• 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.

• 한국작물학회지
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• 제28권3호
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• pp.319-322
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• 1983

벼 이앙후에 발생되는 잡초를 조사하여 벼와의 경쟁적 영향을 해석함에 있어 가장 적은 노력으로 전체잡초발생상태를 대표할 수 있는 최소표본크기(minium quadrat size)와 최소표본회수(minimun quadrat number)를 초종일표본변적(species-area) 및 초종일표본회수(species-quadart number) 관계식에 의해 조사하였다. 1. 초종일표본면적, 또는 초종일표본회수 관계식에서 다같이 표본면적, 또는 표본회수가 증가하게 됨에 따라 얻어지는 초종증가는 처음에는 급속도로 증가하고, 서서히 증가속도가 완만해지며, 어느 한계점을 지나면 더 이상의 초종증가는 없이 평형상태를 유지하는 특징적인 곡선을 보였다. 2. 표본추출면적, 또는 표본 추출회수를 10% 증가시킴에 따라 얻어지는 초종 증가율이 10%되는 관계를 고려한 최소표본추출 회수는 3회였다.

• 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.

• 아시안잔디학회지
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• 제9권2호
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• pp.131-136
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• 1995

The herb, shrub, understory and canopy strata, which arbitrarily delineated by size classes, were sampled separately. The former one were sampled by the pin-point quadrat method. And remaining three by size quadrats, diversity (H= =$\Sigma$ Pi log Pi) of of each stratum was estimated for each set of census data. Species diversity within a stratum was independent of sample plot size above a minimum cumulative area. Diversity based on plotless and plot samples could he determined by the same equation, and by pooling the data needed to estimate diversity of each stratum.

• 한국환경복원기술학회지
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• 제13권1호
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• pp.47-56
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• 2010

The main objectives of this comparative study were 1) to quantify the potential contribution of wood chips to revegetation on the cut slope in a constructed area, 2) to compare the floristic similarity of species composition whether existing of wood chips in the soil media or not. Wood chips were combined with soil media in the ratio of 30%. The thin layer (1 cm, 3 cm) soil media revegetation methods and the thick layer (10 cm) soil media revegetation method were constructed on the cut slopes by machineries respectively. Also, comparative experiments the existence of wood chips in the soil media were conducted to evaluate the effects of wood chips on revegetation works. The total size of quadrat was $300m^2$ ($100m^2{\times}3$). The results of monitoring for 3 years on cut slopes were as follows: 1) All the quadrat existed in the proper range for vegetation. 2) Species richness of quadrat including wood chips was 10% more than those of commercial soil medias. 3) The coverage rates of quadrat including wood chips were similar or superior to those of conventional methods. It can be concluded that the use of wood chips would be effective to promote establishment of diverse landscape and vegetation. However, it behooves to continue monitoring on succession of vegetation for ecological restoration. Finally, adequate wood chips deposit and gathering methods should be studied properly.

• 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.

• 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.

• 한국응용곤충학회지
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• 제49권4호
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• pp.313-324
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• 2010

논의 생물다양성에 관한 관심이 증가하면서 논 먹이망의 중요한 부분을 차지하고 있는 수서성 대형무척추동물을 정량적으로 평가하기 위한 효율적인 방법이 요구된다. 이를 위해, 강원도 춘천시와 충청남도 홍성군에 위치한 논에서 채집망과 방형구, 피이프형 채집기(core)로 얻어진 자료를 비교하여 적절한 채집기를 알아보았다. 채집망은 틀이 사각형이고, 바닥이 평평하기 때문에, 채집망의 조사 면적은 토양을 훑은 길이와 망의 넓이를 곱하여 측정되었다. 모든 채집물은 두 벼줄 사이에서 채집되었다. 대형무척추동물은 춘천과 홍성에서 24, 28분류군이 채집되었다. 춘천에서 분류군수는 세 가지 채집기에서 유사했지만(17-18분류군), 추정밀도는 그렇지 않았다(채집망, $1317/m^2$; 방형구, $1368/m^2$ core, $1810/m^2$). 홍성에서는 채집망에서 분류군 수가 가장 컸었지만(채집망 25분류군; 방형구, 21분류군 core, 16분류군), 추정밀도는 core에서 가장 높았다(채집망, $1586/m^2$; 방형구; $2595/m^2$; core $3704/m^2$). 각 채집기의 효율은 분류군에 따라 달랐는데, 채집망에는 주로 수서곤충류가 많았던 것에 비해 방형구에는 빈모류나 깔따구과 등 토양 속에 서식하는 종류에 대한 효율이 높았다. 논에 서식하는 수서곤충에 대한 정량자료와 희귀분류군에 대한 정성자료를 통시에 얻고자 하는 경우에는 채집망을 이용하여 논 가장자리와 논 내부에서 각 6회 정량채집하고, 논둑 근처와 논 가운데에서 정성채집을 수행되는 것이 시간 및 노동력 측면에서 가장 경제적 이라고 생각된다.

• Journal of Plant Biology
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• 제23권2호
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• pp.61-67
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• 1980

As a part of the environmental base line survey of the Onsan Industrial Base, Korea, marine algal communities were investigated using the quadrat method in Onsan-myon on the east coast of Korea from March to December of 1978. It was learned that the representative dominat species along the coast in the Onsan area throughout the year are Ulva pertusa, Pachymeniopsis elliptica, and Sargassum thunbergii. Both the number of algal species occurring in the quadrat (50$\times$50cm) and the total coverage were higher in March and September than in June and December. A total of 94 species (1 blue-green, 16 green, 25 brown, and 52 red algae) of marine algae was identified in this study.

• Journal of Plant Biology
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• 제23권1호
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• pp.3-10
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• 1980

Effects of thermal effluents on the marine algal communities were investigated with the quadrat method during June, 1977-December, 1978, at the intertidal zone of Kori Nuclear Power Plant, Southeast Coast of Korea. As a result, both the number of algal species occurred in quadrat (50$\times$50cm) and the total coverage were observed to be decreased in June, 1978, at three sites near the discharge point compared with those of previous year but being recovered afterwards. The representative dominant species at the coast of Kori Nuclear Power Plant were, on the whole, Corallina pilulifera, Pachymeniopsis elliptica, and Chondrus ocellatus. Among the species, the coverage of Corallina pilulifera appeared to be rather increased, while the vegetation of Chondria crassicaulis was found to be decreased particularly in 1978. Total 102 species (3 blue-green, 16 green, 30 brown, and 53 red algae) of marine algae were identified in this study. Among them 71 species were common to 133 species reported by previous investigators during 1969-1970.