• Title/Summary/Keyword: detrended correspondence analysis

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Plant diversity of the pads of electric towers along the deltaic Mediterranean coast of Egypt

  • Kamal Shaltout;Hani Beshara;Yassin Al-Sodany;Ahmed Sharaf, El-Din;Ragab El-Fahar
    • Journal of Ecology and Environment
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    • v.47 no.3
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    • pp.63-74
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    • 2023
  • Background: Comparing with the several types of infrastructures, linear infrastructures are known to facilitate the spread of undesirable species in ecosystems. Recently, some new man-made habitats (e.g., gravel pads of the high-voltage towers, solid wastes and sewage habitats) were established along the Deltaic Mediterranean coast of Egypt as a result of the construction of the E-W coastal international highway. The current study evaluates the floristic composition associated with the pads of high-voltage towers that had been constructed for stabilizing the power line towers in the North Nile Delta. Plant cover was measured for 22 randomly stand. Results: Eighty-four species were recorded, of which 35 are perennials (41.6%), 2 biennials (2.3%) and 47 annuals (56.0%) belonging to 23 families. The largest families were Asteraceae (16 species), Poaceae (15 species), Chenopodiaceae (12 species), and Fabaceae (7 species). Ten aliens (10.7%) out of the 84 species were recorded. Therophytes have the highest percentage (58%), followed by hemicryptophytes (14%), chamaephytes (11%). Six vegetation groups were recognized in the study area after the application of two way indicator species analysis (TWINSPAN), Arthrocnemum macrostachyum, Phragmites australis, and Mesembryanthemum nodiflorum have the highest presence percentage. Both of Salsola cyclophylla and Solanum villosum were recorded for the first time in North Nile Delta. Natural habitat had the highest α-diversity, but the lowest β-diversity (4.9, 15.4), while gravel pads had the reverse (2.7, 30.8). Some species which are native to the desert habitats (e.g., Rumex pictus, Salsola kali, and Carthamus tenuis) were able to invade the North Nile Delta. Conclusions: Habitat of gravel pads is an expressing form about the intense of disturbance in Deltaic Mediterranean coast of Egypt. More of efforts should be carried out to avoid more human disturbances that creating as ruderal habitats which open the gate to invasive species in the flora of North Nile Delta.

Microalgal diversity in response to differential heavy metals-contaminated wastewater levels at North Nile Delta, Egypt

  • Maha Youssef Kamal Elmousel;Eithar El-Mohsnawy;Yassin Mohamed Al-Sodany;Eladl Galal Eltanahy;Mohamed Ali Abbas;Awatif Saad Ali
    • Journal of Ecology and Environment
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    • v.47 no.3
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    • pp.157-167
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    • 2023
  • Background: The most hazardous wastewater sources in the northern part of the Middle Nile Delta, Egypt; receiving a massive amount of agricultural, industrial, and sewage drainage are Kitchener drain which is one of the tallest drainage systems, and Burullus Lake which represents the 2nd largest Egyptian coastal lake. Results: The current work is to determine the abundance and frequency of cyanophytes, chlorophytes, and bacillariophytes and the correlation between them and environmental abiotic components. Among sixty nine microalgal species, 19 species are belong Cyanophyta, 26 belong Chlorophyta and 24 belong Bacillariophyta. Genus Scenedesmus (Chlorophyta) was the most abundant in the study area (13 species), followed by Genus Oscillatoria (9 species) and Genus Navicula (7 species). Nostoc muscorum and Chlorella vulgaris were the most common and recorded in all sites (100% of the locations) under study. The application of the two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis revealed agglomerating of 4 groups (communities) at 4th level of classification and reasonable segregation between these groups. Zinc, cadmium and lead were showed the highest levels (0.26±0.03, 0.26±0.06, and 0.17±0.01 ppm, respectively). Conclusions: The correlation analysis between water and community variables indicated a high negative correlation of total algae richness with nickel (r = -0.936, p < 0.01). Cyanophyta and Bacillariophyta were correlated negatively (r = -0.842, p < 0.01). However, Chlorophyta showed a negative richness with each of Ni and Pb (r = -0.965, -0.873, respectively) on one hand and a high positive correlation was revealed (r = 0.964) with all environmental variables on the other hand.

