• Economic and Environmental Geology
• /
• v.6 no.1
• /
• pp.81-81
• /
• 1973

• Proceedings of the KSEEG Conference
• /
• 2001.04a
• /
• pp.249-249
• /
• 2001

• Journal of Forest and Environmental Science
• /
• v.31 no.3
• /
• pp.192-201
• /
• 2015

Information on plant diversity and community structure are required to chalk out necessary actions for conservation management. The present study assessed the composition and diversity of tree species in Kamalachari Natural Forest of Chittagong South Forest Division, Bangladesh, during April 2010 to November 2011. A total of 107 tree species belonging to 72 genera and 37 families were recorded, where Moraceae family was represented by maximum (11) species. Density, Basal area and volume of tree species were $418{\pm}20.09stem/ha$, $21.10{\pm}2.62m^2/ha$ and $417.4{\pm}79.8m^3/ha$ respectively. Diameter and height class distribution of tree species revealed an almost reverse J-shaped curve. Both the number of species and percentage of tree individuals were maximum in the lower DBH and height ranges. Anthropogenic disturbances like illegal tree cutting, over extraction, settlement inside forest area etc. were noticed during the study, which are supposed to cause gradual decrease of both tree species and individuals in the higher DBH and height classes. However, Artocarpus chama was found dominant showing maximum IVI followed by Schima wallichii, Aporosa wallichii, and Lithocarpus acuminata. The quantitative structure of the tree species of Kamalachari natural forest is comparable to other tree species rich tropical natural forests. The findings of the study may help in monitoring future plant population changes of the identified species and adopting species specific conservation programs in Kamalachari natural forest.

• Journal of Environmental Science International
• /
• v.12 no.2
• /
• pp.217-225
• /
• 2003

Samples of size-fractionated PM10 (airborne particulate matter with aerodynamic diameter less than $10\mu\textrm{m}$) were collected at an urban site in Jeju city from May to September 2002. The mass concentration and chemical composition of the samples were measured. The data sets were then applied to the CMB receptor model to estimate the source contribution of PM10 in Jeju area. The average PM10 mass concentration was 28.80$\mu\textrm{g}/m^3$ ($24.6~33.49\mu\textrm{g}/m^3$), and the FP (fine particle with aerodynamic diameter less than $2.l\mu\textrm{m}$ fraction in PM10 was approximately 8% higher than the CP (coarse particle with aerodynamic diameter greater than $2.l\mu\textrm{m}$ and less than $10\mu\textrm{m}$ fraction in PM10. The CP composition was obviously different from the FP composition, that is, the most abundant water soluble species was nitrate ion in the FP, but sulfate ion in the CP. Also sulfur was the most dominant element in the FP, however, sodium was that in the CP. From CMB receptor model results, it was found that road dust was the largest contributor to the CP mass concentration (45% of the CP) and ammonium nitrate, domestic boiler, and marine aerosol were major sources to the CP mass. However, the secondary aerosol was the most significant contributor to the FP mass concentration (45% of the FP). In this study, it was suggested that the contributions of soil dust and gasoline vehicle became very low due to collinearity with road dust and diesel vehicle, respectively.

• Environmental Engineering Research
• /
• v.15 no.2
• /
• pp.93-98
• /
• 2010

This study aims to determine the chemical composition and seasonal variation of atmospheric acid deposition in order to identify possible sources contributing to precipitation. Sampling and analysis of 132 wet deposition samples were carried out from January to December 2008 at Mae Hia Research Center, Chiang Mai University, Chiang Mai Province. Total precipitation was 1,286.7 mm. Mean electro-conductivity and pH values were 0.94 mS/m and 6.27, respectively. Major cations ($Na^+$, ${NH_4}^+$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$) and major anions ($HCOO^-$, $CH_3COO^-$, $Cl^-$, ${NO_3}^-$, and ${SO_4}^{2-}$) were determined by Ion Chromatography. The relative volume weight mean concentrations of anions, in descending order, were ${SO_4}^{2-}$ > ${NO_3}^-$ > $Cl^-$ > $CH_3COO^-$ > $HCOO^-$ and those of cations were $NH_4^+$ > $Ca^{2+}$ > $Mg^{2+}$ > $K^{+}$ > $Na^+$. Results of a principle component analysis highlighted the influence of various possible sources of ions such as agricultural activity, fuel combustion, marine sources, soil resuspension, and biomass burning.

• Journal of Forest and Environmental Science
• /
• v.35 no.3
• /
• pp.189-196
• /
• 2019

Plants are consumed by a myriad of organisms that compete for resources. Direct interactions among multiple plant-feeding organisms in a single host can range for each species from positive to negative. Wood-boring beetle faces a number of biotic and abiotic constraints that interfere with the good prospects from the tree. Biotic factors, including arthropod pests and diseases, and abiotic factors, such as drought and water-logging, are the major constraints affecting the species. The present study aimed to provide basic data for analyzing forest health, identify the kinds of wood-boring beetles in the central part of Korea. Our second goal was to analyze the species composition and diversity of regional communities and to examine. A total of 10,461 individual wood-boring beetles belonging to 8 families and 50 species attracted to trap trees in the pine forests were recorded during the study period on study sites. The results of the analysis of collected species showed that the community structure on all study sites was similar. Seasonal occurrences of dominant wood-boring beetles (5 species) from each study site showed the highest number of all species, except for Siphalinus gigas in May, followed by a gradual decline, and the largest number of Siphalinus gigas appeared in June. The similarity index of species composition was relatively high, ranging from 0.75 to 0.90 for each study site.

