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Characteristics of Plant Community Structure for Vegetation Management Planning of Bonguisan Neighborhood Park, Chuncheon City (춘천시 봉의산근린공원의 식생관리방안을 위한 식물군집구조 특성 연구)

  • Lee, Eun-Seok;Han, Bong-Ho;Kim Jong Yup;Lee, Hak-Gi
    • Journal of the Korean Institute of Landscape Architecture
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    • v.52 no.1
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    • pp.17-33
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    • 2024
  • This study suggests management planning of Bonguisan Neighborhood Park located on the central of Chuncheon city and highly used for citizen's rest and leisure space utilizing its vegetation structure feature. Bonguisan has been the central of the chuncheon since the period of the Three states in Korean history and consistently damaged, especially in present era, an isolation and sererance of its ecosystem has deepen for indiscreet urban development. The percentage of actual vegetation of Boinguisan Neighborhood Park is as follows: Quercus mongolica is 28.5%, Quercus mongolica - Quercus serrata is 2.1%, Pinus densiflora is 15.6%, Pinus densiflora - Quercus mongolica is 15.9%, Betula schmidtii is 1.6%, Robinia pseudoacacia is 5.9%, Pinus koraiensis is 1.6%. Quercus mongolica is distributed on the southwest, northwest, southeast side of region, Pinus densiflora is distributed on the ridge of east and southeast side of region, Betula schmidtii is distributed on the valley of northeast side region and steep slope region which is on the north side of chungwonsa temple. Pinus densiflora community (Comm. I) and Quercus acutissima - Robinia pseudoacacia community (Comm. V) is expected to undergo succession since it's categorized as Quercus spp. and Quercus mongolica community (Comm. II) and Quercus serrata-Quercus mongolica community (Comm. III), Betula schmidtii community (Comm. IV), Pinus koraiensis community (Comm. VI) is expected to maintain. Also for target vegetation and management planning, Vegetation of Bonguisan Neighborhood Park is classified as 1st Natural landscape conservation and improvement type, 2nd Ecological succession type, 3rd Unusual community conservation type, and 4th Recreation and experience type. And we suggested ecological management measure about each management types. For efficient management of Bonguisan Neighborhood Park, it is need to unify management system of it and after designating Pinus densiflora community and Betula schmidtii community which has high ecological preservation value as an ecological landscape protected area and manage it.

Analysis of Verbal Interaction and Perception of Elementary Pre-service Teachers in Science Class Demonstration: Focus on Questioning and Feedback (과학 수업시연에 나타난 언어적 상호작용과 초등 예비교사의 인식 - 발문 및 피드백을 중심으로 -)

  • Jung, Hana;Jhun, Youngseok
    • Journal of Korean Elementary Science Education
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    • v.43 no.1
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    • pp.64-80
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    • 2024
  • This study aims to investigate the characteristics of verbal interaction in science class demonstrations conducted by elementary school pre-service teachers. Specifically, the study intends to examine the use of elements of verbal interaction and the progression of these interactions. Additionally, the study intends to analyze the perception of pre-service teachers about effective questioning and feedback and to determine the correlation between the proportions of the types of questioning and feedback positively perceived by the pre-service teachers and of the types of questioning and feedback used during class demonstration. Toward this end, the study analyzed the science class demonstration videos and class evaluation sheets submitted by 38 fourth-year students at the S University of Education. The results are as follows. First, pre-service elementary school teachers generally use close-ended questions during science class demonstrations. Moreover, they predicted that students would primarily provide the correct responses and would not engage in extended interaction by providing immediate feedback for the responses of the majority of the students. Second, pre-service elementary school teachers perceived the utilization of close-ended questions and immediate feedback in science class demonstrations more favorably than they did that of open-ended questions and delayed feedback. The study observed a weak positive correlation between the positive perception of specific types of questions and feedback and the use of such types in class demonstration. The results demonstrated that pre-service elementary school pre-service teachers tend to engage in fragmented verbal interactions during science class demonstrations. They primarily use close-ended questions and immediate feedback. This tendency is seemingly related to their perception of questions and feedback. Therefore, education institutions for training pre-service teachers need to provide opportunities for reflecting on verbal interactions, which tend to involve close-ended questions and immediate feedback. Lastly, assessing the perception of pre-service teachers of questions and feedback is also necessary.

