• The Korean Journal of Ecology
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• 제18권4호
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• pp.493-502
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• 1995

Nodulation phenology in relation to plant phenology, vertical distribution of nodul and root biomass in different soil, correlation between nodule and root size, and nitrogen mineralization around the rhizosphere by ion-exchange resin bag buried at 10 cm of soil were studied in Elaeagnus nmbellata (autumn-olive) stand, Korea. Nodulation appeared from spring to autumn and nodule phenology was coincided with the timing of root activity rather than that of foliation. Nodul size increased in proportion to the root size. In the sand dune with the lower root biomass, nodule appeared up to 80 cm deep in soil and the nodule biomass was 1,070 kg/ha, which was the highest value reported for several actinorhizal plants in the temperate regions. It is suggested that nodule distribution and production are mainly influenced by soil aeration among environmental factors. The higher ammonification or lower nitrification rate contrasted markedly with the earlier studies that reported lower ammonification or higher nitrification in actinorhizal plant soil. Nitrogen mineralization rate around the rhizosphere with root and nodule was characterized by higher nitrification rate than that in the control soil without root and nodule.

• The Korean Journal of Ecology
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• 제6권3호
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• pp.167-176
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• 1983

Species composition, life form, biomass and soil properties of the halophyte communities were investigated from July to September, 1982. At the reclaimed land of Sanho-ri, sand dune of Jido, salt marsh of Suncheon Bay, and Somjin River estuary of Baealdo, species numbers were 26, 14, 13 and 7, dominant species were Salicornia herbaceae, Carex pumila and Suaeda japonica, respectively. Species composition of the 4 investigated areas was 13 families, 25 genera and 39 species, and of them, 10 families, 21 genera and 24 species were attributed to halophytes. Out of 22 life forms, the representative for Jido was $ G-D_4-R_1-3-e.t$and those for the other sites were Th-G4-R5-e. Above ground biomass of all species for Sanho-ri, Jido, Suncheon Bay and Baealdo were 441.3, 202.0, 150.7 and 353.3 g.dw/m2 and the ratios of above ground biomass halophytes to all species were 93.5, 92.7, 90.8 and 100%, respectively. The leading dominant species formed a continuum according to the salt gradiant. The similarity between Baealo and Suncheon Bay was relatively high, and Jido was quite different from the others in species composition. Aster tripolium was stenohaline and appeared at the low salt concentration, but Suaeda maritima and Suaeda asparagoides were duryhaline and occured at the relatively high salt concentration.

• 한국환경복원기술학회지
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• 제21권3호
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• pp.83-98
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• 2018

This study was conducted on rare plants distributed in Chungnam area from April, 2012 to November, 2017. The rare plant populations that are emerging are: Utricularia pilosa, Jeffersonia dubia, Iris ruthenica, Tipularia japonica, Calanthe discolor, Parasenecio pseudotaimingasa, Ranunculus kazusensis, Berchemia racemosa, Pogonia minor and Glehnia littoralis. According to the criteria of the International Union for Conservation of Nature (IUCN), plant resources in the rare species category were one important type (CR), three hazardous species (EN) and six vulnerable species (VU). As a result of analyzing characteristics of ecological environment and threats, five types of habitat types, two aquatic areas, two types of flatland and coastal sand dune distribution types were analyzed. The decreasing tendency of the rare plant populations in the surveyed area is judged to be artificial disturbance and habitat destruction rather than climate or environmental change. Considering the characteristics of habitat, conservation measures should be prepared for each population.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.445-448
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• 2006

