The Characteristics of the Cultural Tourism Resources Distribution along the Nakdong River Basin
Yhang, Wii-Joo 835
Many various kinds of tourism resources have been distributed along the Nakdong river basin. Previous researches have focused mainly on environmental studies, including water quality control, industrial use of water, biodiversity, etc, with little research done in the field of tourism studies. Central to this study, therefore, is the identification and analysis, from the perspective of cultural tourism, of the area's distribution and characteristics of cultural properties registered by the MOCT. Review of related literature reveals : 1) spatial range bound with the jurisdiction of the river basin like DREO and NRBEO ; 2) analytical subjects limited to cultural properties designated by the three different administrative units of government, city and province. Along with the DREO's predominance over the NRBEO in the total number of cultural properties, the result finds that two cities, Andong and Gyeongju of Gyeongbuk are assigned ownership of most of the cultural properties under the jurisdiction of DREO, while Gyeongnam that of most of the ones under the NRBEO. However, those findings suggest the simple number of cultural properties with no significant level of importance and rarity value reflected. Therefore, future studies need to develop quantified modelling keeping cultural variables in mind and create cultural indices of the competitiveness of the local governments.
Ecological Modeling for Estimation of Environmental Characteristics in Masan Bay
Kim, Dong-Myung 841
The ecosystem model was applied to estimate the regional distribution of the net production(or consumption) of phytoplankton and the net uptake(or regeneration) rate of nutrients in Masan Bay for scenario analysis to find a proper management plan. At the surface level, net production of phytoplankton is 200 mgC/㎡/day at the entrance of the bay, and 400∼1000 mgC/㎡/day at the center of the bay. The inner area of the bay showed more than 2000 mgC/㎡/day. All areas of the bottom level have a net consumption, with the center of the bottom level showing more than 600 mgC/㎡/day. For dissolved inorganic nitrogen, the results showed a net uptake rate of 100∼900 mg/㎡/day at the surface level. It showed that the net regeneration is above 50 mg/㎡/day at the bottom level. For dissolved inorganic phosphorus, the net uptake rate showed 10.0∼80.0 mg/㎡/day at the surface level, and the regeneration rate showed 0∼20.5 mg/㎡/day at the bottom level. Therefore, in order to control the water quality in Masan Bay, it is important to consider the re-supplement of nutrients regenerated in the water column.
Bacterial Die-Off in Continuous River Water Flow System
Kong, Surk-Key;Toshiuki Nakajima 847
It was examined carefully that the bacterial die-off between Chlorella vulgaris and E. coli. W3110 was tested through adding TOC (total organic carbon) with the lab-scaled continuous river water flow system (CRWFS). Artificial synthetic wastewater was applied at two levels of organic carbon concentration; 1,335 mg/l in treatment type 1 and 267 mg/l in type 2. In both types, the population densities of Chlorella vulgaris were similar in a maximum 8.25 ${\times}$ 10$\^$6/ cells/ml (type 1) and 6.925 ${\times}$ 10$\^$6/ cells/ml (type 2). The maximum densities of E. coli. W3110 were 2.0 ${\times}$ 10$\^$8/ colony forming unit (CFU)/ml in type 1 and 3.9 ${\times}$ 10$\^$8/ CFU/ml in type 2. The densities increased for 11 days in type 1 and 4 days in type 2, then decreased rapidly till the 35th day, then slightly increased again. This trend was prominent in type 2. It implied that a wider range of nutrients was required in the growth of heterotrophic bacteria in type 2 than in type 1. We could not expect successful bacterial die-off if the wastewater retention time was not furnished sufficiently.
Atmospheric CO2 Uptake by Pinus densiflora and Quercus mongolica
Jo, Hyun-Kil;Ahn, Tae-Won 853
Plants sequester atmospheric CO$_2$, a major agent of climate change, during the growing periods and mitigate its rising accumulation in the atmosphere. Pinus densiflora and Quercus mongolica are the native tree species dominant in the temperate forests of Korea. This study quantified the annual CO$_2$ uptake by the two species at forest sites in Chuncheon in the middle of the country. The quantification was based on seasonal measurements of CO$_2$ exchange rates under natural conditions by an infrared gas analyzer over the growing season (1999). The monthly CO$_2$ uptake per unit leaf area ranged from 1.6-6.7 mg/d㎡/h for P. densiflora and from 3.7-8.9 mg/d㎡/h for Q. mongolica, with a maximum in mid-summer. An equation for each species was generated to estimate easily the annual CO$_2$ uptake by total leaf area per tree, which subtracted the CO$_2$ release (i.e. respiration) by leaves and woody organs from the gross CO$_2$ uptake (diurnal uptake and release by leaves). Annual CO$_2$ release by leaves and woody organs accounted for 58-73% of the gross CO$_2$ uptake across tree specimens. Annual CO$_2$ uptake per tree increased with increasing dbh (stem diameter at breast height) for the study diameter range, and was greater for Q. mongolica than for P. densiflora in the same dbh sizes. This was mainly associated with a greater total leaf area in the former. For example, the annual CO$_2$ uptake by one tree with dbh of 25 cm was 35.6 kg/yr for P. densiflora and 47.9 kg/yr for Q. mongolica. The results from this study can be applied to evaluate an atmospheric CO$_2$ reduction of woody plants by forest type and age class.
