• Korean Journal of Plant Resources
• /
• v.21 no.2
• /
• pp.162-170
• /
• 2008

The purpose of this study was to suggest the raw data on establishing the domestic wetland conservation plan. The results of this study were as follows. The vascular plants were summarized as 201 taxa in Ahnshim wetland; 57 families, 154 genera, 179 species and 22 varieties. The rare and endangered plant designated by Korea Forest Service was Hydorcharis dubia. In the wetland plants, the emerged plants were showed Typha angustata, Beckmannia syzigachne, Zizania latifolia, Phragmites communis, Persicaria thunbergii, Oenanthe javanica and Veronica undulata, and the submerged plants were Potamogeton crispus, Vallisneria asiatica, Hydrilla verticillata, Ceratophyllum demersum and Myriophyllum verticillatum. And the floating leaved plants were confirmed Potamogeton distinctus, Hydrocharis dubia, Nelumbo nucifera and Nymphoides peltata, and the floating plants were Salvinia natans, Spirodela polyrhiza and Lemna paucicostata. The naturalized plants were 33 taxa; Avena fatua, Dactylis glomerata, Rumex crispus, Rumex conglomeratus, Amaranthus retroflexus, Lepidium apetalum, Tlaspi arvense, Descurainia pinnata, Potentilla supina, Vicia villosa, Robinia pseruo-acacia, Amorpha fruticosa, Trifolium repens, Medicago sativa, Ailanthus altissima, Euphorbia supina, Oenothera lamarckiana, Quamoclit angulata, Ipomoea purpurea, Solanum nigrum, Veronica perisca, Helianthus tuberosus, Ambrosia artemisifolia var. elatior, Xanthium strumarium, Erigeron annuus, Erigeron canadensis, Conyza sumatrensis, Senecio vulgaris, Bidens frondosa, Tagetes minuta, Taraxacum officinale, Taraxacum laevigatum and Sonchus oleraceus.

• Korean Journal of Environmental Agriculture
• /
• v.22 no.2
• /
• pp.153-165
• /
• 2003

This study was conducted to get some information on plants abilities to enhance water purification and to find out away to conserve the ecosystem in Mankyeong river. Vegetation were surveyed at 4 sites pointing by 1:5,000 topographical map, from June 2001 through March 2002. T-N content in water were high in all sites of Mankyeong river, the average T-N levels were 8.59 and 17.23 mg/L, summer and winter, respectively. The average T-P level during summer was 0.47 mg/L but that was 1.79 mg/L during winter. The BOD level in Mankyeong upstream ranged from 0.95 to 2.57 mg/L which would be in I or II grade according to water quality criteria by Ministry of Environment but BOD level in Mankyeong downstream ranged from 6.87 to 9.72 mg/L. The plant species of river flora were found 251, 98 and 85, upstream midstream and down stream, respectively. Among the surveyed plants, Ceratophyllum demersum, submerged plant and Nuphar subinteperrimum took up higher contents of phosphate and nitrogen than other piano. The Phragmites communis and Zizania latifolia having much biomass were thought to be suitable plants for enhancement of e natural water purification.

• Applied Microscopy
• /
• v.32 no.4
• /
• pp.319-327
• /
• 2002

Salvinia natans, an unique water fern having a small rootless body, developed three different types of trichomes throughout the plant. The most peculiar type exhibiting rows of obvious, whitish, multicellular trichome clusters was noticed in the upper surface of the floating leaves. Eight to ten branches within a cluster extended ca. $370{\sim}420{\mu}m$ from the leaf surface. No stalk cell was found, however, four large epidermal cells were discernable at the base of four central branches in the cluster. Each branch consisted of $8{\sim}10$ obliquely-oriented small cells that gradually decreased in size toward the branch tip. The second type was found in the lower surface of the floating leaves, stems, and sporocarps. Multicellular uniseriate trichomes, ca. $430{\sim}980{\mu}m$ long, were distributed all over these structures. The tip of trichome was acicular, but a semi-spheric protuberance of approximately $24{\sim}32{\mu}m$ in diameter occurred at the base of each trichome. The protuberance appeared to be firmly attached to the side of the basal cell, however, internal connection to the trichome cell itself was uncertain. The third type was similar to the second in that multicellur uniseriate trichomes with acicular tip and a protuberance at the base were present. However, the trichomes were considerably long relative to the second type, and only occurred along the surface of highly dissected, submerged leaves. A majority of the trichomes exceeded more than 2 mm in length that hung downward in the water. Regardless of trichome type, all trichomes contained a huge central vacuole with very thin cytoplasm, resulting from the fusion of several vacuoles during early trichome development. The various densely-distributed trichomes formed in Salvinia natans probably play an important role in plant buoyancy.

