• The Korean Journal of Ecology
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• v.24 no.5
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• pp.273-280
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• 2001

We investigated the flora and vegetation structure of exotic plants along stream geomorphology and disturbance factors in the riparian zone of Seunggi stream, Incheon. Total 53 exotic plant species were found in the riparian corridors of Seunggi stream. The percentage of exotics ranged from 25% to 33% of total species richness, and its mean value was 24% in the whole riparian area. The percentage of exotics reflected the vulnerability of riparian zones to plant invasions by disturbances, and it could be used as an indicator of riparian system dysfunction. The distinct distribution patterns of exotic plants did not found in the lateral topographic features of the stream. Invasion and proliferation of the exotic plants were somewhat remarkable at terraces and bank slopes of the stream. Among various disturbance factors, plowing and trampling were important on the invasion of exotic plant species of Seunggi stream.

• Journal of Species Research
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• v.2 no.1
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• pp.55-68
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• 2013

Previous surveys on Ulleung-do (Dagelet Isl.) found just ten earthworm taxa while the current survey unearthed a dozen species. Placement of parthenogenetic 'tube' Amynthas dageletensis Hong & Kim, 2005 is resolved as it clearly belongs in synonymy of Metaphire soulensis (Kobayashi, 1938) which becomes a new Ulleung-do record. Other new megascolecids are recorded since Amynthas heteropodus (Goto & Hatai, 1898) and A. baemsagolensis Hong & James, 2001 are confirmed as synonyms of A. corticis (Kinberg, 1867) and A. carnosus (Goto & Hatai, 1899), respectively. The latter taxon is differentiated and its synonym A. pingi (Stephenson, 1925) provisionally revived. New lumbricids are Bimastos parvus (Eisen, 1874), Eisenia japonica (Michaelsen, 1892) and questionably Dendrodrilus rubidus (Savigny, 1826). All confirmed species are common exotics with no endemics. Drawida moniligastrids were not yet located on this remote island for reasons unknown.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.225-232
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• 2008

To find out the status and characteristics of exotic plants in the Gwangreung Forest, a representative forest ecosystem in central Korea, we surveyed the species composition, coverage, and habitat illuminance of exotic plant species in a set of quadrats established along roads and trails in and around the Gwangreung Forest and buffer zone areas, In 1932, only five species of exotic plants were found along paths and roads in the Gwangreung Forest. However, the number of species in the forest has dramatically increased since 2000, when Ambrosia artemisiifolia L. and A. trifida L. were first recorded, and in 2007, 38 species of exotic plants were recorded. Among the 11 families, 23 genera and 25 species of exotic plants recorded in the quadrats, Compositae was the most common family (11 species), and perennial herbs, 42%, were the most frequently occurring life type, followed by annual herbs (31%) and biennial herbs (19%). Plants of North American origin comprised 48% of exotic species identified in our surveys. Exotics were found most frequently in quadrats along roads in the forest, followed by the buffer zones and hiking trails. The number of species and individuals of exotic plants decreased as we moved deeper into the forest, but Aster pilosus Willd. and Erigeron annuus (L.) Pers. were identified along hiking trails in the interior, and appeared to be capable of spreading further and more rapidly into the forest than other species.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.546-552
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• 2007

The objectives of this study were to analyze fish compositions, based on trophic guilds and tolerance guilds and determine community characteristics structure at five sampling sites of Yeongsan Lake during July 2006-May 2007. Total number of species sampled was 30 species and the number was 1350. Cyprinidae (77%) and Centrarchidae (15.7%) dominated the community and then followed by Cobitidae(2.7%), Gobiidae(2.4%), Mugilidae (0.5%), and others (0.1%). The relative abundance of tolerant and omnivore species at all sites was 63% and 77% of the total, respectively, suggesting an ecological degradations in the Lake. Exotics species such as large mouth bass (Micropterus salmoides), which is a top-carnivore in the water distributed at all sampling sites, implying that ecological disturbance was severe based on previous reference of US EPA (1991). Also, we found external anomalies such as external deformities, bleeding and tumors and not found migratory fish. Analysis of fish community structure showed that species diversity index and richness index was the highest in Site 1 and the dominance index was the highest in Site 2. In this study, high proportions of tolerant species and omnivore species, widespread exotic species, and frequent observations of abnormal fish. Such problems may be directly or indirectly associated with high nutrient enrichments and the reduced flow velocity by the dam construction. The ecosystem restoration by dam removal or removal of exotic top-carnivore fish may be one of the best strategies for better lak management.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.87-92
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• 2007