• Environmental Mutagens and Carcinogens
• /
• v.15 no.2
• /
• pp.140-147
• /
• 1995

For studying the effect of different dietary fats on carcinogenesis, fatty acid composition of membrane and lipid peroxidation were measured. Male Sprague-Dawley rats were fed on diet containing 15%(w/w) beef tallow or soybean oil. A single dose of 50 mg 2-AAF/kg B.W. was injected i.p. in each diet group 10 times. Rats were sacrifled after 1, 5, 10, and 15 weeks from the first injection. By 2-AAF injection, !ipid peroxidation increased slightly compared to control group. The rats fed on different fats had similar MDA production and those fed on soybean oil had slightly higher free radical concentration measured by ESR. In young rats, iipid peroxidation level was high and hydroxy radical production was higher in soybean oil group than in beef tallow group. With age, the lipid peroxidation values were decreased initially then increased. The fatty acid composition in microsomal membrane was reflected by dietary fatty acid composition. In soybean oil group, monoenoic acid was lower and polyunsaturated fatty acid was higher than beef tallow group. Linoleic acid contents showed the most discrepancy among groups. By 2-AAF treatment, iinoleic acid content and unsaturation index increased in soybean oil group. But in beef tallow group, there was no difference in fatty acid contents.

• Economic and Environmental Geology
• /
• v.13 no.1
• /
• pp.21-27
• /
• 1980

${\delta}^{13}C$ and ${\delta}^{18}O$ values were determined for the Paleozoic limestones (Great Linestone Series) from the Taebaegsan region and the age-unknown limestones (Janggun Formation) from the Janggun mine, Korea. Limestones of the Great Limestone Series exhibit a range of carbon isotopic composition from -4.5 +1.3‰ with a mean ${\delta}^{13}C$ value of -1.1‰, relative to the PDB standard, and of oxygen isotpic composition from +8.8 to +23.3‰ with a mean ${\delta}^{18}O$ value of +16.0‰, relative to the SMOW, falling into the normal marine limestone range according to Keith and Weber (1964), and Degens and Epstein(1964). Carbon isotopic composition of limestones of the Great Limestone Series becomes progressively lighter from Pungchon limestone of middle Cambrian age to mid-Ordovician Maggol limestone, possibly due to change in depositional environment in the Taebaegsan basin. Variation in isotopic composition of limestones from Hwajeol to Dumugal formation offers the possibility or deposition in shallow sea environment, in which fresh waters were added in several stages. Janggun limestone of unknown age may be corelated with the Paleozoic limestones of Great Limestone Series as infered from the istopic composition ranging from -2.8 to + 0.7‰ of ${\delta}^{13}C$ and +13.4 to +22.4‰ of ${\delta}^{18}O$.

• Journal of Environmental Science International
• /
• v.30 no.7
• /
• pp.537-545
• /
• 2021

This study aimed to investigate the improvement effect of 5% (w/w) mung bean (Phaseolus aureus L.) on lipid composition and protein concentration in hyperlipidemic rats. Seven-week-old male (Sprague-Dawley) rats were divided into four groups (n=6, each), and fed experimental diets containing mung bean meal [basal diet+5% (w/w) mung bean (BM), basal-hyperlipidemic diet+5% (w/w) mung bean (BHM)], basal-hyperlipidemic diet (BH), and control (basal diet, BD). Lipid composition in the mung bean diet groups (BM and BHM) evidenced significant reductions in serum total cholesterol, low-density lipoprotein cholesterol, atherosclerotic index, cardiac risk factor, triglyceride, phospholipid, free cholesterol, cholesteryl ester, blood glucose, nonesterified fatty acid, and an elevation in high-density lipoprotein cholesterol. The serum albumin/globulin ratio was increased in mung bean diet-supplemented rats compared to that in hyperlipidemic rats (p < 0.05). Total calcium, phosphorus and potassium concentrations in sera were higher in the BM, BHM and BD groups than in the BH group. Concentrations of sodium and chlorine in sera were lower in the mung bean diet-supplemented groups than in the hyperlipidemic group. The in vivo experiments showed that ingestion of mung bean was effective in improving lipid composition, protein concentration, and blood glucose.

• Korean Journal of Agricultural Science
• /
• v.42 no.3
• /
• pp.191-199
• /
• 2015

We conducted this research to observe the changes of surface morphology and composition of clay minerals influenced by various concentrations of fluoric acid. Hydrofluoric acid (HA), a solution of hydrogen fluoride (HF) in water, is a colourless solution that is highly corrosive, capable of dissolving many materials, especially oxides. To do this, we treated several concentrations of HA on the ground soil samples collected from the agricultural experimental station located at Chungnam National University to observe the influence of fluoric acid on the changes of surface structures and elemental composition of clay particles. Generally, microscopic examination showed that the HA can not only attack an edge of clay particles but also start at any point where structural defects and weaknesses predisposed sites to acid. The orderly flake arrangement of clay minerals may reflect certain crystal symmetry elements. The ESEM-EDS results of element composition of clay particles influenced by HA indicated the changes of structures of clay minerals. It is also clear from the formation of etch figures and element composition of clay particles that the product layer at least partially dissolved or disintegrated in the presence of acid. Conclusively, the clay structures can be strongly influenced by concentrations of HA, resulting in changes of physical and chemical properties that can determine the behavior of solute transport as well as mobility of ions in soils.