• Title/Summary/Keyword: Ecological information

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An Ecological Study on the Sand Dollar, Astriclypeus manni (VERRIL 1867), in Hamdock, Cheju Korea (제주도 함덕 연안에 서식하는 구멍연잎성게, Astriclypeus manni (VERRIL 1867)의 생태학적 특성에 관한 연구)

  • KANG DO-Hyung;CHOI Kwang-Sik;CHUNG Sang-Chul
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.3
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    • pp.345-352
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    • 1999
  • The sand dollar, Astriclypeus manni is commonly encountered on a subtidal sand bottom along the coast of Cheju Island. limited information has been reported on their ecology despite their natural abundance. This study reports ecology and an annual reproductive cycle of the sand dollars present at Hamdock, northern coast of Cheju Island. A. manni collected from Hamdock revealed that they are 80 to 200 mm in test diameter. Sediment Brain size analysis indicated that A. manni mostly occurs on medium (particle diameter of 500 $\mu$m) to very find sand (particle diameter of 125 $\mu$m), particularly on fine sand (particle diameter of 250 $\mu$m). Internal morphology and in situ observations on their feeding habit indicated that A. manni is a deposit feeder, feeding on organic debris contained in the sediment around its habitat. A. manni were more frequently observed near Zostrea marina bed where content of organic matter in the sediment is considered to be higher. Gonadal tissues of the male were yellow in color while female gonads appeared to be purple. Fully mature eggs, with a mean diameter of 381 $\mu$m, and sperm were observed from the histological slides of the sand dollars collected in late July to August, suggesting that A. manni spawn during July to August when water temperature reaches 20 to $25^{\circ}C$.

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Review on Risks of Perchlorate and Treatment Technologies (퍼클로레이트(Perchlorate)의 위해성과 저감기술 소개)

  • Shin, Kyung-Hee;Son, Ah-Jeong;Cha, Daniel K.;Kim, Kyoung-Woong
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.9
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    • pp.1060-1068
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    • 2007
  • Perchlorate contamination in aquatic system is a growing concern due to the human health and ecological risks associated with perchlorate exposure. In spite of potential risks associated with perchlorate, drinking water standard has not been established worldwide. Recently, US EPA has issued new protective guidance for cleaning up perchlorate contamination with a preliminary clean-up goal of 24.5 ppb. In Korea, the drinking water standard and discharge standard for perchlorate has not been established yet and little information is available to address perchlorate problems. Perchlorate treatment technologies include ion exchange, microbial reactor, carbon adsorption, composting, in situ bioremediation, permeable reactive barrier, phytoremediation, and membrane technology. The process description, capability, and advantage/disadvantages of each technology were described in detail in this review. One of recent trends in perchlorate treatment is the combination of available treatment options such as combined microbial reduction and permeable reactive burier. In this review, we provided a brief perspective on perchlorate treatment technology and to identify an efficient and cost-effective approach to manage perchlorate problem.

Spatial-Temporal Distribution Characteristics of Bigeye and Yellowfin Tunas in Kiribati Waters

  • Taanga, Aketa Mature;Cai, Yi-Hui;Lu, Hsueh-Jung;Ni, I-Hsun
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.174-179
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    • 2006
  • Information on the distribution characteristics of tuna resources in Kiribati EEZ waters in three zones (Zone 1: west Gilbert region, Zone 2: central Phoenix region, and Zone 3: east Line region) as well as their relationship with the ocean environment is critical for sustainable managing the migratory tuna resource and fishing practices in this region. Therefore, this study is designed to investigate the spatial and temporal distribution and concentration of bigeye (BET) and yellowfin tuna (YFT) in Kiribati EEZ waters in relation to sea surface temperature (SST) and thermocline depth so as to better understand the tuna resources management basis in Kiribati waters. The geographic and temporal distribution and concentration were first displayed. Paired t-test was utilized to compare the distribution between the two tuna species based on Catch per Unit Effort (CPUE) derived from the Korean longliners during 1996 to 2004, and also among the three zones of Kiribati EEZ waters. Environmental conditions of the three zones were then compared and correlated with the CPUE of YFT and BET. In addition, the effect of ENSO phenomena on the environmental conditions and the distribution of YFT and BET within the three zones were also examined. The BET was relatively higher in the Zone 3 whereas YFT predominate in the Zone 1 and the Zone 2 due to oceanographic differences among the three zones and the ecological habitats of the two tuna species. It was suggested that El Ni?o/Southern Oscillation (ENSO) phenomena altered the oceanographic conditions of the three zones that in turn change the distribution of the two tuna species. During El Ni?o, the warm phase of ENSO, resulted in having more BET in all the three zones and the opposite observed during La Ni?a (cold phase) replacing by having relatively higher catch rate for YFT, particularly in the Zone 2. Although the results of the study are from short periods (1996 to 2004) in considering oceanographic anomality, these environmental variations should be considered into sustainable fisheries management of tuna fisheries in Kiribati EEZ waters.

