• Title/Summary/Keyword: spatial distributional pattern

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Distribution Pattern and Feeding Preference of Asterias amurensis (Echinodermata: Asteriidae) in Tongyeong, Korea (통영해역에 서식하는 아므르불가사리의 분포 특성과 서식처에 따른 먹이 선호도 비교)

  • PARK Sang-Gyu;PARK Heung-Sik;YUN Sung Gyu;YI Soon Kil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.6
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    • pp.469-477
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    • 2004
  • This study examined distributional patterns of Asterias amurensis in Tongyeong, the central South Sea of Korea. The density of the sea star was estimated at 10 chosen sites in the inner and the outer parts of the Tongyeong coast from December 2000. The mean density of the species in this area was $2.4ind./m^{2}$. The seasonal surveys conducted at 3 arbitrary chosen sites (i.e., sea cage, reef and soft sediment) also showed that the abundance of the species at the sea cage site $(density:\;3.6\;ind./m^{2};\;biomass:\;250.7\;gwwt/m^{2})$ was significantly higher than at the reef site $(density:\;1.7\;ind./m^{2};\;biomass:\;63.5\;gwwt/m^{2})$ and the soft sediment site $(density:\;0.4\;ind./m^{2};\;biomass:\;18.9\;gwwt/m^{2})$. Densities were higher at sea cages areas than at reefs and soft bottom sites. At sea cage site, A. amurensis population exhibited a strong aggregated distributional pattern. In contrast, at reef and soft bottom sites, A. amurensis population showed a random distributional pattern. The spatial difference in prey species and its abundance was the primary factor determining the spatial heterogeneity of the sea star in its behavior characteristics. Experiments on the feeding preference indicated that A. amurensis had a strong selectivity on its prey, but this selectivity varied between populations living in different sites. In particular, A. amurensis populations at the reef site showed a strong selectivity on various sessile and mobile animals living in reef areas, suggesting that these animal groups may play a role as "windows for the survival of A. amurensis". These results suggest that the distribution of A. amurensis in Tongyeong is closely associated with abundance of prey species and the bottom composition.

Spatial Pattern of Larix gmelini in a Spruce-fir Valley Forest of Xiaoxing'an Mountains, China

  • Jin, Guangze;Liu, Liang;Liu, Zhili;Kim, Ji-Hong
    • Journal of Korean Society of Forest Science
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    • v.99 no.5
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    • pp.720-725
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    • 2010
  • On the basis of vegetation data in the 9.12 ha (380 m ${\times}$ 240 m) permanent sample plot of the spruce-fir valley forest in Liangshui National Reserve of Xiaoxing'an Mountains, the study was conducted to evaluate spatial distribution pattern and spatial association by using point pattern analysis for living and dead trees of Larix gmelini by DBH size class. The number of L. gmelini were counted as 59 living stems/ha (6.42 $m^2$/ha of basal area) and 34 dead stems/ha (2.86 $m^2$/ha of basal area). The distributional curve of diameter class exhibited bimodal shape. The analysis of spatial distribution patterns of all living larch stems noted the clumped distribution on the whole. The size of larch aggregates of dead stems was decreased as diameter class was increased. The distribution of dead stems became gradually randomized with decreased clumped size as the scale increased. Living stems and dead stems of the larch had positive spatial association at most of scales, illustrating that the occurrence of mortality of the larch tree was closely related to the distribution pattern of living larch trees.

Spring Dominant Copepods and Their Distribution Pattern in the Yellow Sea

  • Kang, Jung-Hoon;Kim, Woong-Seo
    • Ocean Science Journal
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    • v.43 no.2
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    • pp.67-79
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    • 2008
  • We investigated the relationship between mesoscale spatial distribution of environmental parameters (temperature, salinity, and sigma-t), chlorophyll-a concentration and mesozooplankton in the Yellow Sea during May 1996, 1997, and 1998, with special reference to Yellow Sea Bottom Cold Water (YSBCW). Adult calanoid copepods, Calanus sinicus, Paracalanus parvus s.l., Acartia omorii, and Centropages abdominalis were isolated by BVSTEP analysis based on the consistent explainable percentage (-32.3%) of the total mesozooplankton distributional pattern. The copepods, which accounted for 60 to 87% of the total abundances, occupied 73-78% of the copepod community. The YSBCW consistently remained in the northern part of the study area and influenced the spatial distribution of the calanoid copepods during the study periods. Abundances of C. sinicus and P. parvus s.l., which were high outside the YSBCW, were positively correlated with the whole water average temperature (p<0.01). In contrast, the abundances of C. abdominalis and A. omorii, which were relatively high in the YSBCW, were associated with the integrated chl-a concentration based on factor analysis. These results indicate that the YSBCW influenced the mesoscale spatial heterogeneity of average temperature and integrated chl-a concentration through the water column. This consequently affected the spatial distribution pattern of the dominant copepods in association with their respective preferences for environmental and biological parameters in the Yellow Sea during spring.