Vegetation Structure of Urban Forests on Mt. Goehwa, Sejong-Si (세종시 괴화산 도시숲의 식생구조)

  • Hyeon-Hwa Kim;Jeong-Eun Lee;Sung-Yeon Lee;Da-Eun Park;Chung-Weon Yun
    • Journal of Korean Society of Forest Science
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    • v.113 no.1
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    • pp.51-65
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    • 2024
  • Phyto-sociological methods were used in this study to assess the vegetation structure of a forest stand at Mt. Goehwa in Sejong-Si with the aim of providing vegetation information for urban forest utilization and management plans. The actual forest vegetation was classified into two types of community groups (Quercus serrata-Lindera obtusiloba and Coreopsis lanceolata community groups) at the highest hierarchical level. The Q. serrata-L. obtusiloba community group was classified into six units, which included artificial forest and natural forest vegetation. Artificial forests were classified into three communities (Pinus rigida, Castanea crenata, and Robinia pseudoacacia), whereas natural forests were classified into three communities (Quercus variabilis, Quercus acutissimaa, and Pinus densiflora). The Coreopsis lanceolata community group, which exhibited vegetative characteristics of urban forest edge areas, was categorized into four units. The urban forest edges were classified into four communities (Indigofera bungeana, Lespedeza bicolor, Amorpha fruticosa, and Lespedeza cuneata). Accordingly, the vegetation structure of Mt. Goehwa was categorized into 10 vegetation unit systems. An importance value analysis showed the highest importance value for C. crenata at 6.7%, followed by P. rigida at 6.4%, and R. pseudoacacia at 6.3%, indicating that the ecological impact of plantation species can be significant on Mt. Goehwa. A community coefficient of similarity analysis revealed that the artificial and natural forests had similar species compositions; however, both forests differed from the urban forest edge. This variation was further confirmed by Detrended correspondence analysis(DCA), with similar results. Canonical correspondence analysis(CCA) showed that the artificial forest and natural forest community types were positively correlated with altitude, bare rock, and the present species. By contrast, the urban forest edge community types were negatively correlated with these factors.

The Analysis of Vegetation-Environment Relationships of Mt. Jungwangsan by TWINSPAN(Two-Way Indicator Species Analysis) and DCCA(Detrended Canonical Correspondence Analysis) Ordination (TWINSPAN과 DCCA에 의한 중왕산(中旺山)의 삼림군집(森林群集)과 환경(環境)의 상관관계(相關關係) 분석(分析))

  • Song, Ho Kyung;Kwon, Ki Won;Lee, Don Koo;Jang, Kyu Kwan;Woo, In Shik
    • Journal of Korean Society of Forest Science
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    • v.81 no.3
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    • pp.247-254
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    • 1992
  • Vegetational data obtained from 50 quadrats of Mt. Jungwangsan area were analysed by applying two multivariate methods : two-way indicator species analysis(TWINSPAN) for classification and detrended canonical correspondence analysis(DCCA) for ordination. DCCA technique allowed to extract the ordination axes that could be related to 15 environmental factors. The forest vegetation in Mt. Jungwangsan was classified into Quercus mongolica-Tilia amurensis, Quercus mongolica-Rhododendron schlippenbachii, Quencus mongolica-Kalopanax pictus, Quercus mongolica-Carpinus cordata, Quercus mongolica-Cornus controversa, Betula costata, Fraxinus mandshurica, and Ulmus laciniata communities according to the TWINSPAN. The relationships between the distribution of dominant species of forest vegetation and soil condition in Mt. Jungwangsan were investigated by analyzing elevation and soil nutrition gradient. Ulmus laciniata, Betula costata, and Fraxinus mandshurica forest were distributed in a ravine of the low elevation and in the good nutrition area of $Mg^{{+}{+}}$, total nitrogen, and $Ca^{{+}{+}}$, Quercus mongolica groups in the high elevation and in the poor nutrition area. Quercus mongolica-Kalopanax pictus forest of Quercus mongolica groups was distributed in the high elevation and in the good nutrition area of $Ca^{{+}{+}}$, C.E.C., $Mg^{{+}{+}}$, and total nitrogen, Quercus mongolica-Rhododendron schlippenbachii forest in the low elevation and poor nutrition area. Quercus mongolica-Carpinus cordata forest and Quercus mongolica-Cornus controversa forest were distributed in the medium elevation and medium nutrition area. The two dominant factors influencing community distribution were elevation and topography.

