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- KOREAN
- P-ISSN2287-8327
- E-ISSN2288-1220
- SCOPUS, KCI
ISSN : 2287-8327
Vol.28 No.3
Abstract
To reveal vegetation history and environmental changes in Mt. Jiri, sediment cores were collectedfrom Wangdeungjae moor of Mt. Jiri. Overall dry matter accumulation rates and sedimentation rates by 14C-dating were 0.027 kgㆍm-2ㆍyr-1and 0.184 mm/yr since 1250 (76040 yrs BP, 14 cm in depth). There are three pollen zones; the first zone is below 14 cm depth where Quercus dominated, the second zone is from 14 cm to 6 cm depth where Gramineae increased and Quercus and Salix dominated and the third zone is from 6 cm depth to the top where Pinus and dominated. Total pollen concentration gradually increased from bottom to the top of sediment core, which implies wet, anaerobic and cool condition during covered period by the core. Calcium and magnesium contents had increased since 14 cm depth, with peaks at 13 and 20 cm depths. This indicates that groundwater had recently become relatively more important than surface water as water source of Wangdeungjae moor. Exotic plant or Chenopodiacea pollen was less than 1%. There was little variation in total N and P contents along the length of the core. These results support that Wangdeungjae mor has been little affected by anthropogenic activities. Also, nutrients and heavy metal contents indicate the baseline condition of Wangdeungjae moor.
Abstract
The monthly variations of physico-chemical and microbiological water quality were investigate in the artificial Lake Geumgang near estuary barrage. Sixty heterotrophic bacteria were isolated and identified by amplification and sequencing of 16S rDNA. Water temperature, pH, and inorganic nutrients(NH4-N, NO2-N, NO3-N, PO4-P) were measured. Concentrations of DO, BOD, and inorganic nutrients were lower than in the middle-stream of Geum river. The population densities of heterotrophic bacteria and total coliforms varied from 4.1 ± 1.0 × 102 to 6.7 ± 1.1 × 103 cfu ml-1, and 0 to 2.3 ± 0.6 × 102 cfu ml-1, respectively. Among the measured numbers of physiological groups of bacteria, cellulolytic bacteria showed higher population densities than those of other physiological groups. Bacterial community structure was analysed based on 16S rDNA partial sequencing. Among 60 isolates, dominant genus was seudomonas (20 strains).
Abstract
This study was carried out to find the allelopathic effect of volatile materials released fromEupatorium rugosum. The GC method was employed for analysis of volatile materials from E. rugosum and 49 chemical substances were identified such as β-caryophyllene, α-terpinenol, chamazulene, bornyl acetate, α-pinene, etc. including unidentified thre chemicals. Germination test in Phaseolus radiatus was done to find the inhibition effect of volatile materials using some chemicals which were proved to be important component or much amounts ones in E. rugosum. It was strongly inhibited by linalool and terpinen-4-ol. Seedling elongation and radicle growth of that were proportionally inhibited by the concentration of the essential oil, especially α-pinene and bornyl acetate. Biomass of receptor plant was slightly decreased more than 58 μl of the extract in case of α-pinene, while it was decreased more than 19 μnon-significant. From the above results, it was found that volatile materials from E. rugosum showed a allelopathic effect and also α-pinene, bornyl acetate, linalool and terpinen-4-ol used in bioassay were some of major allelochemicals in germination inhibition and especially linalool and terpinen-4-ol are prominent effect on growth inhibition of other plant.
Abstract
To clarify seed distribution in sediment and its burial properties of Suaeda japonica, the vertical and horizontal distribution of seeds, organic content of sediment, and sediment content delivered by crabs were studied in mud tidal-flat of Walgot-dong, Siheung, Gyeonggi Province, from March 1999 to October 2000. The 94% and 6% of S. japonica seeds were buried under and outside the maternal plant crown, respectively. Organic matter contents of sediment were higher at the area (17%) covered than at the one (8%) uncovered by S. japonica. In the area covered by S. suaeda, organic matter profiles of sediment showed vertical variation from 19% in surface (1 cm depth) to 14% in 6 cm depth. S. japonica seeds buried in sediment decreased from 45% in 2 mm depth to 0% in 12 mm depth. The density of crabs was higher in the vegetated area than in the non-vegetated one. Especially, the density of Cleistostoma was about 8 times higher in the former than in the latter. In the vegetated area, the amount of sediment delivered by crabs was estimated to be 2,409 cm3․m-2, and this could ascend the height of sediment to 2.4 mm. Consequently, it might be interpreted that plant debris (organic matters) of maternal plants and sediment delivered by crabs made the S. japonica seeds bury well. By relationship between crab distribution and vegetation, it was thought that crabs got a benefit from S. japonica.