Suggestions on Expanding Admission Number of Medical School (의과대학 정원 확대에 대한 제언)

  • Eun-Cheol Park
    • Health Policy and Management
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    • v.34 no.2
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    • pp.120-128
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    • 2024
  • From February to now 2024, there continues to be controversy over the expansion of admission number to medical school. Some of the controversy arises from a mix of present and future time points. In the present time point, the controversy over whether physicians are some shortages or not has various aspects. Some aspects are presented as evidence of the physician shortage and others as non-shortage. Also, the presenting evidence of shortage is being disputed, and so is the evidence of the contrary. This controversy over whether there is a shortage or not in the present time point makes it difficult to reach a consensus. In 10 years, the shortage of doctors will increase due to the rapid increase in the elderly population, so the admission number of medical schools will need to be increased. However, the increase must be such that there is minimal deterioration in the quality of medical education. More admission numbers should be allocated to medical schools with a high quality of medical education. This study suggests that large-scale medical schools increase the admission number by 20%-30%, and small-scale medical schools increase the admission number by 40%-50%, if so, the total increasing number is 760 to 1,066. If the 2,000-person increase is enforced, the quality of medical education must be carefully evaluated and the results should be reflected in adjusting the admission number of medical schools. In 20 years later, the admission number of medical schools will have to be reduced. This is because the physician supply is changing to a linear function and the physician demand (medical care demand) is changing to a quadratic function. Even if the current number is maintained, there will be an excess of doctors from 2048, so the medical school admission number must be reduced and its size will be reduced to about 2,000, a 30% reduction from the current number. Because the same reduction rate for all medical schools will result in many small-scale medical schools, the M&A (mergers and acquisitions) strategy should be considered with 40 medical schools and 12 Korean medical schools. In Korea, the main contributor to estimating physician demand is the change in population structure. Due to the rapid decrease in the total fertility rate, future population projections are uncertain. The recent rapid increase in healthcare utilization should be reexamined in the forecasting of physician demand. Since the various factors that affect the estimate of doctor supply and demand are unclear, the estimate of physician supply and demand must be continuously conducted every five years, and the Health Care Workforce Committee must be established and operated. The effects of increasing the admission number of medical schools should be evaluated and adjusted annually.

The Development of a Benthic Chamber (BelcI) for Benthic Boundary Layer Studies (저층 경계면 연구용 Benthic chamber(BelcI) 개발)

  • Lee, Jae-Seong;Bahk, Kyung-Soo;Khang, Buem-Joo;Kim, Young-Tae;Bae, Jae-Hyun;Kim, Seong-Soo;Park, Jung-Jun;Choi, Ok-In
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.15 no.1
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    • pp.41-50
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    • 2010
  • We have developed an in-situ benthic chamber (BelcI) for use in coastal studies that can be deployed from a small boat. It is expected that BelcI will be useful in studying the benthic boundary layer because of its flexibility. BelcI is divided into three main areas: 1) frame and body chamber, 2) water sampler, and 3) stirring devices, electric controller, and data acquisition technology. To maximize in-situ use, the frame is constructed from two layers that consist of square cells. All electronic parts (motor controller, pA meter, data acquisition, etc.) are low-power consumers so that the external power supply can be safely removed from the system. The hydrodynamics of BelcI, measured by PIV (particle image velocimetry), show a typical "radial-flow impeller" pattern. Mixing time of water in the chamber is about 30 s, and shear velocity ($u^*$) near the bottom layer was calculated at $0.32\;cm\;s^{-1}$. Measurements of diffusivity boundary layer thickness showed a range of $180-230\;{\mu}m$. Sediment oxygen consumption rate, measured in-situ,was $84\;mmol\;O_2\;m^{-2}\;d_{-1}$, more than two times higher than on-board incubation results. Benthic fluxes assessed from in-situ incubation were estimated as follows: nitrate + nitrite = $0.18\;{\pm}\;0.07\;mmol\;m^{-2}\;d^{-1}$ ammonium $23\;{\pm}\;1\;mmol\;m^{-2}\;d^{-1}$ phosphate = $0.09\;{\pm}\;0.02\;mmol\;m^{-2}\;d^{-1}$ and silicate = $23\;{\pm}\;1\;mmol\;m^{-2}\;d^{-1}$.

