29권 4호
초록
Abstract
We investigated the impact of watermelon grafted onto Cucumber Gren Mottle Mosaic Virus(CGMMV)-resistant transgenic watermelon rotstock on insects as non-target organisms in a greenhouse in2005. We quantitatively collected insect assemblages living on leaves and flowers, and we used sticky traps to(Aphis gossypii Glover) on watermelon leaves and western flower thrip (Frankliniella occidentalisTrybom) onwatermelon male flowers, betwen CGMMV-resistant transgenic watermelon (TR) and non-transgenic water-melon (nTR). Non-parametric multidimensional scaling (NMS) ordination verified that insect assemblages onleaves and sticky traps were different between TR and nTR (P < 0.05). The insect assemblages on male flowerswere not statistically significant. Multi-response permutation procedures proofed our esults from NMS results (P> on leaves and sticky traps, but watermelon male flowers do not show an adverse effect. Further research isrequired to assess the ffect of TR on the aphid and western flower thrip. Life table experiments might supportthe specific reason for the adverse effects from leaf assemblages. Assessment of non-target impacts is anessential part of the risk assessment of non-target insects for the impact of transgenic organisms.
초록
Abstract
We investigated the distribution of three anuran species, Three-striped pond frogs (Rananigromaculata), Bullfrogs (Rana catesbeiana ), and Narow-mouthed toads (Kaloula borealis), in an administrativeveyors were assigned to each 2 2 km2survey plot. Call surveys on whether the species are present or notwere conducted for 5 minutes between 30 minutes after sunset and the midnight on rice fields and ponds from10 April to 28 August in 2005. Depending on species, call surveys were carried out at seven to 28 plots withaverage 8.4 to 10.7 visits per the plot. We calculated the detection probabilities and occupancy rates of the threespecies using four models with three covariates: temperature, humidity, and the amount of water at the habitat.The model average detection probabilities of thre anuran species of R. nigromaculata, R. catesbeiana,and K.borealis were 0.53, 0.74, and 0.41 respectively, and the site occupancy rates of them were 0.93, 0.94, and 0.86respectively. Our results indicate thatR. nigromaculata, R. catesbeiana,and K. borealisare common in HaenamGun.
초록
Abstract
The total monoterpenoid content of the pine litter layer and the availability of these compoundsas inhibitors/stimulators onPolysphondylium violaceum of cellular slime molds were investigated. In order tosenescent, and decaying needles from 3 pine species ( Pinus densiflora, P. thunbergi, P. rigida) by litter bagmethod. Total monoterpenoid content was highest in the fresh needles, but also remained relatively high insenescent needles. The effect of monoterpenoids identified fromPinus plants on the growth ofP. violaceum wasstudied. We tested four concentrations (1, 0.1, 0.01, and 0.001μg/μL) of each compound by using a diskvolatilization technique. Each compound was treated after germination of spores ofP. violaceumcompounds at 1 μg/μL concentration had a very strong inhibitory effect on cell growth ofP. violaceum.Fenchone at all concentrations, myrcene, verbenone, bornyl acetate, and limonene at low concentrationsstimulated the growth ofP. violaceum. These results suggest that inhibitory or enhancing effects of selectedmonoterpenoids depend upon the concentration of the individual compound.
초록
Abstract
This study investigated the relationship between land cover and the water quality variables in therivers, which are located in the Yamaguchi prefecture of West Japan. The study area included 12 catchmentscovering 5,809 Km2. pH, dissolved oxygen, suspended solid, E. coli, total nitrogen and total phosphorus wereconsidered as river water quality variables. Satellite data was applied to generate land cover map. For linkingalterations in land cover (at whole catchment and buffer zone levels) and the river water quality variables,(at whole catchment level) consistently explained high amounts of variation in biological oxygen demand (72%),suspended solid (72%) and total nitrogen (87%). At buffer zone-scale, multiple regression models that weredeveloped to represent the linkage between the alterations of land cover and the river water quality variablescould also explain high level of total variations in suspended solid (86%) and total nitrogen (91%).
초록
Abstract
Ecological correlates of lowering times often are examined to infer evolutionary mechanisms forpollination modes with flowering times among 3,037 Korean angiosperms experiencing strong climaticseasonalities. We first examined taxonomic membership effects on flowering times across diverse taxonomiclevels. Phylogeny constrained flowering times at all levels down to the genus level. We then analyzed the fectsof ecological characteristics using subset data consisting of species randomly selected from each genus tocontrol phylogenetic effects. The commonly observed patterns of early flowering of woody species in temperateregions existed. Spring flowering shrubs and trees, however, both being wody, were involved with biotic andgrowing season than perennials although both herbs tended to be associated with abiotic vectors when floweringin autumn. These results support our hypothesis that species able to decouple vegetative and reproductivegrowth flower in springs dry season, but species with different habits, even when they flower within the sameseason, are subjected to different selective pressures for efficient pollination.
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Abstract
The objective of the current study was to characterize and apply multiple regression model relatingto vegetation values of the plant species over salt marshes. For each salt marsh community, vegetation andsoil variables were investigated in the western coast and the southern coast in South Korea. Osmotic potentialof soil and Cl-content of soil as independent variable had positive and negative influences on vegetation values.Multiple regression model showed that vegetation values of 14 coastal plant communities were determined bypH of soil, osmotic potential of soil and sand content. The multiple regression equation may be applied to theexplanation of distribution and abundance of plant communities with exiting ordination plots.
