• Journal of Environmental Impact Assessment
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• v.29 no.3
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• pp.182-197
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• 2020

This study investigated the home range and characteristics of activities to contribute to the improvement of management techniques and the successful promotion of management policies of invasive nutria, which is a representative invasive species of South Korea. Six individuals were captivated for the study. Remote radio tracking on three of them was carried out followed by the analysis of the results. The average home range of the follow-up individuals were confirmed to be 0.043 ㎢ at MCP 95%, 0.085 ㎢ at K 95%. It was 0.018 ㎢ at K 50%, which is the core space. In 95% MCP, males exhibited the home range with 0.058 ㎢, showed wider home range 0.046 ㎢ than females who showed 0.012 ㎢, and showed a wider home range 0.015 ㎢ more at night than during the day. As a result of comparing the results of this study with the case studies of overseas studies, it is determined that the magnitude of the derived home range is the result of a stable habitat in which the procurement of food resources is smooth and human interference is limited. The daily moved distance of males was larger than that of females, with a maximum moved distance of 1,278 m per day. Activity at the study site is high from around sunset to around 6 A.M., 10 P.M., 7 P.M., 1 A.M., and 5 A.M., and high around sunrise and low during the daytime such as 2 P.M., which reflected the propensity of nocturnal animals to act. The results of this study on the home range and activity in nutria can be used as useful data forimproving the management of invasive alien species for the installation and operation of traps, the spatial setting of controlled areas, and the calculation of the amount ofresources together with a basic understanding of nutria's behaviors in South Korea.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.6
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• pp.77-91
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• 2013

The researcher noted the fact that wetland users are more and more diversified while people are more conscious of their ecological importance. Wetlands tend to be very sensitive in ecological terms, and therefore, they can hardly accommodate their users' needs indefinitely. With such basic perception in mind, the purpose of this study was to survey wetland users' eco-consciousness, determine their traits, analyze the corelation between their traits and preferences of wetland amenities, and thereby, provide the data useful to planning of an effective wetland management policy. To this end, the researcher sampled nation's largest wetland, Upo Marsh located in Changnyeong for a questionnaire survey. Wetland users' eco-consciousness was measured, using Dunlap's NEP (New Ecological Paradigm) approved by many researchers. Wetland users' preferences of the wetland amenities were measured, centered around 11 amenity types observed commonly at the domestic wetlands. As a result of the survey conducted in October, 2012, a total of 228 effective samples were acquired. Wetland users' eco-consciousness was higher than normal, scoring 3.45 on the 5-point scale consisting of 5 sub-scales. In particular, users were more conscious of 'the possibility of an eco-crisis,' while being less conscious of 'ejection of exemptionalism.' As a result of classifying the users into 3 sub-groups in reference to their eco-consciousness and analyzing their preferences of amenities comparatively, significant differences were found in all 3 sub-areas. In particular, the sub-group most eco-conscious tended to prefer the learning amenities, but the least eco-conscious sub-group tended to prefer the utilities. As a result of the post-hoc test, it was found that most and normal eco-conscious sub-groups were more or less homogeneous, while the least eco-conscious sub-group was significantly different from the former 2 sub-groups in terms of eco-consciousness. As the wetland users were found to be diversified in terms of their eco-consciousness, it is necessary to plan the wetland management policies in consideration of such differences. However, it is perceived that the wetland amenities need to be built to meet the more eco-conscious users.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.1
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• pp.111-122
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• 2009

