• ALGAE
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• v.27 no.1
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• pp.9-19
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• 2012

Phlorotannins are common metabolites produced in kelps that can have deterrent functions against grazers. The factors dictating seasonal patterns of phlorotannin content in northeastern Pacific kelps are not well understood. This study assessed density and grazing of the gastropod Lacuna vincta on the annual canopy-forming kelp Nereocystis luetkeana and the perennial understory species Agarum clathratum, Saccharina latissima and S. groenlandica in Kachemak Bay, Alaska. In addition, we assessed seasonal patterns of environmental variables as possible drivers of phlorotannin concentrations. Phlorotannins occurred in all species, with overall lowest levels in N. luetkeana, and with different seasonal patterns among the four species. Lacuna vincta was most dense on N. luetkeana thalli in the summer and had highest grazing rates on this low-phlorotannin species. However, correlations between L. vincta density and phlorotannin content of each kelp species were not significant. Except for N. luetkeana, there were no correlations between phlorotannin levels and environmental variables. We suggest that kelp life history traits may be more important for phlorotannin patterns in these kelp species than grazers or environmental drivers.

• Journal of Environmental Policy
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• v.5 no.1
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• pp.71-97
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• 2006

This paper explores the history of environmental movements and policymaking in the city of Austin, TX and addresses the most recent element of the city's environmental policy, the Smart Growth Initiative. Austin's intense growth over the last 35 years has increased a growing awareness of environmental impacts by humans. The Austin municipal government has tried to adopt environmental measures and various policy initiatives ranging from comprehensive plans to its latest Smart Growth Initiative. The long history of comprehensive planning and watershed protection ordinances indicate that while environmental issues have continually presented as priority issues, it has failed to integrate as a part of the municipal government. This shows that the efforts of political actors have not been sufficient to sustain progressive environmental regimes with environmental issues despite the initial motivation of the state.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1996.04a
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• pp.17-17
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• 1996

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.507-508
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• 2018

• Journal of Environmental Impact Assessment
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• v.28 no.1
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• pp.49-62
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• 2019

Environmental changes can affect life-history traits, such as growth rate and reproduction, and organisms adapt on a given environmental condition to maximize ecological fitness. This study shows the effects of water temperature and dissolved oxygen level on early growth and accumulated damage in fish using a dynamic-state-dependent model. I have hypothesized that the level of foraging activity is related to growth and stress and so the optimal level can maximize reproductive success - ultimately, fitness. The critical temperature and dissolved oxygen (DO) is also defined as inducing the maximum growth rate at the level. So, the model predicts the highest growth rate at oxygen saturation and lower growth rate at lower or higher level of DO in water. Lower DO (i.e., hypoxia) causes slower growth rate through higher amount of accumulated stress whereas higher DO (i.e., hyperoxia) induces faster growth rate, but smaller body size. In addition, I show that there is lower impact when considering simple or independent environmental factors on environmental assessment. My findings suggest that multiple environmental factors as physiological ecology approach should be considered to improve impact assessment in environmental changes and a further study is needed to develop advanced assessment tools considering multiple environmental factors.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.54.3-55
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• 2018

We present the physical and environmental properties of nearby dwarf elliptical-like galaxies. The present sample consists of ~ 1,100 dwarf elliptical-like galaxies within redshifts 0.01. The morphological types of the present study were determined by Ann, Seo, and Ha (2015) who classified the dwarf elliptical-like galaxies by the five subtypes of dS0, dE, dSph, dEbc, and dEblue. We examine their star formation history using STARLIGHT. The star formation history of dwarf elliptical-like galaxies depends on their subtypes. The luminosities of dS0, dE, and dSph galaxies are dominated by the extremely old stars (${\geq}10^{10}yr$) with $z{\approx}0.0004$ while those of dEbc and dEblue galaxies are mainly due to the young (${\sim}10^7yr$) stars together with the nearly equal contribution by extremely young stars (${\sim}10^6yr$) and old (${\sim}10^9yr$) stars. Young populations have a variety of metallicity, from z=0.0001 to z = 0.04, while old populations have metallicity of z = 0.0001 and z = 0.0004. While the formation history of stars older than ~1010yr depends mainly on the luminosity of galaxies, the formation history of stars younger than ~108yr is mainly affected by their environment. However, luminosity and environment are equally important for the star formation history if there is no star formation at the early phase of galaxy formation.

• Journal of Mushroom
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• v.6 no.3_4
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• pp.103-110
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• 2008

A cultivation of Pleurotus spp. on tree-stumps and logs, was first described at the beginning of the twentieth century. Now Pleurolus spp. is the most popular mushrooms in Korea. Especially, P. ostreatus has been cultivated for many years since artificial cultivation methods were developed in 1980's. Its productivity occurring almost 32% in Korea. To find the vision of mushroom research, the beginning and history of Pleurolus spp. cultivation were introduced worldwide based on Journal of Mushroom Science. The important innovation and history in cultivation were also discussed in Korea.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.126-131
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• 2003

Thirty three species in six subfamilies of Staphylinidae are recognized from Ulleung-do through the survey in 2001. Among them, Thirty one species are newly reported from Ulleung-do. Two species, Anotylus lewisius(Sharp) and Megarthrus aino Cuccodoro, are reported for the first time from Korea.

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.107-114
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• 2009

We investigated the predation behavior of larval damselfly on Daphnia pulex and D. galeata, and compared the life history and morphological defenses in two Daphnia species against larval damselfly and fish kairomones. Larval damselflies showed size-dependent predation behavior and preyed upon smaller daphnids easily regardless light condition. Overall, small D. galeata juveniles were more vulnerable than D. pulex to the larval damselfly predation. D. pulex displayed life history and morphological changes as the anti-predator defenses against larval damselfly as well as large mouth bass, while D. galeata showed the anti-predator defenses to the large mouth bass. Thus, our results revealed that two Daphnia species exhibits different anti-predator defense strategy to increase survivorship.

• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.312-321
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• 2013

Objective: In May 2011, an interview with three United States Forces Korea veterans revealed that chemicals believed to be 'Agent Orange' were buried at Camp Carroll (situated in Waegwan, Chilgok-gun, Gyeongsangbuk-do, Korea) in 1978. Many hazardous chemicals, such as perchloroethylene (PCE), trichloroethylene (TCE), and organochlorines were subsequently found in a joint US-ROK environmental investigation, although dioxins or burial evidence related to 'Agent Orange' have been not uncovered. This study was carried out to investigate the relevance of hazardous chemical exposure and health effects of the residents around Camp Carroll. Methods: The authors conducted a health questionnaire survey among residents around Camp Carroll regarding Waegwan groundwater ingestion, length of residence in Waegwan, and physician-diagnosed disease history (such as cancer, hypertension, diabetes and etc.). Logistic regression was performed to identify the associations between hazardous chemical exposure and physician-diagnosed diseases. Results: Among the 5,320 residents, excluding those living outside the Waegwan area, 3,430 subjects age 30 and over were analyzed. Among females, upon correction of age, smoking history and Camp Carroll working history, a higher distribution in the Waegwan groundwater ingestion group was demonstrated for patients with physician-diagnosed cancer and hypertension. The odds ratios have a tendency to increase with increased length of Waegwan groundwater ingestion. Conclusions: This study may be limited by not adopting a cohort study for the evaluation of factors that may confound environmental exposure. Yet it is meaningful that the correlation between Waegwan groundwater ingestion and chronic diseases were found through regression analysis in female; and further, this outcome may be used as a sampling basis for a secondary epidemiologic study.