• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.132-141
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• 2006

Artificial structures have been designed as pilot structures to promote the creation and restoration of tidal flats. However, little information is available as to whether such artificial construction affects the macrobenthic community structure. We monitored the variation of the macrobenthic community structure and species composition near natural and artificial structures (seaweed and a timber fence) on the tidal flats near the Iwon Dike, Korea. In total, 137 macrobenthic species were recorded during this study, predominantly crustaceans (47%), polychaetes (18%), and molluscs (27%). Polychaetes comprised over 50% of the total density, followed by gastropods (38%) and crustaceans (11%). Macrobenthic species composition in the artificial and natural areas, was initially similar, but it differed after 7 months. The gastropod Umbonium thomasi, the most dominant species, was present at both sites in the first month after the start of the experiment, but disappeared at the artificial sites within 7 months, suggesting disturbance by the environmental factors. The number of species and diversity (H') varied significantly within sites at the beginning of the experiment, but no difference was observed after 7 months. Multivariate analysis (multidimensional scaling) revealed significant differences in community structure between the artificial and the natural areas from 7 months after the start of the experiment, except from 18 to 21 months. The community structures were mainly influenced by U. thomasi. Community structure at the artificial sites was affected by environmental variables, such as carbon, COD/IL sulfide, loss of ignition, kurtosis and silt, which changed over time. We observed no significant correlations between environmental variables and the dominant species, except in the case of Spio sp. and Macrophthalmus dilatatus, suggesting that the biological interactions and temporary disturbances such as typhoon, as well as the effects of artificial structures may also be important regulating factors in this system.

• The Korean Journal of Applied Statistics
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• v.34 no.6
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• pp.945-956
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• 2021

In this study, we considered the algorithm of Legendre and Legendre (2012), which derives canonical correspondence analysis from weighted principal component analysis. And, it was proved that the canonical correspondence analysis based on the weighted principal component analysis is exactly the same as Ter Braak's (1986) canonical correspondence analysis based on the Gaussian response model. Ter Braak (1986)'s canonical correspondence analysis derived from a Gaussian response curve that can explain the abundance of species in ecology well uses the basic assumption of the species packing model and then conducts generalized linear model and canonical correlation analysis. It is derived by way of binding. However, the algorithm of Legendre and Legendre (2012) is calculated in a method quite similar to Benzecri's correspondence analysis without such assumptions. Therefore, if canonical correspondence analysis based on weighted principal component analysis is used, it is possible to have some flexibility in using the results. In conclusion, this study shows that the two methods starting from different models have the same site scores, species scores, and species-environment correlations.

• Journal of Ecology and Environment
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• v.47 no.3
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• pp.134-145
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• 2023

Background: The flowering and fruiting periods play an important role in biological processes. The deciduous dipterocarp forest is an important forest type in Thailand, however the phenological studies are still limited, particularly in different plant life forms. Thus, the present study focused on the flowering and fruiting phenology of herbs, climbers, shrubs, and trees in the deciduous dipterocarp forest at Lampang province of Northern Thailand. Field visits were made to record plant life forms and observe reproductive phenological events at monthly intervals from November 2018 to October 2019 and September to December 2020. Results: The phenological observations were based on 126 species of 45 families and 102 genera. Flowering and fruiting periods showed similar patterns in herbaceous plants, climbers, and shrubs. Most of these species produced flowers and fruits from the end of the rainy season (October) to the winter season (November-January). Whereas most of flowering and fruiting trees were found from the summer season (March-April) to the beginning of the rainy season (May-June). Most of the dry-fruited species occurred during the dry period (winter and summer seasons), while the majority of fleshy-fruited species dominated in the wet period (rainy season). The statistical analysis supported the phenological patterns of flowering and fruiting in the present study. There were significant negative correlations between the number of flowering and fruiting species and temperature. The number of flowering and fruiting species is significantly impacted by the interaction between seasons and plant life forms. Conclusions: Plant life form seems to be the important factor that affects the different phenological patterns in the studied plants. The abiotic and biotic factors play major roles in reproductive phenology. However, long-term study and in-depth phenological observations are necessary for better understanding.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.19-19
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• 2014

