• Title/Summary/Keyword: rocky

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Community Dynamics of Benthic Marine Algae in the Intertidal and Subtidal Rocky Shore of Samyang, Jejudo Island

  • Yoo,Jong-Su
    • ALGAE
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    • v.18 no.4
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    • pp.301-309
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    • 2003
  • Community structure and vertical distribution of benthic marine algae were investigated in the intertidal and subtidal rocky shore of Samyang, Jejudo Island. The total number of 62 algal species composed of 6 Cyanophyta, 6 Chlorophyta, 19 Phaeophyta, and 31 Rhodophyta were observed. The dominant species were melobesioidean algae, Sargassum thunbergii, Hizikia fusiformis, and Ulva pertusa in the intertidal zone and melobesioidean algae, Ulva pertusa, Corallina spp., and Undaria pinnatifida in the subtidal zone. The vertical algal distribution was represented by the melobesioidean algae in the whole rocky shore, Caulacanthus ustulatus in the upper intertidal zone, Sargassum thunbergii and Hizikia fusiformis in the middle and lower zone, Ulva pertusa in the lower zone and Ulva pertusa, Corallina spp., and Undaria prinnatifida in the subtidal zone. The composition of dominant species and pattern of the vertical distribution of algae in the present study were significantly different from the previous reports. Especially, distribution of crustose coralline algae was significantly extended.

Biomechanical Application of Plantar Pressure Distribution for Walking on Uneven Rocky Surface (Uneven Rocky Surface 이동 시 압력분포를 적용한 운동역학적 활용)

  • Chung, Yong-Min
    • Korean Journal of Applied Biomechanics
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    • v.19 no.2
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    • pp.387-397
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    • 2009
  • Physical activity has been increased with increased leasure time. Specifically, due to our mountainous geographical benefits, people actively participate in hiking and climbing as regular daily activities. Thus, more stable and comfortable hiking boots are required to walk on uneven and sloped rocky surface for a long period of time. 5 male subjects were recruited for testing planter pressure patterns of four different conditions(barefoot, classic hiking boot, stiffness 60 and stiffness 65). Tested hiking boots(stiffness 60 and stiffness 65) consists of the multiple pieces of outsoles as they are designed for a better shock absorption. In the results, some positive aspects of stiffness 60 and stiffness 65 such as wide contact area and powerful propulsive patterns at take off was observed compared to the classic hiking boots. Therefore, biomechanical development of hiking related clothes and footwear as well as equipment would be beneficial for people who enjoy hiking to maximize their quality of activities.

An analysis on vegetation characteristics of the rocky slopes in expressway according to the type of greening works (녹화공법에 따른 고속도로 암반비탈면의 식생 특성 분석)

  • Lee, Su Ho;Jeon, Gi-Seong;Lee, Jeman;Kim, Kyung-Hoon;Kim, Dongyeob;Im, Sangjun;Park, Yeong Dae
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.26 no.1
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    • pp.1-16
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    • 2023
  • The current study aims to analyze the vegetation characteristics of the rocky slopes in expressway applied by different types of greening work. A field survey on the current status of vegetation were conducted in 50 rock slopes along 13 expressways in two years, 2020 to 2021. Specifically, the type of implemented greening and slope stabilization work, the soil properties, the vegetation coverage, and the emerged species were investigated on a every single slope. As the result of the implemented work types, the soil-media hydroseeding and the gabion work appeared to be the most implemented greening and slope stabilization work, respectively. As a result of the vegetation survey, 126 classification groups (42 families, 93 genera and 126 species) were identified in total and it was observed 26 IAP species and 5 invasive species were growing. The longer the time after greening work, the more frequent appearance of IAP species were observed. Woody species such as Robinia pseudoacacia and Lespedeza bicolo, and perennial herbs such as Artemisia princeps, Erigeron annuus, and Festuca arundinacea were appeared with high frequencies at the rocky slopes in expressway. It was also observed Pinus densiflora, Quercus dentata, Rubus crataegifolius and Miscanthus sinensis which had invaded from the adjacent forests naturally, and the largest number of species were invaded between 5~10 years usually after greening work in this study.