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On Ordination, Clustering and Neighbourhood Effects in the Semi-natural Pine Stands in Central Korea (반자연 소나무 숲에 있어서의 Ordination 미분류 및 인근 효과 ( 경쟁 ) 에 대하여)

  • Oh, Kye-Chil;Lee, Kun-Seop
    • The Korean Journal of Ecology
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    • v.12 no.2
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    • pp.83-108
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    • 1989
  • To discern general tendency in relatively pure even-aged pine stands, to group the stands and to perceive neighbourhood effects a total of 39 sites of pine stand was surveyed from nearby Seoul (12 sites), Chunsung, Kangwon (13 sites) and Sosan, Chungnam (14 sites), for herb and shrub species 32, 19; 37, 19 and 41, 14 in the respective areas from September 1987 to July 1988. In terms of detrended correspondence analysis (DECORANA), the stands were subjected to ordinate with 16 physical variables and the vegetational variables. The resource ratio (N:P, N:K, P:K) as physical variables also was tried out in the DECORANA as well as independent variable (N.P.K). The outcome did not show any meaningful difference. It is suggested that there seems to be no apparent interaction among the elements in the study. Three vertical vegetation componeent, that is, tree layer, shrub layer, herb layer were subjccted to DECORANA independently, pairwisely and as a whole (a total 7 combinations). Of those analysis herb layer trial alone seems to indicate relatively clearer differences among the physical variables. In the stands nearby Seoul first axis indicated soil field capacity and exchangeable cations (K, Ca and Na) and second axis did not show any tendency. For the Chunsung stands first axis also revealed soil field capcity and amount of arganic matter and second axis showed amount of exchangeable cation (K, Ca and Na), In the Seosan 1st axis indicated pH and exchangeable cations (K, Ca and Na). For the 39 sites 4 clusters in terms of herb layer might be defined: Peucedanum terebinthaceum-Cymbopogon tortilis-Polygala japonica-Festuca ovina (1); Atractylodes japonica-Patrina scabiosaefolia (2); Potentilla fragarioides-Atractylodes (3); and Cymbopogon tortilis (4). In the neighbourhood effects study in terms of the basal area distribution, Thiessen polygon area and Gini coefficient for the Pinus thunbergii stands of Seosan the Thiessen polygon area approach seems to indicate earlier (30 years old) neighbourhood effect than the others (45 years).

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Species composition of the catches collected by trammel net in the coastal waters off Ulleungdo of Korea (울릉도해역에서 삼중자망에 의한 어획물의 종조성)