Hydrographic Structure Along $131.5^{\circ}W$ in the Northeastern Pacific in July-August 2005 (2005년 7-8월에 관측한 북동태평양 $131.5^{\circ}W$의 해수특성 및 해양구조)

  • Shin, Hong-Ryeol;Hwang, Sang-Chul
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.3
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    • pp.190-199
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    • 2008
  • To investigate hydrographic structure and characteristics of the tropical ocean in the eastern and the western Pacific, CTD(Conductivity-Temperature-Depth) data along $131^{\circ}W$ and $137^{\circ}-142^{\circ}E$ in July-August 2005 were analyzed. Sea surface temperature along $131.5^{\circ}W$ in summer is highest in the Equatorial Counter Current(ECC) because of the high-temperature water greater than $28^{\circ}C$ moving through the ECC from the western Pacific to the eastern Pacific in spring and summer. Based on the evidence of the presence of low salinity and high dissolved oxygen water in the North Equatorial Current(NEC), we suggested that the low salinity water moved from the Gulf of Panama to the east of Philippine along the North Equatorial Current(NEC). The South Equatorial Current(SEC) had the most saline water from surface to deep layer because the saline water from the Subtropical South Pacific Ocean moved to the north. The salinity minimum layer was observed at 500-1500 m depth along $131.5^{\circ}W$. The water mass with the salinity minimum layer in the north of $5^{\circ}N$ came from the North Pacific Intermediate Water(NPIW) and that in the south of $5^{\circ}N$ came from the Antarctic Intermediate Water(AAIW), which was more saline than the NPIW. Cyclonic cold eddy with a diameter of about 200km was found in $4-6^{\circ}N$. Sea surface temperature along $131.5^{\circ}W$ in the eastern Pacific was lower than along $137^{\circ}-142^{\circ}E$ in the western Pacific; on the other hand, sea surface salinity in the eastern Pacific was higher than in the western Pacific. Subsurface saline water from the Subtropical South Pacific Ocean was less saline in the eastern Pacific than in the western Pacific. Salinity and density(${\sigma}_{\theta}$) of the salinity minimum layer south of $14^{\circ}N$ was higher in the eastern Pacific than in the western Pacific.

Structure of the Phytoplanktonic communities in Jeju Strait and Northern East China Sea and Dinoflagellate Blooms in Spring 2004: Analysis of Photosynthetic Pigments (봄철 제주해협과 동중국해 북부해역에서 식물플랑크톤의 광합성 색소분석을 이용한 군집 분포 특성과 dinoflagellate 적조)

  • Park, Mi-Ok;Kang, Sung-Won;Lee, Chung-Il;Choi, Tae-Seob;Lantoine, Francois
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.1
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    • pp.27-41
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    • 2008
  • Distribution characteristics of phytoplankton community were investigated by HPLC and flow cytometry in Jeju Strait and the Northern East China Sea (NECS) in May 2004, in order to understand the relationship between physical environmental factors and distribution pattern of phytoplankton communities. Based on temperature and salinity data, three distinct water masses were identified; warm and saline Tsushima Warm Current (TWC), which is flowing from northwest of Jeju Island, warm and low saline water at the center of Jeju Strait, which is originated from China Coastal Water (CCW) and relatively cold and high saline water originated from Yellow Sea at the bottom of the Jeju Strait. At Jeju Strait, less saline water (<33 psu) of 15 km width occupied surface layer up to 20 m which located at 20 km offshore and strong thermal front between warm and saline water and cold and less saline water was found in the middle of the Jeju Strait. Vertical transect of temperature and salinity at the NECS also showed that low saline (<33 psu) water occupied the upper 20 m layer and cold and saline water was present at the eastern part. Chl a was measured as $0.06{\sim}3.07\;{\mu}g/L$. Spring bloom of phytoplankton was recognized by the high concentrations of Chl a at the low saline water masses influenced by the CCW and subsurface chlorophyll maximum layer appeared between $20{\sim}30\;m$ depth, which was at thermocline depth or below. Abundances of Synechococcus and picoeukaryote were $0.2{\sim}9.5{\times}10^4\;cells/mL$ and $0.43{\sim}4.3{\times}10^4\;cells/mL$, respectively. Dinoflagellate, diatom and prymnesiophyte were major groups and minor groups were chlorophyte+prasinophyte, chrysophyte, cryptophyte and cyanophyte. Especially high abundance of dinoflagellate was identified by high concentration (>1\;{\mu}g/L$) of peridinin at the bottom of the thermocline, which showed an outbreak of red tide by high density of dinoflagellates. Abundances of picoeukaryote in Jeju Strait were about $5{\sim}10$ times higher than abundance measured in Kuroshio water and showed a good correlation with Chl b (Pras+Viola), which implies the most of population of picoeukaryote was composed of prasinophytes. Prochlorococcus was not detected at all, which suggests that Kuroshio Current did not directly influenced on the study area. Based on the strong negative correlations between biomass of phytoplankton (Chl a) and temperature+salinity, the primary production and biomass of phytoplankton in the study area were controlled by the nutrients supply from CCW.

