• 한국작물학회지
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• 제28권3호
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• pp.310-318
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• 1983

본 시험은 식생분석법(vegetation analysis)에 많이 이용되는 4가지 분석방법 즉, List quadrat 방법, Clip quadrat방법, Point quadrat방법, Line intercept방법을 비교 분석하였다. 1. 분석 방법별로 얻어지는 초종수에 있어서는 List quadrat방법이 14종으로 가장 많았고, Line intercept방법이 8종으로 가장 적었다. 한편 Clip quadrat방법과 Point quadrat방법은 다같이 12종씩 기록되었다. 2. Clip quadrat방법은 여뀌바늘(Ludwigia prostrata Roxb), 벗풀(Sagittaria trifolia L.)등과 같이 수분함량이 비교적 적은 초종에 대해서는 지나치게 높은 우점도(Importance value)를 보이는 경향이며 반면 올미(Sagittaria Pygmaea Miq.) 또는 물달개비〔Monochoria vaginalis(Burm. f)〕와 같은 수분함량이 높은 초종에 대해서는 지나치게 낮게 우점도를 나타내는 경향이었다. 한편 Line intercept 방법은 벗풀(S. trifolia)와 가래(Potamogeton distinctus Benn.)등과 같이 넓은 잎을 가진 초종에 대해 높은 우점도를 나타내는 경향이었다. 3. 본 시험에 사용된 4가지 방법중에서 어느 방법을 선택하더라도 별다른 큰 문제점을 야기 시키지는 않았으나 작업과정중의 노력절감, 시간절약 또는 우점초종의 초종수 및 우점순위 등을 종합적으로 볼 때 Point quadrat방법이 가장 바람직하였고, Line intercept방법이 가장 바람직하지 못하였다.

• Journal of Ecology and Environment
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• 제41권8호
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• pp.223-234
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• 2017

Background: Spatial structure of plants in a population reflects complex interactions of ecological and evolutionary processes. For dioecious plants, differences in reproduction cost between sexes and sizes might affect their spatial distribution. Abiotic heterogeneity may also affect adaptation activities, and result in a unique spatial structure of the population. Thus, we examined sex- and size-related spatial distributions of old-growth forest of dioecious tree Torreya nucifera in extremely heterogeneous Gotjawal terrain of Jeju Island, South Korea. Methods: We generated a database of location, sex, and size (DBH) of T. nucifera trees for each quadrat ($160{\times}300m$) in each of the three sites previously defined (quadrat A, B, C in Site I, II, and III, respectively). T. nucifera trees were categorized into eight groups based on sex (males vs. females), size (small vs. large trees), and sex by size (small vs. large males, and small vs. large females) for spatial point pattern analysis. Univariate and bivariate spatial analyses were conducted. Results: Univariate spatial analysis showed that spatial patterns of T. nucifera trees differed among the three quadrats. In quadrat A, individual trees showed random distribution at all scales regardless of sex and size groups. When assessing univariate patterns for sex by size groups in quadrat B, small males and small females were distributed randomly at all scales whereas large males and large females were clumped. All groups in quadrat C were clustered at short distances but the pattern changed as distance was increased. Bivariate spatial analyses testing the association between sex and size groups showed that spatial segregation occurred only in quadrat C. Males and females were spatially independent at all scales. However, after controlling for size, males and females were spatially separated. Conclusions: Diverse spatial patterns of T. nucifera trees across the three sites within the Torreya Forest imply that adaptive explanations are not sufficient for understanding spatial structure in this old-growth forest. If so, the role of Gotjawal terrain in terms of creating extremely diverse microhabitats and subsequently stochastic processes of survival and mortality of trees, both of which ultimately determine spatial patterns, needs to be further examined.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.616-619
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• 2007

Nowadays, urbanized area expands its boundary, and distribution of urbanized area is gradually transformed into more complicated pattern. In Korea, SMA(Seoul Metropolitan Area) has outstanding urbanized area since 1950s. But it is ambiguous whether urban distribution is clustered or dispersed. This study aims to show the way in which expansion of urbanized area impacts on spatial distribution pattern of urbanized area. We use quadrat analysis, nearest-neighbor analysis and fractal analysis to know distribution pattern of urbanized area in time-series urban growth. The quadrat analysis indicates that distribution pattern of urbanized area is clustered but the cohesion is gradually weakened. And the nearest-neighbor analysis shows that point patterns are changed that urbanized area distribution pattern is progressively changed from clustered pattern into dispersed pattern. The fractal dimension analysis shows that 1972's distribution dimension is 1.428 and 2000's dimension is 1.777. Therefore, as time goes by, the complexity of urbanized area is more increased through the years. As a result, we can show that the cohesion of the urbanized area is weakened and complicated.

