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- KOREAN
- P-ISSN2287-8327
- E-ISSN2288-1220
- SCOPUS, KCI
ISSN : 2287-8327
Browse Articles
e-SubmissionVol.29 No.5
Abstract
The mating systems of two groups of natural populations of Gleditsia japonica var. koraiensis inKorea were determined using allozyme analysis. The result suggests that G. japonica var. koraiensis is pre-dominantly outcrossing. The tm values of eight populations in Korea varied from 0.667 (Mdh-1) to 0.938 (Idh-1), giving an average 0.820. Population and individual outcrossing estimates were associated with flowering tree density or degree of spatial isolation. The reason for relatively low outcrossing rates of some populations could be atributed to reduction of efective population sizes of sib for the medicine, small population size, and isolation of flowering mature tres. The heterozygote exceses were observed in some natural populations, whereas other populations exhibited varying degrees of inbreeding a nd heterozygotes deficit. Thus, selection against homo-zygotes operated in the progeny populations throughout the life cycle.
Abstract
The tadpoles of 12 Korean anuran species, including Bombina orientalis, Bufo gargarizans, B.chosenica, R. rugosa, and R. catesbeiana, were classified based on their morphological characteristics. We collected eggs or tadpoles of the 12 Korean anuran species from Gangwon, Incheon, Chungcheong, and Gyeong-gi districts in 2005 and 2006 breeding seasons. When the tadpoles reached at 27∼37 Gosner's developmental stages, we described morphological characteristics of the tadpoles of each anuran species and measured their physical parameters such as total length, body length, and body mass. After that, we chose 12 morphological characteristics to identify each species and to use them as classification keys such as eye location, caudal musculature pattern, spiracle location, oral disc morphology, and labial tooth row formula. In this paper, we cs, and drawings for the tadpoles of 12 anuran species.
Abstract
To elucidate the mechanisms by which algal food quality affect Daphnia growths, we measuredcarbon incorporation rates and respiration rates of Daphnia magna with Cryptomonad Rhodomonas minuta , green algae Scenedesmus acutus and cyanobacteria Synechococcus sp. with varying physiological states as R. minuta and S. acutus and low with Synechococus sp. showing a similar pattern to the growth rate pattern. There was no clear difference among respiration rates of three algal species. Carbon assimilation rates and respiration rates of D. magna appeared to be independent on Molar C:P ratios in algal foods. Carbon growth efficiencies (incorporated carbon per assimilated carbon amount) were lower when D. magna fed with Synechococcus sp. than fed with R. minuta or S. acutus. Analysis of variance results show that carbon assimilation rates which were sum of incorporation and respiration rates and carbon growth efficiencies were only dependant on s showed that algal species with varying ω3 polyunsaturated fatty acid content led different carbon incorporation rates and overall carbon assimilation rates of D. magna.
Abstract
Soil properties of Quercus variabilis forest on Youngha valley at Mt. Worak National Park werestudied as a part of Korea National Long-Term Ecological Research. Soil sampling was carried out along the 50 cm soil depth with 10cm intervals at every quarter from May 2005 through July 2006. Fresh soil was used for NH4+-N, NO3--N, and soil water content determination. Remaining soils were air dried in the shade, and then used for determination of soil pH, T-N, T-P and exchangeable cation. Average soil organic matter in top soil 3and increased with soil depth. Soil organic matter and bulk density showed a negative linear correlation (R2=0.8464). Soil pH in top soil and subsoil was similar. T-N, NH4+-N, NO3--N and T-P in top soil were 1.9 0.5 mg/g, 7.3 1.0 mg/kg, 2.0 0.4 mg/kg and 0.2 0.05 mg/g, respectively. K+, Ca2+and Mg2+in top soil were 84.6 24.4, 408.8 137.8 and 93.4 23.0 mg/kg, respectively. They decreased with soil depth. Amounts of organic matter, T-N, NH4+-N, NO3--N, T-P, K+, Ca2+and Mg2+in 50 cm soil depth were 250.9, 3.45, 0.025, 0.003, 0.639, 0.181, 0.845 and 0.302 ton ha-150 cm-depth-1, respectively.
