• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.3
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• pp.69-76
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• 2017

Eelgrass, Zostera marina is a marine flowering plant that grows in submerged habitats for most of its lifetime, and experiences desiccation stress when exposed to air. Although the desiccation stress observed in adult eelgrass has been frequently studied, there has been little research on desiccation stress in eelgrass seeds. To survey desiccation stress in eelgrass seeds, we studied the germination rate and moisture content upon desiccation caused by exposure to air. The germination rate of the eelgrass seeds exposed to air for 1 hour at $20^{\circ}C$ and 50% relative humidity decreased markedly, and it decreased consistently as the exposure time increased. Eelgrass seeds exposed to air for longer than 11 hours did not germinate. As the exposure time of eelgrass seeds to air increased, the germination rate and moisture content decreased, showing a negative correlation. In addition, eelgrass seeds exposed to air at $30^{\circ}C$ showed significantly lower germination rates than those exposed to air at $10^{\circ}C$ or $20^{\circ}C$. Our results revealed that desiccation causes a decrease in the germination of eelgrass seeds, which will provide useful information for eelgrass habitat restoration using seeds.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.5
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• pp.681-691
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• 2022

Zostera marina (ZM), a type of seagrass registered as a marine protected species in South Korea, provides valuable ecosystem services to humans, such as improving marine water quality, providing food, spawning grounds and habitats for marine life, and absorbing carbon dioxide. Therefore, the government is seeking to preserve ZM by designating ZM-protected areas. This study examined the public willingness to pay (WTP) for the preservation of ZM using contingent valuation. The one-and-one-half-bounded model was adopted for WTP elicitation, and the single-bounded model was also applied for comparison. The spike model was employed to deal with many zero WTP responses. The household average WTP was estimated as KRW 4,087 per year, securing statistical significance. The national value was KRW 84.1 billion per year. The preservation value of ZM estimated in this study can be used as important data for economic analysis of various projects or policy implementation for its preservation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.1
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• pp.41-47
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• 2009

Since significant losses of seagrass coverage have been reported from many parts of the world, numerous restoration projects through seagrass transplantation have been attempted worldwide. Different survival rates and establishment time of transplants have been reported depending on transplanting time and methods. The staple method, which is direct seagrass planting method using staples to anchor seagrass transplants on the sediments, have been widely adopted in seagrass transplanting because this method achieves high survival rates in various sediment environments. To assess the morphological plasticity and the growth characteristics of transplants, we transplanted eelgrass, Zostera marina in December 2004 using the staple method. Shoot density, morphological characteristics and leaf productivities of the transplanted shoots and shoots of natural eelgrass beds in the vicinity of the transplanting site and environmental parameters in the planting site were monitored for about 1 year postplanting monthly. Transplant shoot density increased without initial decline, while leaf width and sheath length of transplants decreased after transplanting. Leaf productivities per shoot of transplants also considerably lower than those of natural shoots for the first 3 months post-transplanting. Shoot density, morphological characteristics and leaf productivity per area of transplants became similar to those of natural population about 1 year after transplanting. Although eelgrass transplants might have experienced some transplanting stress during the early stage of the transplantation, transplants appeared to adapt well to new environments of the transplanting site.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.236-237
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• 2002

해초생태계는 해초 잎 및 지하경, 그리고 뿌리등 해초와 직간접적으로 영향을 주고 받을 수 있는 여러 생물들: 조류와 무척추동물, 해초지를 산란장이나 생육장으로 삼고 있는 어류, 그리고, 식물 및 동물 플랑크톤 등으로 구성되어 있다. 이 중 부착조류는 해초생태계 내에서 생산성의 가장 중요한 요소일 뿐만이 아니라, 종 다양성을 증가시키며, 무척추동물의 먹이 공급의 기본적 요소이다 (McRoy and Helfferich, 1977; Coleman and Burkholder, 1995). (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.211-212
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• 2002

해초에 서식하는 부착생물의 생태학적인 이해를 위해 수주의 물리 화학적 요인 (수온, 염분, 영양염의 농도)이 잘피와 부착생물 및 부착조류의 성장에 미치는 영향을 알아보고자 하였다. 영양염의 농도 중 특히 질산염은 해양 수주 내에 부족할 경우 식물 플랑크톤을 비롯한 광합성 식물의 성장을 방해하는 요인으로 잘 알려져 있으며 (예, Bougis, 1976), 질산염이 부착생물에 미치는 영향에 대한 많은 연구가 수행되었다(Williams and Ruckelshaus, 1993, Coleman and Burkholde.,1994, 1995). (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.277-278
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• 2003