Abatements of TN and ${NO_3}^-$-N in a horizontal subsurface-flow wetland with litter layer on its surface were compared with those without one. The wetland was constructed in 2001 on floodplain of the Gwangju Stream which flows through Gwangju City in Korea. Its dimensions were 29m in length, 9m in width and 0.65m in depth. A bottom layer of 45cm was filled with crushed granites (15~40mm in diameter) and a middle layer of 10cm had pea pebbles. An upper layer of 5cm contained coarse sands. Reeds (Phragmites australis) growing in natural wetlands were transplanted on its surface. Water of the stream was channelled into the wetland by gravity flow and its effluent was discharged back into the stream. Average Litter layer of 12.2cm was formed on its surface in 2007. The layer and above-ground parts of reeds were eliminated in April 2008. Volumes and water quality of influent and effluent of the wetland were analyzed from May to November in 2007 and 2008, respectively. Inflow into the wetland both in 2007 and 2008 averaged approximately 40$m^3$/day and hydraulic residence time both in 2007 and 2008 was about 1.5days. Influent TN concentration in 2007 and 2008 averaged 3.96 and 3.89mg/L, respectively and average influent ${NO_3}^-$-N concentration in 2007 and 2008 was 2.11 and 2.05mg/L, respectively. With a 0.05 significance level, influent concentrations of TN and ${NO_3}^-$-N, temperatures and pH of effluent, and heights and stem numbers of reeds showed no difference between the wetland with litter layer and without one. TN retention in the wetland with litter layer and without one averaged 64,76 and 54.69%, respectively and ${NO_3}^-$-N removal averaged 60.83 and 50.61%, respectively. Both TN and ${NO_3}^-$-N abatement rates in the wetland with litter layer were significantly high (TN abatement: p<0,001, ${NO_3}^-$-N abatement: p=0.001) when compared with those without one. The subsurface-flow wetland having litter layer on its surface was more efficient for TN and ${NO_3}^-$-N removal.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.422-431
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• 2017

The biogeochemical information of riverine organic matter gives a detailed and integrated recording of natural and anthropogenic activity within a watershed. To investigate the changes in quality and quantity of organic carbon transporting from mountain to ocean via river channels, we estimated the concentrations of dissolved (DOC) and particulate organic carbon (POC), and then traced the source origin of POC using stable carbon isotopes ratio before and after summer rainfalls in the Tamjin River and Ganjin Bay, Korea. Along the small watershed, a total of 13 sites including headwaters, dam reservoir, river and estuary were established for the study. We found some interesting findings in the aspect of distribution of DOC/POC concentration changing their origin sources dynamically flowing downstream. In particular, the river channel transport downstream mainly DOC to river mouth, although upper dam reservoir increased POC concentration by phytoplankton production in summer. Whereas, in the river mouth and estuary, POC was dominated not only by local supply from nearby reed saltmarsh, but also by marine phytoplankton production, respectively. The findings can contribute to increasing the understanding of riverine organic carbon transport in upper large dam and lower open estuary system.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.690-706
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• 2019

Paddy fields play an important role in the biodiversity conservation of agroecosystems as man-made wetlands. This study focused on the floristic composition and characteristics of paddy fields in South Korea. The flora surveys were conducted in 33 areas in nine provinces at two times (June and August) in 2016. The results showed that the vascular plants of the paddy fields in South Korea included 389 taxa, composed of 51 families, 219 genera, 350 species, four subspecies, 30 varieties, and five forms. Among the 51 families, Gramineae was the most diverse in species (76 taxa), followed by Compositae (61 taxa), Leguminosae (32 taxa), Cyperaceae (27 taxa), Polygonaceae (15 taxa), and Scrophulariaceae (12 taxa). Based on the occurrence frequency of each species, Digitaria ciliaris (Retz.) Koel. (100%), and Echinochloa crus-galli (L.) P.Beauv. (100%) were the highest, followed by Acalypha australis L. (97.0%), Bidens frondosa L. (97.0%), Alopecurus aequalis Sobol. (97.0%), Rorippa palustris (Leyss.) Besser (93.9%), Ludwigia prostrata Roxb. (93.9%), Lemna perpusilla Torr. (93.9%), Mazus pumilus (Burm. f.) Steenis(90.9%), Rorippa palustris(Leyss.) Besser(87.9%), Eclipta prostrata(L.) L.(87.9%), Commelina communis L.(87.9%), Artemisia princeps Pamp.(84.8%), Erigeron annuus (L.) Pers.(84.8%), Cyperus microiria Steud.(84.8%), and Aneilema keisak(Hassk.) Hand.-Mazz. (81.8%). The biological type of paddy fields in South Korea was determined to be Th-R₅-D₄-t type. Rare plants were found in six taxa: Aristolochina contorta Bunge, Penthorum chinense Pursh, Sagittaria sagittifolia subsp. leucopetala (Miq.) Hartog, Ottelia alismoides (L.) Pers., Pseudoraphis ukishiba Ohwi, and Acorus calamus L. Eighty taxa contained naturalized plants composed of 15 families, 54 genera, 76 species, three varieties, and one form. The urbanization and naturalization indices were 24.8% and 20.6%, respectively.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.4
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• pp.43-61
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• 2017