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Analysis of Inter-Species Association and Covariation in a Natural Deciduous Forest (천연활엽수림(天然闊葉樹林)에서의 수종간(樹種間) 상관관계(相關關係)와 공변이관계(共變異關係)의 분석(分析))

  • Kim, Ji Hong;Kuen, Kee Hyun
    • Journal of Korean Society of Forest Science
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    • v.80 no.4
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    • pp.360-368
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    • 1991
  • Utilizing chi-square test statistics, inter-species association and covariation were analyzed for the 37 woody plant species in a deciduous forest dominated by Quercus mongolica and Q. variabilis. within 50 temporarily established $20m{\times}20m$ square quadrats, the association for each pair of species was presented based on the presence-absence parameters. Acer palmatum had significant positive association with Acer mono and Kalopanax pictus, but negative association with Pinus densiflora. Other positively associated species pairs were Prunus sargentii-Macckia amurensis, Quercus serrata-Kalopanax pictus, Symplocos chinensis var. pilosa-Euonymus oxyphyllus, and Ulmus davidiana var. japonica-Lindera obtusiloba. The covariation far each pair of species was evaluated based on the quantitative measures, density and basal area. Overall results showed that the association and covariation values among species generally agreed with each other. Because covariation was calculated by density and basal area of the tallied species in the sample plots, the number of species pairs of covariation tended to be greater than those of association. Especially, Pinus densiflora, considered to be pioneer species in the successional stage, had negative covariation with most of climax species. These ecological information could be applied to silvicultural practices, such as ecosystem classification, establishment of mixed hardwood forest, and tending operations for marking crop trees and desirable species.

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Analysis of Teachers' Perceptions to Establish the Management Direction of Outdoor Space in an Elementary School (초등학교 외부공간 관리방향 설정을 위한 교사의 인식 분석)

  • Jeong, Na-Ra;Jeong, Hyun-Jeong
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.19 no.3
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    • pp.38-47
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    • 2020
  • This study analyzed the perceptions of teachers to establish the direction for managing the space outside an elementary school. Satisfaction with outdoor school spaces is influenced by the satisfaction with tree and flower plantation and outdoor rest spaces. This study found that the longer the working years of a teacher, the higher their awareness of the importance and necessity of outdoor spaces in the school. Respondents emphasized the lack of manpower and budget, as well as the indifference of the administration as hindrances to the management of outdoor spaces in the school. The outdoor space in the school should include a secure play area, plant education space, class practice spaces, and a rest area. Furthermore, the space outside the elementary school should support learning, playing, and resting. To this end, facilities such as benches, pergolas, outdoor classrooms, ecological ponds, farms, and flower beds should be provided. In an outdoor space, plants featured in textbooks, seasonal plants, and those that provide shade can be planted along with labels to provide information and thereby promote learning. The teachers expected that the management of the external space will have an educational and emotional effect on students. In response to the innovation of the school spaces, it is necessary to continuously manage the external spaces to achieve educational and emotional effects by organically connecting the outdoor spaces with the indoor space. For this purpose, it is required to provide support for securing budgets and manpower, and to introduce relevant policies.