• Korean Journal of Environmental Biology
• /
• v.40 no.3
• /
• pp.341-351
• /
• 2022

Among various environmental stresses, humid stress lacks mechanisms and biochemical understanding compared to drought, low temperature, and high salt stresses. The aim of this study was to investigate enzyme activity of field crops under humidity stress. Results of this study could be used as basic data for understanding humidity stress and early diagnosis. Growth and enzyme activities of sesame, perilla, red beans, sorghum, and beans as major field crops in Korea when flooded were investigated. It was confirmed that growths of both shoots and roots were retarded. In plants, anaerobic fermentation occurred due to flooding stress, which increased the activity of alcohol dehydrogenase (ADH) compared to the control group. Increases of reactive oxygen species (ROS) were also observed. All flooded plants showed increased peroxidase (POD) activity and lipid peroxidation. Their dyeing strength was darker than that of the control group, even in 3,3'-diaminobenzidine (DAB) staining. Since enzyme activity changes in plants appear relatively faster than changes in phenotype at the ground level, they could be used as biomarkers for early diagnosis of humidity stress in crops.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.4
• /
• pp.657-663
• /
• 2012

To evaluate effects of water temperatures on nutrient releases of submerged plants in lake reservoir, COD, T-N and T-P releases of submerged plants were investigated for 60 days under different incubation temperatures ($5^{\circ}C$ and $25^{\circ}C$) in columns. The amounts of COD releases by Carex dimorpholepis were $60.4mg\;L^{-1}$ at $5^{\circ}C$ and $78.0mg\;L^{-1}$ at $25^{\circ}C$. In Miscanthus sacchariflorus, the amounts of COD releases were $62.5mg\;L^{-1}$ at $5^{\circ}C$ and $70.5mg\;L^{-1}$ at $25^{\circ}C$. The amounts of T-N releases in Carex dimorpholepis at $5^{\circ}C$ and $25^{\circ}C$ were 45.8 and $60mg\;L^{-1}$, respectively. In Miscanthus sacchariflorus, the amounts of T-N releases were $55.7mg\;L^{-1}$ at $5^{\circ}C$ and $61.0mg\;L^{-1}$ at $25^{\circ}C$. At $5^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 5.65 and $7.10mg\;L^{-1}$, respectively. At $25^{\circ}C$, the amounts of T-P releases in Carex dimorpholepis and Miscanthus sacchariflorus were 8.70 and $8.18mg\;L^{-1}$, respectively. In the column experiment, the amounts of COD, T-N and T-P releases by submerged plants at $25^{\circ}C$ were generally higher than those at $5^{\circ}C$.

• Korean Journal of Environmental Agriculture
• /
• v.16 no.1
• /
• pp.7-13
• /
• 1997

Tomatoes are flooded differently 0, 5, 10 and 15 ㎝, according to the developing stages such as transplanting stage under the condition of green house. Along with this, they are treated according to the time condition such as 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. As the depth of flooding got deeper and the hours got longer, plant height, number of leaves, shoot and root decreased significantly. Flowering was possible for 24 hours in the flooding of 0 ㎝, for 6 hours in $5{\sim}10$ ㎝, but not possible after 6 hours in 15 ㎝. Without regard to the depth of flooding, adventitious root came into being before or after 48 hours of the treatment. Root activity diminished gradually as hours of treatment went by, but diminished rapidly over the depth of 5 ㎝. Chlorophyll content decreased similarly as in the case of root activity. Diffusion resistance of stomata cell increased as hours of treatment passed and depth increased. Photosynthesis and respiration diminished according as the hours and depth of treatment increased. Respiration diminished a little gradually but photosynthesis weakened greatly as the depth of treatment became greater and after 48 hours of treatment. Diseases occurred remarkably in proportion to the depth of treatment and the increase of hours. The possibility of preventing by means of insecticide treatment showed the same tendency as in the seedling stage. But its effect was not significant. After 120 hours yields could not be expected because tomatoes died without regard to the depth of flooding. Instead of the depth, numbers of fruits per plant decrease of individuals or variation of average weight of a fruit was recognized. Especially average weight increased in accordance with the increase of the depth. There was positive correlation between all the characters, such as plant height, number of leaves, fresh weight, chlorophyll content, root activity and yield traits, but negative correlation between these and epinastic curvature, diffusion resistance and adventitious root.

• Korean Journal of Environment and Ecology
• /
• v.21 no.6
• /
• pp.494-505
• /
• 2007

This study was carried out targeting the intertidal zone and estuary area of Anseo port in Saemangeum reclamation zone from 2003 to 2004, to analyze how reclamation affects the distribution of vegetation and soil properties. The plant growing in these survey areas was all halophytes: the vegetation on the intertidal zone consisted of simply 3 species of halophyte, and vegetation on the high tide zone and estuary area consisted of 9 and 8 species respectively, showing a more varied aspect than the intertidal zone. As for the plant species distribution, the predominant species for the intertidal zone were Suaeda maritima, Limonium tetragonum and Suaeda japonica; the predominant species for the slope zone of estuary were Suaeda maritima, Limonium tetragonum and Aster tripolium, and the predominant species for the inundation zone of estuary were Kochia scoparia var. littorea. At the analysis result of soil chemical properties, it was discovered that the appearance of the plant species was made at some spots on the intertidal zone whose electrical conductivity(EC), $Na^+,\;and\;Cl^-$ were relatively lower. EC of between the plant species was similar in the same zone, however EC was distinctively different between the same species in the different zone. Our study found out that whether the occurrence of the plant species is possible or not was decided by the difference in soil properties. This study results suggest that the distribution of vegetation is influenced by soil environment in that the appearance of the plant species on the intertidal zone and estuary area is differentiated by soil texture and soil chemical properties.

