• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.145-152
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• 1992

Phosphorus(P) cycle of Miscanthus sinensis, Sasa palmata and Artemicia princeps for perennial plants and Polygonwn thunbergii for annual plant were investigated in natural plant communities established in Andosol region. 1. Perennial plants contained about 50-80 % P of the maximum accumulated in whole plant in under ground parts as reserve P before wintering. On the other hand, annual plant returned the most part of P in plant tissues to soil and wintered with a small amount of P in only seed. 2. The storage percentage of K was low compared to P in both perennial and annual plants. And the return of K from litter to soil proceeded rapidly because of easy leaching of K. 3. Perennial plants stored a large amount of P in reserve organs before wintering and carry it over next generation, and P holded in an individual showed a yearly increase. Consequently, P was less susceptible to depressive factor for growth of perennial plants even in poor P circumstances like Andosol region, compared to annual plant.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.495-504
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• 2001

The objectives of this study were to understand the characteristics of Cd and Pb accumulation in various tissues of poplar species and the effects of ectomycorrhizal inoculation on the accumulation of above two heavy metals in the tissues. The mycelial inoculum of ectomycorrizal fungus, Pisolithus tinctorius was produced in peatmoss and vermiculite mixtures, and inoculated into potted soil with fresh cuttings of four species of Populus, P. alba ${\times}$ glandulosa (Pag). P. koreana ${\times}$ nigra var. italica (Pkn), P. nigra ${\times}$ maximowiczii(Pnm), and P. euramericana(Pe). The potted soils were added with 0, 30, and 80 ppm Cd, and 0, 50, and 300 ppm Pb. The cuttings were grown outdoors for about five months until the plants were harvested for measurement of growth, mycorrhizal infection, and metal contents in leaves, stems, and roots. The total dry weight of Pe treated with Cd and Pb was increased by mycorrhizal inoculation, while that of three other species was not affected by the inoculation. Cd was accumulated in the highest concentration in Pag and its concentration was increased by four times by mycorrhizal inoculation. The Pag accumulated Cd in the highest concentration in the leaves, while three other species accumulated Cd most in the roots. Pb was accumulated in the highest concentration in the roots of all the four species, while Pkn accumulated Pb in the leaves as much as in the roots. Without mycorrhizal inoculation Pe accumulated Pb most among the four species, while Pkn with mycorrhizal inoculation accumulated Pb two times more than in the same species without mycorrhizal inoculation. It was concluded that Pag was the most effective species among the four poplar species in Cd absorption from contaminated soil, and that Pe instead effectively absorbed Pb. Mycorrhizal inoculation increased the Cd accumulation in the tissues by four times in Pag and also increased Pb accumulation by two times in Pkn, with leaves being the major sites of metal accumulation. It may be possible to use these two poplar species in remedying the metal in the soil through the raking and removing the litter out of the contaminate site.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.363-370
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• 2014

Various ecosystem carry out fundamental function of material circulation and energy flow through interrelationship with many environmental factors. Therefore, it is crucial to scientifically understand the value of nature to deduce correlation between environmental factor and change of ecosystem function. In this study, we determined the accumulated ecosystem carbon and characteristics of soil respiration on grassland vegetation in Namahangang basin in Namhangang Basin. It was found that the rate of soil respiration was highly correlated with the soil temperature in all communities. The measured soil respiration rates were $1,539mgCO_2\;m^{-2}h^{-1}$, $1,200mgCO_2\;m^{-2}h^{-1}$, $1,215mgCO_2\;m^{-2}h^{-1}$ in Miscanthus sacchariflorus, Phragmites japonica, Salix koreensis communities, respectively. Also, carbon quantities accumulated in litter and soil layers were $40.6tCha^{-1}$ (1.9+38.7), $46.9tCha^{-1}$ (43.0+3.9), $31.2tCha^{-1}$ (28.9+2.3) in M. sacchariflorus, P. japonica, S. koreensis communities, respectively.

