• Title/Summary/Keyword: Non-Metric Multidimensional Scaling

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Correlation Between Vegetation Structure and Environmental Factors of Corylopsis coreana Uyeki Habitats (히어리 자생지 식생구조와 환경요인 간 상호관계)

  • Park, Byeong-Joo;Heo, Tae-Im;Cheon, Kwangil
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.26 no.4
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    • pp.1-16
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    • 2023
  • The purpose of this study is to understand the vegetation structure of the Corylopsis coreana habitats in South Korea and their correlation with environmental factors, in order to provide basic data for preparing conservation. A total of 40 vegetation survey plots were established in around Southern region, Gangwon-do and Gyeonggi-do Province. The cluster analysis revealed four distinct clusters: Quercus mongolica-Pinus densiflora (QmPd), Castanea crenata (Cc), Quercus mongolica (Qm), and Pinus koraiensis (Pk). Among them, the QmPd cluster was selected as the representative community. Soil texture analysis that most areas consisted of loamy soil and were distributed on the northern aspects. The plantation, represented by Pk, exhibited a high content of exchangeable aluminum (5.227±0.342 mg/kg), suggesting the need for soil improvement and monitoring in these habitats. The canopy openness (forest gap) ranged from 11% to 21%, indicating a relatively closed canopy in many survey plots. Non-metric multidimensional scaling analysis indicated heterogeneous species composition between the QmPd cluster and the Pk cluster (total R2 = 0.608).

Effect of geography and altitude on the community characteristics of epigeic spiders in rice field levees (지형 및 고도에 따른 토양성 논거미 군집특성)

  • Eo, Jinu;Kim, Myung-Hyun;Kim, Min-Kyeong;Choi, Soon-Kun
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.594-602
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    • 2020
  • This study investigated the effect of geography and altitude on epigeic spider communities in rice field levees in Jeollabuk-do. Spider communities in the mountainous and plain areas were compared to determine the effect of geography on the cultivation periods. The effect of altitude was compared between the Jeongeup and Jangsu areas during non-cultivation periods. Analysis using nMDS (non-metric multidimensional scaling), MRPP (multiple response permutation procedure), and ANOSIM (analysis of similarity) revealed differences in spider community structures between the two types of study areas. Lycosidae predominated at the family level, and its abundance was greater in the mountainous area than in the plains area. The total abundance did not differ between the two areas with different altitudes, but the abundance of three Pardosa species was greater at lower altitudes than at higher altitudes. Geography and altitude had a minimal effect on species richness and diversity indices at the community level. However, several Lycosidae species showed species-specific responses to both geography and altitude in the rice fields.

The Habitat Classification of mammals in Korea based on the National Ecosystem Survey (전국자연환경조사를 활용한 포유류 서식지 유형의 분류)

  • Lee, Hwajin;Ha, Jeongwook;Cha, Jinyeol;Lee, Junghyo;Yoon, Heenam;Chung, Chulun;Oh, Hongshik;Bae, Soyeon
    • Journal of Environmental Impact Assessment
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    • v.26 no.2
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    • pp.160-170
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    • 2017
  • The purpose of this study is to perform clustering of the habitat types and to identify the characteristics of species in the habitat types using mammal data (70,562) of the 3rd National Ecosystem Survey conducted from 2006 to 2012. The 15 habitat types recorded in the field-paper of the 3rd National ecosystem survey were reclassified, which was followed by the statistical analysis of mammal habitat types. In the habitat types cluster analysis, non-hierarchical cluster analysis (k-means cluster analysis), hierarchical cluster analysis, and non-metric multidimensional scaling method were applied to 14 habitat types recorded more than 30 times. A total of 7 Orders, 16 Families, and 39 Species of mammals were identified in the 3rd National Ecosystem Survey collected nationwide. When 11 clusters were classified by habitat types, the simple structure index was the highest (ssi = 0.07). As a result of the similarities and hierarchies between habitat types suggested by the hierarchical clustering analysis, the residential areas were the most different habitat types for mammals; the next following type was a cluster together with rivers and coasts. The results of the non-metric multidimensional scaling analysis demonstrated that both Mus musculus and Rattus norvegicus restrictively appeared in a residential area, which is the most discriminating habitat type. Lutra lutra restrictively appeared in coastal and river areas. In summary, according to our results, the mammalian habitat can be divided into the following four types: (1) the forest type (using forest as the main habitat and migration route); (2) the river type (using water as the main habitat); (3) the residence habitat (living near residential area); and (4) the lowland type (consuming grain or seeds as the main feeding resource).