The wetlands are facing environmental changes such as desiccation that occurs with the passage of time and reduced ecosystem services from wetlands in the city. In order to maintain the ecosystem services provided by wetlands in urban areas, a system thinking about the trade-off phenomenon of ecosystem services occurring as the wetlands undergo environmental changes is needed. Therefore, the purpose of this study is to develop strategies for wetland design using system thinking approach to enhance the resilience of ecosystem services degraded by the desiccation of wetlands and other disturbances. The objectives of this study include the system boundary and variables. Second, analyzing the dynamics of wetland design strategy. Third, it analyzes the trade-off phenomenon of ecosystem services in terms of the hydrology, hydric soil, and plants strategies to mitigate these effects. Fourth, wetland basic design to improve the resilience of ecosystem services. A wetland in Abuk-Mountain Neighborhood Park, Miryang-si, Gyeongsangnam-do, has been selected as a case study. Causal loop diagrams(CLDs) are used to analyze feedback in the wetland regime. In summary, hydrology, hydric soil, and plants is suggested as system boundaries to design plan. Design strategies for the wetland focused on robustness, redundancy, rapidity, and resourcefulness as a result of CLD analysis are first proposed in order to effectively maintain the wetland regime over the long term. Secondly, in a section related to hydrology, the CLD results show the trade-offs between provisioning-cultural services and regulating services. In order to control these services, a "water cycling system" has been implemented due to its strength in terms of robustness. The CLDs for hydric soil showed the trade-offs between regulating services and supporting services. An "installation of storm drainage for maintaining water levels" was selected due to the strength offered in terms of redundancy and rapidity. The CLDs for plants showed the trade-offs between provisioning - cultural services and regulating services. In order to control the strategic points, the "planting of indigenous vegetation" was suggested given the strength in terms of redundancy. In this study, a wetland design method is proposed that can improve the resilience of wetland ecosystem services by analyzing the dynamics overtime. The results of this research can theoretically be applied to help restore ecosystem services in wetlands using ecological landscape design. In addition, this study will contribute to reducing maintenance costs by improving wetland resilience.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.165-170
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• 2009

The increase in P availability to rice under flooded soil conditions involves the reductive dissolution of iron phosphate and iron (hydr)oxide phosphate. However, since $NO_3^-$ is a more favourable electron acceptor in anaerobic soils than Fe, high$NO_3^-$ loads function as a redox buffer limiting the reduction of Fe. The effect of adding $NO_3^-$ on Fe reduction and P release in paddy soil was investigated. Pot experiment was conducted where $NO_3^-$ was added to flooded soil and changes of redox potential and $Fe_2^+$, $NO_3^-$ and $PO_4^{3-}$ concentrations in soil solution at 10 cm depth were monitored as a function of time. Redox potential decreased with time to -96 mV, but it was temporarily poised at about 330${\sim}$360 mV when $NO_3^-$ was present. Nitrate addition to soil led to reduced release of $Fe_2^+$ and prevented the solubilization of P. Phosphate in pore water began to rise soon after incubation and reached final concentrations about 0.82 mg P/L in the soil without $NO_3^-$ addition. But, in the soil with $NO_3^-$ addition, $PO_4^{3-}$ in pore water was maintained in the range of 0.2${\sim}$0.3 mg P/L. The duration of inhibition in $Fe_2^+$ release was closely related to the presence of $NO_3^-$, and the timing of $PO_4^{3-}$ release was inversely related to the $NO_3^-$ concentration in soil solution. The results suggest that preferential use of $NO_3^-$ as an electron acceptor in anaerobic soil condition can strongly limit Fe reduction and P solubilization.