  • CHUNG, Sangdeok;CHA, Hyung Kee;LEE, Jae Bong;LEE, Hae Won;YANG, Jae Hyeong
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.51 no.4
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    • pp.567-575
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    • 2015
  • Species composition in the coastal waters off Ulleungdo of Korea were examined based on catches bimonthly collected by trammel net in 2013. A total of 711 individuals and 181.9 Kg were caught and catches were composed of 4 classes 15 orders 27 families 52 species including 44 Pisces, 4 Gastropoda, 3 Cephalopoda, and 1 Echinodermata. The dominant species in biomass were File fish (Thamnaconus modestus), Atka mackerel (Pleurogrammus azonus), and Greenling (Hexagrammos otakii). Data were summarized using hierarchical cluster analysis (HCA) and detrended correspondence analysis (DCA) to examine similarity in species composition for each month, and community structure in Ulleungdo was divided into two groups. Community structures in February, April and December with low temperature and well-mixed surface water were distinguished from those in June, August and October with high temperature and strong stratification, which could be attributed to temporal changes in dominant species. Atka mackerel and Spear squid mainly caught in February and April, disappearing in June, August and October, and File fish outburst was shown in October. Because the water off Ulleungdo has been under low human pressure, it could be a good case study to elucidate effects of climate change on community structure and ecosystem in the East sea. Continuous surveys and further studies are required to demonstrate migration route and distribution of dominant species and long-term changes in community structure in the water of Ulleungdo.

Studies on the Vegetational Landscape Structure and Administration Planning of the Royal Tomb(I) - Successional Trends of Plant Community of Donggu Royal Tomb - (왕릉의 식생경관구조 및 관리대책에 관한 연구(I) - 동구릉 식생군집의 천이 -)

  • 이경재;오구균;전용준
    • Journal of the Korean Institute of Landscape Architecture
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    • v.16 no.1
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    • pp.13-26
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    • 1988
  • ^x This study was executed to analyze the vegetational landscape structure of Donggu Royal Tomb forest by four kinds of ordination techniques(polar, principal component analysis, reciprocal averaging, and detrended correspondence analysis) and comparison of the couple photographs between 1920s and 1987. Thirteen sites were sampled with clumped sampling method in June of 1987 and five quadrats were examined in each site. The result of this study can be summarized as follows. 1. Environmental impact grade 3,4 and 5 area covered 16.11ha and these area should be restored by the input of human energy because self - refair seemed to be impossible. 2. Pinus densiflora community of actual vegetation covered 8.2%, Alnus japonica community 5.7% and quercus aliena community 15.8% of the surveyed area(73.3ha). And afforested vegetation including Pinus koraiensis, Pinus rigida, Alnus hirsuta and Robinia pseudoacacia covered 27.0%. 3. Donggu Royal Tomb forest was divided by Pinus densiflora, P. densiflora-Quercus aliena, Alnus japonia - Q. aliena and A. japonica community. DCA was the most effective method of this study. 4. DCA ordination were showed that succesional trends of tree species seem to be from Pinus densiflora through Prunus sargentii, Quercus serrata, Quercus aliena to Carpinus laxiflora in P. densiflora community and from Alnus japonica through Acer ginnala to Q. aliena in A. japonica community of the upper layer and from Rosa multiflora, Symplocos chinensis for. pilosa, Zanthoxylum schiniflolium through Rhus trichocarpa, Styrax japonica, Rhododendron scilippenbachii to Viburum erosum, Lindera obtusiloba in the middle layer. 5. By the comparsion of the couple photographs beween 1920s and 1987, we can recognize the change of historical landscape composed by P. densiflora and A. japonica community and those community is succeed to Q. aliena.

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Colonization and community changes in benthic macroinvertebrates in Cheonggye Stream, a restored downtown stream in Seoul, Korea

  • Shin, Il-Kwon;Yi, Hoon-Bok;Bae, Yeon-Jae
    • Journal of Ecology and Environment
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    • v.34 no.2
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    • pp.175-191
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    • 2011
  • Colonization patterns and community changes in benthic macroinvertebrates in the Cheonggye Stream, a functionally restored stream in downtown Seoul, Korea, were studied from November 2005 to November 2007. Benthic macroinvertebrates were quantitatively sampled 15 times from five sites in the stream section. Taxa richness (59 species in total) increased gradually over the first year, whereas the density revealed seasonal differences with significantly lower values in the winter season and after flood events. The benthic macroinvertebrate fauna may have drifted from the upstream reaches during floods and from the Han River, arrived aerially, or hitchhiked on artificially planted aquatic plants. Oligochaeta, Chironommidae, Psychodidae, and Hydropsychidae were identified as major community structure contributors in the stream. Swimmers and clingers colonized relatively earlier in the upper and middle reaches, whereas burrowers dominated particularly in the lower reaches. Collector-gatherers colonized at a relatively early period throughout the stream reaches, and collector-filterers, such as the net-spinning caddisfly (Cheumatopyche brevilineata), predominated in the upper and middle reaches after a 1-year time period. Cluster analyses and multi-response permutation procedures demonstrated that the Cheonggye Stream shares more similarities with the Jungnang Stream than with the Gapyeong Stream. Detrended correspondence analysis and nonmetric multidimensional scaling demonstrated that physical environmental factors (depth, current velocity, dissolved oxygen, and pH) as well as nutrients (total nitrogen and total phosphorous), water temperature, and conductivity could affect the distribution of benthic macroinvertebrates in the study streams.