Cause-specific Spatial Point Pattern Analysis of Forest Fire in Korea (우리나라 산불 발생의 원인별 공간적 특성 분석)

  • Kwak, Han-Bin;Lee, Woo-Kyun;Lee, Si-Young;Won, Myung-Soo;Koo, Kyo-Sang;Lee, Byung-Doo;Lee, Myung-Bo
    • Journal of Korean Society of Forest Science
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    • v.99 no.3
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    • pp.259-266
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    • 2010
  • Forest fire occurrence in Korea is highly related to human activities and its spatial distribution shows a strong spatial dependency with cluster pattern. In this study, we analyzed spatial distribution pattern of forest fire with point pattern analysis considering spatial dependency. Distributional pattern was derived from Ripley's K-function according to causes and distances. Spatially clustered intensity was found out using Kernel intensity estimation. As a result, forest fires in Korea show clustered pattern, although the degrees of clustering for each cause are different. Furthermore, spatial clustering pattern can be classified into two groups in terms of degrees of clustering and distance. The first group shows the national-wide cluster pattern related to the human activity near forests, such as human-induced accidental fire in mountain and field incineration. Another group shows localized cluster pattern which is clustered within a short distance. It is associated with the smoker fire, arson, accidental by children. The range of localized clustering was 30 km. Beyond of this range, the patterns of forest fire became random distribution gradually. Kernel intensity analysis showed that the latter group, which have localized cluster pattern, was occurred in near Seoul with high densed population.

The Summer Spatial Distributional Pattern of Macrobenthic Fauna in Gwangyaug Bay, Southern Coast of Korea (광양만에 서식하는 대형저서동물의 하계 공간분포양상)

  • 최진우;유옥환;이우진
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.1
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    • pp.14-28
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    • 2003
  • The macrobenthic faunal community of Gwangyang Bay comprised 154 species and showed the overall mean density of 1,286 individuals/$m^2$. Polychaetes were the most important component of the macrofaunal community in species richness, abundance and biomass. The dominant species in abundance were poly-chaetes like Tharyx sp.(44.8%), Lumbrineris longifolia(14.0%), Heteromastus filiformis(3.6%), a mussel Mytilus edulis, and an amphipod crustacean Corophium sinense. The abundance and biomass in the western part of the bay were lower than in the channel regions and mouth of the bay. The community indices showed the same trend in the spatial distribution with the abundance and species richness. The study area can be divided into seven station groups; five station groups in the eastern part, two groups in the channel and open mouth part of the bay.

A Quantitative Analysis of the Spatial Agglomeration Pattern among the Korean Cities (한국 도시들의 공간집적 패턴에 대한 계량분석)

  • Sohn, Jungyul
    • Journal of the Korean Geographical Society
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    • v.48 no.1
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    • pp.56-71
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    • 2013
  • The purpose of this study is to examine the spatial distributional characteristics of industries among the Korean cities and to conduct industry classification using the findings. For this purpose, 82 cities in Korea are investigated with respect to 15 industrial sectors. In the analysis, concentration of and association between industries are recognized using both geographic and non-geographic measures. In order to measure concentration and association, locational Gini coefficient, Moran's I, correlation coefficient, and bivatiate Moran are used and 15 industrial sectors are classified based on these estimates. The findings reveal that the chemical sector shows strong geographic and non-geographic concentrations while the assembly, machinery and electronics sector only shows a strong geographic concentration. Printing and publishing, wholesale, and business services show a strong non-geographic association with other sectors. The remaining ten sectors show no explicit distribution patterns among cities. This study contributes to providing the methodology that analyzes the spatial distribution patterns of industries in a comprehensive way and is able to provide useful information in implementing industrial location policies including industrial clusters.

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A Study on the Spatial Analysis of Walfare in Pusan, Korea (社會指標에 依한 福祉不均衡의 空間的 硏究)

  • Bae, Mee-Ae
    • Journal of the Korean Geographical Society
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    • v.32 no.1
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    • pp.91-112
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    • 1997
  • This paper is mainly concerned with an understanding of spatial pattern of welfare by social indicators; thus an attempt for a social research is made to clarify spatial characteristics of welfare in Pusan through local welfare approach. The use of objective and subjective indicators simultaneously helps supplement the weakness which each of this indicators holds. The welfare level in Pusan showed various characteristics in the whole study area and in the all welfare sectors. Especially, the differences between objective and subjective welfare are found in the whole city. If the redistributional strategy is given to the priority among the welfare policies, it may be expected that the welfare level will be more equally distributed in Pusan.