• Journal of the Korean Geographical Society
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• v.44 no.4
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• pp.481-496
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• 2009

Every coastal area exhibits its own unique landscape owing to the combination of the natural and cultural processes. Coastal barrier islands well show the cultural aspects of American coastal landscapes. Some 47% of barrier island area was occupied by urban and built-up area in New Jersey, while some 5% in Georgia. Tourism-related development is back to in the mid 19C. in N.J. due to the closeness to heavily populated areas such as New York and Philadelphia. Developments without proper understanding the nature of coastal processes caused New Jerseyization, the destruction of the beauty or naturalness. It was mainly due to the lack of growth-control policies and the foresight for the future coast in the processes of legislation. North Carolina's islands experienced an increase of 269% in urbanized acreage between 1956 and 1976. However, N.C. exercised her wisdom to recover the naturalness of the coastal environs: all engineering structures are banned on the beaches. Nine out of 13 barrier islands in Georgia exist in the wilderness condition owing to her unique history. The remaining islands still experienced the least development. After the Civil War most of Georgian islands were owned by rich families and maintained as wilderness. In the 1970s most of the uninhabited islands were sold or donated to research institutes or governmental agencies.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.184-187
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• 2013

The Four Major Rivers Restoration Project of is the multi-purpose green growth project in South Korea. Some of the project was progressed by K-water and was declared complete on October 21, 2011. The Four Rivers Restoration Project of Korea was designed to be a packaged project that aims to resolve water-related problems such as floods and droughts and revitalize Korean public spaces near the water. K-water have applied the latest ICT(Information and Communication Technology) for the operating management of 4 Rivers Project facilities. We also have applied ICT for integrating drinking water production facilities. Applying these ICT, we have many experience for integrated water resources management, so we proposed. The first is that the big data collected should be analyzed for making decisions and taking actions while considering multiple viewpoints of how water should be managed. The second is that the new MMI(Man Machine Interface) program should be developed to use domestic needs and promote ease of maintenance for the integrated operation. The third is that the standardization of communication protocol is needed for seamless communication between equipments.

• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.91-103
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• 1994

The floristic characteristics and ecological conservation measures for the plant resources of the Tokyusan National Park. Chollapuk-do, Korea were discussed. The field works was done for three times in nine major areas from April to July, 1993. The total number of vascular plants in this area were summarized as 97 families, 297 genera, 469 species and 541 kinds. The nineteen kinds of artificially planted, twelve kinds of Korean endemics and sixteen kinds of Korean rare and endangered species in the area were revised and compiled in the list. The flora of the area were categorized into the Southern part of the Korean Region, where the species such as Quercus serrata. Fraxinus sieboldiana, Ilex macropoda, Lindera erythrocarpa, Lindera glauca, Rubus coreanus, Taxus cuspidata, Cephalotaxus koreana and Abies koreana were roled as major floristic components in the Korean Region and endemized in the southern part of Korea. The natural communities such as Adonis amurensis Community, Taxus cuspidata Community, Betula ermanii Community, Hemerocalis spp. Community, Rhododendron tschnoskii Community, Rhododendron schlippenbachii Community, Disporum ovale Community, Tricyrtis dilatata Community, and present natural distribution of Abies koreana, and swamp vegetation in Tumunsan areas, as well as upland grassland at the summit of Hyangchokpong were represented for their floristic values in the area. The fifteen kinds of medicinal plants such as Gastrodia elata, seven kinds of ornamental plants such as Adonis amurensis, and thirteen kinds of edible plants such as Ligularia fischeri are faced potentially in endangered from the outrageous collections by the local peoples. The Action Plan for the conservation management of the area which enables sustainable use by the local peoples must be established in the near future.