Effects of Polyelectrolyte Dosage, Kaoline Particles and pH on Flocculation of Humic Acid by Catonic Polyelectrolytes
Kam, Sang-Kyu;Kim, Dae-Kyoung;Lee, Min-Gyu 861
Using a simple continuous optical technique, coupled with measurements of zeta potential, the effects of polyelectrolyte dosage, kaoline particles and pH on flocculation of humic acid by several cationic polyelectrolytes, have been examined. The charge density of a polyelectolyte is important in determining the optimum dosage and in the removal of humic acid. The optimum dosage is less for the polyelectrolytes of higher charge density and is the same regardless of the presence of kaoline particles of different turbidity. At the dosage, the removal of humic acid is higher for the polyelectrolytes of higher charge density and the zeta potential of humic acid approaches to near zero, With increasing pH of humic acid, the optimum dosage increases and the flocculation index value obtained at the dosage decreases in the following pH 7 > pH 5 > pH 9, regardless of polyelectrolytes.
Complexation of Co-contaminant Mixtures between Silver(I) and Polycyclic Aromatic Hydrocarbons
Yim, Soo-Bin 871
The complexation of co-contaminant mixtures between Ag(I) and polycyclic aromatic hydrocarbon (PAH) molecules (naphthalene, pyrene, and perylene) were investigated to quantify the equilibrium constants of their complexes and elucidate the interactions between Ag(I) and PAH molecules. The apparent solubilities of PAHs in aqueous solutions increased with increasing Ag(I) ion concentration. The values, K$_1$ and K$_2$ of equilibrium constants of complexes of Ag(I)-PAHs, were 2.990 and 0.378, 3.615 and 1.261, and 4.034 and 1.255, for naphthalene, pyrene, and perylene, respectively, The K$_1$and K$_2$ values of PAHs for Ag(I) increased in the order of naphthalene < pyrene < perylene and naphthalene < pyrene ≒ perylene, respectively, indicating that a larger size of PAH molecule is likely to have more a richer concentration of electrons on the plane surfaces which can lead to stronger complexes with the Ag(I) ion. For the species of Ag(I)-PAH complexes, a 1:1 Ag(I) : the aromatic complex, AgAr$\^$+/, was found to be a predominant species over a 2:1 Ag(I) : aromatic complex, Ag$_2$Ar$\^$++/. The PAH molecules with four or more aromatic rings and/or bay regions were observed to have slightly less affinity with the Ag(I) ion than expected, which might result from inhibiting forces such as the spread of aromatic $\pi$ electrons over o wide molecular surface area and the intermolecular electronic repulsion in bay regions.
Contamination of Tributyltin in Sediment from Four Bays in the Southeastern Part of Korea
Park, Hee-Gu;Kim, Sang-Soo;Moon, Hyo-Bang 881
Spatial and vertical variations of butyltins(BTs) were investigated in polluted sediments from Jinhae, Busan, Ulsan and Yeongil Bays located in the southeastern part of Korea. Tributyltin(TBT) as a dominant species was detected in 18 of the 20 surficial sediments, and TBT levels were lower that for those in heavily polluted areas worldwide, ranging from 12 to 766 ng Sn/g dry wt. Distribution of TBT levels among bays was not significantly different (p=0.286, ANOVA). The horizontal distributions observed at 20 sites suggests that TBT concentrations are still high in polluted sites around harbors and industrial complexes. The sedimentary records a peak in the early 1990s in Jinhae Bay, in the mid 1980s in Ulsan Bay and in the late 1970s in Yeongil Bay except for Busan Bay which had a homogenous profile. In paricular, TBT at the surface sediments of four core samples still had high levels. From the horizontal and vertical results, it could be assumed that TBT inputs in the sediments were not reduced significantly compared to past levels. The annual accumulation rates estimated using the sedimentation rates and the concentration of surficial sediments exhibited that the accumulation rate of Ulsan Bay was greater than the rates for Jinhae and Yeongil Bays.
Distribution of Pyrethroid Insecticides in a Nursery Drainage Channel
Lee, Sang-Jin;Shin, Hyun-Moo 891
The objectives of this study wre to investigate the effects of two synthetic pyrethroids, bifenthrin(BF) and permethrin(PM), in runoff and to evaluate the effects of suspended solids (SS) in the transport of pyrethroid along the drainage channel. Monitoring of BF and PM was conducted with the runoffs as well as in sediments existing along the drainage channel at a nursery site located in southern California, USA. This study also suggests Best Management Practices (BMPs) to alleviage the pollution caused by heavy usage of pyrethroid insecticides at nursery sites. Due to a high affinity to solid particles of pyrethroid insecticides, the concentrations of BF and PM were proportional to the SS contents along the drainage channel. This study suggests that alleviation of pyrethroids existing in runoffs could be controlled by the removal of suspended solids in runoffs and potential implications of current drainage channels for mitigation of pesticides associated with runoffs.