• Journal of Korean Society of Environmental Engineers
• /
• v.35 no.4
• /
• pp.283-288
• /
• 2013

To evaluate the ability of the submerged plant, Ceratophyllum demersum's (C. demersum) to remove nutrients and to inhibit growth of cyanobacteria, a total of 6 mesocosms were conducted in a batch reactor for 9 days. From the 84 hr of the experiment, C. demersum was stabilized and showed daily cycle trends according to changes in pH and DO levels. The concentration of nutrients, $NH_3{^+}$, $NO_3{^-}$ and $PO_4{^3}$ continuously decreased until 9 days of the experiment, with the rapid decrease in nutrient concentration for the first 24 hours. High correlation coefficient ($r^2{\geq}0.96$, p<0.001) between the amount of C. demersum's biomass per unit area and the nutrients removal level were derived, and greater C. demersum's biomass per unit area showed higher removal efficiency of nutrients. However, there were differences in the C. demersum's activity level between batch reactors with higher and similar density of the C. demersum, but nonetheless water purification effect appears to have a significant influence due to attached algae and microorganisms. The growth rate of harmful cyanobacteria, Microcystis aeruginosa (M. aeruginosa) with C. demersum's density of 2,500 g $fw/m^2$ (100% of cover degree) was 0.31 /day, compared to the growth rate of 0.47 /day for the control group (0% of cover degree). In terms of number of cells, the control group had 1.7 times higher number of cells than the experimental group, proving that C. demersum has the ability to inhibit the growth of harmful cyanobacteria.

• Journal of Life Science
• /
• v.25 no.1
• /
• pp.37-43
• /
• 2015

We have investigated the effects of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), indole-3-acetic acid (IAA) and methyl jasmonate (MeJA) on the development of aerenchyma in the primary root of maize (Zea mays). Because plant hormones affected the longitudinal organization of the primary root, we need an indicator to direct the positions for comparison between control and hormone-treated roots. Therefore, the zones of the maize primary root were categorized as PR25, PR50 and PR75, where each value indicates the relative position between the root tip (PR0) and the base (PR100). Aerenchyma was not observed at PR25 and PR50 and rarely found at PR75 in the cortex of control roots. The aerenchymal area at PR75 increased in the presence of the ethylene precursor ACC or a natural auxin IAA. On the other hand, MeJA differentially acted on non-submerged and submerged roots. Exogenously applied MeJA suppressed the aerenchyma formation in non-submerged roots. When the primary root was submerged, aerenchymal area expanded prominently. The submergence-induced aerenchyma formation was amplified with MeJA. Lateral root primordia have been known to inhibit aerenchymal death of surrounding cells. All the three hormones stimulating aerenchyma formation as described above did not restore the inhibition caused by lateral root primordia, suggesting that the inhibitory step regulated by lateral root primordia can be located after hormonal signaling steps.

• Journal of Wetlands Research
• /
• v.6 no.3
• /
• pp.107-118
• /
• 2004

The flora of the vascular hydrophytes and hygrophytes and the change of flora according to the fluctuation of the water level before and after flooding were investigated from September 2002 to October 2003 in Woopo Wetland and Topyeong Stream, Changnyeong-gun, Gyeongsangnam-do, Korea. The flora of the Woopo, Mokpo, Sajipo, Jokjibyeol, Topyeongcheon Upstream, and Topyeongcheon Downstream were composed of 256, 242, 265, 177, 201, and 180 taxa, respectively. The flora of total study area was 86 families, 232 genera, 302 species, 42 varieties, 6 form, or total 350 taxa. Among them, hydrophytes, hygrophytes, and others were 36, 96, and 218 taxa, respectively. The life form of the vascular hydrophytes was classified as 19 taxa of emergent plants, 6 taxa of floating-leaved plants, 4 taxa of free-floating plants, and 7 taxa of submersed plants. The specified wild plants designated by the Korean Association for Conservation of Nature, Ministry of Forest, and Ministry of Environment were Euryale ferox, Hydrocharis dubia, Persicaria amphibia, Acorus calamus var. angustatus. And Aristolochia contorta was distributed in the study area. The floras of the naturalized plants of the Woopo, Mokpo, Sajipo, Jokjibyeol, Topyeongcheon Upstream, and Topyeongcheon Downstream were composed of 27, 25, 35, 21, 26 and 24 taxa, respectively. The flora of the naturalized plants of total study area was 43 taxa, this equalled 12.3% of total vascular plants in the study area. And 165~244 taxa were surveyed in the each study area before flooding, total 299 taxa, and 86~212 taxa after flooding, total 299 taxa. Among them, hydrophytes, hygrophytes, and others were 33 and 29, 93 and 83, 183 and 187 taxa before and after flooding, respectively. Before and after flooding, the species number of emergent plants, floating-leaved plants, free-floating plants, and submersed plants was nearly the same. It was guessed that vascular hydrophytes and hygrophytes adapted to fluctuation of the water level in the study area.