Twenty - four elite mulberry germplasm each of indigenous and exotics were studied for their leaf yield and compared with commercial check ($V_1$ and Kosen). Accession MI-0416 and ME-0169 out yielded the check accession in leaf yield/plant. The other few mulberry germplasm were also performed at par with the checks. For quality test and bioassay were conducted with the leaves of selected mulberry germplasm. Among the selected twelve mulberry accessions used for bioassay, MI-0376 and ME-033 performed better than check ($V_1$, Kosen). Other mulberry accessions i.e., MI-0310 and MI-0437 are on par with the check as far as the bioassay is concerned. MI-0376 and ME-0033 out yielded in rearing parameters and qualified for 11 and 10 rearing and related traits. Other mulberry accessions i.e., MI-0310 and MI-0437 were also qualified for eight rearing traits along with check ($V_1$). The mulberry accessions tested after selection from the preliminary characterization seems to be better and equally good in rearing and leaf yield compared to check ($V_1$, Kosen), which provides scope for selection and further evaluation. The selected mulberry accession may be included in crop improvement programme.

• Journal of Forest and Environmental Science
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• v.26 no.3
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• pp.161-170
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• 2010

A study was conducted for indentifying the floral biodiversity of woody species by calculating four diversity indices using data collected from 4 stands of different age groups and disturbance regimes in two areas of Madhupur tract. Results showed that highest species diversity in the old growth secondary coppice forest (>60 years) under moderate anthropogenic disturbances of Madhupur National Park area (delete (D=0.74, H'=3.36) followed by old growth secondary forest stands (>40 years) under moderate disturbances at Bhawal National Park area (D=0.65, H'=2.81). Plant species diversity of the young enrichment plantations (<20 years and <15 years) under high anthropogenic disturbances in both the areas are much low (D=0.54 and H'=2.16 and D=0.52 and H'=1.92 respectively), which indicate high anthropogenic disturbances coupled with introduction of invasive exotics that are rival for endemic species are detrimental for conservation of biological diversity of tropical moist deciduous forests of Madhupur tract in Bangladesh.

• Journal of Environmental Science International
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• v.16 no.5
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• pp.549-559
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• 2007

Vegetation surveys were performed at 45 plots along 10 highways cut slopes in South Korea. Total floral inventory, species richness and exotic plant percentage were obtained within each plot. Life history and life form of each species appeared were analyzed. Community types were classified using hierarchical cluster analysis and detrended correspondence analysis and non-metric multidimensional scaling were conducted from vegetation matrix. 292 species of vascular plants were discovered and the number of natives and exotics were 226 and 66, respectively. There were no significant differences of species richness and exotic plant percentage between cut slopes and rest areas. Hierarchical cluster analysis indicated five clear vegetation associations in cut slopes and rest areas. Detrended correspondence analysis indicated that species composition of total and native plants were similar along the highway cut slopes whereas exotic plants were distributed differentially along the highway cut slopes. in non-metric multidimensional scaling, the studied sites were more separated from each other on the basis of their species composition than the results of detrended correspondence analysis with respect to total, native and exotic plants. The both ordination represented that exotic plants have not been made uniform yet on cut slopes and rest areas by highway corridor in spite of diverse chronosequences after highway construction termination (1 to 22 years). This study showed that the distribution of species composition in exotic plants was different and localized on cut slopes and rest areas of highway in this representative peninsula area of North East Asia and the invasion of exotic plants can retard the process of plant species homogenization.