• Journal of Wetlands Research
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• v.15 no.3
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• pp.347-356
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• 2013

To provide the information for the wetland management considering the water treatment ability of macrophytes, the growth characteristics and primary production by reed (Phragmites australis) and cattail (Typha angustifolia), and the decomposition rate of organic matter produced were investigated in two sub-wetlands (Banweol and Donhwa wetlands) of the Sihwa Constructed Wetland (CW) with different chemistry of inflows. The shoot height of P. australis and Typha angustifolia began to increase in March, and reached its peaks in July and August (340cm and 320cm, respectively). The shoot density of P. australis ranging $100{\sim}170EA/m^2$ was higher than that of T. angustifolia (max. $78EA/m^2$). Standing biomass of P. australis ranged from $1,350{\sim}1,980gDM/m^2$, with maximal biomass in Banwol Upper Wetland. And it was larger in upper wetlands than lower wetlands. On the other hand standing biomass of T. angustifolia ($1,940gDM/m^2$) was similar to that of P. australis in Banwol Upper Wetland. Primary productivity of P. australis was in the order of Banwol Upper Wetland ($2,050gDM/m^2/yr$) > Donghwa Lower Wetland ($1,840gDM/m^2/yr$) > Banwol Lowerr Wetland ($1,570gDM/m^2/yr$) ${\fallingdotseq}$ Donghwa Lower Wetland ($1,540gDM/m^2/yr$), and that of T. angustifolia ($2,210gDM/m^2/yr$) was higher than P. australis. Annual production of organic matter produced by P. australis and T. angustifolia was 845 ton DM/yr (423 ton C/yr), and about 90% was comprised of that by P. australis. From the litter decomposition rate (k) (P. australis: leaf 0.0062/day, stem 0.0018/day; T. angustifolia: leaf 0.0031/day, stem 0.0018/day), leaf was rapid degraded compare to stem in both P. australis and T. angustifolia. The litter decomposition rate of leaf was two times rapid P. australis than T. angustifolia, whereas that of stem was same in both. Annual litter decomposition amount of P. australis than T. angustifolia was 285 ton C/yr(67.3% of organic matter produced by macrophytes), indicating that 32.7% of organic matter produced by macrophytes is accumulated in the Sihwa CW.

• Development and Reproduction
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• v.22 no.1
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• pp.85-94
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• 2018

Endocrine disruptors have been concerned in toxicology but now challenged as physiological point especially concerned with exposing dose and period. In this study the low-dose chronic administration of di(2-ethylhexyl) phthaltae (DEHP) during reproductive period was examined to evaluate the possible roles. Adult male and female CD-1 mice were exposed to DEHP with drinking water containing $133{\mu}g/L$ and $1,330{\mu}g/L$ DEHP in water according to OECD 433 guide line and sacrificed just after weaning. The weights of uterus and ovary were decreased by drinking of $1,330{\mu}g/L$ DEHP water. There was not adverse effects on either accumulated mating rate and mating rate depend on estrus stage, pregnancy duration, and sex ration at birth. However, the accumulated rate of successful delivery and litter size were significantly high at $1,330{\mu}g/L$ DEHP water. The number of epididymal sperm was significantly increased by drinking of $1,330{\mu}g/L$ DEHP water. In addition, the number of follicles (primary, secondary, tertiary) were more many than control at $1,330{\mu}g/L$ DEHP water drunk mother. Though further studies are needed to identify what are the mechanism of DEHP in folliculogenesis and spermatogenesis. From this study we firstly report the effect of low-dose chronic administration of DEHP with drinking could change the ovarian follicle population size and spermatogenesis rate. Put together, those finding is different from previous high-dose effects and suggest the physiological role of DEHP in gonads and uterus.

• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.537-546
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• 2017

This study aims to develop the floating debris detection algorithm using a Unmanned Aerial Vehicle (UAV) and multispectral sensors. In addition, the occurrence range of floating debris was estimated by applying the algorithm. An aerial photograph using an unmanned aerial vehicle was used to generate an orthoimage that can calculate the area. A spectrum survey of water, plants litter, polystyrene foam etc. was conducted. After obtaining spectroscopic characteristics of floating debris and water, the River Floating Debris (RFD) index was calculated. And we detected the floating debris through band combination of sensor using RFD. As a result of the RFD application, accumulation zone of floating debris was confirmed at three sites in the orthoimage. It was estimated that a lot of floating debris was accumulated at 0.82 ha ($8,200m^2$), which is corresponding to 3.6% including the accumulation zone.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.2
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• pp.127-132
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• 1983

An investigation was performed to reveal the relation between production and decomposition of the Miscanthus sinensis and Arundinella hirta grasslands in Mt. Kwanak. 1. The total annual litter productions of M. sinensis grassland A, B and A, hirta grassland were 2,267.12, 943.44 and 1,228.45 g/m$^{2}$, respectively. 2. The decay constants of litters of M. sinensis grassland A, B and A. hirta grassland were 0.732, 0.411 and 0.877. 3. The time required for the decomposition of half of the accumulated organic matter of M. sinensis A,B and 4. hirta were 0.9, 1.7 and 0.8 years, for 95% of elimination 4.1, 7.3 and 3.4 years, and for 99% of elimination 6.8, 12.2 and 5.7 years respectively. 4. The decomposition rate of grass litters was affected by the soil water content and grass species.

