• Journal of Plant Biology
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• v.15 no.1
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• pp.33-41
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• 1972

Nine shrub layer communities under two relatively well conserved natural summer green forests in the central region of Korean Peninsula were studied for the pattern of stem distribution in terms of Greig-Smith's multiple split-plot experiment and for the association between the population of the two main species in terms of Kershaw's covariance analysis respectively. Four contiguous belt transects, $4{\times}64m size with 1{\times}1m$ basic unit, were set in each shrub layer communities. Significant primary clumps with $1{\times}1m or 1{\times}2m$ dimension wer observed consistently throughout the nine study sites. The primary clumps themselves were significantly distributed either regularly or at random. The association between the two principal species of each shrub layer is highly significantly either positive or negative in $1{\times}1m or 1{\times}2m$ dimension. As the plot size increases from $1{\times}1m to 8{\times}8m$ the associational trends were changed from negative to positive direction in one forests. But the change from positive to negative direction and the consistent negative association were also observed from the other forest. All of the association trends were observed only from $1{\times}1m to 4{\times}4m$ dimension. These results are suggestive that the distributional pattern of the shrub layer species under the summer green forest is simple mosaic fashioned with $1{\times}1m or 1{\times}2m$ dimension. The rest of the principal species are located in that matrix. The simple mosaic pattern of two principal species are located in that matrix. The simple mosaic pattern of two principal species seems to be controlled by change in micro-environmental pattern. Differences between the primary random group and clumped group among sites also suggest that competition exists for light or/and soil between primary clumped groups.

• Journal of Ecology and Environment
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• v.37 no.2
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• pp.105-111
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• 2014

To elucidate whether small diameter at breast height correlates with tree death in an overcrowded tree population, we analyzed self-thinning occurring over the course of 37 years in naturally established Pinus densiflora populations in Sugadaira, central Japan. As trees grew, their diameters at breast height increased and the number of trees consequently decreased. Spatial distribution, which was initially clumped, changed accordingly, first becoming random and finally uniform. We calculated the "available area" of individual trees to elucidate the contribution of this parameter to tree mortality. Small diameter at breast height was strongly correlated with tree death, with a slight correlation observed between tree death and small available area of individual trees.

• Journal of Ecology and Environment
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• v.41 no.8
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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.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.184-190
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• 2004

The influences of impeller types on morphology and protein expression were investigated in a submerged culture of Aspergillus oryzae. The impeller types strongly affected mycelial morphology and protein production in batch and fed-batch fermentations. Cells that were cultured by propeller agitation grew in the form of a pellet, whereas cells that were cultured by turbine agitation grew in a freely dispersed-hyphal manner and in a clumped form. Pellet-grown cells showed high levels of protein production for both the intracellularly heterologous protein (${\beta}$-glucuronidase) and the extracellularly homologous protein (${\alpha}$-amylase). The feeding mode of the carbon source also influenced the morphological distribution and protein expression in fed-batch fermentation of A. oryzae. Pulsed-feeding mainly showed high protein expression and homogeneous distribution of pellet whereas continuous feeding resulted in less protein expression and heterogeneous distribution with pellet and dispersed-hyphae. The pellet growth with propeller agitation paralleling with the pulsed-feeding of carbon source showed a high level of protein production in the submerged fed-batch fermentation of recombinant A. oryzae.