Species-specific biomass drives macroalgal benthic primary production on temperate rocky reefs

  • Spector, Michael;Edwards, Matthew S.
    • ALGAE
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    • v.35 no.3
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    • pp.237-252
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    • 2020
  • Temperate rocky reefs dominated by the giant kelp, Macrocystis pyrifera, support diverse assemblages of benthic macroalgae that provide a suite of ecosystem services, including high rates of primary production in aquatic ecosystems. These forests and the benthic macroalgae that inhabit them are facing both short-term losses and long-term declines throughout much of their range in the eastern Pacific Ocean. Here, we quantified patterns of benthic macroalgal biomass and irradiance on rocky reefs that had intact kelp forests and nearby reefs where the benthic macroalgae had been lost due to deforestation at three sites along the California, USA and Baja California, MEX coasts during the springs and summers of 2017 and 2018. We then modeled how the loss of macroalgae from these reefs impacted net benthic productivity using species-specific, mass-dependent rates of photosynthesis and respiration that we measured in the laboratory. Our results show that the macroalgal assemblages at these sites were dominated by a few species of stipitate kelps and fleshy red algae whose relative abundances were spatially and temporally variable, and which exhibited variable rates of photosynthesis and respiration. Together, our model estimates that the dominant macroalgae on these reefs contribute 15 to 4,300 mg C m-2 d-1 to net benthic primary production, and that this is driven primarily by a few dominant taxa that have large biomasses and high rates of photosynthesis and / or respiration. Consequently, we propose that the loss of these macroalgae results in the loss of an important contribution to primary production and overall ecosystem function.

The Effect of Substrate on Ecophysiological Characteristics of Green Macroalga Ulva pertusa Kjellman (Chlorophyta) (구멍갈파래(Ulva pertusa Kjellman)의 생태생리에 대한 생육기질의 효과)

  • Choi, Tae-Seob;Kim, Kwang-Young
    • ALGAE
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    • v.20 no.4
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    • pp.369-377
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    • 2005
  • Seashore joining with land and sea, which is typical habitat for marine macroalgae, is classified two types of shore as soft- and hard-bottom shore according to topographical (geological) and ecological features. We compared two of Ulva pertusa Kjellman from two contrasting habitats, sandy (soft-bottom, Haenam) and rocky shore (hard-bottom, Hadong) in terms of chlorophyll-a fluorescence and its parameters, and various photosynthetic pigment and nutrient content in the tissue of those. Both of habitats were different in the light environment such as light attenuation coefficient and even in nutrient concentration of ambient seawater. Electron transport rate (ETR) of Ulva from sandy shore was higher than from rocky shore. The range of photosynthetic pigment content in the tissue of U. pertusa was significantly much more in from sandy shore, and also nitrogen and phosphorus content were significantly higher except for carbon content. However, there were no significant differences in the ratio of among photosynthetic pigments, and N:P ratio was similar between each other, even though significantly different. Our result implied on the reason of why most of green tides in the worldwide concentrated and frequently occurred at sites with sandy, muddy and silty bottoms, being classified as soft-bottom shore.

Ecological Study on the Intertidal Zone around Cheju Island 1. Estimation of Plankton Production and Community Structure of Marine Shells - Community Structure of Molluscan Shells (제주도 조간대의 생태학적 기초연구 1. 플랑크톤에 의한 생산량추정 및 패류의 군집구조-패류의 군집구성)

  • 이정재;좌용우
    • The Korean Journal of Malacology
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    • v.4 no.1
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    • pp.17-29
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    • 1988
  • The study had been carried out three times, from April 1987 for the purpose of analysis on the community structure and the distribution patterns of the Molluscan shells at the intertidal zone of Cheju Island. 1) The Molluscan shells collected and identified at all studied sites were composed of 3 classes, 10 orders, 23 families and 42 species.2) In all studied sites, individual numbers according to species were Nodilittorina exigua, Monodonta neritoides, Lunella coronata coreensis, Heminerita japonica in order. On the other hand, the dominant species of the rocky sits were N. exigua, M. neritoides and the rocky and silty-sand sites was Batillaris multiformis.3) In the vertical zonation, in the supralitorial zone, N. exigua was dominant species and the wpper-tidal zone, N. exigua, H. japonica and B. Multiformis were dominant species, but B. multiformis was dominant in the rocky and silty sand sites. In the middle tidal zone, M. neritodes, H. japonica, L. coronata coreensis were dominant and in the lower tidal zond, M. neritodes, L. coronata coreensis, Liolophura japonica were dominant.4)In the analysis on community of Molluscan shells, Chagwi, Pyoson an dAewol sites were more diverse than other sites in the species diversity and environmental inhibits were also favorable.5) Community similarities among the studied sites based on the similarities values were divided into two groups according to the difference of the ground: Hagwi, Chongdal and Sehwa sites group and the others sites group.