• Development and Reproduction
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• v.21 no.2
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• pp.121-130
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• 2017

4-Nonylphenol (NP) is a surfactant that is a well-known and widespread estrogenic endocrine disrupting chemical (EDC). Although it has been known that the affinity of NP to ERs is low, it has been suggested that low-dose NP has toxicity. In the present study, the endocrine disrupting effects on reproduction, and the weight of gonads, epididymis, and uterus were evaluated with the chronic lower-dose NP exposing. This study was designed by following the OECD test guideline 443 and subjected to a complete necropsy. In male, NP had an effect on the weight of the testis and epididymis in both $F_0$ and $F_1$. In females, NP decreased the weight of ovary and uterus in $F_0$ but not in pre-pubertal $F_1$ pubs. Fertility of male and female in $F_0$ or $F_1$ was no related with NP administration. The number of caudal-epididymal sperm by body weight (BW) was not different between groups in both $F_0$ and $F_1$. Besides, the difference of the sperm number between generations was not detected. The number of ovulated oocytes was similar between groups in $F_0$, but significantly decreased in NP 50 group of $F_1$. The litter size and sex ratios of offspring in $F_1$ and $F_2$ were not different. The accumulated mating rate and gestation period were not affected by the NP administration. Those results shows that chronic lower-dose NP administration has an effect of endocrine disruptor on the weight of gonads and epididymis of $F_0$ and $F_1$ but not in reproduction. Based on the results, it is suggested that chronic lower-dose NP exposing causes endocrine disruption in the weight of gonad and epididymis but not in the reproductive ability of next generations.

• Korean Journal of Environmental Biology
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• v.25 no.3
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• pp.197-204
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• 2007

Diversity, production and nutrients concentrations of mushroom in a pitch pine forest (Pinus rigida) were studied from March through November 2000 in Kongju, Chungnam Province. Fifteen $2{\times}2m$ permanent quadrats were established randomly in the study area. 32 species of mushrooms were identified in the permanent quadrats during the study period. Although mushrooms occurred from June to October, the heighest diversity and biomass production occurred in August and September. Seasonal dominant species were Collybia confluens in July, Cantharellus lutescens in August and September, respectively. Annual production of mushrooms were 12.13kg $Dwha^{-1}yr^{-1}$. Seasonal production was 0.71kg $Dwha^{-1}$ for July, 3.95kg $Dwha^{-1}$ for August and 6.92 kg $Dwha^{-1}$ for September, respectively. Average concentrations of N, P, K, Ca and Mg in mushrooms was $38.81{\pm}4.82, \;0.90{\pm}0.44,\;28.47{\pm}7.81,\;0.24{\pm}0.16\;and\;0.76{\pm}0.26mg\;g^{-1}$, respectively, which were much higher than those in leaf litter and soil of the study site. Amount of N, P, K, Ca and Mg accumulated in mushrooms in 2000 was 463.41, 10.26, 345.21, 3.14 and $8.99g\;ha^{-1}yr^{-1}$, respectively.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.295-303
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• 2000

The water clarification efficiency was examined in a shallow wetland where dense vegetation was formed naturally in an abandoned paddy field. And, also two enclosure experiments were carried out to measure the effects of materials exchange between sediment and the overlying water with the existence of vegetation and accumulated litter. The hydraulic retention time of wetland was regulated in 1.2 day. The removal rates of SS (56%) and $NO_3-N$ (61%) were high, considering its short retention time. However, removal efficiencies of VSS (28%), COD (14%), DOC (1%),and TP (0.2%) were relatively lower. This low removal efficiencies were thought to be due to the release of dissolved form of organic matter and phosphorus from the sediment. Most of constituents except nitrate were higher in the enclosure at the beginning of enclosure installation than that of the outflowing water from wetland. And then, it has fluctuated and decreased with time. The wetland was in equilibrium state of settling, accumulation of organic debris, and regeneration of dissolved material from sediment. So ultimately high primary production by dense vegetation in the wetland may be the reason of unfavorable or low treatment efficiency of wetland after many years of operation for wastewater treatment. However, the water quality of effluent from the wetland showed smaller variation and better condition than that of inflow, especially during storm events. It can be concluded that this wetland is suitable for the improvement of water quality from nonpoint sources.