• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.260-269
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• 2009

Hwabuk Dam has been under construction to reduce flood damage in Nakdong River watershed and to supply stable water for middle area of Gyeongbuk Province. Therefore, fish investigation in up and downstream of the dam was conducted from 2004 to 2008 in order to determine any negative effect on fish community due to dam construction and to use as fundamental data for conserving species diversity and maintaining stream health. According to data analysis on water quality, temperature, dissolved oxygen, pH, suspended solids, and total E-coli had seasonal variation, but they did not significantly differ in sites. However, biological and chemical oxygen demand, chlorophyll-a, nitrogen, and phosphorus representing organic matter and nutrient concentration were higher in upper site and decreased to lower site so that they differed by site. Concentration of arsenic among the heavy metals was less than 0.05 mg $L^{-1}$, which is regulated for protection of human health in water quality standard, except for 0.092 mg $L^{-1}$ in June 2005. During the study period, the total number of fish caught from the 6 sites was 10,263 representing 7 families 19 species. Among them, dominant and subdominant species were Korean chub (Zacco koreanus, 62.5%) and Chinese minnow (Rhynchocypris oxycephalus, 10.6%) which inhabit mostly in mid and upper streams, Korea. Among the 19 species, Korean endemic species were 9 species (47.4%) including Korean slender gudgeon (Squalidus gracilis majimae), Korean dark sleeper (Odontobutis platycephala), and Korean shiner (Coreoleuciscus splendidus). There was several individuals of the $1^{st}$-class endangered species, Naktong nose loach (Koreocobitis nahtongensis), caught in 2005${\sim}$2007, and no introduced species of fish was found in entire sampling period. According to result of community analysis, dominance index decreased toward lower site, but diversity and richness indices increased toward lower site. The equation of length-weight relationship on the dominant species was TW=0.000003$(TL)^{3.2603}$. The parameter b in the equation was greater than 3.0 indicating good nutritional condition in the populations. Compared to populations of Korean chub in other streams, the population in Hwabuk Dam watershed had higher mean of condition factor by size indicating better growth rate. With fish fauna and multi-metric health assessment model in each sampling attempt, index of biotic integrity (IBI) was evaluated and it resulted mostly in good (26${\sim}$35) and excellent (36${\sim}$40) condition in all sites, and the mean of IBI was the highest in site 5. The results indicate that it is very important to study not only environmental impact assessment with fish composition but also stream health assessment in order to conserve healthy aquatic ecosystem.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.3279-3285
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• 2014

This study aimed to understand seasonal and geographical characteristic of chlorophyll-${\alpha}$ (chl-${\alpha}$), COD (chemical oxygen demand) and Escherichia coli at Gwangyang Bay during the period from February 2010 to November 2012. The bay is divided into three different zones based on the pollutant levels and geographical characteristics. During the study periods, water temperature, salinity, Chl. ${\alpha}$, and chemical oxygen demand (COD) varied in the range of $4.68-28.63^{\circ}C$, 1.94-33.84 psu, 0.31-35.10 ${\mu}gL^{-1}$, and 0.70-13.35 $mgL^{-1}$, respectively. Total chl-a concentration were high at the zone I, which can be characterized as a semi-enclosed eutrophic area, and it were low at the zone III, which is influenced by low nutrients of surface warm water current from offshore of the bay. The high concentration of COD was observed at inner bay during the four seasons and the water quality level was kept to be bad condition during spring season at the zone II, which is influenced by Seomjin River water. The highest colony form of E. coli was recorded to be 3550 $cfuL^{-1}$ during summer at station 1 (zone I), whereas it was relatively kept low level during all seasons at the zone III. As a result, the E. coli was correlated with water temperature (r=0.31 p<0.05) and salinity (r=-0.55 p<0.05), implying that those parameters have play an important crucial role in proliferation of E. coli. Consequently, our results indicated that the E. coli can be significantly promoted within pollutant sources including the high nutrients supplied by rive discharge during spring and summer rainy seasons in semi-enclosed area of Gwangyang Bay.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.90-104
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• 2001