This study included the analysis of mushroom data collected from Mt. Chiak in Gangwon-do using various methods. Former studies of Korean mushrooms are limited by regional characters and there is less species diversity among the regions. This study tried to find a way for the forecast of mushroom distribution and appearance by indexes of species diversity. The indexes used in this study include the number of fungi (N), the number of species (S), similarity index (C), richness index (R1, R2), variety index (V1, V2), evenness index (E1, E2, E3, E4, E5), and dominance index (D1) to analyze variety of species diversity. Analyses of data of fungi using a multistage cluster sampling indicate that the average value of C for years was higher than the average value of C for areas. The mushrooms consisted of 208 species in 686 individuals in limited fungal collection from 2002 to 2003. One hundred thirty nine species in 393 individuals were collected in 2002, and 122 species 293 individuals were collected in 2003. The individuals collected in 2003 were smaller than 2002's individuals. Similarity, richness, and variety indexes' values of 2003 were reduced than 2002's values but dominance index of 2003 was increased than 2002's value. Generally the species diversity of the environment to evaluate the index of similarity, richness, and variety was a higher index; dominance index was lower than that of the surrounding environment, suggesting a good diversity. As a result, the occurrence of mushrooms in the surrounding environment and the various factors seem fell in 2002 compared to 2003. The majority genus of the limited fungal collection was Mycena genus in 63 individuals; the majority species was Laccaria laccata in 34 individuals. Ninety three species in 106 individuals were collected by the extended collection and the majority genus of the extended collection was Amanita genus in 17 individuals; the majority species was Amanita citrina (Schaeff.) Pers. which was found in 5 individuals. This demonstrates that periodical similarity's value was 0.159 is higher than special similarity's 0.119. This indicates that the probability of the appearance of same mushrooms in the same area in following year is higher than the probability of the appearance of same mushrooms in the surrounding area in same year. The value of coefficient of variation (CV), in which the amount of change is much or less by N is higher than the CV value by S. CV value of dominance index(D) was the highest r point among other indexes, and evenness index (E) was the lowest point among other indexes. The correlation matrix with 66 combinations between the indexes, the combinations with correlations was 46 combinations. These results revealed that indexes of R1, V2, and E1 were proper to represent species diversity of fungi based on the correlation matrix and the theory of statistical independence which means there is no or less mutual association. This research would contribute to the study about variable living creature by measuring method and in the future this would be used to figure out regulation about fungi with their correlation, values in ecosystem, develop improving new models about agricultural fungi species and numbers by investigating agricultural variable species.

• Journal of Ecology and Environment
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• v.31 no.4
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• pp.327-331
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• 2008

Serpentine soils are distributed in a small area in Korea, and generally exhibit high contents of Ni, Cr, Fe, Mn, Co and Mg. We investigated the growth of woody plants and herbs in the Andong serpentine area, Korea. Pinus densiflora and P. rigida growing on serpentine soils have high contents of Fe, Mg, Ni and Co, with contents approximately twice as high as those of non-serpentine plants. Tree species on serpentine soil also had lower ratios of tree height/DBH than trees in a control area. In greenhouse culture experiments on two bodenvag herb species, Setaria viridis and Cymbopogon tortilis, the biomass of the plants was significantly affected by soil type but not by seed origins. After 66 days, the growth of S. viridis and C. tortilis seedlings was significantly inhibited in serpentine soil, and the dry weight of each species showed significant negative correlations with soil heavy metal contents (Ni, Co and Cr). These results suggest that the growth of plants was inhibited by properties of the serpentine soil, and in particular, their high heavy metal concentration, which induced dwarfing in woody plants and reduction of total plant biomass in herbs.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.154-161
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• 1993

To investigate the structure and the conservation strategy of Taxus cuspidata forest and at Birobong area in Sobeaksan. 24 plots(400$m^2$) set up with random sampling method. Four groups were classified by cluster analysis. High positive correlations was proved between Quercus mongolica and Symplocos chinensis, Rhododendron schlippenbachii and Pinus densiflora, Taxus cuspidata and Acer pseudo-sieboldianum, Prunus padus and Eunonymus macroptera, Acer mono and Styrax obassia, and high negative correlations was proved between Quercus mongolica and Taxus cuspidata, Prunus padus and Eunonymus macroptera, Rhododendron schlippenbachii and Taxus cuspidata, Acer pseudo-sieboldianum, Prunus padus and Eunonymus macroptera. Species diversity(H') of investigated area was calculated 1.3702-2.9119. To conserve Taxus cuspidata forest at Birobong area in Sobeaksan, research and rescription on the declining of Taxus cuspidata. forest was needed and Quercus mongolica, Styrax obassia, Tripterygium regelii and Weigela subsessilis in the Taxus cuspidata forest should be cleared out.

