with Google Maps™ to find the nearest air pollution and meteorological stations to the monument site. The program may be used as a tool providing quantitative information for effective policy-making in conservation of cultural heritage monuments. To illustrate its use, the program was employed to assess the accumulated deterioration of 75 Buddhist monuments comprised of various materials located in a historical area of Bangkok, Thailand. It was estimated that the total accumulated material loss from all monuments over seven years exposure in this environment to be approximately 410 cm3 with an overall restoration cost of about 210,000 USD.
PubDate: 2019-04-29
Issue No: Vol. 17, No. 3 (2019)
- Assessment of Watershed Carrying Capacity for the Aesesa Flores Watershed
Management, East Nusa Tenggara Province of Indonesia
Authors: Nicolaus Noywuli, Asep Sapei, Nora H. Pandjaitan, Eriyatno Eriyatno
Pages: 29 - 39; DOI: 1
Abstract: The Aesesa Flores (AF) watershed has an important role for the community in the district of Ngada and Nagekeo, East Nusa Tenggara Province of Indonesia. However, in recent years, over exploitation of natural resources in the AF watershed has caused severe land degradation in the region. This study analyzed the carrying capacity of the AF watershed. The assessment of the AF watershed carrying capacity in this study was done according to the Indonesian Ministry of Forestry Regulation Number P.61/2014 that regulates the monitoring and evaluation of watershed management. The main objectives of this study were to assess the carrying capacity of the AF watershed, and evaluate the suitability of the aforementioned regulation to its condition. The results of carrying capacity analysis showed that the upstream region of the AF watershed was categorized to have a low carrying capacity condition, while both the middle and downstream region of the watershed were categorized to have a moderate carrying capacity condition. These results indicated that there was a need to prioritize the rehabilitation and land management in the upstream region of the AF watershed, in order to improve its condition.
PubDate: 2019-05-01
Issue No: Vol. 17, No. 3 (2019)
- Species Composition and Spatial Distribution of Dominant Trees in the
Forest Ecotone of a Mountain Ecosystem, Northern Thailand
Authors: Dokrak Marod, Sutheera Hermhuk, Sarawood Sungkaew, Sathid Thinkampheang, Torlarp Kamyo, Wimonmart Nuipakdee
Pages: 40 - 49; DOI: 1
Abstract: Plants’ ecological niches are important to study, particularly for applying the knowledge to restoration programs. This study clarified the relationships of tree species composition and spatial distribution to environmental factors in a mountain ecosystem. A 3 ha permanent plot was established across the forest ecotone at Doi Suthep-Pui National Park, Chiang Mai Province, Thailand. The spatial distributions of the 20 dominant tree species were analyzed using a generalized linear model (GLM) combined with geographic information system (GIS) techniques. High species diversity was found, including 165 species representing 118 genera and 59 families. Elevation strongly influenced tree distribution, which could be divided into three groups: low-altitude species in deciduous dipterocarp forest (DDF), high-altitude species in lower montane forest (LMF) and coexisting DDF and LMF species. The GLM analysis revealed that soil texture, which ranged from sandy to clayey, influenced tree distribution. The results suggest that restoration programs should select suitable species based on their niches.
PubDate: 2019-03-19
Issue No: Vol. 17, No. 3 (2019)
- Seasonal Variation in Sexual Size Dimorphism in the Wrinkle-lipped
Free-tailed Bat (Chaerephon plicatus Buchannan, 1800) Population in the
Khao Chong Phran Non-hunting Area, Thailand
Authors: Nutthakarn Boonpha, Prateep Duengkae, Supaporn Wacharapluesadee, Chumphon Kaewket
Pages: 50 - 57; DOI: 1
Abstract: The Khao Chong Phran Non-hunting Area has the largest population of wrinkle-lipped free-tailed bats (Chaerephon plicatus) in Thailand. We examined monthly variations in sexual size dimorphism through measurements of forearm length and body mass during 2016. Bats were captured in each month at dawn and dusk. Individuals were sexed, aged, measured and marked before release. During the year, we caught 1,715 individuals. Of these, we used only adult, non-pregnant individuals (405 males and 538 females) for our analysis. Males had significantly larger forearm lengths and body masses than females. The body masses of both sexes peaked at the beginning and end of the rainy season, and bats captured at dawn were heavier than those netted at dusk. Seasonal fluctuations in body mass were correlated with monthly variation in rainfall; the positive correlation is likely explained by the greater insect abundance during wet months. The climate in western Thailand is expected to become warmer and drier, with likely negative effects on populations of this species due to reductions in insect food resources. Maintenance of this large population of C. plicatus in the study area will depend on concerted conservation efforts and further research focused on population dynamics, prey availability and foraging habitats.