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Spatial Distribution Patterns of Macrobenthic Communities during Winter and Summer in the Masan Bay Special Management Area, Southern Coast of Korea (남해특별관리해역인 마산만에서 동계 및 하계에 출현하는 대형저서동물군집의 공간분포 양상)

  • Choi, Jin-Woo;Seo, Jin-Young;Lee, Chang-Hoon;Ryu, Tae-Kwon;Sung, Chan-Gyung;Han, Gi-Myung;Hyun, Sang-Min
    • Ocean and Polar Research
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    • v.27 no.4
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    • pp.381-395
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    • 2005
  • The spatial distributions of macrobenthic communities in Masan Bay were investigated during summer and winter, 2004. A total of 104 species were sampled with mean density of $448ind./m^2$ and biomass of $77.1g/m^2$ in winter. In summer, a total of 107 species occurred with $485ind./m^2$ and a biomass of $94.5g/m^2$. The most dominant species in winter were Paraprionospio pinnata (24.2%) among polychaetous worms and Theora fragilis (14.1%) among molluscs, but they were replaced in summer by Prionospio chirrifera (20.4%) and Lumbrineris longifolia (14.5%). The difference in species composition and abundance of benthic communities between the two seasons was due to the hypoxia in the bottom layer of the inner bay during summer, which defaunated the macrofauna of the sediments. In the winter when DO concentration increased to normoxia, the pelagic larvae of benthic fauna settled in the soft sediments, but there was a spatial gradient in values of total biomass, density, and H' and benthic pollution index (BPI): higher values were found toward the mouth of the bay. The multivariate analyses like the cluster analysis and MDS ordination showed that Masan Bay could be divided into two or four stational groups in winter and summer whether the hypoxia occurred or not. Group I consisted of sites at the inner bay and central area and Group II, sites at the bay mouth. In summer the inner bay area could be further divided into the shallow impoverished area and the deeper abiotic one.

Environmental Equity Analysis of the Accessibility of Urban Neighborhood Parks in Daegu City (대구시 도시근린공원의 접근성에 따른 환경적 형평성 분석)

  • Seo, Hyun-Jin;Jun, Byong-Woon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.4
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    • pp.221-237
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    • 2011
  • This study aims to investigate the environmental equity of the accessibility to urban neighborhood parks in the city of Daegu. The spatial distribution of urban neighborhood parks was explored by spatial statistics and the spatial accessibility to them was then evaluated by both minimum distance and coverage approaches. Descriptive and inferential statistics such as proximity ratio, Mann Whitney U test, and logistic regression were used for comparing the socioeconomic characteristics over different accessibilities to the neighborhood parks and then testing the distributional inequity hypothesis. The results from the minimum distance method indicated that Dalseo-gu had the best accessibility to the neighborhood parks while Dong-gu had the worst accessibility. It was apparent with the coverage method that Dalseo-gu had the best accessibility whereas Dong-gu and Nam-gu had the worst accessibility to the neighborhood parks at 500m and 1,000m buffer distances. There existed the spatial pattern of environmental inequity in old towns with respect to population density and the percentage of people under the age of 18. The spatial pattern of environmental inequity in new towns was explored on the basis of the percentage of people over the age of 65, the percentage of people below the poverty level, and the percentage of free of charge rental housing. These results were closely related to the development process of urban parks in Daegu stimulated by the quantitative urban park policy, urban development process, and residential location pattern such as permanent rental housing and free of charge rental housing. This study further extends the existing research topics of environmental justice related to the distributional inequity of environmental disamenities and hazards by focusing on environmental amenities such as urban neighborhood parks. The results from this study can be used in making the decisions for urban park management and setting up urban park policy with considering the social geography of Daegu.

Social Geography of Poverty and Social Welfare Services (빈곤계층과 사회복지서비스의 공간적 연계성)

  • Bae, Mi-Ae
    • Journal of the Korean Geographical Society
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    • v.42 no.2 s.119
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    • pp.177-195
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    • 2007
  • The central aim of this paper is to identify the distributional pattern of poverty and to investigate the spatial relationship between poverty and welfare service providers in Busan, Korea. It is intended to explain how the relationship of service-dependency between impoverished people and social welfare services leads to uneven social geography. Welfare services controlled by public or private agencies may support the impoverished people in different ways, generating social outcomes. By exploiting the spatial variations in the incidence of poverty and the provisions of social welfare services, this paper is to understand the dynamics of the geography of poverty from a local scale so that it can help us understand how various governmental and nongovernmental area-based service providers are spatially uneven when they are compared to the distribution of service dependency group such as impoverished people. From this research, it is finally argued that the implications of locational interdependence between such needed groups and social welfare services for their support demand a paradigm for urban social geography that centers on the changing welfare provision structure and the linkages between population and service-provision.