• 한국염색가공학회지
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• 제26권4호
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• pp.339-346
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• 2014

To give a positive effect on dispersion behavior of high performance fibers $Vectran^{(R)}$ in water with reference to wet-laid nonwoven technology, 9 kinds of sulfonate type anionic surfactants were chosen to study. After dispersion experiment, the number and the area occupied by fibers in each sample were counted and figured to calculate the index of dispersion in conjunction with quadrat analysis. Similar tendency was observed in the results of two experiments. The sample without addition of any surfactant resulted in the most aggregated dispersion behavior. As the length of alkyl group attached to sulfonate increases, the sample shows more dispersed behavior. The sample with the surfactant having the aryl group and the longer alkyl group shows the most dispersed behavior and it can be seen with the naked eye as well.

• 한국경제지리학회지
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• 제10권3호
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• pp.319-331
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• 2007

도시화 지역은 지역발전과 더불어 공간적 범위가 확대되고 있다. 수도권 역시 예외는 아니어서 1960년대 이후 우리나라의 경제개발을 주도하며 도시화 지역의 공간적 범위가 확대일로에 있다. 그러나 도시화 지역의 공간적 분포를 평가함에 있어 그 분포 양상이 집적형태인지 임의적 형태인지 아니면 분산된 형태인지는 정확히 판단하기 어렵다. 즉, 시기가 지남에 따라 도시화 지역이 확대되기는 하지만 정량적으로 그 분포를 판단하기란 쉽지 않다. 본 연구는 GIS의 통계적 분석 기법을 이용하여 도시화 지역의 확대와 성장이 도시화 지역의 분포 패턴에 어떠한 영향을 주었는지를 살펴보고자 하는 것이다. 시계열적 도시성장 과정에서 수도권 내 도시화 지역의 분포패턴을 파악하고자 래스터 기반의 GIS 분석방법, 방격 분석(quadrat analysis), 그리고 최근린 분석(nearest neighbor analysis)을 사용하였다. 실험 결과 수도권의 도시화 지역의 집적정도는 1980년대 초반까지는 증가하다가 그 후로는 약화되는 것으로 분석되었다. 또한 1980년대 중반 이후 수도권 내에서는 외연적 성장이 약화되고 비지적 도시성장 또는 도로망과 연계한 소규모 개발이 증가함을 알 수 있었다.

• 농업과학연구
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• 제10권1호
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• pp.22-27
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• 1983

보문산의 관목시(灌木尸)을 대상(對象)으로 수종(樹種)의 종군(種群) 분류(分類)와 천이(遷移) 계열(系列)을 추정(推定)하기 위하여 $5{\times}5m$의 quadrat 22개소(個所) 선정(選定)하였다. 관목(灌木)의 분석(分析)에는 reciprocal averaging(RA) ordination 방법(方法)을 사용(使用)하였으며 다음과 같은 결과(結果)를 얻었다. 1. 보문산에 출현(出現)한 관목수종(灌木樹種)은 45종(種)이었으며 우세종(優勢種)은 Quercus aliena, Quercus serrata, Rhododendron mucronulatum 등(等)이다. 2. RA ordination으로 분석(分析)한 결과(結果) 보문산의 관목(灌木)은 Zanthoxylum schinifolium에서 Spiraea prunifolia for. simpliciflora-Rubus crataegifolius 를 거쳐 Quercus류(類)로 천이(遷移)되며, 또 하나는 Stephanandra incisa-Corylus heterophylla에서 Lespedeza maximowiczii를 거쳐 Quercus류(類)로 천이(遷移)된다.

• 한국수산과학회지
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• 제44권3호
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• pp.298-307
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• 2011

The species composition and distributions of subtidal marine algae on the east coast of Korea were studied. We examined all species found in permanent quadrats at three depths (3 m, 5 m and 10 m) at Sacheon between October 2008 and December 2009. Coverage and frequency data were collected monthly via underwater photography and analyzed using a modified photo quadrat method. Of the 82 species identified, 10 were chlorophytes, 21 were phaeophytes, 50 were rhodophytes, and one was a seagrass. The largest number of species (59) was found 10 m deep, while the fewest (39) species were present at 5 m. A total 17 species (two green, five brown, and 10 red algae) occurred at all three depths. The vertical distribution of the study site was characterized by the melobesioidean algae, Ulva pertusa, Sargassum confusum, Phyllospadix iwatensis, and Codium arabicum at 3 m deep, melobesioidean algae and U. pertusa at 5 m deep, and Corallina pilulifera, Prionitis cornea, Chondracanthus tenellus and melobesioidean algae at 10 m deep. Given that coralline algae such as melobesioidean algae and C. pilulifera play important roles in coastal ecosystems, thorough studies on the spatial and temporal variations of coralline algae and the dynamics of marine algal communities on the east coast of Korea are now required.