초록
Abstract
Collection of moths in four Gotjawal terrains of Jeju Island was conducted using black light trap,beginning July through September 2005. The insects investigated were classified into 146 species, 15 familiesand 7 superfamilies, and Noctuoidea appeared to have acounted for 41.1%, or 60 species, which was thelargest number among them, followed by Geometroidea. was found to have been thedominant species over the entire area. The diversity index showed the highest at Aewol Gotjawal and the lowestat Hangyeong-Andeog Gotjawal. Aewol Gotjawal formed a cluster with Gujwa- Sungsan Gotjawal at he lowestchord distance (0.75). At the higher chord distance of 0.82, Jocheon- Hamdeog Gotjawal fused the cluster ofAewol Gotjawal and Gujwa-Sungsan Gotjawal. Hangyeong-Andeog Gotjawal fused with the rest three terrains,forming a single cluster at he highest chord istance of 0.89.
초록
Abstract
We analyzed the total yields and composition of essential oils in leaf extracts ofNepeta catariaby Gas Chromatography Mas Spectrometry (GC-MS). Thirty-six compounds representing 97.0% of total oil weredetected. The major constituents of essential oils inNepeta cataria were nepetalactone (90.9%), unidentifiedcompound (Retention time 17.35; 1.82%), 1,8-cineol (1.49%),β-caryophyllene (1.12%), and β-pinene (1.078%).The volatile compounds in leaf extracts ofN. catariaconcentrated to nepetalactone (88.83 93.33%) remarkably.～In the essential oil ofN. cataria cis,trans-nepetalactone (30.2 37.8%) and～ cis,cis-nepetalactone (31.5 37.0%)～were found as the main constituents. The effects of essential oil ofN. catariaon t h e g r o w t h o f s i x m i c r o -organisms (Bacillus cereus, B. subtilis, B. amyloliquefaciens, Escherichia coli, subsp.aureus, and Pseudomonas aeruginosa ) were investigated. The sential oil of N. catariahad strong inhibitoryeffect on the growth of three fungal species (Bacillus cereus,B. subtilis, and B. amyloliquefaciens). The essentialoil fromN. catariawas found to have a low antimicrobial activity againstStaphylococcus aureus subsp. aureus,while no activity were found againstEscherichia coli and Pseudomonas aeruginosa . Results indicate thesignificant antimicrobial effect, which may be depended on the yield of nepetalactone.
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Abstract
To examine sediment characteristics and find anthropogenic effects on riverine wetland eco-systems, paleoecological study was carried out at Bamislands in Seoul. Three hundred cm deep sediment coreswere retrieved and dated with the lamination analysis method until 36 cm depth (1986). Sediments were dividedinto three zones based on the depth profiles of physico-chemical variables: below 160 cm depth (before 1968),betwen 160 and 40 cm depths and above 40cm depth (after 1986). Physico-chemical characteristics were veryheavy metal concentrations were relatively low, Cd and As contents have increased continuously. Dry massaccumulation rates during 1968~1986 and 1987~2003 were 140 and 21 kg m-2yr-1, respectively. This wasrelated to flooding intensity and duration. Bulk density,water content, loss on ignition, N, C, C/N ratio were verysimilar to ther river delta but Ca, Na nd K contents were 2 to 4 times higher than others. Heavy metal contentsexcept Pb were lower or similar to those in other studied marshes in Korea. Heavy metal and Mg contents were13C d a t i n gdates of organic materials in sediment, it is uggested that organic matter originated from the watershed andflooding intensity in the watershed might be responsible for the source of sediments. This study providesreference data for the comparison of sediment characteristics at islands in river and for the management of Bamislands.
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Abstract
This study was carried out to investigate the population densities, R/S ratios, and identification ofheterotrophic bacteria on the rhizosphere soil of halophyteSuaeda japonica found on the western and southernmudflats of Korea. The population densities of aerobic and anaerobic heterotrophic bacteria on the rhizospheresoil of Suaeda japonica were in the range of 1.3 0.3 106~ 6.3 3.3 1074~ 1 . 8 0 . 7 107cfu g-1d. wt., respectively. In case of physiologicaly specific bacteria, population densities of amylolyticbacteria on the rhizosphere soil ofSuaeda japonica were in the range of 4.4 0.6 106~ 2.5 1.2 107cfu g-1d. wt., those of cellulolytic bacteria were from 8.5 6.0 104~ 2.3 1.6 106cfu g-1d. wt., and thoseof proteolytic bacteria were from 3.8 1.8 1056cfu g-1d. wt., respectively. The R/S ratioswere ranged from 2.33 to 2.39. Among eleven isolates from the rots of halophyteSuaeda japonica of Go-heung bay by using 16S rDNA analysis, five clones were closely related toγ-Proteobacteria group and sixclones were closely related toα-Proteobacteria group. Among four isolates from Suncheon bay, two strains wererelated toγ-Proteobacteria group and another two were related toActinobacteriaand Bacilli group, respectively.
초록
Abstract
Landscape changes for 20 years betwen 1981 and 2001 in the Wangsuk stream basin locatedon the central Korea were investigated on the basis of physiognomic vegetation map made from the aerialphotograph interpretation and field check. Changes of landscape structure were noticeable in agricultural fieldinto the institutional agriculture dominated landscape change, although urbanization also contributed to suchchange. The former change due to change of food production structure originated from socio-economicdevelopment during this period and the latter to the overpopulation of Seoul. As energy sources for heating andcooking, fertilizer, and fodder for livestock transform from plant materials to fossil fuel, manufactured one, andgrain, succession of forest escaped from direct human disturbance dominated change of landscape structure inforested land. Differently from the positive landscape change in the upper area, change in the lower areathe Wangsuk stream basin would influence water quality of the stream. In order to realize sustainable land-useagainst such environmental degradation, systematic environmental management based on landscape cologicalperspective such as an eco-plan for creating riparian vegetation belt, which is under preparation by Ministryof Environment, was recommended.