This study was conducted to provide the basic information for making the plans for reasonable conservation of inland man-made wetlands by analysis the vascular plant and life form at Junam wetland where is ecological important such as bird`s home and wetland vegetation.
The vascular plants of four Junam wetland were recorded as total 323 taxa, 81 families, and 237 genera. The vascular plants by each wetland was 162 taxa, 58 families, 130 genera, 148 species, 2 subspecies, 1 forma, and 11 varieties at Dongpan reservoir, 226 taxa, 59 families, 170 genera, 204 species, 3 subspecies, 1 forma, 18 varieties at Junam reservoir, 117 taxa, 45 families, 97 genera, 107 species, 1 forma, and 9 varieties at Sannam reservoir, and 157 taxa, 46 families, 118 genera, 148 species, 1 subspecies, and 8 forma at Artificial wetland, respectively.
By life form, Therophyte had the highest ratio at four wetlands. Similarity index showed above 50% among Dongpan, Junam and Sannam, and that was below 20% between Artificial wetland and other wetlands. Rare plants were observed Hydrocharis dubia (Blume) Backer at Dongpan reservoir, Euryale ferox Salisb., Hydrocharis dubia (Blume) Backer and Aristolochia contorta Bunge at Junam and Sannam reservoir.
The specific plants by floristic region were 11 taxa including Salix chaenomeloides Kimura, Ulmus parvifolia Jacq., Euonymus japonicus Thunb., Actinostemma lobatum Maxim., Lysimachia barystachys Bunge, Nymphoides peltata (Gmel.) Kuntze, Artemisia selengensis Turcz. ex Besser, Poncirus trifoliata Raf., Melia azedarach L., Prunus davidiana (Carriere) Franch., Utricularia pilosa Makino at Dongpan reservoir, 13 taxa including Salix chaenomeloides Kimura), Ulmus parvifolia Jacq., Aristolochia contorta Bunge, Actinostemma lobatum Maxim., Peucedanum japonicum Thunb., Lysimachia barystachys Bunge, Nymphoides peltata (Gmel.) Kuntze, Sagittaria aginashi Makino, Nymphoides indica (L.) Kuntze, Prunus davidiana (Carriere) Franch., Hydrocharis dubia (Blume) Backer, Euryale ferox Salisb. at Junam reservoir, 8 taxa including Salix chaenomeloides Kimura, Aristolochia contorta Bunge, Nymphoides peltata (Gmel.) Kuntze, Sorghum nitidum var. majus (Hack.) Ohwi, Nymphoides indica (L.) Kuntze, Prunus davidiana (Carriere) Franch., Hydrocharis dubia (Blume) Backer, Euryale ferox Salisb. at Sannam reservoir, and 11 taxa including Nymphoides peltata (Gmel.) Kuntze, Potamogeton octandrus Poir., Sagittaria aginashi Makino, Cynodon dactylon (L.) Pers., Allium tuberosum Rottler ex Spreng., Ottelia alismoides (L.) Pers., Monochoria korsakowii Regel & Maack, Limnophila sessiliflora (Vahl) Blume, Ludwigia ovalis Miq., Hydrocharis dubia (Blume) Backer, Euryale ferox Salisb. at man-made wetland. The ratio of the specific plants by floristic region to total taxa were 6.8, 5.9, 6.8, 7.0 at Dongpan, Junam, Sannam and Artificial wetland, respectively.
The naturalized plants were 28 taxa including Rumex crispus L., Phytolacca americana L., Amorpha fruticosa L. and so forth at Dongpan reservoir, 38 taxa including Cerastium glomeratum Thuill., Solanum americanum Mill., Potentilla amurensis Maxim. and so forth at Junam reservoir, 12 taxa including Lepidium apetalum Willd., Erigeron annuus (L.) Pers., Erechtites hieracifolia Raf. and so forth at Sannam reservoir, and 26 taxa including Rumex acetosella L., Trifolium repens L., Ammannia coccinea Rottb. and so forth at artificial wetland, respectively. Naturalized ratio was 17.3%, 16.8%, 10.3%, and 16.6% at Dongpan, Junam, Sannam, and Artificial wetland, respectively. Most of the naturalized plants appeared to have invaded during the first period(1922-1963). Ⅴ type of the degree of naturalization showed the highest ratio at four study sites.
Hydrophyte were 22 taxa including Potamogeton distincuts A.Benn., Spirodela polyrhiza (L.) Sch., Hydrilla verticillata (L.f.) Royle and do forth at Dongpan reservoir, 28 taxa including Salvinia natans (L.) All., Euryale ferox Salisb., Nymphoides indica (L.) Kuntze and so forth at Junam reservior, 21 taxa including Trapa japonica Flerow, Hydrocharis dubia (Blume) Backer, Potamogeton crispus L. and so forth at Sannam, and 48 taxa including Marsilea quadrifolia L., Potamogeton crispus L., Ottelia alismoides (L.) Pers. and so forth at Artificial wetland, respectively.
The species of higher important value were Artemisia princeps Pamp., Panicum bisulcatum Thunb., Equisetum arvense L. at Dongpan reservoir, Hydrocharis dubia (Blume) Backer, Spirodela polyrhiza (L.) Sch., Zizania latifolia (Griseb.) Turcz. ex Stapf at Junam reservoir, Spirodela polyrhiza (L.) Sch., Leersia sayanuka Ohwi, Salvinia natans (L.) All. at Sannam reservoir, and Aneilema keisak Hassk., Nelumbo nucifera Gaertn., Eleocharis kuroguwai Ohwi at Artificial wetland, respectively.
Species diversity and dominance were 3.35 and 0.15 at Dongpan reservoir, 2.84 and 0.20 at Junam reservoir, 1.72 and 0.56 at Sannam reservoir, and 2.93 and 0.19 at Artificial wetland, respectively.