• Journal of Life Science
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• v.20 no.9
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• pp.1287-1293
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• 2010

The spatial distribution of alleles and geographical distances of a Carex humilis population on Mt. Giri in Korea were studied. A total of 102 DNA fragments (bands) were found among 107 plants. Among these 102 bands, 48 (47.1%) bands were polymorphic. In a simple variability of subpopulations by the percentage of polymorphic bands, distances I and V exhibited the lowest variation (16.7%). Distance VIII showed the highest variation (22.6%). The total genetic diversity (H) was 0.076 across species. Class VIII had the highest H (0.093), while class I had the lowest (0.063). Genetic similarity of individuals was found among subpopulations at up to a scale of 60 m distance, and this was partly due to a combination of alleles. Within the Mt. Giri population, a strong spatial structure was observed for RAPD markers, indicating a very low amount of migration among subpopulations and that the distribution of individual genotypes of a given population was clumped. The present study demonstrated that analysis of RAPD markers could be successfully used to study the spatial and genetic structures of C. humilis.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.402-406
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• 2015

This study aims at favorable environmental conditions by river otter residing in Hongcheon river ecosystems using spraints along the river. Otter spraints were indicative of habitat use pattern and marking a territory in the areas. Nae-chon and Kuneob-chon river otter spraints were collected totaling 478 with 8 times during 2009-2011, and based on the number river use patterns were analyzed with the technique of index of dispersion. Results with larger than one indicated that river otter habitat use pattern were not random; instead they used preferred areas for habitat use. 'I' values greater than one indicate a clumped distribution and lower than one indicate random distribution. This study also demonstrated that we need a sophiscated linear model that should be developed to identify key habitat elements in river ecosystems.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.327-333
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• 2005

For the first time in Korea, plant size, distribution pattern and root growth form of Tamarix chinensis were surveyed at natural stand in Shiwha Lake, from June to July in 2005. T, chinensis grew in the range of 350 m towards north-south and 270 m in east-west direction. The mean number of stems germinated from same root system was 1.9. On the stem base, the numbers of living and dead plants were 1,398 and 114, respectively. Mean perimeter and height of 1,398 plants were $5.9{\pm}3.2$ cm and $159{\pm}51$ cm, respectively. By dividing into 10 classes based on the perimeter size, the largest number of plants were included in the second smallest class category. However, by dividing into 10 classes on the bases of plant height, variation in the number of plants along the height showed normal distribution curve. The heights of dead plants were small in perimeter but diverse in height. On the root base, the number of plants was the greatest in the smallest size class, and conspicuously decreased with size increment. Distribution of T. chinensis was clumped pattern. Age of the largest plant was 8-year. T. chinensis had two types of root growth. One was horizontal growth in the periphery of soil surface, and the other vertical growth.

• Journal of Plant Biology
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• v.13 no.1
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• pp.33-46
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• 1970

Pinus densiflora stands are common secondary forest communities on infertile soils in Korea. The stands are results of long severe past biotic pressure such as cutting, burning and grazing. These could be regarded as biotic climax in Korea. Because of their prevalent occurrence, relatively simple species and age composition, and their domestic economic importance, study of their distributional patterns may give some basic knowledge for better utilization of land resources in Korea. To detect distributional patterns and interspecific associations ten pine stands, each of which was homogenious with respect to topography and physiognomy, were subjectively selected from pine stands in Kyunggi Province near Seoul in 1969 and were made object of this study. Four contiguous systematic samples of count for trees, shrubs and seedlings from belt transects were collected from homogeneous areas within ten natural pine stands. The belt transect was 64m or 128m in length, and 1m, 2m or 4m in width. Basic units within the transect ranged from 64 to 256. The data from the contiguous transects were analysed in terms of multiple split-plot experiment. Departure from randomness of stem distribution, i.e., pattern, was tested in terms of variance mean ratio. For the detection of association between species, correlation coefficient was calculated for different block sizes. The values of ${\gamma}$ were tested by the usual t-test. Fine trees within one of the stands showed significant regular distribution through out the blocks. Within other eight stands pines were randomly distributed at basic unit with 4$\times$4m, 2$\times$2m, 2$\times$1m and 1$\times$1m. One significantly clumped distribution at basic unit 2$\times$2m, however, was observed from one of the pine stands. These randomly distributed groups were themselves significantly regularly distributed throughout the blocks for four pine stands. For the other four pine stands, in addition to the random distribution at the basie unit(the primary random group), randomly distributed groups with 32m dimension(the secondary random groups) were also observed. Both the primary and the secondary random groups were significantly regularly distributed at the rest of blocks. Pine seedlings were not distributed randomly thoughout the blocks. Within three of the ten stands they were contagiously distributed. Important shrub species underneath pines such as Querus serrata, Q. acutissima, Leapedeza intermedia, Rhododendron Yedoense var. poukhanenae, Juniperus utilis, Rhododendron mucronulatum var. ciliatum shnwed consistently similar distributional pattern with the pine at each stand. The shrub species pairs; Rhododendron Yedoense var. poukhanenae/Quercus serrata, Rhododendron mucronulatum var. ciliatum/Lespedeza intermedia were significantly negatively associated from 1m to 4m dimensional block sizes but became significantly positively associated from 8m sized blocks on. On the other hand the shrub species pairs; Lespedeza intermedia/Robinia Pseudoacacia, and Lespedeza bicolor var, japonica/Lespedeza intermedia were also significnalty negatively associated from 1m to 8m sized blocks but became significantly positively associated from 16m sized blocks on. The associational pattern between Rhododendron mucronul tun var. poukhanenae and Lespedeza intermedia was not consistent throughout the stands. In some stands negative associations were observed throughout the blocks except NS 32. From these observatons micro-edaphic variation within the pine stands seems not to be great enough to cause distributinal difference of pine trees within the ten pine stands. Among each species and pine seedings, however, the edaphic variation within the pine stands may be great enought to cause distributional variation.