Trend of temporal change in moth communities in forests of the agricultural landscape of southwestern South Korea (한국 서남부 농촌 경관 내 숲에 서식하는 나방 군집의 시간적 변화 양상)

  • Choi, Sei-Woong;Kim, Nang-Hee;Shin, Bora;Lee, Jae-Young;Jang, Beom-Jun
    • Korean Journal of Environmental Biology
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    • v.37 no.3
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    • pp.426-432
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    • 2019
  • The aim of the present study was to investigate the temporal changes of moth communities in two forest types of the agroecosystem in the southwestern part of Korea, an isolated hillock forest and a continuous mountain forest. Temporal changes in the numbers of moth species and individuals at both forests showed no significant difference, although the numbers of individuals in the isolated hillock forest were decreased. The relationship between changes in moths and body size based on wingspan revealed that the larger moths decreased more in the isolated hillock forest, whereas no effect of body size on change of moths was observed in continuous mountain forest samples. Non-metric multidimensional scaling resulted in the grouping of moth communities by forest types and 10-year time intervals. In the future, long-term monitoring is needed to track the changes in moth communities in agroecosystems. Additionally, we need to investigate the effect of other ecological variables on changes in moth diversity.

Distributional Uniqueness of Deciduous Oaks(Quercus L.) in the Korean Peninsula (한반도 하록 참나무류의 분포 특이성)

  • Kim, Yun-Ha;Kim, Jong-Won
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.20 no.2
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    • pp.37-59
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    • 2017
  • The Korean peninsula belongs to the temperate forest biome dominated by many deciduous oaks. We quantitatively and qualitatively studied vertical and horizontal distributions and habitat characteristics on the major oak species such as Quercus mongolica, Q. serrata, Q. variabilis, Q. dentata, Q. aliena and Q. acutissima. A total of 5,278 samples were analyzed with a species coverage and 6 principal environmental variables extracted from public database of nationwide natural environment survey. Correlation analysis was accomplished by the CANOCO using Canonical Correspondence Analysis and the Pearson correlation coefficient using PASW Statistics. The hierarchical distribution tendency of six oaks was finalized using the Goodman-Kruskal lambda coefficient of non-metric multidimensional scaling by SYN-TAX 2000. The utmost factor on the distributional segregation of oak species was the elevation, i.e. temperature. Q. serrata and Q. mongolica show clearly a diametrical distribution patterns with zonal distribution. Q. variabilis was determined as a thermophilic and xerophilous species that is a component of not only natural pseudo-climax forest but also secondary forest. The highest frequency of the dominant forest was found Q. mongolica. Whereas, Q. serrata showed the highest frequency of individual tree but the relatively lower frequency of dominant forest, which is resulted from the original habitat loss. By the benefit of the traditional Soopjeong-E, Q. acutissima dominant forests were remained rather largely. Individuals of Q. dentata occurred horizontally nationwide, but its dominant forest was the poorest. Dominant forest of Q. aliena, which is a natural vegetation, was the most rare due to a limited potential habitat.