Abstract
Upo wetland is the largest inland wetland in Korea as Ramsar Convention Area. The purposesof the study were to investigate the levels of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the sediment and Cipangopaludina chinensis malleata from three sites of the wetland and to assess the potential of the gastropod as a bioindicator for heavy metal levels. The gastropods were dissected into shell and soft tissue without the digestive and excretive organs. The levels of Cd, Cu and Pb were below the guideline of Soil Environment site (0.32 μg/g) than Sajipo site (0.28 μg/g). Cu and Zn showed the highest value in Sajipo as 43.5 μg/g and 39.8 μg/g, respectively while the concentrations of Pb and Zn were the highest in Upstream as 58.8 μg/g and 138 μg/g, respectively. In the soft tissues and shells of the gastropod, the overall comon trend in the concentrations of the heavy metals was revealed with the following order: Zn > Cu > Cr > Ni > Pb > Cd and Ni > Zn > Cr > Cu > Pb > Cd, respectively. Although the soft tissues exhibited higher concentrations of the heavy metals except Ni than the shell in the gastropod, the levels of Cd and Pb in the gastropod were generally below the restrictive values set up by Korea Fod & Drug Administration. From Duncan's Multiple Range Test (DMRT) results, the concentrations of Pb and Zn in the sediments among the sites were reflected on the soft tissue (Pb) and the shell (Pb and Zn) of the gastropod in the same order. The lower value of coefficient of variation (CV) in Pb concentration of the shell than in that of the soft tissue supports the usefulness of the shell as a bioindicator for Pb pollution. Although the CV value in the shell was a little higher than in the soft tissue, DMRT results and the stability of incorporated Zn into the shell support the use of the shell of the gastropod
Abstract
The growth patern and the seasonal changes in nutrient contents of Humulus japonicus wereinvestigated. Stem length of H. japonicus reached the maximum from 240 to 260 Julian date and the median value was found at 255 Julian date. The maximum leaf area was observed from 235 to 248 Julian date and the median value was at 240 Julian date. The maximum growth rate of the stem length ranged from 205 to date in the growth rate of the stem length and leaf area was 212 and 205 Julian date, respectively. The growth rate of H. japonicus was related to rainy season and precipitation. Phosphorus and sodium contents of H. japonicus were correlated with maximum potential rate of relative growth. Although stem biomas of H. japo-nicus was 1.5∼3.5 times larger than that of leaf, N content of the leaf (4.48∼5.27%) was about 2 times higher than that of the stem (2.0∼ H. japonicus in sumer. This result provides valuable information for apropriate timing for the removal of H. japonicus.
Abstract
The composition changes of litters were investigated to figure out the effects of the decompositionof Humulus japonicus on nutrient circulation and decomposition process in the riverine wetlands: Tan stream and Amsa-dong. Litterbags (mesh size 1 mm and 5 mm) were installed to monitor mass and nutrient changes of 5 types of litters: H. japonicus only, Miscanthus sacchariflorus only, Phragmites communis only, mixed litters including H. japonicus, and mixed litters without H. japonicus for 7 months. It was shown that k (decay rate) of the H. japonicus (2.68∼3.12) was higher than that of (1.83∼2.16) and P. communis (0.02∼1.18). The mass and organic remaings of the mixed litters including H. japonicus at Tan stream were 47.0∼55.1% and 47.0 ∼54.9% and those of the litterbags without H. japonicus were 49.2∼65.4 % and 47.1 ∼57.5%, respectively. This result indicated that the nutrient circulation was faster at H. japonicus community than others. Ca, Na, Mg, K, P, C, N and H contents reduced to around 40∼80% of original. However, Na concentration increased up to 407 ∼584% at 100 days and decreased to 248 ∼498% at the end of the experiment. Decomposition rates were similar between 1mm and 5mm mesh size litterbags and this implies that plant litters in studied areas decomposed mainly by microbes rather than small animals. This study revealed that the fast growth of H. japonicus was resulted from fast decomposition in part: positive feedback of nutrient cycling.
Abstract
Ecophysiological parameters of non-transgenic sweetpotato (NT) and transgenic sweetpotato (SSA)plants were compared to evaluate their resistance to multiple environmental stresses. Stomatal conductance and transpiration rate in NT plants decreased markedly from Day 6 after water was withheld, whereas those values in SSA plants showed relatively higher level during this period. Osmotic potential in SSA plants was reduced more negatively as leaf water potential decreased from Day 8 after dehydration treatment, while such reduction was not shown in NT plants under water stresed condition. SSA plants showed les membrane damage than photochemical efficiency of PS II (Fv/Fm) in NT plants markedly decreased, while that in SSA plants was maintained relatively higher level. This trend of changes in Fv/Fm between SSA plants and NT plants was more conspicuous as simultaneously treated with water stress, high light and high temperature stress. These results indicate that SSA plants are more resistive than NT plants to multiple environmental streses and the enhanced resistive characteristics in SSA plants are based on osmotic adjustment under water stres condition and tolerance of membrane.
Abstract
Alometric equations for biomass measurement of the shrub species, Lindera obtusiloba, weredeveloped. The alometric equations between (BD)2H and dry weight of leaves (Wl), stems and branches (Wsb), rots (Wr) and total weight (Wt) of the Lindera obtusiloba were as follows: Wl=0.7318 (BD2H)0.6108, Wsb=0.6067 (BD2H)0.8355, Wr=0.4524 (BD2H)0.7608, Wt=1.672 (BD2H)0.7664. The R2s between (BD)2H and Wl, Wsb, Wr and Wt of the Lindera obtusiloba were 0.9251, 0.9571, 0.9353 and 0.9546, respectively. Root weight of this Lindera obtusiloba was about 38% of the aboveground biomass.