This study is aimed to analyze and to evaluate the revegetation and soil conservation technology in desertification-affected sandy land, resulting from the project of "Studies on the desertification combating and sand industry development". Main native plants for combating desertification : The general characteristics of vegetation distribution in desertified regions are partially concentrated vegetation distribution types including the a) desert plants in low zone of desert or sanddune of depressed basin, b) salt-resistant plants around saline lakes, c) grouped vegetation with Poplar and Chinese Tamarix of freshwater-lakes, saline-lakes and river-banks, d) gobi vegetation of gravel desert and e) grassland and oasis-woods around the alluvial fan of rivers, etc. Generally, Tamarix ehinensis Lour., Haloxylon ammodendron Bunge., Calligonum spp., Populus euphratica Oliver., Elaeagnus angustifolia L., Ulmus pumila L., Salix spp., Hedysarum spp., Caragana spp., Xanthoceras sorbifolia Bunge., Nitraria tangutorum Bobr., Lespedeza bicolor, Alhagi sparsifolia Shap., Capparis spinosa L., Artemisia arenaria DC., etc. are widely distributed in desertified regions. It is necessary for conducting research in the native plants in desertified regions. Analysis of intensive revegetation technology system for combating desertification : In the wind erosion region, the experimental research projects of rational farming systems (regional planning, shelterbelts system, protection system of oasis, establishment of irrigation-channel networks and management technology of enormous farmlands, etc.), rational utilization technology of plant resources (fuelwood, medicinal plants, grazing and grassland management, etc.), utilization technology of water resources (management and planning of watershed, construction of channel and technology of water saving and irrigation, etc.), establishment of sheltetbelts, control of population increase and increased production technology of agricultural forest, fuelwood and feed, etc. are preponderantly being promoted. And in water erosion region, the experimental research projects of development of rational utilization technology of land and vegetation, engineering technology and protection technology of crops, etc. are being promoted in priority. And also, the experimental researches on the methods of utilization of water (irrigation, drainage, washing and rice cultivation, etc.), agricultural methods (reclamation of land, agronomy, fertilization, seeding, crop rotation, mixed-cultivation and soil dressing works, etc.) and biological methods (cultivation of salt-resistant crops and green manure and tree plantation, etc.) for improvement of saline soil and alkaline soil in desertified-lands are actively being promoted. And the international cooperations on the revegetation technology development projects of desertified-lands are sincerely being required.

• Journal of Korean Historical Folklife
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• no.34
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• pp.253-281
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• 2010

This study has its purpose on figuring it out to the religious notion in Vietnam with the material of the divinity construction of Den Hang Pho in Sapa where is the northern region of Vietnam. To make this, the study divides the type of Vietnamese temples into four parts; Chua, Den, Dinh, and Mieu. Among them, the study pays attention to 'Den' because Vietnamese historical heroes are seated as divinity. This reason makes a reasonable case to this study to figure out a typically and generally religious faith. First of all, the study analyzes immaculate divinity, which generally consists of three and four layered system. The study confirms that the immaculate divinity started from the goddess and then extended to the concept to dominate the sky, the ground, the sea(river), and the mountain(forest). General Tran Hung Dao is the best historical hero in Vietnam and has been placed in temples called Den. The study exams the context that the divinity extended to the religious beliefs, for examples, the belief related in a childbirth by lots of narrations and ceremonies and the belief to treat a sickness, and also exams the context that the divinity placed in a divinity to make a symmetrical relation with immaculate faith. The study exams the divinity construction of Den Hang Pho as its authentic case. In this case, the study could verify a case emphasized by mountain Holy Mother among immaculate faiths. Especially, the study can confirm that General Tran Hung Dao was apotheosized as a concept to be symmetrized with immaculate divinity, and futhermore, a couple of snakes was emphasized by their positioning to every room. Tri-system lays stress on the aboriginality(locality) centered on minority races in the northern Vietnam, the national identity of Vietnam, and the ecological condition of rivers flowing the valley of high and steep peak. The confirmed facts could be said to a construction what the religious notion of tri-system makes. The study makes a conclusion that this kind of conversion-oriented religious notion naturally corresponded with region, nation, and ecologically environmental condition, and extended to the Vietnamese faith with polytheistic divinity.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.33-41
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• 2001

