• Membrane and Water Treatment
• /
• v.14 no.4
• /
• pp.155-162
• /
• 2023

Global climate change and urbanization have various demerits, such as water pollution, flood damage, and deterioration of water circulation. Thus, attention is drawn to Nature-based Solution (NbS) that solve environmental problems in ways that imitate nature. Among the NbS, urban wetlands are facilities that perform functions, such as removing pollutants from a city, improving water circulation, and providing ecological habitats, by strengthening original natural wetland pillars. Frequent monitoring and maintenance are essential for urban wetlands to maintain their performance; therefore, there is a need to apply the Internet of Things (IoT) technology to wetland monitoring. Therefore, in this study, we attempted to develop a real-time wetland monitoring device and interface. Temperature, water temperature, humidity, soil humidity, PM1, PM2.5, and PM10 were measured, and the measurements were taken at 10-minute intervals for three days in both indoor and wetland. Sensors suitable for conditions that needed to be measured and an Arduino MEGA 2560 were connected to enable sensing, and communication modules were connected to transmit data to real-time databases. The transmitted data were displayed on a developed web page. The data measured to verify the monitoring device were compared with data from the Korea meteorological administration and the Korea environment corporation, and the output and upward or downward trend were similar. Moreover, findings from a related patent search indicated that there are a minimal number of instances where information and communication technology (ICT) has been applied in wetland contexts. Hence, it is essential to consider further research, development, and implementation of ICT to address this gap. The results of this study could be the basis for time-series data analysis research using automation, machine learning, or deep learning in urban wetland maintenance.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.35 no.6
• /
• pp.48-63
• /
• 2008

This research is to apply suitable natural ecosystem evaluation criteria in order to develop the ecosystem conservation, restoration and ways to build substitute habitats as a compensation plan for damaged soundly natural ecosystems in small-scale projects such as resource recovery facility, filtration, etc. The environmental ecology evaluation i.e. generally based on their actual vegetation, community structure, wildlife, water system survey were measured the primary plans for reflecting unique natural environment level of site. As a result, it is necessary to conserve the land in fallow type of wetland, good conservative condition of deciduous forest, wetlanded watercourse for amphibia and reptiles crossing. However, the plan of filtration plant was destroyed wetland(sound ecosystem), natural forest, asian toad spawning area. According to the result of it schemed to build alternative wetland and spawning area, plan to healthy ecosystem and surface soil transplantation as compensation plan. The alternative wetland and spawning area are not only created a various water levels like depth of water is $0{\sim}30cm,\;30{\sim}60cm$, more than 1.5m but also it leads to asian toad spawning and wildlife inhabitant. Moreover, the ecosystem and surface soil transplantation be applied to use the Quercus acutissima forest resources(114 upper trees, 71 canopy trees, 401 shrubs) and surface soil$(5,072m^3)$ in ecology creation sets.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.4
• /
• pp.339-344
• /
• 2000

Utilization of animal excreta in aquaculture can have potentials of high fish production and low maintenance costs for fish farming and it can reduce water pollution caused by animal waste disposal. Integration of wastewater treatment pond system with aquaculture has been utilized in many countries. Ecologically balanced pond ecosystem is formed through the stabilization of wastes, the growth of aquatic plants, and the cultivation of fish. The most appropriate fish for rearing in these ponds are those which can feed directly on phytoplankton, especially algae. Carp were introduced into a tertiary pond - water depth of 2.2 m, water surface area of $130\;m^2$, volume of $148\;m^3$ - of a pond system treating milk cow excreta. The carp production was $125g{\cdot}m^{-2}year^{-1}$ which falls into upper range of $18\;-\;137g{\cdot}m^{-2}year^{-1}$ of treated sewage-fed carp farming of other countries. Average $BOD_5$ and T-N of the pond was 19.8 and $21.0\;mg{\cdot}L^{-1}$ respectively, and the ecological environment of it was suitable for growth of carp. Several carp of 100g were introduced in August into a secondary pond of the treatment system, whose average $BOD_5$ and T-N was 27.9 and $30.8\;mg{\cdot}L^{-1}$ respectively. They were died within one week, which may be attributed to the depletion of dissolved oxygen at dawn. Effluents from primary treatment can be used in fish pond with dilution and those from secondary treatment can be directly funnelled into it. Waste stabilization pond treating animal excreta can be utilized for fish rearing when its water quality maintains secondary treatment level.

