• Animal cells and systems
• /
• v.3 no.1
• /
• pp.29-39
• /
• 1999

Current data on reproductive characters of endemic and native species are essential to provide a strategy for the conservation of these species. Red pine (Pinus densiflora Sieb. & Zucc.) is one of the dominant, native tree species in Korea, but its reproductive ecology is not well-known. In 1997, the pattern of variation in cone and seed yields contributing to the conservation of declining populations of red pines was examined. Plant height and dbh were measured, and several new cones were collected from each tagged tree after counting the number of cones on each tree. For a subset of cones sampled, the number of fertile scales, the number of seeds at three development stages (early/late aborted, and filled seed), seed wing size, wing color, and individual filled seed mass were measured. The three sites which differed significantly in mean plant size also differed in mean cone and seed production per plant. However further analyses showed that most variation in characters examined occurred among plants within sites, but not among sites. An average of 90% of the potential seeds on the cones aborted at an early developmental stage, demonstrating that early abortion is a major factor affecting the number of filled seeds per cone. Individual seed mass was the only character which exhibited significant variations among sites as well as among trees within sites. Individual seed mass was overall negatively correlated with both the percentage of late abortion and the number of old cones per plant, suggesting that both the past and current years' reproductive activities have caused variations in seed mass. The potential dispersal distance of red pine seeds is quite large. However, wing loading was correlated with seed mass and number in a complex pattern across the sites. Distribution of seeds with varied colored wings differed among sites and among trees within sites. These results suggest that red pines at different sites might possess different strategies to cope with selection pressures acting during the final phase of reproduction, from seed dispersal to establishment. Then the ‘fitted’ red pine trees at each site should be identified and managed to conserve or restore populations.

• Journal of Korean Society of Rural Planning
• /
• v.28 no.1
• /
• pp.71-79
• /
• 2022

Recently, alarming rates of climate change have amplified the importance of water conservation in the agricultural sector; emphasizing the implementation of an integrated approach as the principal water management strategy. As part of comprehensive measures to cope with drought in the agricultural and rural sectors, water-saving education models and pilot projects for farmers' education have been implemented since 2016, but these activities were launched as a one-time project in limited areas. Therefore, systematic and extensive efforts are required to highlight the site-specific and tangible benefits of water-saving education and public relations projects. As part of this study, educational sessions and surveys were conducted in the Yeoju-Icheon, Seosan-Taean, and Gyeongju areas to reflect the on-site applicability of the water-saving education model. Based on the survey of previous studies, a total of 16 water-saving effectiveness factors were developed and the effectiveness was derived for each factor. As a result of farmer education, the overall effectiveness evaluation score of 1.13 increased to 3.34, and the effectiveness of each factor was also improved. These water-saving education effectiveness factors can be used as basic data for determining and launching future policies or systems to improve the water-saving education of farmers. In addition, this study raises the need to prepare feasible related systems that can lead farmers to actively participate in water management and conservation and to promote systematic and continuous water conservation education and promotion policies.

• Korean Journal of Environment and Ecology
• /
• v.37 no.2
• /
• pp.140-150
• /
• 2023

The Eurasian otter (Lutra lutra) is an apex predator of the riparian ecosystem. It is a keystone and an indicator species; consequently, its presence suggests a sustainable water environment. Otter is a keystone species as a predator at the top of the food web in the aquatic environment and an indicator species representing the health of the aquatic environment. Although Eurasian otters disappeared from the Han River urban water system because of anthropogenic activities like habitat destruction, poaching, and environmental pollution in the 1980s, the species were sighted in the Cheonggye Stream, Jungrang Stream, and Seongnae Stream, which are urban sections of the Han River, in 2016 and 2021. Therefore, it is pertinent to assess the habitat potential in the area for conservation and management measures to ensure its permanent presence. However, existing studies on otter habitats focused on natural rivers and reservoirs, and there is a limit to applying them to habitats artificially confined habitats in narrow spaces such as tributaries in urban areas of the Han River. This study selected the Cheonggye Stream, an artificially restored urban stream, to evaluate its potential as a habitat for Eurasian otters in urban water environments using the habitat suitability index (HSI). The HSI was calculated with selected environment attributes, such as the cover, food, and threat, that best describe the L. lutra habitat. According to the results, the confluence area of Seongbuk Stream and Cheonggye Stream and the confluence area of Cheonggye Stream and Jungnang Stream were suitable otter habitats, requiring appropriate conservation efforts. The HSI model suggests a valuable method to assess the habitat quality of Eurasian otters in urban water environments. The study is crucial as it can help rehabilitate the species' populations by identifying and managing potential Eurasian otter habitats in highly urbanized areas of the Han River basin and its tributaries.