Contrasting Zooplankton Community Structure in Sandusky Bay and Lake Erie (Sandusky Bay 와 Lake Erie 의 상이한 동물 플랑크톤 군집의 구조에 대하여)

  • Hwang, Soon-Jin;Robert T. Heath;Ralph J. Garono
    • The Korean Journal of Ecology
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    • v.19 no.6
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    • pp.543-562
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    • 1996
  • Zooplankton community structure and the factors correlated with community differences were examined in sandusky Bay (SB) and the open water of Lake Erie (LE, U.S.A.). SB zooplankton communities differed from those in LE by having a greater rotifer density and species richness. Keratella spp., Brachionus spp., and Pompholyx complanata dominated SB rotifers; Brachionus and Pompholyx were rarely seen in LE. Of 19 rotifer species observed, nine species were found only at SB sites. Ordination of zooplankton species abundance by detrended correspondence analysis (DCA) showed an overlap between SB and LE sites, but indicated a portion of the space that was occupied by only SB communities. The seasonal trajectories of zooplankton dynamics in the ordination space at SB sites differed from that of LE. The zooplankton most important in forcing site separation along a DCA Axis I at SB sites were Brachionus angularis, Pompholyx complanata, Keratella valga, Keratella quadrata, Filinia terminalis (rotifers), and Eubosmina coregoni and Daphnia (cladocerans). These species had axis scores which were significantly correlated (p<0.01) with bacterial density and bacterial phosphorus, total phosphorus, and algal density. Very high baterial density and very abundant bacterivorous rotifers in SB suggest that the transport of bacterial carbon through rotifers may be a relatively important link to higher trophic leaels. We believe that this "microbial carbon flow" from the base of the food web may be important in determining the suitability of SB as a spawning site and nursery for larval and juvenile fish.nile fish.

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Vegetation Types and Soil Environment as Affected by Fallow Paddy (휴경논이 식생유형 및 토양환경에 미치는 영향)

  • Oh, Young-Ju;Lee, Byung-Mo;Sohn, Soo-In;Lee, Yong-Ki;Nam, Hong-Sik;Lee, Sang-Beom;Kang, Chung-Kil;Jee, Hyeong-Jin
    • Korean Journal of Weed Science
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    • v.30 no.4
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    • pp.405-411
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    • 2010
  • The phytosociological study was carried out to investigate the structural characteristics of fallow paddy vegetation in Korea. The vegetation data of total 22 relev$\'{e}$s were analyzed by the Zurich-Montpellier school's method. Six syntaxa (1 subassociations and 5 communities) of fallow paddy were recognized: Polygonetosum thunbergii typicum subass. nov. hoc., Aneilema keisak community, Juncus effusus var. decipiens community, Phragmites commuis community, Monochoria vaginalis var. plantaginea community, Typha orientalis community of Polygonetum thunbergii Lohm. et Miyawaki 1962. Detrended correspondence analysis showed that Aneilema keisak community and Monochoria vaginalis var. plantaginea community were negatively correlated with soil total nitrogen. Polygonetosum thunbergii typicum subass. nov. hoc. and Phragmites commuis community was distributed in the soil with low pH.