Abstract
This study was conducted to elucidate the relationship between the aboveground vegetation structure and fine roots of the topsoil (<15 cm), and thereafter to obtain the regression models for the estimation of the fine roots of the topsoil using the aboveground vegetation values in the burned forest areas, Korea. The FRT (fine roots of the top soil) as well as the aboveground vegetation structure showed spatial variation in the earlier successional stages after forest fire. The fine roots (<2 mm) of the topsoil in the earlier successional stages than the first 3 year after forest fire showed the range from 3 to 166 g DM/m2. The FRT in the naturally regenerated sites and planted sites after forest fire was closely correlated with the vegetation indices, especially Ivc, representing the development status of the aboveground vegetation. The FRT in the terrace seeding work sites after forest fire was closely correlated with year elapsed after terrace seeding work. The FRT in the terrace seeding work sites showed the much higher values because of the vigorous growth of grass species than the other sites. In the naturally regenerated sites, the FRT showed the parabola form according to the increment of aboveground vegetation value (Ivc). Although the aboveground vegetation value (Ivc) showed a tendency to increase logarithmically during the secondary succession after forest fire, the estimated fine roots of the topsoil was depicted the parabola form showing the gradual increment until the first 15 years and slight decrease thereafter. Decrease of FRT in the later successional stage showing the high vegetation value may be caused by increment of the woody species contribution to the vegetation value (Ivc). Our results represented that the boveground vegetation value (Ivc) can be used to the estimation of the fine roots of the topsoil in burned forest areas
Abstract
In order to investigate the geographical variation of Glycine soja distributed in southern area of Korean peninsula, 8 local populations(Sokcho, Wonju, Mt. Chiak, Cheongju, Andong, Taegu, Ulsan, Sacheon), which located from 34˚50´00"N to 38˚12´00"N, were selected according to their latitudes and geographical distances. The seeds of these populations were collected and their contents of mannose and galactose were investigated. Mannose contents in the seeds were variable in the range between the highest 460.00 mg/g (Andong) and the lowest 55.23 mg/g(Sacheon). The contents of galactose were represented remarkable differences from 67.17 mg/g(Sacheon) to 387.50 mg/g(Ulsan) also. The local populations were classified into 3 types such as the middle southern inland type (Andong, Taegu), the middle northern type(Wonju, Mt. Chiak, Cheongju) and the coastal type(Sokcho, Ulsan, Sacheon) according to the ratio of mannose and galactose, which indicate the hardness of seeds in Leguminosae, ranged from 0.41 to 1.73. Particularly, those of middle southern inland populations represented the high values compared with those of other populations.
Abstract
This study was carried out to estimate above-ground biomass and inorganic nutrient distribution for a Camellia japonica stand located Mt. Cheon-gwan, Jeonnam province. Regression analysis of biomass for stem, current twig, branch and foliage versus diameter at breast height(DBH) was used to calculate regression equations of the form of logY = a + blogD(Y: component biomass, D: DBH). Total above-ground biomass for a Camellia japonica stand was 115.2 ton/ha(47.9 for main stem, 1.4 for current twig, 53.4 for live and dead branch, 5.6 for current foliage and 6.9 for ≥1-yr-old foliage). Component biomass was non-linearly correlated with DBH, and the difference in biomass between ≥1-yr-old and current foliage increased in proportion to DBH. Current foliage and live branch showed higher N, P and K concentrations compared to ≥1-yr-old foliage and dead branch, respectively. However, Ca concentration of current foliage and live branch was lower than that of ≥1-yr-old foliage and dead branch, respectively. Total above-ground inorganic nutrient contents(kg/ha) were distributed as follows; K: 366.4, N: 442.7, Ca: 433.3, Mg: 118.4, P: 50.5 and Na: 25.3. The proportions of inorganic nutrient content for live branch were generally the highest in all the inorganic nutrients.
Abstract
Nitrogen dioxide concentration was being grown ca. 8% per year although sulphur dioxide con-centration was being reduced ca. 10% per year in Seoul from 1996 to 2003. The rainwater was heavily acidic with pH 4.19 to 4.68 in Seoul during 1980 to 1991. Acidity score on the basis of the total anion concentration of rainwater follows the higher in sequence with Seoul(Kwanaksan)(341.5 μequivL-1), Gwangneung(199.2 μequivL-1) and whole Korea mean(101.3 μequivL-1). Rainwaters from 38 sampling sites of 16 countries in the world, on the basis of the acidity score, are classified and designated as five acid rain grades(ARG): the least score is founded in Tana Rata(16.2 μequivL-1), Malaysia where has the best rain but the greatest founded in Chongquing(541.1 μequivL-1), China where has the worst rain in the world. Even though acidic deposition decrease with time in the world generally, it is expected to increase in Asia, Africa and Mid-South America.