• Korean Journal of Environment and Ecology
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• v.5 no.1
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• pp.25-31
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• 1991

To investigate the structure and the conservation of Abies koreana forest at Banyabong area in Chirisan, 38 plots(100$m^2$) set up with random sampling method. Dead individuals of Abies koreana were 12.81%. were observed mainly upper-layer trees. A few seedlings of Abies koreana were observed. Three groups were classified by cluster analysis. High positive correlations was proved between Abies koreana and Rhododendron mucrolunulatum var. ciliatum, and High negative correlations was proved between Abies koreana and Fraxinus sieboliana, Carpinus cordata, Sasa purpurascens and Cornus controversa. Species diversity(H') of investigated area was calculated 1.9796-2.7509. To conserve Abies koreana forest at Banyabong area in Chirisan. Research and prescription on the declining of Abies koreana was needed and Quercus mongolica, Acer pseudo-sieboldianum, Fraxinus sieboliana, Carpinus cordata, Sasa purpurascens and Cornus controversa in the Abies koreana forest should be cleared out.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.145-151
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• 2006

The purpose of this study was to analyze the relationship between the annual variation in diameter growth of Quercus spp. and climatic factors such as monthly temperature, precipitation and solar radiation in central and northern Korea. Annual diameter growth was measured by using stem cores of 262 Quercus trees, and the correlation between the diameter growth and the climatic factors was analyzed. Mean diameter growth of Quercus spp. in Jungwangsan was larger than that in Woraksan, and mean diameter growth by the species was large in order of Q. serrata>Q. variablis>Q. mongolica>Q. dentata. The diameter growth pattern of Quercus spp. in Woraksan was different from that in Jungwangsan. Positive correlations between diameter growth of Quercus trees and temperature or the solar radiation during July were found in Jungwangsan. Significant correlations between diameter growth and solar radiation during March and precipitation during June were found in Woraksan. It is suggested that climatic factors similarly affect the diameter growth of Quercus spp. in a mountainous terrain, but influences of the climatic factors depend on other environmental conditions such as altitude, topography and soil depth.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2005.04a
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• pp.21-32
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• 2005

To investigate the vegetation structure of mountain ridge from Bubong to Poamsan, 16 plots$(400m^2)$ set up with random sampling method were surveyed. Three groups Quercus mongolica-Pinus densiflora community, Quercus variabilis-Pinus densiflora-Quercus mongolica community were classified by cluster analysis. Quercus mongolica was found as a major woody plant species in the ridge area from Bubong to Poamsan, and partly in lower elevation was occupied by Quercus variabilis and Pinus densiflora. High positive correlations was proved between Lespedeza maximowixcii and Pinus koraiensis, Fruxinus sieboidiana and Rhododendron mucronulatum, Acer mono and Weigela subsessilis, and relatively high negative correlations was proved between Symplocos chinensis for. pilosa and Fraxinus sieboldiana, Rhododendron mucronulatum Species diversity(H') of investigated groups were ranged $0.9066\~1.0821$, and it was relatively low compared to those of mountain ridge area of other national parks.

• The Korean Journal of Ecology
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• v.3 no.1_2
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• pp.1-10
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• 1980

This study was carried out to find out the correlation between plant groups and environomental gradient in the native grassfild near Kang Nam Express Terminal from August 26 to september 15, 1977. The correlations among plant species were calculated by using the method of x2 and the various relationships among soil environmental gradients were grouped by means of correlation coefficient. As a result, both the species and the soil environmental factors could be subdivided into four groups, and the four groups of the native grassfield were turned out to be correlated with the four groups of soil environmental factors. The first plant group (Panicum dichotomiflorum, Chenopodium album, Bidens forndosa, Humulus japonicus, Alopeculus amurensis, Potentilla fragarioides, Centipeda minima, Beckmannia erucaeformis) was formed in the releve 1∼10 reagions, organic matter by Turins's method, Total N, Exchange Ca and total of Exchange K, Na, Kg, Ca were abundent. The second plant group (Digitaria sanguinalis, Paltulaca oleracea, Echinochlea macrocrovi, Cyperus amuricus) was formed in the relve 11∼18 reagions, where Exchange Ca and total of Exchange K, Ng, Mg, Ca were little but Exchange A1 and sand were aburdent. In relve 19∼20 reagions, with much of Exchange Ca, total of Exchange K, Na, Mg, Ca, pH and a little Exchange Al, was found the third plant group (Pycreus sanguinoloentus, Cyperus amuricus, Ludwigia prostrata, Echinochloa echinata, Polygonum thunbergii, Salix glandulosa seedling) The fourth plant group (Cassia nomame, Polygnoum perfoliatum, Setaria viridis, Glocien ussuriensis, Lactuca indica, setaria glauca, Artemisia capill aris, Artmisia asiatica, Calamagrostis arundinacea, Kummerowia striata, Denothera odorata, Artemisia japonica, Carey laceolata) was formed in relve 21∼25 reagions, where organic matter by loss on ignition, Exchange Mg and Maximum water holding capacity were abundent but sand was a little. Thus it can be concluded that there is a close relationship between the vegetation group clasified by meaus of x2 and the environtal factors of soil devided by means of correlations coefficient.