Annual Variations in Community Structure of Mesozooplankton by Short-term Sampling in Jangmok Harbor of Jinhae Bay (진해만의 장목항에서 단주기 샘플링에 의한 중형동물플랑크톤 군집의 연변동)

  • Hwang, Ok-Myung;Shin, Kyoung-Soon;Baek, Seung-Ho;Lee, Woo-Jin;Kim, Su-Am;Jang, Min-Chul
    • Ocean and Polar Research
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    • v.33 no.3
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    • pp.235-253
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    • 2011
  • The annual variation of mesozooplankton community in the Jangmok harbor of Jinhae Bay was studied in relation to environmental variables. Sampling was carried out weekly from January to December 2009. During the study periods, mesozooplankton community consisted of 44 taxa and the annual mean abundance was 8308 inds. $m^{-3}$. The maximum abundance was observed to be 50043 inds. $m^{-3}$ in August and the minimum in April with 1013 inds. $m^{-3}$. Of these, Penilia avirostris, cirripedia larvae, Evadne tergestina, Acartia omorii, Oikopleura s, Paracalanus parvus s. l., Eurytemora pacifica, Podon s, Oithona s, and Acartia steueri were observed as dominant species in Jangmok bay and they also contributed to 79% of total mesozooplankton. According to non-metric multidimensional scaling (nMDS) and cluster analysis based on the mesozooplankton community data from each season, the community was divided into three groups. The first group included appearence species in winter and spring season, which is mainly dominated the copepod such as A. omorii and E. pacifica. The second and third group was composed with observed species in summer and autumn, respectively. Based on the SIMPER (similarity percentages), P. avirostris in summer and cirripedia larvae in autumn were significantly dominated. Our results indicate that although the mesozooplankton abundances in Jangmok harbor fluctuated abruptly, its annual variation was strongly influenced by water temperature.

Polychaete Community Structure from Inshore and Offshore of Lake Shihwa (Korea) in March, 2008 (2008년 3월 시화방조제 내측과 외측해역에서 저서다모류 군집구조)

  • Jung, Rae-Hong;Choi, Min-Kyu;Yoon, Sang-Pil;Lee, Won-Chan;Choi, Hee-Gu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.45 no.1
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    • pp.56-64
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    • 2012
  • Polychaete community structure and its spatial distribution was investigated in 2008 from inshore and offshore of Lake Shihwa, Korea, in order to evaluate status of the benthic environment according to construction of the dike and the water gate. In the present study, the number of species, density, and diversity of polychaete community in inshore was significantly different from those in offshore. The density of polychaete community in offshore increased with the number of species whereas the diversity in inshore increased with the number of species. Dominant species in offshore were 13 species, higher than 1% of the total polychaete individuals. Heteromastus filiformis, known as the most dominant species before the construction of the dike, was the most dominant species in offshore, which collectively account for 54% of the total polychaete individuals. In inshore, the seven species were dominant, higher than 1% of the total individuals. Lumbrineris longifolia, Polydora sp., Capitella capitata, Pseudopolydora paucibranchiata, known as pollution tolerant species, contributed to higher than 75% of the total individuals in inshore. Multivariate statistical analyses, non-metric multidimensional scaling, showed apparent difference in polychaete community structure between inshore and offshore, and also difference between inner sites and outer sites of inshore around the water gate. Sediment characteristics (total organic carbon and nitrogen, ignition loss, and acid volatile sulfide) measured in this study also supported to this result. Therefore, this indicates that the offshore provides better benthic environments for polychaete habitation than the inshore, and the inshore around the water gate shows improving benthic environment, compared to the inner inshore.

Statistical Relations between Benthic Macroinvertebrate Distribution and Water Quality at Pungyeongjeong Stream in the Urban Region (도심하천인 풍영정천에서 저서성 대형무척추동물 분포와 수질과의 통계적 관계 분석)

  • Yoon, Sang-Hoon;Yang, Yoon-Cheol;Seo, Gwang-Yeob;Cho, Young-Gwan
    • Journal of Korean Society on Water Environment
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    • v.34 no.2
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    • pp.164-172
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    • 2018
  • This study aims to determine the community patterns of benthic macroinvertebrates and analyze the relationship between the communities and the water quality in the Pungyeongjeong Stream. We collected the samples four times by season. The number of species was 28 and the dominant species were Cheumatopsyche brevilineata, Hydropsyche kozhantschikovi, Baetis fuscatus, Chironomidae spp., and so on. The range of the dominant index was 0.54 to 0.93 and the mean was 0.77. The range of the diversity index was 0.94 to 2.54, and of the mean index it was 1.75. The ratio of filtering-collectors and clingers got lower, but the ratio of gathering-collectors and sprawlers got higher as collection progressed from the upper stream to the lower stream. The results of the Pearson correlation analysis showed COD, SS, TOC and total coliforms were highly related with biotic indices of benthic macroinvertebrates. The results of cluster analysis and non-metric multidimensional scaling ordination showed that the survey sites and periods were divided into three groups. The survey sites were divided into upper stream and middle-lower stream. The survey periods were divided into winter season and other seasons. Distribution of benthic macroinvertebrates showed some characteristics according to various influence factors; however long-term and regular investigations were thought to need analysis and prediction with various statistical methods.

