• Korean Journal of Plant Resources
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• v.21 no.2
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• pp.162-170
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• 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 Ecology and Environment
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• v.39 no.1 s.115
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• pp.85-92
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• 2006

To evaluate the primary production and nutrient uptake of macrophytes in Lake Paldang, this study investigate the vegetation areas of six dominant aquatic plants including Typha angustifolia, Zizania latifolia, Phragmites australis, Trapa japonica, Nelumbo nucifera and Savinia natans, and contents of carbon, nitrogen and phosphorus of each macrophyte. Total vegetation area of six dominant aquatic plants was 1.37 $km^2$. Among them, Typha angustifolia was the most wide-distributed species which occupied the 46.7% of total vegetation area. Littoral zone of South Han river had the largest vegetation area with 0.458 $km^2$, and North Han river, Kyungan river and confluence area in the order named. The results of the contents of carbon, nitrogen and phosphorus of macrophytes showed that the carbon contents of emergent macrophytes was higher than that of other life-forms. The nitrogen content of Salvinia natans, free-floating macrophyte was highest and that of Typha angustifolia, emergent macrophyte was lowest. The phosphorus content of Trapa japonica showed the highest content of phosphorus among six macrophytes and emergent macrophytes such as Zizania latifolia and Phragmites australis showed lower contents of phosphorus than other life-forms. The annual net primary production of macrophytes in Lake Paldang, 2004, was calculated as 758.4 ton C $yr^{-1}$ and the annual net nitrogen and phosphorus uptake of macrophyte was 16,921 kg $yr^{-1}$ and 1,841.0 kg P $yr^{-1}$ respectively. Comparing the total budget of organic carbon, nitrogen and phosphorus in Lake Paldang, the amount of primary production and nutrient uptake by macrophytes take a small portion in total budget implying macrophytes do not play an important role in budget of matters in river-type lake, Lake Paldang.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.1-9
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• 2015

Many irrigated and drainage canals, reservoirs, lakes, and rivers are choked by the explosive growth of aquatic weeds, resulting in enormous direct loss in Korea. Distribution of aquatic weeds and exotic invasive plant species in irrigation and drainage waterways, and riparian wetlands was reviewed to provide basic information for management of aquatic weeds and invasive plant species in wetlands. Dominant emergent weeds in canals, reservoirs and lakes were Phragmites communis, Leersia japonica, Zizania latifolia, Conyza canadensis, C. annuus, Rumex crispus, Panicum dichotomiflorum, Bidens frondosa, and Oenothera odorata. Dominant emergent weeds in wetlands of rivers include Digitaria sanguinalis, P. communis, R. crispus, Artemisia princeps, Humulus japonicus, Echinochloa crusgalli, B. frondosa, and Persicaria thunbergii. In irrigation and drainage canals and lakes, dominant submersed weeds were Hydrilla verticillata, Najas minor, Potamogeton malaianus, P. crispus, Ceratophyllum demersum, Myriophyllum verticillatum, Salvinia natans, and Trapa natans. Dominant exotic weeds in wetlands include Trifolium repens, O. odorata, C. annuus, B. frondosa, Avena fatua, Ambrosia artemisiifolia, X. strumarium, and P. dichotomiflorum. Approaches to aquatic weed control were mechanical, chemical and biological control techniques. Periodic monitoring of aquatic weeds and exotic weeds, and their integrated management studies are needed in waterways and riparian wetlands in Korea.

• Journal of Wetlands Research
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• v.16 no.2
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• pp.187-192
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• 2014

This study is on the characteristics of habitat use of Pheasant-tailed Jacana Hydrophasianus chirurgus in Upo-wetland from June to August in 2013. The purpose is population management of Pheasant-tailed Jacana. Four nests were founded which are located in $56.2{\pm}16.37m$ from the waterside. Pheasant-tailed Jacana made their nests above Euryale ferox which consists with water plants such as Salvinia natans, Spirodela polyrhiza, Ceratophyllum demersum, Hydrocharis duvia and so on. Human beings seem to be the biggest obstacle of their breeding, according to this, Pheasant-tailed Jacana moved their eggs. Only two out of four nests, they moved their eggs and the distance was 1 to 2 meters from the nests. Since plant community of Euryale ferox is extensively distributed and water level also keep stable in Upo-wetland, the number of Pheasant-tailed Jacana coming to Upo-wetland is expected to increase every year. In the past, the number of Pheasant-tailed Jacana coming to Korea was too little to include management plan, but now, we need to manage them because of their population growth and the regular advent.