A Study on the Sustainable Fashion Design by Organic Cotton (오가닉 코튼[Organic Cotton]을 이용한 지속가능한 패션디자인)

  • Kim, Soo-Hyun;Lee, Jae-Jung;Chung, Hyun-Sook
    • Journal of the Korean Society of Costume
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    • v.57 no.2 s.111
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    • pp.115-131
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    • 2007
  • By the turn of the century, our society has been gradually more interested in environmental problems than any other time. Ecological change spurred by industrial pollution is occurring beyond the borders of nations, and has emerged as a global issue. Such change is resulting in exhaustion of natural resources and energy, and serious climatic change. In this study, main focus regarding the process of the fashion product design system was placed on the sustainable fashion design of organic cotton as a positive and alternative suggestion. It is expected that the results of this study contribute to the fashion design planning not only for future generation but also for the present time. This study researched on brands that produced their fashion products using organic cotton. The following cases proved to possess sustainability in their product system. The results of this study can be summarized as follows: Firstly, sustainable design in organic cotton products has been a progressive ere-design in 2000s. It is mainly focus concerned with recycling and re-use of materials to protect environment. It is not chemical dependant and takes a particular care in eliminating waste water and energy in the dyeing process. It is an environmentally sustainable design better than all the other design processes. Secondly, it is a design that cares for the common good of society and the global system of fair trading. The fair trading of organic cotton products induced a change in the structure of production system, while defending human rights. It also gave benefits by promoting development in local society and progress in traditional skills. Not to mention that it contributed to building up the concept of transparency in the global economic system. Lastly, the brands emphasize their social responsibility and management ethics to observe environmental policy which is established to protect our nature and people. Their public information reminds customers of the importance of protecting the environment from diverse pollution. Moreover, they hold social events to promote public awareness for environmental Issues. This study dealt only with the organic cotton, a small subset of the subject of sustainable design. It can be extended and applied to various other sustainable fashion design as a solution for global environmental issues.

Characteristics of Marine Environment and Primary Productivity of Phytoplankton in the Seaweed Bed of Northwestern Coast of Jeju Island During Autumn 2014 (2014년 추계 제주 북서부 해조장에서 해양환경과 식물플랑크톤의 일차생산력 특성)

  • KWON, HYEONG KYU;YANG, HAN SOEB;YOON, YANG HO;CHOI, OK IN;CHOI, IM HO;OH, SEOK JIN
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.20 no.4
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    • pp.180-191
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    • 2015
  • Marine environmental characteristics and primary productivity of phytoplankton were investigated in seaweed bed of northwestern coast of Jeju Island during Autumn, 2014. The trophic state based on dissolved inorganic nitrogen and phosphorus was mesotrophic. The Redfield ratio was less than 16, indicating that nitrogen was the limiting factor for the growth of phytoplankton. Dissolved organic nitrogen and phosphorus accounts for 63 and 46% of the dissolved total nitrogen and phosphorus, respectively. Light utilization efficiency (${\alpha}$) and maximum photosynthetic capacity ($P_m{^B}$) were highest in the Donggwi (third-year marine forest), followed by Gonae (one-year marine forest), Biyangdo (natural seaweed bed) and Geumneung (whitening area). The primary productivity of phytoplankton in the Donggwi, Gonae and Biyangdo also was higher than that in the Geumneung. Although nitrogen is the limiting factor, enriched dissolved organic nitrogen might play an important role to maintain primary productivity. In addition, phytoplankton community through photosynthesis could produce about 14% of phytoplankton carbon in one hour. These results will be able to use the important information for material cycle and ecological valuation of seaweed bed.

Effect on Early Life Stage of Three Freshwater Fish (Carassius auratus, Cyprinus carpio, Oryzias latipes) Exposed to Suspended Solids (부유토사가 담수 어류 3종(붕어, 잉어, 송사리)의 초기 생활사에 미치는 영향)