• Korean Journal of Environmental Biology
• /
• v.37 no.4
• /
• pp.508-525
• /
• 2019

Algific talus slopes provide microclimates suitable for disjunct or relict populations of northern plant species at low elevation habitats in the temperate zones. The propose of this study was to assess the phytogeographical significance and produce a strategy for the comprehensive conservation of the vegetation on algific talus slopes. Therefore, we studied the floristics of bryophytes on 15 algific talus slopes in Korea. The bryophytes on the algific talus slopes in Korea consisted of 59 families, 138 genera, 226 species, two subspecies, and five varieties, totaling 233 taxa. Peculiarly, many northern bryophytes, such as Andreaea rupestris var. fauriei (Besch.) Takaki., Buxbaumia minakatae S. Okamura, Racomitrium lanuginosum (Hedw.) Brid., Hylocomium splendens (Hedw.) Schimp., and Pleurozium schreberi (Willd. ex Brid.) Mitt. were found on the algific talus slopes. Of them, unrecorded species from south Korea numbered 14 taxa and unrecorded species from the Korean peninsula numbered seven taxa. A similarity analysis based on the bryophyte flora showed that the index of similarity between regions with similar environmental factors was high. This means that the bryophyte flora composition on each algific talus slopes was affected by topography and microclimate. Algific talus slopes are phytogeographically significant microhabitats where northern plant species that advanced southward during the latest glacial age have been isolated and adapted. However, algific talus slopes have constantly been destroyed or damaged by humans without consideration of conservation. Conservation strategies to ensure the biodiversity and effective management of algific talus slopes in Korea are discussed in detail.

• The Korean Journal of Mycology
• /
• v.39 no.3
• /
• pp.198-204
• /
• 2011

This study was carried out to investigate occurence of microbiales density and characteristics of xylanase produced by those in Janggyeong Panjeon. Cladosporium cladosporioides H1, Penicillium citreonigrum H3, Penicillilum toxicarium H4, Aspergillus versicolor H6, Acremonium alternarium H7 isolated from Janggyeong Panjeon produced xylanase, which had different production rates and specialized activities in an acidic condition. Cladosporium cladosporioides H1, Aspergillus versicolor H6, and Acremonium alternatum H7 produced xylanase at a faster rate than other fungi. A xylanase of Cladosporium cladosporioides H1 and Penicillilum toxicarium H4 showed a high thermostability in an acidic condition. As results, this study may lead to the development of a strategy for preservation of organic cultural heritages.

• Journal of Wetlands Research
• /
• v.26 no.1
• /
• pp.10-20
• /
• 2024

The conservation and restoration of wetlands are essential tasks for the sustainable development of human society and the environment, providing vital benefits such as biodiversity maintenance, natural disaster mitigation, and climate change alleviation. This study aims to analyze the strategic interactions and interests among various stakeholders using game theory and to provide significant grounds for policy decisions related to wetland restoration and development. In this study, hypothetical scenarios were set up for three types of cities: large, medium, and small. Stakeholders such as governments, development companies, environmental groups, and local residents were identified. Strategic options for each stakeholder were developed, and a payoff matrix was established through discussions among wetland ecology experts. Subsequently, non-cooperative game theory was applied to analyze Nash equilibria and Pareto efficiency. In large cities, strategies of 'Wetland Conservation' and 'Eco-Friendly Development' were found beneficial for all stakeholders. In medium cities, various strategies were identified, while in small cities, 'Eco-Friendly Development' emerged as the optimal solution for all parties involved. The Pareto efficiency analysis revealed how the optimal solutions for wetland management could vary across different city types. The study highlighted the importance of wetland conservation, eco-friendly development, and wetland restoration projects for each city type. Accordingly, policymakers should establish regulations and incentives that harmonize environmental protection and urban development and consider programs that promote community participation. Understanding the roles and strategies of stakeholders and the advantages and disadvantages of each strategy is crucial for making more effective policy decisions.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.15 no.4
• /
• pp.111-118
• /
• 2012