Enormous volumes of mining wastes from the abandoned and closed mines are disposed without a proper treatment in the upper Okdong River basin at Southeastern part of Kangwon Province. Erosion of these wastes contaminates soil, surface water, and sediments with heavy metals. Objectives of this research were to fractionate heavy metals in the mine tailing stored in the Sangdong Tungsten tailing dams and to assess the potential pollution index of each metal fraction. Tailing samples were collected from tailing dams at different depth and analyzed for physical and chemical properties. pH of tailings ranged from 7.3 to 7.9. Contents of total N and organic matter were in the ranges of 3.2~5.5%, and 1.3~9.1%, respectively. Heavy metals in the tailings were higher in the newly constructed tailing dam than those in the old dam. Total concentrations of metals in the tailings were in the orders of Zn > Cu > Pb > Ni > Cd, exceeded the corrective action level of the Soil Environment Conservation Law and higher than the natural abundance levels reported from uncontaminated soils. Relative distribution of heavy metal fractions was residual > organic > reducible > carbonate > adsorbed, reversing the degree of metal bioavailability. Mobile fractions of metals were relatively small compared to the total concentrations. Distribution of metals in the tailing dam profiles was metal specific. Concentrations of Cu at the surface of tailing dams were higher than those at the bottom. Pollution index (PI) values of each fraction of metals were ranged from 4.27 to 8.51 based on total concentrations. PI values of mobile fractions were lower than those of immobile fractions. Results on metal fractions and PI values of the tailing samples indicate that tailing samples were contaminated with heavy metals and had potential to cause a detrimental effects on soil and water environment in the lower part of the stream. A prompt countermeasure to prevent surface of tailings in the dams from water and wind erosions is urgently needed.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.3
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• pp.163-179
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• 2003

Multifunctionality of agriculture which is not traded on the market now has been an important international issue in that it environmental and public benefits. We carried out to modify and to update the function of upland farming on flood prevention and fostering water resources. Economic values of environmental benefits were evaluated by replacement cost methods. Models to evaluate the function of preventing flood were selected as: (1)precipitation(flood-inducing) - runoff(A), (2) soil depth ${\times}$ soil air phase, (3) precipitation (flood-inducing) - runoff(B), (4) soil depth ${\times}$ effective porosity of soil. Models to estimate the function of fostering water resources were (1) saturated hydraulic conductivity (Ks) ${\times}$ duration of saturation(days) ${\times}$ (1-ratio of water flow directly into river), (2) precipitation ${\times}$ ratio of water fostered by rain resources ${\times}$ (area of upland/total land area), and (3) soil water retention quantity(under standing crop or tree) - SWRQ(in bare soil). Function of preventing flood was $883Mg\;ha^{-1}$ of water per year and 645 million Mg for the whole upland area. Function of fostering water resources was $94.1Mg\;ha^{-1}$ of water per year and 69 million Mg for the whole upland area. The value of flood-preventing function evaluated by replacement cost methods was estimated 1,428 billion won per year as compared to the cost for dam construction. The value of water resource fostering were estimated 8.6 billion won in the price of living water.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.794-800
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• 2011

To develop biochar for soil conditioner using water plants, characteristics of nutrients release of biochars were investigated under different water plants, manufacturing times and manufacturing temperatures. Under different water plants for manufacturing biochar, the concentrations of T-N and $P_2O_5$ in the water with biochars were higher in the order of CRXDM > ZIZLA > PHRCO > TYHOR > MISSA. The concentrations of $K_2O$ in the water were in the order of TYHOR ${\fallingdotseq}$ CRXDM > ZIZLA > PHRCO > MISSA. Under different manufacturing times for biochar, the concentrations of T-N, $P_2O_5$ and $K_2O$ in the water with biochars were higher in the order of 2 hr > 30 min ${\fallingdotseq}$ 1 hr. The concentrations of T-N, $P_2O_5$ and $K_2O$ in the water with biochars were on the order of $350^{\circ}C$ > $500^{\circ}C$ > $600^{\circ}C$ under different manufacturing temperatures. Total amounts of T-N and $K_2O$ releases in the water with biochars were higher in the order of CRXDM > ZIZLA > PHRCO > TYHOR > MISSA. Using biochars by water plants, total amounts of $P_2O_5$ releases in the water with biochars were on the order of CRXDM > ZIZLA > MISSA >PHRCO > TYHOR. The results of this study suggest that biochars by water plants can supply some of the nutrient requirements of crops and can be a valuable fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.330-335
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• 2009