The Korean populations of Z. marina are typically distributed in patches. Although molecular and biochemical approaches are now increasingly being applied to address the taxonomic and phylogenetic relationships within the animals, plants, and other algal species in Korea (Huh 1998; Hwang et at. 1998; Huh 2001), no population genetic studies of this species have been conducted. (omitted)

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.339-348
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• 2012

To survey the seagrass distribution in Jeju and Chuja Islands, we directly observed seagrass beds using SCUBA in July, 2011. Distributional area, species composition, morphology, density, and biomass of seagrasses and environmental characteristics were examined in investigation sites. In particular, three protected seagrass species (Zostera marina, Z. caulescens and Z. caespitosa) were found in the investigation areas. While the three species were found in Chuja Island, only Z. marina was distributed in Jeju Island. Z. marina was distributed only north-eastern coast of Jeju Island, and the total coverage was $238,572m^2$. Total seagrass coverage of Chuja Island was $23,584m^2$. In detail, Z. caulescens Z. caespitosa and Z. marina were 21,216, 1,870 and $498m^2$, respectively. Of these, Z. marina was found from the intertidal to subtidal zones of 5m MSL (mean sea level) depth. Z. caespitosa and Z. caulescens were found in subtidal zones of 3~4 m and 4~6m MSL depth, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.532-542
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• 1997

Seasonal variation of a shrimp community in the eelgrass (Zostera marina) bed in Kwangyang Bay, Korea was studied based on the monthly collected samples through a year of 1994. The shrimp community in the eelgrassbed was composed of 26 species of shrimps representing 6 families. The community was dominated by Heptacarpus pandaloides, Crangon affinis, Eualus leptognathus, Latreutes acicularis, Heptacarpus rectirostris, Heptacarpus geniculatus, and Latreutes laminirostris. Most of species were the small-sized species with carapace length smaller than 25 mm. The peak abundance occurred in the late winter and spring and low abundances in autumn. More than 10 species were collected every month except lull (8 species). Species diversity indices showed that the shrimp species were more diverse during the late summer, and lesser during the late autumn. Predominance of Crangon affinis in the late autumn caused such a low diversity. The shrimps in the study area could be grouped into three groups on the basis of their occurrence patterns: resident species, seasonal species, and temporary species. More abundant and more diverse shrimps were collected during nighttime than daytime.

• The Journal of the Acoustical Society of Korea
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• v.23 no.8
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• pp.562-569
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• 2004

An experiment for observation of the distribution of the seagrass (zostera marina) beds and characteristics of high-frequency backscattering by the photosynthesis was conducted off the coast. Acoustic data were taken as a function of the grazing angles and the relative azimuth angles on the seagrass beds of which bottom type was sandy-mud. The transmitted source signal was a 120 kHz CW waveform. Mapping of the seagrass beds distribution was drawn up using the seagrass backscattering strength with azimuth and grazing angles. The result of the comparison backscattering strength distribution of the seagrass beds was shown to be the similar to the photograph of real seagrass beds. The seagrass backscattering strength was also compared between day and night to verify the effects of the acoustical scattering by the bubbles of Photosynthetic oxygen formed on the seagrass. In these results. it is clear that observation of the seagrass beds between day and night showed the different characteristics because the bubbles of Photosynthetic oxygen affect the acoustical scattering.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.744-752
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• 1997

A total of 60 species of benthic macrofauna was collected by a grab sampler in the eelgrass bed in Kwangyang Bay, Korea. The dominant group was Polychaeta which was composed of 32 species. The dominant species were Platynereis bicanaliculata, Cirriformia tentaculata, Lumbrineris longifolia, and Cirratulus cirratus which accounted for approximately $63.7\%$ of the total numbers of benthic macrofauna. Seasonal variations in both species composition and abundance of the benthic macrofauna were major characteristics in the study area. Seasonal peak of number of species and abundance occurred in summer. And the lowest abundance occurred in winter. Seasonal dominant species were Platynereis bicanaliculata, Cirriformia tentaculata, Lumbrineris longifolia in spring and summer, and Cirratulus cirratus, Capitella capitata, Opisthobranchia in fall.