Spatio-temporal Changes in Macrobenthic Community Structure and Benthic Environment at an Intensive Oyster Culturing Ground in Geoje-Hansan Bay, Korea (굴 양식장 밀집해역인 거제한산만의 저서동물군집 구조와 저서환경의 시.공간적 변동)

  • Yoon, Sang-Pil;Jung, Rae-Hong;Kim, Youn-Jung;Hong, Sok-Jin;Oh, Hyun-Taik;Lee, Won-Chan
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.4
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    • pp.213-228
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    • 2009
  • This study was conducted to investigate spatio-temporal changes in macrobenthic community structure and benthic environmental conditions in Geoje-Hansa Bay, which is the greatest oyster producing site in Korea. Field survey for benthic environment and macrobenthos was seasonally carried out at 15 stations covering oyster farming sites and non-farming sites from February to November, 2008. The grain size of surface sediments was dominated by very fine silt with the mean phi of about $9\;{\Phi}$ and TOC was 1.9% on average. Mean dissolved oxygen content was 8.1 mg/L and lowest in August corresponding to the 2nd degree in seawater quality criteria. Total species number was 351 and mean density was $3,675\;ind./m^2$, both of which were dominated by polychaete worms. Spatio-temporal variation in above two biological variables was great with higher values seasonally in spring and spatially in channels rather than inner bay. Dominant species were Lumbrineris longifolia (21.3%), Aphelochaeta monilaris (17.8%) and Ericthonius pugnax(6.1%), all of which are typical species of organically enriched area. From the multivariate analyses, the whole macrobenthic community was distinguished into two groups of channel and inner bay group. Spatio-temporal changes of macrobenthic community in Geoje-Hansan Bay were related to those of TOC and acid volatile sulfide (AVS). Our results showed that Geoje-Hansan Bay should be intermediately affected by organic pollution, and that such organic enrichment was more remarkable at farming stations in the inner bay.

Seasonal Variations of Microphytobenthos in Sediments of the Estuarine Muddy Sandflat of Gwangyang Bay: HPLC Pigment Analysis (광합성색소 분석을 통한 광양만 갯벌 퇴적물 중 저서미세조류의 계절변화)

  • Lee, Yong-Woo;Choi, Eun-Jung;Kim, Young-Sang;Kang, Chang-Keun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.1
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    • pp.48-55
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    • 2009
  • Seasonal variations of microalgal biomass and community composition in both the sediment and the seawater were investigated by HPLC pigment analysis in an estuarine muddy sandflat of Gwangyang Bay from January to November 2002. Based on the photosynthetic pigments, fucoxanthin, diadinoxanthin, and diatoxanthin were the most dominant pigments all the year round, indicating that diatoms were the predominant algal groups of both the sediment and the seawater in Gwangyang Bay. The other algal pigments except the diatom-marker pigments showed relatively low concentrations. Microphytobenthic chlorophyll ${\alpha}$ concentrations in the upper layer (0.5 cm) of sediments ranged from 3.44 (March at the middle site of the tidal flat) to 169 (July at the upper site) mg $m^{-2}$, with the annual mean concentrations of $68.4{\pm}45.5,\;21.3{\pm}14.3,\;22.9{\pm}15.6mg\;m^{-2}$ at the upper, middle, and lower tidal sites, respectively. Depth-integrated chlorophyll ${\alpha}$ concentrations in the overlying water column ranged from 1.66 (November) to 11.7 (July) mg $m^{-2}$, with an annual mean of $6.96{\pm}3.04mg\;m^{-2}$. Microphytobenthic biomasses were about 3${\sim}$10 times higher than depth-integrated phytoplankton biomass in the overlying water column. The physical characteristics of this shallow estuarine tidal flat, similarity in taxonomic composition of the phytoplankton and microphytobenthos, and similar seasonal patterns in their biomasses suggest that resuspended microphytobenthos are an important component of phytoplankton biomass in Gwangyang Bay. Therefore, considering the importance of microphytobenthos as possible food source for the estuarine benthic and pelagic consumers, a consistent monitoring work on the behavior of microphytobenthos is needed in the tidal flat ecosystems.