This study was conducted to reclassify Jangho series based on the second edition of Soil Taxonomy : A Basic System of Soil Classification for Making and Interpreting Soil Surveys. Morphological properties of typifying pedon of Jangho series were investigated and physico-chemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon of Jangho series has very dark grayish brown (10YR 3/2) gravelly silt loam A horizon (0~14 cm), very dark brown (7.5YR 3/2) silty clay BAt horizon (14~31 cm), dark brown (7.5YR 3/4) silty clay Bt1 horizon (31~58 cm), brown (7.5YR 4/4) silty clay Bt2 horizon (58~90 cm), and brown (7.5YR 4/4) clay Bt3 (90~120 cm) horizon. That is developed on river terraces. The typifying pedon has an argillic horizon from a depth of 14 to more than 120 cm and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol. The typifying pedon has 0.9 % or more organic carbon in the upper 15 cm of the argillic horizon, and can be classified as Humult, which is reported for the first time in Korea. That does not have fragipan, kandic horizon, sombric horizon, plinthite, etc. in the given depths, and keys out as Haplohumult. Also that meets the requirements of Typic Haplohumult. That has 35 % or more clay at the particle-size control section, and has mesic soil temperature regime. Jangho series can be classified as fine, mixed, mesic family of Typic Haplohumults, not as fine silty over clayey, mixed, mesic family of Mollic Hapludalfs.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.133-139
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• 2012

The Aims of this study are to investigate ecological environments and indoor-rearing conditions of Eurema hecabe for artificial rearing. Two different nesting site, a open area nearby small river(A area; Daejin-ri, Gonyang-myeon, Sachun-si, Gyoungsangnam-do) and a foot of a hill area(B area; Noryang-ri, Seolcheon-myeon, Namhae-gun, Kyoungsangnam-do), selected for investigation of ecological habitat environment, and investigated two times per month, during six month, from June to November in 2010. In result, the number of butterflies, Eurema hecabe, at the hill area(B area) was 6 times more than the open area(A area). We observed the number of eggs, larvae and puapae in the B area more times compared to those in the A area. In the B area, Lespedeza cuneata was higher preference than the other host plant, Lespedeza pilosa and Albizia julibrissin. For development of indoor-rearing conditions, common grass yellow butterfly, Eurema hecabe, was reared in a room condition. As a result of oviposition preference experiment, 100-mated-female laid significantly higher number of eggs $104.9{\pm}19.6$ on Lespedeza cuneata plant, whereas the number of eggs was $12.7{\pm}4.5$ on Cassia obtusifolia plant. Moreover, the eggs hatched within $5.1{\pm}0.9$ days from the day of oviposition and procent of egg hatchability was 53.7% on host plant. The headwidth of each developmental larval stage were $0.36{\pm}0.02$(1st), $0.61{\pm}0.02$(2nd), $0.93{\pm}0.05$(3rd), $1.46{\pm}0.08$(4th), $2.25{\pm}0.11$(5th). The larval period was $12.1{\pm}0.9$ days under high temperature, long day condition($25^{\circ}C$, 16L : 8D), showing 81.0% pupal ratio. The pupal period was $6.9{\pm}0.7$ days, and the emergence rate was 79.6%. Based on above experiment, artificial rearing system of common grass yellow butterfly, Eurema hecabe was completed in indoor condition.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.18-24
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• 2007

Paddy fields are apparently nonpoint source pollution and influence water environment. In order to improve water quality in rivers or lakes, to low nutrient load from paddy fields are required. To establish comprehensive plan to control agricultural non-point source pollution, it is imperative to get a quantitative evaluation on pollutants and pollution load from paddy fields. A field monitoring study was carried out to investigate the water balance and losses of nutrients from fields in Sumjin river basin. The size of paddy fields was 115 ha and the fields were irrigated from a pumping station. The observed total nitrogen loads from paddy fields were larger than those of the unit loads determined by Ministry of Environment data (MOE). It is because the nitrogen fertilization level at the studied field was higher than the recommended rate and the high irrigation and subsequent drainage amount. On the contrary, total phosphorus loads were less than those addressed by MOE since phosphorus fertilization level was lower than that of standard level. Therefore, it was found that fertilization, irrigation, and drainage management are key factors to determine nutrient losses from paddy fields. When the runoff losses of nutrients were compared to applied chemical fertilizer, it was found that 42 to 60% of nitrogen lost via runoff while runoff losses of phosphorus account for 1.3 to 7.6% of the total applied amount during the entire year.