The purpose of this study is to work out strategy for utilization of Environmental Conservation Value Assessment Map (ECVAM) using the user survey. It surveyed system users of ECVAM about its recognition and satisfaction. The results of the survey, the ECVAM became more popular and were highly satisfied with updated data. Especially, the study found a relationship between the satisfaction of ECVAM and accuracy, utilization, and convenience of the system. However, the satisfaction has a difference between user groups, a government official and a agent for EIA including researchers. The satisfaction of the agent group was affected by the convenience, the accuracy, and the utilization in order. In the other hand, the satisfaction of the government official group was affected by the utilization, the convenience, the accuracy, and recognition in order. Therefore, we need to adopt different strategies for educations of ECVAM and publicity activities depending on user groups. To increase the satisfaction of ECVAM, we should research not only to attain pinpoint accuracy, but also to suggest the guideline to utilize the map for a government official.

• International Journal of High-Rise Buildings
• /
• v.2 no.4
• /
• pp.331-340
• /
• 2013

The main topic of this paper is to show a possibility of indoor air quality enhancement and the fan energy savings in underground parking facilities by applying the demand-controlled ventilation (DCV) strategy based on the real-time variation of the traffic load. The established ventilation rate is estimated by considering the passing distance, CO emission rate, idling time of a vehicle, and the floor area of the parking facility. However, they are hard to be integrated into the real-time DCV control. As a solution to this problem, the minimum ventilation rate per a single vehicle is derived in this research based on the actual ventilation data acquired from several existing underground parking facilities. And then its applicability to the DCV based on the real-time variation of the traffic load is verified by simulating the real-time carbon monoxide concentration variation. The energy saving potentials of the proposed DCV strategy is also checked by comparing it with those for the current underground parking facility ventilation systems found in the open literature.

• Journal of Power Electronics
• /
• v.18 no.6
• /
• pp.1771-1779
• /
• 2018

Modern trams with a super capacitor have gained a lot of attention in recent years due to its reliability, convenience, energy conservation and environmental friendliness. Because of its special charging characteristic, the traditional charging structure and control strategy cannot satisfy its charging requirements. This paper presents a new charging topology for fast charging modern trams with a super capacitor and it designs a controller using continuous control set model predictive control (CCS-MPC). There are three contributions in this paper. First, a new charging structure is designed and its mathematics model is derived. The cascade structure is adopted instead of the parallel structure to simplify the control process and to keep the rated power of the controllable part low. Second, a MPC control strategy is proposed to satisfy the charging characteristic. The optimal control signal can be obtained by solving the designed optimization problem. The optimal control signal is related to the discrete control action. In addition, mapping between the continuous control signal and the discrete control action is designed. Third, a semi-physical experimental platform is built to verify the proposed topology and control method. The simulation model and experiment platform are built to verify the correctness of the new structure and its control method. The results obtained show that the new topology can work effectively.

• The Korean Journal of Ecology
• /
• v.27 no.3
• /
• pp.185-192
• /
• 2004

Vegetation established through the natural process, such as Quercus mongolica, Pinus densiflora, Q. variabilis, Q. acutissima, Carpinus laxiflora, Q. aliena and Q. serrata communities and artificially introduced vegetation, which are composed of Larix leptolepis and P. rigida plantations, are established in the mountainous land of the Mt. Songnisan National Park. On the other hand, the developed lands, which are consisted of agricultural folds, residential areas, commercial areas related to tourism, etc. appear in the lowland around streams. Based on the spatial distribution of vegetation, the southern district, which is attributed to Naesongni-myun by administrative system, showed higher natural degree and vegetation diversity. However, most of the other districts, which are attributed to Cheongcheon- and Chilseong-myuns, are covered with the Korean red pine forest, a product of artificial influence, and plantation also occupied higher percentage. Thereby both vegetation diversity and natural degree are lowering. A result of ordination by DCA showed that sands tended to be arranged by depending on the topographic condition. Species diversity of plant communities was higher in broad-leaved stands rather than in coniferous ones and in stands of the early stage than in ones of the late stage. The result of analysis on vegetation dynamics implied that vegetation of this region would be dominated by Carpinus laxiflora, Quercus mongolica and Pinus densiflora communities in the future. However, considered occurrence the of disturbance and response of vegetation on that, this estimation may different somewhat from an actual situation. Conservation strategies of the Mt. Songnisan National Park were discussed in viewpoints of landscape ecology, and conservation of major plant communities and biodiversity.