• Development and Reproduction
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• v.6 no.1
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• pp.37-44
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• 2002

First sexual maturity, sex ratio, spawning frequency, deposition of the egg capsules and fecundity of the female Rapana venosa(Valenciennes) inhabited in the artificially closed slag deposit area, Gwangyang Bay were investigated by histologicai and visual observations for natural living resource management. The rate of individuals reaching the first sexual maturity was 51.6％ in females measuring 7.1~8.0 cm in shell height, and 100％ in those > 10.1 cm. The total number of egg capsules per individual and the mean number of eggs in an egg capsule were 192~382 and 500, respectively. However, the number of eggs per individual and sizes of egg capsules under lower salinity and deficient food conditions in the closed slag deposit area were smaller than those under the optimum salinity and sufficient food conditions in the open regions. Fecundities of the species were approximately from 96,000 to 191,000 eggs/individual with two to low broods(spawning frequencies) during the spawning season. The duration of development in egg capsules was 18~19 days at about 18~2$0^{\circ}C$. R. venosa is a species whose embryos hatch as veliger larvae, not juvenile snail. The sex ratio of female : male was not significantly different from 1 : 1($\chi$$^2$= 0.23, p>0.05).

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.6
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• pp.639-647
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• 2009

In line with the rapid settlement of information society, the demand for geospatial information and its applications are dramatically increasing. The Project of National Geographic Information System(NGIS) is actively on going to meet up-to-dateness and accuracy of geospatial data. It is fact that the public interest in environmental issues is increasing than ever in accordance with the restoration of the four major rivers, core project of Green New Deal Policy, and the event of the Ramsar General Meeting. Because the Nakdong River Estuary is a place of great importance in both aspects of wetland and environment conservation, a variety of researches related to this area are progressing. Although artificial developments and natural phenomena are rapidly changing the topography and ecosystem of this area, the effort to build topographic DB for change monitoring is very slow. This study describes a Lidar surveying project over the restored wetland Eulsukdo, the southermost part of the Nakdong River, to establish precise topographic DB throughout producing 3D topographical maps and wetland classification maps. The results of this study will make a large contribution to the systematic maintenance and management for the restored Eulsukdo wetland.

• Journal of Korean Society of Rural Planning
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• v.25 no.4
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• pp.13-26
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• 2019

The rural areas in South Korea have changed rapidly in the process of national land development. Rural landscapes have become discoloured, and their attractiveness has decreased as cities have expanded. But the attractiveness or multifunctional values of rural areas has become more important in contemporary society around the world. According to this social demand, the efforts of conserving the rural landscape are of high priority and the recovery of ruralism in the area is required. This study has tried to understand how the public image of ruralism in South Korea has been influenced by the news media. The study retrieved news articles using the web searching portal site from the six keywords, commonly used to refer to ruralism, including 'rural landscape', 'rural community', 'rural tourism', 'rural life', 'rural amenity', and 'rural environment'. News data from the six keywords were also collected respectively from within the year-period of 2004-05, 2007-08, 2012-13, and 2016-17. In the text mining analysis, the nouns with high Degree Centrality were figured out, and the changes by year-period were identified. Then, LDA topic analysis was performed for text datasets of six keywords. As a result, the study found that the news articles gave an informed focus on only a handful of issues such as 'poor rural living condition', 'regional or village improvement projects', 'rural tourism promotion projects', and 'other government support projects'. On the other hand, nouns related to virtues and values in the rural landscape were less shown in news articles. These results have become more apparent in recent years. In the topic analysis, 35 topics were identified. 'village development projects', 'rural tourism', and 'urban-rural exchange projects' were appeared repeatedly in several keywords. Among the topics, there are also topics closely related to ruralism such as 'rural landscape conservation', 'eco-friendly rural areas', 'local amenity resources', 'public interest values of agriculture', and 'rural life and communities'. The study presented an image map showing ruralism in South Korea using a network map between all topics and keywords. At the end of the study, implications for Korean rural area policy and research directions were discussed.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.347-376
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• 2021

Investigating and evaluating regionally distributed plant resources provide fundamental information (inventory) to conserve plant diversity in target areas. Nevertheless, the examination of inventory to collect information in areas with little interest has been insufficient. In this study, the vicinity of Mt. Baegamsan(1,004m) was investigated for plant resources in the central and southern part of the Korean peninsula, which has received low interest. Nine surveys identified a total of 638 taxa consisting of 108 families, 339 genera, 572 species, 12 subspecies, 49 varieties, and 5 forms. One taxon was designated to be the endangered wild plant by the Ministry of Environment, and a total of 29 taxa were designated to be endemic species in Korea. Floristic target species identified by the surveys included 1 taxon for grade V, 13 taxa for grade IV, 36 taxa for grade III, 29s taxa for grade II, and 34 taxa for grade I. A total of 38 taxa were identified to be naturalized plants, and 3 of them were designated as invasive alien plants by the Ministry of Environment. There was a difference in plant distribution between western and eastern areas of Mt. Baegamsan. The endangered and valuable plants for conservation were mainly identified from Mt. Baegamsan peak area, the ridge, and the western area. Considering the plant distribution, the Mt. Baegamsan region, located on Nakdong-jungmaek, was estimated to be dispersal routes for plant expansion and retreat.