  • Moon, Seong-Dae;Kang, Sin-Kil;Lee, Chang-Hoon;Sung, Chan-Gyoung;An, Kwang-Guk;Choi, Tae Seob
    • Korean Journal of Ecology and Environment
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    • v.47 no.2
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    • pp.82-90
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    • 2014
  • To assess the adverse effects of suspended solids on fishes, the hatching rate of embryo, and survival and growth of larvae were measured with common fish species of river such as crusian carp (Carassius auratus), common carp (Cyprinus carpio) and medaka (Oryzias latipes). Bioassay on hatching rate of embryo was conducted with a range of turbidity as 10 levels from 0.2 to 8,080 NTU. Another bioassay on 4-day larval survival and 21-day larval growth were also conducted with a range of turbidity as 8 levels from 0.1 to 8,260 NTU, and 6 levels from 0.7 to 2,030 NTU, respectively. The hatching rate of C. auratus was not significantly different from that of control at turbidity below 4,040 NTU, whereas it decreased when turbidity was 8,080 NTU (p<0.05). The hatching rate of C. carpio was not affected by concentration of suspended solids. For O. latipes, the hatching rate significantly decreased from 254 NTU (p<0.001) and it was zero when turbidity was 8,080 NTU. The 4-day survival of larvae of all 3 species was not affected by turbidity, while the larval growth of all 3 species was significantly affected. The turbidity effect on the growth of C. auratus and C. carpio was observed from 7 days after the exposure at turbidity level of 145, 143 NTU, respectively. The turbidity effect on the growth of O. latipes was observed from 14 days after the exposure at turbidity level of 254 NTU. The results of this study will provide the basic information for the derivation of water quality criteria on suspended solids for the protection of aquatic ecosystem and the quantitative ecological risk assessment of freshwater environment.

Potential for Application of Microhistological Analysis in Diet Plants of Korean Water Deer($Hydropotes$ $inermis$) (한국에 서식하는 고라니($Hydropotes$ $inermis$) 먹이식물의 미세조직분석법 적용 가능성 연구)

  • Kim, Eui-Kyeong;Park, Yung-Chul;Kim, Won-Myeong;Kim, Jong-Kuk
    • Korean Journal of Environment and Ecology
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    • v.26 no.2
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    • pp.192-199
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    • 2012
  • This study was to evaluate the application of microhistological analysis to collect information on food materials of korean water deer from september to October 2006. For microhistological analysis we extracted type-materials of 4 plant species ($Ipomoea$ $batatas$, $Rubus$ $coreanus$, $Glycine$ $max$, and $Pueraria$ $thunbergiana$) from fecal pellets of korean water deer ($Hydropotes$ $inermis$) and then made preparations of the fecal materials for microscopic analysis. The fecal preparations were compared with reference preparation under the microscope. In microscopic analysis of fecal preparations, we could identify the four plant species by the followings: tip shape and morphology of trichomes, epidermal cell, morphological composition and shape of stomatal apparatus, arrangement of long-cell, and distribution of crystals in cells. According to the comparisons of the preparations, the morphology of trichome, epidermal cell and stomata are similar between both preparations of the fecal pellets and the references, respectively. This methodology will contribute to understanding feeding behavior and behavioural ecology by climate change of other hervibores as well as korean water deers.

Agroforestry Strategies Reflecting Residents' Attitudes in a Semi-arid Region - Focusing on Elsentasarhai Region in Mongolia - (주민의식을 반영한 반건조지역의 산림농업 전략 - 몽골 엘센타사라이 지역을 중심으로 -)

  • Jo, Hyun-Kil;Park, Hye-Mi;Kim, Jin-Young
    • Korean Journal of Environment and Ecology
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    • v.28 no.2
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    • pp.263-269
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    • 2014
  • This study explored agroforestry strategies to achieve ecological and economic effects simultaneously for Elsentasarhai region in Mongolia under desertification, based on attitude survey with a questionnaire, field survey on planting sites, and literature review. The agrosilvopastoral approach was suggested as a type of agroforestry practices which combined tree planting for combatting desertification and wind damage to crops, agricultural crop production for income improvement, and livestock raising, a major industry in the study region. Populus sibirica and Ulmus pumila native to desert regions were selected for tree planting, and Hippophae rhamnoides, potato, and fodder appropriate for the short growing season were chosen for income crop production, reflecting residents' attitudes and growth environments. As a strategy of land allocation to satisfy multiple effects of the agrosilvopastoral approach, the alley cropping technique was recommended which arranged alternately strips of trees as windbreaks and income crops in multiple rows. The study also explored desirable planting techniques to improve conditions of income crop production and tree growth against drought and strong winds in the alley cropping. Study results will be useful as fundamental information to implement sustainable agroforestry in Mongolia and other semi-arid regions where knowledge concerned is lacking.