• Journal of Wetlands Research
• /
• v.23 no.2
• /
• pp.189-200
• /
• 2021

To improve the water quality of agricultural reservoirs, constructed wetlands are applied in many places. These are technologies that establish ecosystems and important design factors include water depth distribution, inflow and outflow, water flow distribution, hydraulic residence time, water quality treatment efficiency, aspect ratio, and the distribution of open water and covered water surfaces. For high efficiency during the operation of a constructed wetland, the design needs to be optimized and this requires consideration of the different types and length of the intake dam as well as the type and connection of wetland cells. Therefore, this study was conducted to investigate and suggest factors that needs to be considered during the design and for efficient operation measures through field surveys of 23 constructed wetlands that have been established and operated in agricultural reservoirs. Results of the field investigation shows that several sites were being operated improperly due to the malfunctioning or failure of the water level sensors, sedimentation in the intake dam, and clogging of the mechanical sluice frames. In addition, it was found that as the length of the inlet channel increases, the ecological disconnection between the intake dam upstream and the wetland outlet downstream also increases and was identified as a problem. Most of the wetlands are composed of 2 to 5 cells which can result to poor hydraulic efficiency and difficulty in management if they are too large. Moreover, it was found that the flow through a small wetland can be inadequate when there are too many cells due to excessive amounts of headloss.

• Journal of Bio-Environment Control
• /
• v.30 no.1
• /
• pp.72-76
• /
• 2021

The amount of evapotranspiration (water absorption) according to wind speed showed the same trend in gold mound (Spiraea × bumalda), Japanese spurge (Pachysandra terminalis), and ivy (Hedera japonica Tobler). All the three plants showed maximum water absorption at 4 m·s-1; water absorption tended to decrease as wind speed decreased. The control group without wind speed treatment had the most amount of water absorption compared with the groups that were subjected to wind exposure. However, the plant growth of all three plants increased to the maximum value when wind speeds were 2 and 1 m·s-1. When comparing the relationship among water absorption, air temperature, and relative humidity, the water absorption of plants tended to be low from May 20 to 26, when air temperature and relative humidity were the lowest. The results of this study will help establish an urban wall-planting system taking building wind into consideration. Further, this study may help in the selection of plant types for ecological parks in windy islands.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.2
• /
• pp.171-176
• /
• 2000

A wastewater treatment pond system was developed for treatment and recycling of dairy cattle excreta of $5\;m^1$ per day. The wastes were diluted by the water used for clearing stalls. The system was composed of three ponds in series. A submerged gas collector for the recovery of methane was installed at the bottom of secondary pond with water depth of 2.4m. This paper deals mainly with performance of methane fermentation of secondary pond which is faclutative one. The average $BOD_5$, SS, TN, and TP concentrations of influent into secondary pond were 49.1, 53.4, 48.6, and 5.3 mg/l, and those of effluent from it were 27.9, 45.7, 30.8, 3.2 mg/l respectively. Methane fermentation of 2.4-meter-deep secondary pond bottom was well established at $16^{\circ}C$ and gas garnered from the collector at that temperature was 80% methane. Literature on methane fermentation of wastewater treatment ponds shows that methane bacteria grow well around $24^{\circ}C$, the rate of daily accumulation and decomposition of sludge is approximately equal at $19^{\circ}C$, and activities of methanogenic bacteria are ceased below $14^{\circ}C$. The good methane fermentation of the pond bottom around $16^{\circ}C$, about $3^{\circ}C$ lower than $19^{\circ}C$, results from temperature stability, anaerobic condition, and neutral pH of the bottom sludge layer. It is recommended that the depth of pond water could be 2.4m. Gas from the collector during active methane fermentation was almost 83% methane, less than 17% nitrogen. Carbon dioxide was less than 1% of the gas, which indicates that carbon dioxide produced in bottom sludges was dissolved in the overlaying water column. Thus a purified methane can be collected and used as energy source. Sludge accumulation on the pond bottom for a nine month period was 1.3cm and annual sludge depth can be estimated to be 1.7cm. Design of additional pond depth of 0.3m can lead to 15 - 20 year sludge removal.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.41 no.1
• /
• pp.82-92
• /
• 2013

This paper presents a landscape design proposal for the Kyeongsang National University Hospital in Changwon, Kyeongsangnam-do. The site is located at 555 Samjeongja-dong, Seongsan-gu, Changwon, Kyeongsangnam-do, and its area is approximately $79,743.1m^2$. The goal of the design was to create a landscape that helps the patients' recovery and public well-being as well as respects the surrounding environment. In order to achieve this goal, three design subjects were considered: maximizing the healing functions of the landscape, promoting ecologically regenerative landscape, and increasing the aesthetic value of the landscape based on the local context. For the healing aspect, first, therapeutic plants were carefully selected and various healing programs were introduced to the open space area such as the sensory garden, meditative space, the medicinal herb garden, outdoor acupressure treatment facilities, remedial playground etc. In addition, as the importance of patient's privacy is emphasized in research, the space and circulation patterns were divided according to the characteristics of the users. For ecological consideration, the design proposed to preserve and extend the existing ridgeline with pine forest, and recover the natural water system and recycle the water for the landscape management. For the aesthetic experience of the people, in contrast to the surrounding evergreen forest, diverse deciduous and flowering plants were introduced to arouse a sense of the season, and fruit bearing trees for wildlife to create a specific mood of being in nature so that people can listen to the songs of the birds and watch squirrels play etc. In addition, all the spaces and facilities were designed and placed according to universal design principles so that there would be no barrier for the patients to use them. Also, a sustainable management scheme was suggested to maintain the landscape in ecological and economical ways.