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Winter Biomass of Ulva Mats in a Rocky Intertidal Zone of the Southern Coast of Korea (겨울철 암반 조간대에서 갈파래 (Ulva species) 매트의 생물량)

  • 최태섭;최종관;박승민;김정하;김광용
    • Korean Journal of Environmental Biology
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    • v.19 no.1
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    • pp.37-42
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    • 2001
  • The biomass of Ulva mats was surveyed in a lower rocky shore of the southern coast of Korea during the 1998-1999 winter. The population selected for the present study was located on the tidal zone ranging from 118 cm to 130 cm below mean sea level (MSL), where abundance of Ulvu species was highest. The biomass of Ulva species increased gradually from December 1998 until February 1999, reaching the maximum of 374 g dry wtㆍm$^{-2}$ in February. The biomass varied little among the sampling quadrats for each sampling time. Over the course of the study a total of 16 taxa were sampled from Ulva mats, of which 5 were macrophytes and 11 were macroinvertebrates. Rodophyta comprised 3 taxa, followed by Phaeophyta of 2 taxa, but there was no Chlorophyta except for Ulva species. The macrofaunal assemblage was consisted of 8 taxa of Mollusca, 2 Arthropoda and 1 Annelida. There was a dramatic increase in Mytilus sp. in February. Moreover, the trend of biomass were similar between some macroinvertebrates and Ulva species. The results suggested that macroinvertebrates may play an important role in nutrient dynamics as well as food web. Further experimental evidence may be necessary to explain the correlation between Ulva mats and abundance of coexisting macroinvertebrates.

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A Study on Effects of Artificial Structures on Bryophyte Diversity in Urban Greenery

  • Yoshitaka Ohishi;Ukihiro Morimoto
    • Journal of the Korean Institute of Landscape Architecture International Edition
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    • no.2
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    • pp.109-113
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    • 2004
  • It is important to consider urban parks and greenery not only from the viewpoint of amenity or aesthetics but also from the viewpoint of biodiversity. In this study, we focused on bryophytes (mosses), and analyzed how existence of artificial structures in urban greeney, such as concrete curbs and stone walls, affect species diversity of bryophytes. Kyoto Gyoen in Kyoto City, western Japan, was selected as the study site. In consideration of kinds of substrates on which bryophytes grow, microhabitats of Kyoto Gyoen were divided into ten types including concrete curbs and stone walls. In each type of microhabitats, we selected the area where bryophyte diversity was highest, and established a quadrat for bryophyte flora survey. Our results showed that the number of bryophyte species and growth forms and the value of diversity indices on concrete curbs or stone walls were higher than the averages of those. The bryophyte species were divided into the four groups by TWINSPAN as follows: Group A (epiphyte species), Group B (rocky species), Group C (roadsides, grassland or forest species), and Group D (waterside species). Bryophytes classified into Group B (rocky species) were mainly recorded on concrete curbs or stone walls. It was considered that the existence of artificial structures (concrete curbs and stone walls) provided favorite habitats for the bryophytes classified into Group B (rocky species), which mainly grows on concrete or rocks, and enhanced species diversity of bryophytes in Kyoto Gyoen.

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Macrobenthos Assemblages on the Rocky Shores of Wando and Jodo islands in Dadohaehaesang National Park in Summer (다도해해상국립공원 완도·조도 암반조간대 하계에 출현한 대형저서무척추동물)

  • Lee, Changil;Yang, Sehee;Gang, Sunhwa;Seo, Chonghyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.843-852
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    • 2022
  • To determine the composition of benthic species on the southwest coast, a macrobenthos study was conducted at 18 sites on the islands of Wando and Jodo for seven summers (2014-2021) from June to September. Two hundred and twenty species(645 ind./m2) were collected on the rocky shores of Wando and Jodo. A similar number of species was observed in Wando (165 species) and Jodo (167 species). The mean density was higher in Wando (726 ind./m2) than in Jodo (564 ind./m2). The number of species was the highest at Site 15 (116 species), and the density was highest at Site 7 (1,664 ind/m2). The dominant species were Nodilittorina radiata with 175 ind./m2 (27.1%), Littorina brevicula with 97 ind./m2 (15.1%), and Heminerita japonica with 41 ind./m2 (6.3%). The climate change indicator species, Tetraclita japonca, appeared in 15 sites, and the endemic species, Ptilohyale bisaeta, appeared in some sites. Fusinus spectrum, which appears on the Red List as a Near Threatened (NT) species, the lowest level of extinction risk, appeared in Jodo. The macrobenthos of Wando and Jodo demonstrated the general characteristics of rocky shores in Korea. Based on the tides and substrate, the rocky shores revealed a vertical distribution trend where Nodilittorina radiata, Littorina brevicula, Chthamalus challengeri, and Reishia clavigera were dominant. Wando and Jodo exhibited similar habitat distribution patterns.