PubDate: 2019-04-04
Issue No: Vol. 17, No. 3 (2019)
- Use of Agricultural Residues to Remove Iron from Groundwater in Modified
Airlift Aerator
Authors: Thanakrit Neamhom
Pages: 58 - 67; DOI: 1
Abstract: This work investigated groundwater iron adsorption capacity from rice husk, rice straw, water hyacinth and coconut shell, agricultural residues commonly found in Thailand. This study also investigated the adsorption behavior using an appropriate isotherm model in the batch process. The process was conducted using a modified airlift tray aerator. The use of a single adsorbent plate in a modified aerator obtained a removal capacity in the range of 0.3 to 0.9 mg/L, but the final iron concentration in the sample was above the regulatory standard. To increase the efficiency using the equivalent condition, the multiple adsorbent plate system was tested. The application of four rice husk plates achieved the allowance value and resulted in a final iron concentration of 0.28 mg/L. Based on the results, iron was reduced by increasing the number of adsorbent plates. Hence, rice husk can be sustainably used to adsorb iron in groundwater. At equilibrium, the adsorption isotherm was fitted to the Freundlich equation with an R2 value of 0.9805. This implied that the adsorption sites on the rice husk surface are heterogeneous in nature and presented a strong interaction between iron and rice husk. They revealed a maximum adsorption capacity of 0.73 mg/g. Moreover, this practice also decreased the amount of total hardness which could help alleviate nuisance and public health problems.
PubDate: 2019-04-04
Issue No: Vol. 17, No. 3 (2019)
- Acid-Catalyzed Esterification Pretreatment of High Free Fatty Acid Crude
Rice Bran Oil for Biodiesel Production
Authors: Tin Mar Lar Thein, Vinod K. Jindal, Ranjna Jindal, Nuttawan Yoswathana
Pages: 68 - 79; DOI: 1
Abstract: This study investigated the acid-catalyzed esterification of two brands of crude rice bran oil (CRBO) with free fatty acids (FFAs) content of about 8 and 10%, respectively. Experimental variables included reaction time, methanol-to-FFA molar ratio and sulfuric acid content with temperature and stirring speed fixed at 60 °C and 600 RPM, respectively. A central composite design was used initially for sequential experimentation and followed by a Box-Behnken design to refine the optimum process conditions. Results showed that final FFA in CRBO could be reduced to less than 1% FFA in a single-step. The methanol-to-FFA molar ratio had the maximum influence on the esterification process and was followed by the reaction time and amount of catalyst. The optimum conditions for FFA conversion in CRBO were: reaction time 90 and 48 min, 62:1 and 70:1 methanol-to-FFA molar ratio, 22.5 and 20% (w/w) sulfuric acid based on FFA for Brand I and II, respectively. Under these pretreatment conditions, initial FFA was reduced to 0.61 and 0.70%, respectively making the CRBO suitable for biodiesel production.
PubDate: 2019-04-23
Issue No: Vol. 17, No. 3 (2019)
- Growth Response of Dipterocarpus tuberculatus and Shorea roxburghii
Seedlings to Astraeus odoratus
Authors: Tharnrat Kaewgrajang, Baramee Sakolrak, Uthaiwan Sangwanit
Pages: 80 - 88; DOI: 1
Abstract: In this study, we investigated the effects of the highly prized ectomycorrhizal (ECM) mushroom, Astraeus odoratus, on the growth of Dipterocarpus tuberculatus Roxb. and Shorea roxburghii G. Don seedlings. The two seedling species were inoculated using two methods: 1) spore suspension of 25 mL/seedling; and 2) hyphal suspension of 25 mL/seedling. On harvesting, it was found that 30-60% of the roots formed by the inoculated seedlings were ectomycorrhizal roots. Seedling development was influenced by the inoculation method and the host plant species. A higher growth response was observed in the S. roxburghii seedlings inoculated with A. odoratus compared to D. tuberculatus seedlings. Moreover, the non-inoculated S. roxburghii seedlings had a lower growth response than D. tuberculatus seedlings, but their growth response was significantly higher than D. tuberculatus seedlings inoculated with a spore or hyphal suspension of A. odoratus. However, there was no difference between the effects of the spore and hyphal suspension treatments. Therefore, both the inoculation methods can be used to enhance the growth of seedlings, especially that of S. roxburghii.
PubDate: 2019-05-08
Issue No: Vol. 17, No. 3 (2019)
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