• Journal of the Korean Institute of Landscape Architecture
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• v.14 no.3
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• pp.33-45
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• 1987

The Seonjeong royal tomb is one of many historic sites in and around Seoul city and its natural environment and landscape have born damaged seriously by heavy use. So conservation planning with an estimation of reasonable carrying capacity shall be required In aspect of not only historic site conservation, but also urban forest and nature park management. Eight sites were sampled with clumped sampling method during July of 1986 and five quadrats were examined in each site. Environmental factors, actual vegetation, and environmental impact grade were investigated in field and vegetational structure was analyzed by estimation of importance value, species diversity, similarity index, DBH class distribution, etc. The result of this study can be summarized as follows. 1. Damage on soil and vegetation of middle and lower layer increased according to amount of users'impact. 2. Semi - natural vegetation covered 63% of the total area(22.2 ha) and its major species were Pinus densiflora, Quercus aliena, Q mongolica, Sorbus alnifolia, etc. Pinus densiflora was a dominant species in heavy impact area. 3. Environmental impact grade 3, 4 and 5 area covered 51% of the seminatural vegetation, Especially, the area of impact grade 4 and 5 should be restored because self-refair seemed to be impossible. 4. The semi-natural vegetation was classified with four plant communities; two P.densiflora comm., Q. mongolica-P. densiflora comm. and Q. aliena comm. One of the P. densifolra comm. was destroyed seriously with no younger trees in middle and lower layer by overuse impact and would be bareland soon. But Q. aliena comm.in light impact area showed just completion of plant succession from P. densiflora comm.

• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.131-137
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• 2002

This study was conducted to clarify the characteristics of bird community and habitat types in Mangyeong River area from Aug. 1999 to Jun. 2000. Paddy field was the most dominant land use type. Water area, mudflat, shrub field, urban area and green house were also dominant land use types in study area. Eighty-eight bird species were recorded during study period. Maximum number of species and individuals were shown as 58 species and 7,084 individuals in Oct. and Jan., respectively. There were low number of diving ducks and clumped pattern of waterfowl distribution of bird community in Mangyeong River area. Dabbling ducks distributed at upper reaches near Samrye Bridge, and plovers and sandpipers at lower reaches near estuary. Those results suggest that creation of pools over one meter water-depth and restoration of paddy field into riparian zone with diverse shrubs are required to increase the bird diversity in the Mangyeong rived.