• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.880-885
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• 2010

Importance of climate change and its impact on agriculture and environment has increased with a rise of greenhouse gases (GHGs) concentration in Earth's atmosphere. Nitrous oxide ($N_2O$) emission in upland fields were assessed in terms of emissions and their control at the experimental plots of National Academy of Agricultural Science (NAAS), Rural Development Administration (RDA) located in Suwon city. It was evaluated $N_2O$ emissions at different soil water content, soil temperature, and mineral N conditions in a upland cultivating red pepper and soy bean. The results were as follows: 1) There were significant correlation between amount of $N_2O$ emissions and soil temperature, soil water content and mineral N conditions showed $0.528^{**}$, $0.790^{***}$ and $0.937^{***}$ in red pepper field and $0.658^{***}$, $0.710^{***}$ and $0.865^{***}$ in soybean field, respectively. 2) From the contribution rate analysis as to contribution factors for $N_2O$ emission, it appeared that contribution rate was in the order of mineral N (71.9%), soil moisture content (23.6%), and soil temperature (4.5%) in pepper field and mineral N (65.5%), soil moisture contents (19.2%), and soil temperature (15.2%) in soybean field.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.577-589
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• 2021

Soil seed bank community contributes to the long-term conservation of plant diversity and vegetation dynamics, and their decreasing diversity and density with soil depth provide critical perspectives (deterministic and stochastic) for understanding the community disassembly process. We analyzed changes in species composition and diversity and structuring patterns by soil layer (top and bottom), including surface vegetation, in Gwangneung Forest, a mature forest with a vegetation climate in the temperate central part of the Korean Peninsula. From two layers of soil collected with a vertical difference of 10 cm, 934 specimens of 27 families, 40 genera, 44 species, three varieties, and 47 taxa, germinated. Although species diversity and germination density decreased in most comparative characteristics, including growth type, there was no statistical significance due to large deviations. Within-group variability of species composition was similar in the upper and lower soils, as was the decline pattern in co-occurred species (ζ-diversity) and change in species retention probability. The structuring process of the community composition in the two soil layers was fitted with an exponential correlation rather than a power function, demonstrating the dominance of the stochastic process. The pattern in diversity and species turnover according to soil depth in Gwangneung Forest was discovered to be structured by stochastic random events, such as seed vertical movement rather than interaction with trait characteristics.

• Journal of the Society of Disaster Information
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• v.17 no.4
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• pp.667-673
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• 2021

Purpose: The aim of this study is to analyze the trend for the dispatch of the 119 rescue teams to remove the beehive according to the distribution of temperature and time in Busan metropolitan city for 5 years from 2015. Method: From January 2015 to December 2019, 11 fire stations in Busan were dispatched and the source data of rescue and emergency activities were collected. The number of beehive removal dispatches was determined by the Busan Metropolitan Fire Station's jurisdiction over the past five years, and the temperature meteorological factors and honeycomb removal dispatches were analyzed in frequency and percentage. Result: The frequency of dispatch began to increase at an monthly average temperature of more than 20℃ and was higher at 23℃ to 29℃ than other temperature range. The highest frequency of dispatch was 7,900 cases in 2017. In particular, we found that the start timing of the honeycomb removal is getting faster as the year goes by. Gijang-gun had the largest frequency of dispatch, and Haeundae-gu, Geumjeong-gu, and Nam-gu were found to have a higher that. Conclusion: We found that the start timing of the honeycomb removal is getting faster as the year goes by and temperature changes. The results of this study are considered to be useful in future studies of wasps in urban areas.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.516-529
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• 2021

Coniferous forests in the Baekdudaegan protected area are gradually losing their landscape diversity and uniqueness along with their ecological stability due to changes in vegetation composition and structures caused by various disturbance factors, such as climate change, vegetation succession, and human interference. This study provides basic data for establishing a comprehensive conservation plan for coniferous forests in the Baekdudaegan protected area. We classified the vegetation unit types using the Zurich-Montpellier School of Phytosociology and two-way indicator species analysis methods and analyzed the species diversity and structural characteristics based on the vegetation information of 755 stands collected in the natural resources change survey of the Baekdudaegan mountains (2016 to 2020) by the Korea Forest Service. Therefore, the vegetation of the coniferous forests of theBaekdudaegan protected area was classified into 15 types under the vegetation unit hierarchy of two community groups, four communities, seven sub-communities, and 14 variants. Furthermore, we compared the total coverage among vegetation types, importance values, constancy classes, life-forms, and diversity indices. Additionally, the average total coverage and number of species per 100 m² of all coniferous forests were 232% and 21 species, respectively, with the species diversity and dominance indices averaging 1.907 and 0.222, respectively.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.2
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• pp.168-174
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• 2021