Seasonal Changes of Zooplankton Communities along the Coast of Geumo Arichipelago, Yeosu (여수 금오열도 연안에서 동물플랑크톤 군집의 계절 변동)

  • Oh, Hyun-Ju;Moon, Seong Yong;Soh, Ho Young
    • Korean Journal of Environmental Biology
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    • v.31 no.3
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    • pp.192-203
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    • 2013
  • To understand the seasonal changes in the zooplankton community, we investigated their occurrence patterns and environmental factors during four seasons at 9 stations along the coast of Geumo Archipelago, Yeosu. A total of 44 taxa were sampled, with an abundance ranging from 15~$28,183inds.\;m^{-3}$, among which Noctiluca scintillans predominented. Noctiluca scintillans, Paracalaus parvus s. l., Acartia (Acartiura) omorii, Oithona spp., Aidanosagitta crassa, dedapods larvae, copepods nauplii, and copepodites were the most abundant taxa detected. Species diversity of zooplankton was high in autumn and winter, but it was relatively low in summer and spring. Non-metric multidimensional scaling (nMDS) revealed significant differences in the structures of the zooplankton community among the seasons. Our results showed that the seasonal variation in zooplankton community along the coast of Guemo Archipelago, Yeosu were attributable to seasonal changes in temperature, salinity, and Chl. a concentration. Additionally, this particularly study area might have been specifically influenced by occurs of the neritic species.

Distribution Patterns of Sandy Bottom Macrobenthic Community on the Hupo Coastal Area, in the East Sea of Korea (동해 후포주변 사질조하대에 서식하는 대형저서동물군집의 분포특성)

  • Paik, Sang-Gyu;Kang, Rae-Seon;Jeon, Jae-Ok;Lee, Jae-Hac;Yun, Sung-Gyu
    • Ocean and Polar Research
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    • v.29 no.2
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    • pp.123-134
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    • 2007
  • Distribution patterns of sandy bottom macrobenthic communities were studied around the Hupo coastal area. The seasonal surveys were conducted at 15 chosen sites within a depth range of 10 to 50 m along 10 km of the coastline using a Smith-McIntyre grab $(0.05\;m^2)$ in 2005. Overall depth distribution following the direction of the offshore become deeper parallel to the coastline. A total of 319 macrobenthic species were sampled with a mean density of $1,972\;ind./m^2$, and mean biomass was 82.5 wet-weight $g/m^2$. The major individual-dominant species were three polychaetes Spiophanes bombyx ($436\;ind./m^2$), Scoletoma longifolia ($250\;ind./m^2$) and Magelona japonica ($170\;ind./m^2$), and bivalve Adontorhina subquadrata ($73\;ind./m^2$). Cluster analysis and non-metric multidimensional scaling (nMDS) analysis based on Bray-Curtis similarity identified 2 major station groups which corresponded to macrobenthic faunal assemblages and their characteristic species. In addition, environmental conditions were significantly different between station groups. Group I contained mostly 20 and 50 m deep sites and was associated with sandy mud. Group I was characterized by high abundance of S. bombyx, S. longifolia, A. subquadrata. It was divided into two sub-groups (I-I and I-II) in relation to depth. Sub-group I-I was associated with deeper sites than sub-group I-II. Group II included mostly inshore area shallower than 15 m and was associated with coarse and medium sand. Group II was characterized by Lumbrinerides hayashii and Urothoe grimaldii japonica.