Mix design of C80A which is applied to the vertical members of The Burj Dubai Tower, the tallest building of the world, was performed so as to meet the requirements of rheological property, mechanical properties & construction sequences based on material analysis in Dubai, UAE. Experimental investigations were carried out to evaluate & optimize the quantities of total binders, the proportions of Micro Silica, Dune Sand & PFA, changes of S/a and the comparison of chemical admixture, etc. Approximately $65,000m^3$ of C80A concrete has been poured to the vertical members since 16-Apr-2006. In the actual application, it was showed that C80A has proper early strength achievement, excellent mechanical properties and satisfactory flowability & workability. The results of extensive site testing can be summarized that the average compressive strength at 28days is 98.8MPa, the average elastic modulus at 28days is 47.8GPa, the flow of concrete after pumping at the height of 250m (L72) was over 500mm.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.763-766
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• 2008

우리나라의 해안사구에 위치하고 있는 해안방재림의 실태를 파악한 결과, 신규 조성대상지는 576개소 250.05ha로 개소당 평균 면적이 약 0.43ha인 것으로 나타났다. 따라서 현재의 신규 조성대상지 개소당 기준인 1ha는 조정할 필요가 있으며, 특히 연간 조성사업량인 10ha/년에 의하면 사업이 종료되기까지 약 25년이 소요되므로 5년 이내에 사업이 완료될 수 있도록 사업을 확대해야 하며, 이에 필요한 사업비 확보가 시급히 이루어져야 할 것이다.

• 한국식품위생안전성학회지
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• 제29권4호
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• pp.356-362
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• 2014

Allergic diseases have increased rapidly over the past decades, affecting an estimated 20~30% of the population in developed countries. In this study, we investigated whether or not a typical costal sand dune plant Carex pumila (CPE) suppresses the activation of mast cells and IgE-mediated allergic response in vitro and in vivo. As the results, the extract of Carex pumila inhibited antigen-stimulated degranulation in RBL-2H3 cells and Bone marrow-derived mast cells (BMMCs), and IgE-mediated passive cutaneous anaphylaxis (PCA) in mice. CPE also suppressed the production of pro-inflammatory cytokines, TNF-${\alpha}$ and IL-4, in antigen-stimulated mast cells. As its mechanism of action, CPE inhibited the activation of Syk in $Fc{\varepsilon}RI$-mediated signalling pathway, and that of LAT, a downstream adaptor molecule of Syk, in a dose-dependent manner. CPE also suppressed the activation of mitogen-activated protein (MAP) kinases, p38, ERK1/2, JNK, and Akt. Altogether, CPE inhibited mast cell activation and IgE-mediated allergic response by antigen through suppressing the activation of Syk. These results suggest that CPE may be useful for the treatment of allergic diseases.

• 한국지형학회지
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• 제23권3호
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• pp.93-104
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• 2016

High school textbooks of world geography show geomorphic featuresin arid environments such as sand dune, yardang and ventifact which are largely created by aeolian processes. Desert pavements, ubiquitous armored surfaces composed of a mosaic of clasts in hot and arid regions, are introduced as a major landform which can be attributed to wind erosion. However, they are formed by a variety of processes including deflation, surface runoff, upward clast migration and dust accretion that cause coarse particles concentration at the surface. The deflation by wind leaving a lag of coarse clasts has been solely regarded at home, even though the classical mechanism of deflation has been evaluated as a relatively unimportant process of pavement formation abroad through empiricalstudies. The accretionary model is gaining wider acceptance, thus implying that desert pavements could be formed through deposition of aeolian material. In addition, sheetflood and upward migration of clasts, irrelevant to the aeolian processes, could also create stone pavements. As a consequence, the deflation process in high school textbooks has to be urgently modified into a range of processes including aeolian mantling. By stressing that desert pavements are an exceptional geomorphic feature in deserts where wind is a predominant geomorphic agent, they can be used as a good example to demonstrate that a landform is not monogenetic.