According to the World Agricultural Productivity Report, the current annual average growth rate of agriculture is 1.63%, which is lower than 1.73% to support the world's 10 billion people, which is growing by 2050. The demand for food, feed, and bioenergy is not growing enough to continue to meet the demand, and it is predicting a future food shortage. The purpose of this study was to create a regional irrigation control model for the purpose of reducing the production cost of crops, increasing production, and improving quality, and presenting a model that can give advice to farmers who start farming in the region. The irrigation control modeling presented in this study means to represent the change of medium weight·supply liquid·drainage amount due to changes in the root zone environment according to the passage of time and climate in a graph model. For water control modeling, we collected data on the change in the amount of the root zone environment and the weight of the badge·supply amount·drainage amount from March to June in Nonsan, Buyeo, and Yesan regions in Chungnam Province through the measuring device of the Ministry of Environment in the root region. We set up the parameters for derivation and derived an irrigation control model that can confirm the change in weight·supply liquid·drainage amount over time through the parameters.

• Journal of Marine Life Science
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• v.4 no.1
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• pp.14-21
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• 2019

This review paper discussed the decadal fluctuations in the catch of the common squid, Todarodes pacificus (T. pacificus) by focusing on migration and distribution patterns. Since 1980s, changes in T. pacificus catches were due to climate regime shift in Korean waters. Fluctuation patterns of catches were different between the East Sea and the Yellow Sea. Generally PDO (Pacific Decadal Oscillation) phase shows a negative correlation with strength of warm current to the East Sea. In 1980s when PDO was positive phase (+), T. pacificus catch was higher in the Yellow, but it was lower in the East Sea. In 1990s when PDO was negative phase (-), T. pacificus catch showed opposite trend compared with 1980s. Such spatial and decadal fluctuations of T. pacificus catch were due to its northward migration along with the warm current or southward movement against the current. In the East Sea, strong (weak) warm current period, the current path has been shifted toward the East Sea coast of Korea (central East Sea or the coast of Japan). It has a correlation with PDO. In the positive PDO phase (1980s), the fishing ground was located on the eastern side of Ulleungdo, whereas during negative PDO phase (1990s), they were situated near the southeastern coast of the Korean peninsula. In the 1980s, volume transport passing into the Yellow Sea increased, whereas volume transport in the East Sea decreased. This is one of major reason increasing T. pacificus larvae in the Yellow Sea.

• 한국사회정책
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• v.25 no.2
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• pp.191-217
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• 2018

At the turn of the century, social policy in both developed and developing countries confronts new challenges and risks caused by the multiple crises in finance, food, energy and climate change. Changes in the structures of risks are particularly significant. In addition, the global economic crisis starting in 2008 has provided a new context of the global political economy. Both developed and developing countries have responded to these new challenges and risks differently. What risks do these responses aim to address? How can these responses address these risks? Can these diverse responses offer lessons for lower income economies attempting to address social development challenges alongside economic growth in the globalised and increasingly uncertain 21st century context? This paper aims to provide a critical review of the new trends, phenomena or directions of social policy discourse and practice to respond to the new risks in the context of development. Explaining the nature and forms of new challenges and risks and pointing out the potentials and limitations of social policy discourse, it introduces the key points of the previous research we have to keep in mind in formulating alternative social policy approaches. General principles and core elements of social policy in addressing new challenges and risks in the $21^{st}$ century, which are particularly visible in social policy reforms in emerging economies, are highlighted as a conclusion.