• Korean Journal of Plant Resources
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• v.36 no.2
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• pp.133-171
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• 2023

This study was conducted to prepare basic data by analyzing the biological values and environmental factors of algific talus slope in order to respond to climate change due to the greenhouse effect, and to establish plans for forest biodiversity preserving and managing. Meteorological information was measured and the flora of vascular plants were investigated for six algific talus slope by seasonally from 2020 to 2021. As a result of the investigation, the temperature of all 6 algific talus slope was lower than that of the area where the algific talus slope was located in summer, and flora was 101 families, 350 genera, 621 species, 18 subspecies, 57 variants, 7 varieties, 703 taxa. In sum, it is judged that the algific talus slope has sufficient reasons and value to be preserved because it has excellent micrometeorological value from the cold wind blowing in summer and phytogeographical value in which various plants live in a small area. However, in spite of such an important area, the management of algific talus slope is insufficient, and the algific talus slope is damaged or the ecosystem of the algific talus slope is disturbed. Therefore, it is necessary to establish a systematic conservation and management plan by designating algific talus slope as a forest genetic resource reserve and OECM.

• Korean Journal of Plant Resources
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• v.37 no.2
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• pp.203-213
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• 2024

In this study, we investigated the growth and physiological responses of Iris laevigata Fisch. to shading treatments in order to suggest optimal light conditions for ex-situ conservation of the northern lineage plants. For this purpose, a control plant receiving full sunlight and different shading treatments (50%, 75%, 95%) were installed, and leaf mass per area, chlorophyll content and fluorescence response, and photosynthetic characteristics were investigated. I. laevigata developed leaves with higher photosynthetic efficiency to adapt to lower light intensity as shading levels increased. Chlorophyll content increased with increasing shading levels, and leaf mass per area decreased with increasing leaf area. The chlorophyll fluorescence responses Fv/Fm and NPQ did not change with shading, and the activity of the carbon fixation system did not differ between treatments. I. laevigata exhibited a light-saturation point equivalent to that of sun plants and maintained photosynthetic capacity similar to that of controls up to 75% shading. The apparent quantum yield of I. laevigata decreased significantly at 95% shading, indicating adaptation to lower light conditions. It seems that the photosynthetic capacity of I. laevigata decreases when grown under 95% shading level compared to full sunlight, and it is judged that the longer the light is restricted by continuous shading, the more unfavorable the growth will be.

• Journal of Korean Port Research
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• v.13 no.1
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• pp.155-166
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• 1999

The construction of the coastal structures and reclamation work causes the circulation reduced in the semi-closed inner water area and the unbalanced sediment budget of beach results in an alteration of beach topography. Among the various fluid motions in the nearshore zone water particle motion due to wave and wave-induced currents are the most responsible for sediment movement. Therefore it is needed to predict the effect of the environmental change because of development and so the prediction of wave transformation dose. The purpose of this study is to introduce the relation between waves wave-induced currents and sediment movement. In this study we will show numerical method using energy conservation equation involving reflection diffraction and reflection and the surfzone energy dissipation term due to wave breaking is included in the basic equation. For the wave-induced current the momentum equation was combined with radiation stresses lateral mixing and friction Various information is required in the prediction of wave-induced current depending on the prediction tool. We can predict changes in wave-induced current from the distribution of wave especially near the wave breaking zone. To evaluate these quantities we have to know the local condition of waves mean sea level and so on. The results from the wave field and wave-induced current field deformation models are used as input data of the sediment transport and bottom change model. Numerical model were established by a finite difference method then were applied to the development plan of the eastern Pusan coastal zone Yeonhwa-ri and Daebyun fishing port. We represented the result with 2-D graphics and made comparison between before and after development.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.4
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• pp.24-36
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• 2003

This study integrates the revised universal soil loss equation(RUSLE) with a grid-based GIS method to assess the potential risk of soil erosion at the watershed scale. Data used in this study to generate the RUSLE factors include several thematic maps such as land use, topographic and soil maps, together with tabular precipitation data. Based on the RUSLE estimation for all the grids(10m cells) in the corresponding watershed, a cumulative histogram for the annual soil loss can be constructed. As the results, it shows that the 83.5% value of the annual soil loss for the watershed is less than 1ton/ha. However, the above 30% of agricultural land is defined as a medium or very high-risk area(more than 10ton/ha/yr). So it is necessary to establish soil conservation practices to reduce soil erosion based on the field observations.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.111-119
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• 2009

The purpose of this study is to decide the suitability of the land use on eco-city by analysing ecological elements using GIS. Selected ecological elements for suitability analysis were altitude, slope, watershed, biotope, soil productivity, visual sensitivity, vegetation, and green connection. The category of each element was classified into 5 grades, and was given weight according to each element. The maximum value of each element was extracted from overlay analysis process. The result of analysis was classified into 5 grade finally. As a result, land use was proposed to be development, conservation, and preservation area.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.573-581
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• 2001

The purposes of this study are to estimate mean willingness to pay (WTP) for preventing forest fires by contingent valuation method (CVM), and to calibrate the variables affecting WTP. The forest fire prevention fund was utilized as a payment vehicle to elicit respondents' willingness to pay (WTP). A total of 500 adults who reside in Seoul Metropolitan area were selected by two-stage cluster sampling and conducted the face-to-face interview. The scenario was designed to meet the requirements for double-bounded dichotomous choice CVM. More than half of the respondents (64.6%) have a willing to pay for the fund. The mean WTP was \4,532. Therefore a total WTP for the population was \34,165,758,000. The calibration of Weibull proportional hazard model showed that education level, environmental conservation intention and negative consciousness about the effect of forest fire were independent variables strongly influencing the WTP.