• Journal of Forest and Environmental Science
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• v.32 no.2
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• pp.129-139
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• 2016

Study was conducted to investigate tree diversity and its population and regeneration status in homegardens of upper Assam, Northeast India through field study by quadrat method. A total of 154 tree species have been recorded from 135 studied homegardens under 109 genera 53 families. Most of these species (79%) are indigenous to our country, while the rest (21%) arealiens (naturalized and cultivated exotics) by origin. Tree species richness per homegarden varies greatly in different homegardens and is ranged from 5 to 52 tree species with a mean of 22 ($SE{\pm}0.58$). A. malaccensis is the most dominant tree species in the studied homegardens contributed 34% of the total tree density of the documented trees. The tree density is much higher with 4,259 individuals $ha^{-1}$ but, basal area ($36.32m^2ha^{-1}$) is very less. Based on the number of individuals present, very rare species is accounted for 10%, rare species 39%, common species 19%, dominants 14% and predominant species 18% in the present study. The population density of 154 tree species is 4,259 (individuals $ha^{-1}$) for adults (>3.18 cm DBH), 5,902 (individuals $ha^{-1}$) for saplings and 38,164 (individuals $ha^{-1}$) for seedlings. The density of seedlings>saplings>adults represents good regeneration status of tree species in studied homegardens. The population structure study showed that about 8% tree species have good regeneration status, 9% have fair regeneration status, 48% have poor regeneration status and 34% tree species have no regeneration. Study suggests that research and development action is needed to stimulate regeneration of those tree species which having high importance value indices but showing poor or no regeneration. Based on present observation, it can be conclude that homegarden can emerge as an effective means for both economic well-being and biodiversity conservation in upper Assam, Northeast India.

• Journal of Species Research
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• v.1 no.2
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• pp.105-132
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• 2012

The saga of Megascolides orthostichon (Schmarda, 1861)-the first native worm described from Australasia-continues as its type-locality is unequivocally returned from Hobart, Tasmania to Mt Wellington, Auckland where a brief survey failed to unearth it. Since it has not been seen for 150 yrs, it may qualify under NZTCS or IUCN classification as 'Nationally Critical' if not 'Extinct'. New reports are for exotic Megascolecidae Anisochaeta kiwi sp. nov. and A. kiwi mihi sub-sp. nov. plus addition to the NZ faunal list of Australian Anisochaeta macleayi (Fletcher, 1889) that, due to its wide distribution in Australia and now New Zealand, may be a candidate model-species suitably resilient for eco-toxicological culture and monitoring. For holarctic Lumbricidae, new records are of Dendrobaena attemsi (Michaelsen, 1903) and the Murchieona muldali (Omodeo, 1956) morph or subspecies of M. minuscula (Rosa, 1906), neither lumbricid previously uncovered in Asia/Australasia. Also found for the first time outside its East Asian homeland is Eisenia japonica (Michaelsen, 1892) (which is compared to Japanese E. japonica hiramoto sub-sp. nov. and to E. anzac Blakemore, 2011). Records of these exotics plus recent new native species described by the author-including two, Rhododrilus mangamingi and Deinodrilus orcus spp. novae, herein-raise the numbers of megadriles known from New Zealand to 228 (sub-)species in five families. Preliminary mtDNA COI sequence barcodes are presented. Genus Tokea Benham, 1904 is revived on its lack of dorsal pores, losing or gaining some species with Megascolides M'Coy, 1878. An updated checklist of all 228 New Zealand taxa is appended.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.65-70
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• 2016

Investigation on weed flora in Angelica gigas upland fields was conducted to understand the current status of the weed flora and establish the control measures. Investigation was conducted twice, July and October in 2015. From this investigation, 105 species of 37 families including 27 exotics were identified and classified into 53 species of annuals, 24 species of biennials and 28 species of perennials. Dominance was the highest with Digitaria ciliaris, followed by Portulaca loeracea, Chenopodium album, Cyperus iria, Conyza canadensis, Galinsoga ciliata etc. in order. Chenopodium album was the highest in importance analysis and the followings were in order of Conyza canadensis, Galinsoga ciliata, Amaranthus lividus, Taraxacum offcinale etc. The yield of A. gigas was reduced 49.6% in no weeding plots comparing in weed managed plots.