Sea Level Variability at a Synoptic Band along the East Coast of Korea and its Causal Mechanism (한국 동해연안의 종관주기 해수면 변동 특성과 발생원인)

  • Jung, Sung-Yun;Yun, Jae-Yul;Park, Tae-Wook;Lim, Se-Han;Oh, Im-Sang
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.2
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    • pp.89-105
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    • 2008
  • Sea level and atmospheric pressure data of 1999-2005 from four stations along the Korean east coast were analyzed to understand the sea level variability and its causal mechanism. The results of the wavelet and the auto-spectrum analyses indicate that the sea level fluctuations of 3-17 day period are statistically significant at the 95% confidence level, especially in spring to early summer. In this period, the coherency between the sea levels and the atmospheric pressures in a cross-spectrum is high, implying the importance of an inverted barometric effect in generation of the sea level fluctuations. To learn about the sea level variability, the cross-spectrum analyses were applied between the sea levels of the adjacent stations. The results show a case of southward phase propagations along the coast, as in 1999, 2003 and 2005, and an another case of no progressive phase lags between the stations, as in 2000-2002, and 2004. The phase speed in the former case is 12-15 m/s, which is a commonly observed phase speed of coastal Kelvin waves. Generation of such fluctuations seems to be related to low pressure cells developed in the Asian continent in spring and summer and moving eastward over the coastal region north of the stations. The latter case of no progressive phase lag, however, occurs when the low pressure cells developed in the continent move along the region south of the stations. In this case, the northeastward phase propagation with a speed of 5-8 m/s is observed along the southwestern coast of Japan.

Trade-off Analysis Between National Ecosystem Services Due to Long-term Land Cover Changes (장기간 토지피복 변화에 따른 국내 생태계서비스 간 상쇄효과(Trade-off) 분석)

  • Yoon-Sun Park;Young-Keun Song
    • Korean Journal of Environment and Ecology
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    • v.38 no.2
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    • pp.204-216
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    • 2024
  • Understanding the trade-off effect in ecosystem services and measuring the interrelationships between services are crucial for managing limited environmental resources. Accordingly, in this study, we identified the dominant trends and increases and decreases in ecosystem services derived from changes in land cover over about 30 years and tracked changes in the relationships between ecosystem services that occurred over time. Through it, we determined the relationship between land cover changes and ecosystem service changes, as well as the distinct characteristics of service changes in different areas. The research primarily utilized the InVEST model, an ecosystem service assessment model. After standardizing the evaluation results between 0 and 1, it went through principal component analysis, a dimensionality reduction technique, to observe the time-series changes and understand the relationships between the services. According to the research results, the area of urbanized regions dramatically increased between 1989 and 2019, while forests showed a significant increase between 2009 and 2019. Between 1989 and 2019, the national ecosystem service supply witnessed a 13.9% decrease in water supply, a 10.5% decrease in nitrogen retention, a 2.6% increase in phosphorus retention, a 0.9% decrease in carbon storage, a 1.2% increase in air purification, and a 3.4% decrease in habitat quality. Over the past 30 years, South Korea experienced an increase in urbanized areas, a decrease in agricultural land, and an increase in forests, resulting in a trade-off effect between phosphorus retention and habitat quality. This study concluded that South Korea's environment management policies contribute to improving ecosystem quality, which has declined due to urbanization, and maximizing ecosystem services. These findings can help policymakers establish and implement forestry policies focusing on sustainable environmental conservation and ecosystem service provision.