• Korean Journal of Environmental Agriculture
• /
• v.18 no.2
• /
• pp.191-195
• /
• 1999

An integrated wastewater treatment pond system is developed for treatment and recycling of excreta from dairy cattle. It is composed of three ponds in series. A pit with a capacity of $10m^3$, 2-day hydraulic residence time, and overflow velocity of $1.5m^3m^{-2}day^{-1}$ is located internally in primary pond. It is designed for efficient sludge sedimentation and effective methane fermentation. It receives $5m^3/day$ of diluted cattle excreta by the water used for clearing stalls. A submerged gays collector for the recovery of methane is installed on the top of the pit. The average BOD_5 concentration of influent is 398.7mg/l. That of the effluent from primary pond is 49.2mg/l. About 88% of BOD_5 are removed in primary pond. It is assumed that about 60% of the influent BOD_5 is removed in the pit and that almost all of the carbon of the removed BOD_5 in the pit is converted to methane and carbon dioxide. Methane fermentation of the pit is well established at $16^{\circ}C$. This phenomena results from temperature stability, complete anaerobic condition, and neutral pH of the pit. Gas from the collector is almost 90% methane, less than 9% nitrogen, and less than 1% carbon dioxide. Thus a purified methane is produced, which can be used as energy source.

• Korean Journal of Environmental Biology
• /
• v.41 no.2
• /
• pp.109-125
• /
• 2023

This study was conducted to select target fish species as baseline research for accumulation analysis of major hazardous chemicals entering the aquatic ecosystem in Korea and to analyze the impact on fish community. The test bed was selected from a sewage treatment plant, which could directly confirm the impact of the inflow of harmful chemicals, and the Geum River estuary where harmful chemicals introduced into the water system were concentrated. A multivariable metric model was developed to select target candidate fish species for hazardous chemical analysis. Details consisted of seven metrics: (1) commercially useful metric, (2) top-carnivorous species metric, (3) pollution fish indicator metric, (4) tolerance fish metric, (5) common abundant metric, (6) sampling availability (collectability) metric, and (7) widely distributed fish metric. Based on seven metric models for candidate fish species, eight species were selected as target candidates. The co-occurring dominant fish with target candidates was tolerant (50%), indicating that the highest abundance of tolerant species could be used as a water pollution indicator. A multi-metric fish-based model analysis for aquatic ecosystem health evaluation showed that the ecosystem health was diagnosed as "bad conditions". Physicochemical water quality variables also influenced fish feeding and tolerance guild in the testbed. Eight water quality parameters appeared high at the T1 site, indicating a large impact of discharging water from the sewage treatment plant. T2 site showed massive algal bloom, with chlorophyll concentration about 15 times higher compared to the reference site.

• The Korean Journal of Ecology
• /
• v.27 no.6 s.122
• /
• pp.375-381
• /
• 2004

We investigate the biological treatment of processed-leachate from SUDOKWON landfill site in Korea by the reed (Phragmites australis)-bed with a continuous flow system. The reed individuals showing superior growth in processed-leachate experiment were selected among the reeds of thirteen natural habitats by means of the comparisons between the removal rates of nutrient salts, eco-physiological responses and growth. The reed-beds (combination of the reed individuals showing superior growth with helper microorganisms) were continuously supplied with processed-leachate. We monitored the effluents that passing through the reed-beds during the experiment period. After five weeks, analysis results of effluent from each reed-bed were as follows; chromaticity, total nitrogen, total phosphorus, biological oxygen demand, chemical oxygen demand, total dissolved solid and salinity decreased $29.5{\sim}36.9\%,\;49.4{\sim}67.2\%,\;42.1{\sim}94.6\%,\;74.5{\sim}88.8\%,\;15.6{\sim}20.8\%,\;17.5{\sim}35.4\%\;and\;15.3{\sim}34.7\%$, respectively. These results represented the substantial improvement of water-quality after passing through reed-bed in a continuous flow system.