• Journal of Wetlands Research
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• v.9 no.2
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• pp.45-55
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• 2007

Flora, actual vegetation map, distribution area by the life form, primary productivity and annual primary production by the vascular hydrophytes and hygrophytes were investigated in the Upo wetland, Changnyeong-gun, Gyeongsangnam-do, Korea from May 2005 to March 2006. The flora of Upo, Mokpo, Sajipo, Jokjibyeol, Topyeongcheon upstream, and Topyeongcheon downstream were composed of 263, 233, 244, 182, 190, and 178 taxa, respectively. The flora of total study area was 85 families, 224 genera, 287 species, 42 varieties, 4 form, or total 333 taxa. Among them, hydrophytes, hygrophytes, and others were 38, 108, and 187 taxa, respectively. The life form of the vascular hydrophytes was classified as 20 taxa of emergent plants, 6 taxa of floating-leaved plants, 5 taxa of free-floating plants, and 7 taxa of submersed plants, respectively. There were 27 plant communities including pure population, mixed population, and etc. It is also found that Trapa japonica-Ceratophyllum demersum community occupies 60.64 ha, the largest area, and Salvinia natans-Ceratophyllum demersum community 32.91 ha, Zizania latifolia community 30.05 ha, and that the area of free-floating plants was the largest as 172.6 ha(47.9%) on the basis of life form. Total annual primary production of the vascular hydrophytes and hygrophytes was 1,383.3ton. That of the emergent hydrophytes was the most as 564.1 ton(40.8%), and those of the free-floating, floating-leaved, and the submersed were 484.1 ton(34.9%), 146.7 ton(10.6%), and 1.3 ton(0.5%), respectively, and the hygrophytes was 182.1 ton(13.2%). Since most plant species are fairly adapted to the present marsh environment, bad influences and change of species composition are expected by the artificial influences on the wetland such as fragmentation, reclamation, and introduction of the exotic species. Therefore, schemes and counterplans for the conservation and preservation of the marsh are demanded.

• Korean Journal of Ecology and Environment
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• v.35 no.4 s.100
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• pp.273-284
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• 2002

During January 1998-October 1999, the impact of free-floating plants (FFP) on limnology of the wetland ecosystem was evaluated through the investigation of physicochemical characteristics of the Woopo Wetland along with in situ manipulation experiments of aquatic plants. Flooding events occurred in the wetland during the summer period (Jun.-Aug.) and water levels rose to 2-3 m due to precipitation from the catchment and inflow from the main channel of the Nakdong River. Physicochemical parameters and plankton dynamics in the wetland during the summer were greatly influenced by floods and growth of free-floating plants. Dissolved oxygen (Jun.-Sept., 4.5${\pm}$2.5 mg/1; Oct.-May, 8,1 ${\pm}$4.0 mg/1) and pH (Jun.-Sept., 6.9${\pm}$0.4; Oct.-May,7.4${\pm}$0.8) levels were significantly lower during the summer than any other seasons. Three types of enclosure experiments (100 L, treatments with floating plants, screened and opened) were conducted under the presence and absence of sediment for 15 days in the 1999 summer. The treatments with sediment had higher levels of nutrient concentrations than those of the others. Among the treatments with sediment, nutrient concentrations in the treatments with free-floating plants were higher than the others. Zooplankton communities in each treatment showed a similar variation, although the scale of zooplankton densities differed. Rotifer community dominated the zooplankton at the initial phase of the experiment, but decreased drastically along with an increase of cladoceran and copepod communities. In conclusion, low levels of dissolved oxygen and pH in the Woopo Wetland during the summer seemed to be caused by a proliferation of free-floating plants and active decomposition process at the bottom of the sediment.

• Korean Journal of Weed Science
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• v.12 no.2
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• pp.144-157
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• 1992

The study was conducted to compare the interprete methods and examine the feasibility of mixture use of oxyfluorfen and bensulfuron in controlling principal Paddy weeds, annuals and perennials. Application ratio of both chemicals were obtained from the combinations of 5 levels(0, 5, 10, 15, 20 g ai/ha) of each chemicals, respectively. All the treatments were applied at 5 days after transplanting and water was maintained at 3.0cm in depth. Shoot fresh-weight of weeds was assessed at 35 days after treatments. Data obtained was analysed by Colby, Isobole, Calculus, Regression and EQM method, respectively. The results from the analysis of variance on the principal weeds treated with oxyfluorfen and bensulfuron showed significant interactions at 1% level on both Echinochloa crus-galli and Eleocharis Kuroguwai, and total species at 0.5% level on both Potamogeton distinctus and Cyperus serotinus, but non significant on Scirpus juncoides and Sagittaria pygmaea. Thereafter, the results of the models applied to Echinochloa crus-galli, Eleocharis kuroguwai and total species were as follows ; 1. The Colby method gave values nearly identical to regression estimate method (both multiplicative models) as provided by Akobundu et al. The Colby method and Regression method indicated synergistic toward Echinochloa curs-galli, and total species, but antagonistic toward Eleocharis kuroguwai. 2. The Isobole method shows synergism on Echinochloa crus-galli at $ID_{50}$, and total species at $ID_{60}$ on Eleochari kuroguwai. 3. The Calculus method gave positive signs for the first differentiation and negative signs for the second differentiation except for some rates on Echinochloa crus-galli and total species, but reverse on Eleocharis kuroguwai. These result does not agree with the observed values. 4. ${\theta}$ value from the EQM method was greater than one at all combinations. This result was quite different from those of other methods. 5. The various models did not show the same results, but mixture of oxyfluorfen and bensulfuron tend to have synergistic effect. Weeding effect also was high. Treatment in terms of two chemical combination was expected to reduce rates, and to enhence weeding efficacy compared with single treatment.