• Journal of Korean Society of Disaster and Security
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• v.14 no.3
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• pp.1-16
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• 2021

Recently, large-scale projects are required in the water resources sector considering safety and publicitythe due to uncertainty of securing water resources and changes in the ecological environment by climate change. Among these large-scale projects, the projects that fall under the preliminary feasibility study are determined by comprehensive analysis based on economic analysis, policy analysis, and balanced regional development analysis. However, most of the results of the preliminary feasibility study showed a tendency to depend heavily on economic analysis. For this reason, projects in non-metropolitan areas sometimes fail in the preliminary feasibility study. To supplement this point, the Korea Development Institute revised the standard guidelines for preliminary feasibility studies for water resources sector projects that place a high weight on policy feasibility analysis. Therefore, the objective of this study is to analyze the cases of the preliminary feasibility study conducted previously and to suggest the direction of policy analysis in the preliminary feasibility study for water resources sector projects. For this, we analyze preliminary feasibility studies conducted for 18 years from 2002 to 2019, and suggest direction of policy analysis method using the benefit items not included in the economic analysis.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.5
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• pp.187-194
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• 2021

The damage caused by typhoons is gradually increasing due to the climate change recently. Hence, many studies have been conducted over a long period of time on various factors that determine the characteristics of storm surge, and most of relationships have been discovered. Because storm surge is complexly determined by various factors, it often show different results and draw different conclusions. For this reason, this study was conducted to understand the various characteristics of storm surge caused by changes in the forward speed of typhoons. This study was carried out with a numerical model, and the effect of forward speed could be analyzed by simplifying other factors as much as possible. When forward speed is increased, storm surges caused by typhoons tended to increase gradually. The storm surge showed a wide and gentle increase at a slow speed, but a narrow and steep one at a fast speed. In the case of the same forward speed, it was found that the storm surge was significantly influenced by the water depth of actual sea area. It was confirmed that the change in forward speed after passing Jeju Island did not significant affect on the storm surge in the south coast of Korea.

• Journal of Ecology and Environment
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• v.44 no.4
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• pp.275-285
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• 2020

Background: In Korea, Symplocos prunifolia Siebold. & Zucc. is only found on Jeju Island. Conservation of the species is difficult because little is known about its distribution and natural habitat. The lack of research and survey data on the characteristics of native vegetation and distribution of this species means that there is insufficient information to guide the management and conservation of this species and related vegetation. Therefore, this study aims to identify the distribution and vegetation associated with S. prunifolia. Results: As a result of field investigations, it was confirmed that the native S. prunifolia communities were distributed in 4 areas located on the southern side of Mt. Halla and within the evergreen broad-leaved forest zones. Furthermore, these evergreen broad-leaved forest zones are themselves located in the warm temperate zone which are distributed along the valley sides at elevations between 318 and 461 m. S. prunifolia was only found on the south side of Mt. Halla, and mainly on south-facing slopes; however, small communities were found to be growing on northwest-facing slopes. It has been confirmed that S. prunifolia trees are rare but an important constituent species in the evergreen broad-leaved forest of Jeju. The mean importance percentage of S. prunifolia community was 48.84 for Castanopsis sieboldii, 17.79 for Quercus acuta, and 12.12 for Pinus thunbergii; S. prunifolia was the ninth most important species (2.6). Conclusions: S. prunifolia can be found growing along the natural streams of Jeju, where there is little anthropogenic influence and where the streams have caused soil disturbance through natural processes of erosion and deposition of sediments. Currently, the native area of S. prunifolia is about 3300 ㎡, which contains a confirmed population of 180 individual plants. As a result of these low population sizes, it places it in the category of an extremely endangered plant in Korea. In some native sites, the canopy of evergreen broad-leaved forest formed, but the frequency and coverage of species were not high. Negative factors that contributed to the low distribution of this species were factors such as lacking in shade tolerance, low fruiting rates, small native areas, and special habitats as well as requiring adequate stream disturbance. Presently, due to changes in climate, it is unclear whether this species will see an increase in its population and habitat area or whether it will remain as an endangered species within Korea. What is clear, however, is that the preservation of the present native habitats and population is extremely important if the population is to be maintained and expanded. It is also meaningful in terms of the stable conservation of biodiversity in Korea. Therefore, based on the results of this study, it is judged that a systematic evaluation for the preservation and conservation of the habitat and vegetation management method of S. prunifolia should be conducted.