• 한국환경복원기술학회지
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• 제27권1호
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• pp.31-44
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• 2024

The coastal dune ecosystem is one of the ecosystems under the most development pressure in Korea. Therefore, it is necessary to study the ecological location and related ecological phenomena of coastal dune plants, but related studies are lacking. Through this study, we intend to conduct research on the structure and restoration of dune plants, focusing on the coastal dunes in Jeju Island, which are affected by artificial development pressure and the continuous increase in tourists among many coastal dunes in Korea. Ecosystems of coastal sand dunes for vegetation survey in Jeju Island are selected based on naturalness and preservation. In this study, 23 major coastal dunes on Jeju Island including Udo were selected. In the coastal dunes of Jeju Island, a whole species survey and quadrat survey were carried out. The vegetation survey at study sites were conducted on May to September 2022, when the vegetation is clearly visible. At the survey site, the dune area was identified at the beginning and the plant species were recorded until no more new species appeared. Vegetation survey in the field was performed by 103 quadrat establishments and was conducted using Braun-Blanquet method. A total of 277 species appeared, and the most common species were Vitex rotundifolia and Calystegia soldanella. The frequency of both Vitex rotundifolia and Calystegia soldanella was approximately over 90%. The proportion of woody and herbaceous in all emerging species was 7.2% and 92.8%, respectively. The total number of species found in the quadrat survey was 98. As a result of classifying plant communities based on species dominance in the quadrats, it was analyzed into 30 plant communities. The plant communities that appeared with a frequency of 2 or more on the main island of Jeju were Vitex rotundifolia, Imperata cylindrica var. koenigii, Ischaemum antephoroides, Wedelia prostrata, Elymus mollis, Calystegia soldanella, Artemisia scoparia, and Tetragonia tetragonoides. The DCCA(detrended canonical correspondence analysis) based on the vegetation and environment factor matrix showed that the height and covers of the dominant plant species explain significantly the variation and distribution of coastal sand dune species on Jeju island. Thus, we may propose a plan to restore the coastal dunes of Jeju island as helping colonization and establishment of mainly sand dune native perennials and trees, preserving native plant communities that are declining and preserving present tree strips of Pinus thunbergii, Litsea japonica, Pittosporum tobira and Vitex rotundifolia.

• Journal of Ecology and Environment
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• 제37권2호
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• pp.81-90
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• 2014

This study examined the main factors affecting the distribution of Phytolacca americana, an exotic plant species in Korea, in coastal sand dunes. The areas examined from June 2004 to February 2006 were in Sindusagu where was located on Sindu-ri, Wonbuk-myen, Taean-gun, Chungcheongnam-do. The vegetation, sediment properties, sizes and ages of Robinia pseudoacacia, P. americana and Pinus thnunbergii and spatial distribution of P. americana were assessed. Firstly, correlation coefficients (CC) between P. americana's root biomass and sediment properties were not significant. Secondly, of the four community types, P. americana was not in the mixed herbaceous community and its density was the highest in the P. thunbergii-R. pseudoacacia and R. pseudoacacia community The Poisson distribution analysis revealed the distribution of P. americana to be severely clumped. The root biomass of P. americana and the basal area of R. pseudoacacia were significantly correlated, but the CCs between P. thunbergii and other two species were not significant. The ages of P. americana and R. pseudoacacia in a quadrat were significantly correlated. Thirdly, P. americana's ages in a quadrat were mostly similar to each other. Therefore, the spatial distribution of P. americana was largely influenced by R. pseudoacacia but not by the sediment properties, and plants in a narrow area were concurrently germinated.

• Spatial Information Research
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• 제6권1호
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• pp.11-23
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• 1998

GIS 분야에서 지도 일반화는 공간자료의 상세도를 결정하여 효과적으로 자료를 가시화(Visualixation)하거나 자료의 해상력을 변화시켜 변환하는 기능을 수행한다. 최근까지 지도 일반화는 선사상 (Line Features)에 집중되었고, 수치지도를 구성하고 있는 정보량과 그 중요성에 비하여 점사상 (Point Features)에 대한 연구는 상대적으로 미미하였다. 이러한 맥락에서 본 연구는 점사상에 대한 구체적인 일반화 방안을 모색하는데 목적을 둔다. 특히 점사상의 일반화에서 원자료의 기하학적 특성을 파악하는데 가장 중요하게 고려한 요소로 점사상의 분포패턴을 선정하였다. 즉 'Grieg-Smith방법'을 활용한 방격분석 (Quadrat Analysis)과 최근린분석 (Nearest-Neighbour Analysis)를 통해 점사상이 갖고 있는 분포패턴의 특성을 찾아낸 다음, 이를 변형시키지 않도록 일반화의 기준거리(Threshold)를 설정하여 점사상을 제거하는 방법을 통해 점사상의 일반화를 시도하였다. 따라서 이 연구에서 제시한 점사상의 일반화 방안은 원래 점사상이 갖고 있는 기하학적 특성을 최대한 유지한다.