• 한국지형학회지
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• 제27권1호
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• pp.21-31
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• 2020

Planting pine trees on the coastal dunes has been carried out along the East coast as well as West coast of South Korea. Although the artificial forestation has been regarded as a good policy that help to protect the coastal area from natural disasters, but its real effect to the landscapes is still unknown. In this study, we have installed a monitoring site with an automated weather station to study requirements for dune formation and its environmental changes in Osan beach, Yangyang-Gun, Gangwon Province. We analyzed the meteorological data collected from 2010 to 2019 and vegetational changes in the study area. As a result, the wind speed is decreased by around 30% and the pine-covered area is increased by around 300m² after planting Japanese Black Pine in 2015. At present, it seems that the eolian transport of sand particle is minimal, because the dominant winds are the westerly winds which is not landward but seaward, and because the surface roughness length is about 0.5m which is similar to that in the deciduous forest.

• 한국토양비료학회지
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• 제35권3호
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• pp.137-144
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• 2002

우리나라 동남부 해안지대에 분포되어 있는 영일토양의 모재와 생성학적(生成學的) 특성을 파악하여 토양분류체계의 보안과 합리적 토지이용 및 관리를 위한 기초자료를 얻고자 경북 영일군에 분포된 대표 토양의 이화학성과 분포실태를 조사 분석한 결과는 다음과 같다. 영일토양은 경북 영일군과 울진군의 일부 해안지대 해안 50m이하 구릉지에 376 ha가 분포되어 있고 이들 대부분은 밭으로 이용되고 있었다. 대표단면의 전층(全層)은 사질계(砂質系)에 속하였으며 40~100cm부위는 점토함량(粘土含量)이 30%내외로 높았다. 모래의 입경별 분포는 조사립(粗砂粒)이 적은 반면, 0.5~0.1mm크기의 중간모래(중사(中砂))가 대부분이었으며, 중사(MS)/전체모래(TS)의 비가 높아 최고 0.76에 달하였으나 C층은 0.49로 낮았다. 중사(MS) 중의 중광물(重鑛物) 함량은 1.0-6.6%로 낮았고 전층을 통하여 사장석(斜長石)의 비가 정장석(正長石)에 비해 높았으며, 석영(石英)과 장석(長石)의 비는 0.7~1.8로 표토에서 높은 경향이었다. 영일통 대표단면 모래의 입도(粒度) 누적곡선(累積曲線)은 사암 유래 잔적토(殘積土)보다 잘 분급(分級)(well sorted)되어 있어 사구토양(해리통)과 유사하였고 토심 40cm 이하부터는 더 오래된 풍적퇴적물(風積堆積物)로 된 Bisequm단면이었다.

• 한국미생물·생명공학회지
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• 제40권3호
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• pp.261-267
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• 2012

본 연구에서는 경기도 궁평항 지역의 해안사구에 서식하고 있는 토착식물 6종(Rorippa islandica, Rumex crispus, Artemisia princeps var. orientalis, Lilium sp Stellaria media, and Gramineae)의 식물 뿌리와 근권토양으로부터 colony library를 구축하여 식물성장촉진 능력과 내염능을 평가하였다. 분리한 근권세균 중 4.0%의 염분이 존재하는 환경에서 50% 이상의 세균이 염분에 강한 내성을 가지고 있었다. 95개의 균주를 대상으로 식물성호르몬인 IAA생산능을 가지는 균주는 근권토양에서는 13.9%, 식물뿌리에서는 7.6%였으며, 1-aminocyclopropane-1-carboxylic acid (ACC)를 제거하는 ACC deaminase 활성을 가진 균주는 근권토양에서는 55.8%, 뿌리에서는 36.6%였다. 또한, Siderphores 합성능을 가지고 있는 균주는 근권에서 62.7%, 뿌리에서는 50%를 차지하였다. 식물성장촉진능과 내염능을 가진 세균을 대상으로 상관관계를 분석한 결과, ACC deaminase 활성과 siderphore(s) 합성능 사이에는 양의 상관관계를 형성하였고(r=0.605, p<0.037), 염분 내성능과 ACC deaminase 활성, 염분 내성능과 siderphore(s) 합성능 사이에도 양의 상관관계를 형성하였다(r=0.762, p<0.004, r=0.771, p<0.003, 각각).