• Journal of Soil and Groundwater Environment
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• v.17 no.4
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• pp.27-35
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• 2012

Recently, there has been increasing interest in the use of rain garden systems as environmentally friendly ecological infrastructures for controlling stormwater runoff and managing non-point source pollution and information for the contamination of soil and plants can be essential for sustainable rain garden management. In this study, four rain garden mesocosms, namely single species planting with Rhododendron lateritium, single species planting with Zoysia japonica, mixed planting with R. lateritium and Z. japonica, and control without plants, were tested to investigate the change in concentrations of nutrients (N and P) and heavy metals (Cd, Cu, Pb, and Ni) in the soil and plants used in the rain garden system. The presence of plants resulted in greater nutrient retention in soil and lower potential leaching from the system. All systems showed an increase in the heavy metal concentrations in soil. The concentrations of most heavy metals were found to be higher in the herbaceous plants (Z. japonica) than in the shrubs (R. lateritium). The belowground part (root) had higher heavy metal concentrations than the aboveground part (leaf) but also showed a potential increase in leaves, and hence, careful plant management should be considered during rain garden operation.

• Journal of Forest and Environmental Science
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• v.31 no.2
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• pp.109-118
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• 2015

Allelopathy is an ecological phenomenon that refers to the beneficial or harmful effects of one plant on another plant, both crop and weed species, by the release of organic chemicals (allelochemicals) from plant parts by leaching, root exudation, volatilization, residue decomposition in soil and other processes in both natural and agricultural systems. Allelopathy can affect many aspects of plant ecology including occurrence, growth, plant succession, the structure of plant communities, survival, dominance, diversity, and plant productivity. In this review, we describe the concept of allelopathy, some mechanisms of operation within plants and then focus on a select number of gymnospermous tree genera: Ephedra, Pinus, Taxus, Cedrus, Juniperus, Picea, Cunninghamia and Araucaria. Pinus, Taxus (yew) and Cedrus (cedar) trees have a strong negative allelopathic effect on the germination, growth, or development of other plant species in the forest community.

• Membrane and Water Treatment
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• v.7 no.6
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• pp.555-571
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• 2016

Heavy metal contamination has attracted considerable attention during recent decades due to the potential risk brought about for human beings and the environment. Several adsorbent materials are utilized for the purification of contaminated water resources among which chitosan is considered as an appropriate alternative. Copper is a heavy metal contaminants found in several industrial wastewaters and its adsorption on porous and macroporous chitosan membranes is investigated in this study. Membranes are prepared by phase inversion and particulate leaching method and their morphology is characterized using SEM analysis. Batch adsorption experiments are performed and it is found that copper adsorption on macroporous chitosan membrane is higher than porous membrane. The iso-steric heat of adsorption was determined by analyzing the variations of temperature to investigate its effect on adsorption characteristics of macroporous chitosan membranes. Furthermore, desorption experiments were studied using NaCl and EDTA as eluants. The mechanism of copper adsorption was also investigated using XPS spectroscopy which confirms simultaneous occurrence of chelation and electrostatic adsorption mechanisms.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.111-114
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• 2006

The effects of indigenous bacteria on geochemical behavior of As in As-contaminated sediments (Hwachon mine and Myoungbong mine) after biostimulation with a variety of carbon sources were investigated under anaerobic condition. In Hwachon sediment, As was dramatically extracted from nonsterile sediment with time, reaching the highest concentration of $500{\mu}g/L$. The As leaching was likely caused by microbial dissolution of Fe oxides/oxyhydroxides with which As had been coprecipitated. However, in the case of Myoungbong sediment supplied with glucose, dissolved As decreased with time likely due to production of As sulfide(s) and subsequent precipitation, which resulted from bacterial reduction of $SO_4^{2-}$. The results implied that bacterial in-situ stabilization of As In subsurface has a potential to be practically applied.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.477-480
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• 2005

The discharge of sewage sludge is rapidly increasing in Korea. But the most common sewage sludge disposal alternative is to incinerate and to deposit it in controlled landfills. However, space limitations on existing landfill sites, and increasing environmental concerns have prompted the investigation of alternative ash disposal routes. The utilization of sewage sludge ash would contribute to the elimination of an environmental problem and to the development of new high-performance materials. The purpose of this study is to apply to Alkali Activation into solidification of sewage sludge ash. It achieves leaching test, chemical composition and compressive strength test. As a result of tests, the sewage sludge ash has sufficient potential for use of pozzolanic raw material. However, it is judge to be available to construction material if research is continuously gone.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.739-742
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• 2002

Immobilization of contaminants in contaminated soils by solidification processes is an attractive potential remediation process. In this study, the treatability of lead, copper, toluene, and COD was investigated by leaching test. Industrial sand was adopted as the test material and was contaminated with lead copper, and toluene to 100mg/kg, 500mg/kg, 200mg/kg respectively. P solidifying agent was used as the binder(20% by weight of contaminated soil) in the solidification treatment. The leachability of contaminants leached from the solidified soil was evaluated using column test. The percentage of contaminants leached from the solidified soil was significantly reduced by reaction of waste species with cement components and encapsulation reaction of binder. Based on the tests, it is ascertained solidification process can be a very effective method to control the elution of contaminants from the contaminated soil.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.687-690
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• 2004

The discharge of sewage sludge ash that is rapidly increasing in Korea. The utilization of sewage sludge ash would contribute to the elimination of an environmental problem and to the development of new high-performance materials. So the paper is focused on an experimental study in order to investigate the utilization of sewage sludge ash as the construction materials. It achieves leaching test, chemical composition and compressive strength test. As a result of tests, the sewage sludge ash has sufficient potential for use of pozzolanic raw material. However. it is judged to be available to construction material if research is continuously gone.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.19-25
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• 2000

The adsorption and leaching of organophosphorus pesticide, EPN (O-ethyl-O-4 -nitrophenyl phenyl phosphonothioate) were investigated in Namwon soil(black volcanic soil), Aewol soil(very dark brown volcanic soil) and Mureung soil(dark brown nonvolcanic soil) in Cheju Island. The residue of EPN was surveyed on coastal environment of Cheju in Aug. 1996. The organic matter of Namwon soil, Aewol soil and Mureung soil was 19.8, 6.2 and 2.4%, respectively. The cation exchange capacity of Namwon soil, Aewol soil and Mureung soil was 24.8, 13.0 and 9.5 meq/100 g, respectively. The Freundlich constant, k value, was 89.4, 26.9 and 9.25 for Namwon soil, Aewol soil and Mureung soil, respectively. The k value of Namwon soil with very high organic matter content and cation exchange capacity was the highest for Aewol soil and Mureung soil. The Freundlich constant, 1/n, show a high correlation with organic matter content, i.e. it is less than unity for organic matter rich soil of Namwon soil and greater than unity for organic matter poor soil of Mureung soil. The leaching of EPN was slower for Namwon soil with high k values, and faster for Mureung soil with low k values. The results of the study was demonstrated the potential of pollution for EPN have little leached into soil environment. EPN was not detected in seawater and sediment in the coastal environment in Cheju Island. EPN used in the farm on tile Cheju island were not residued in the coastal environment.

• Journal of Animal Environmental Science
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• v.1 no.2
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• pp.173-178
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• 1995

The aim of this study was to describe the NO$_3$ leaching in grassland ecosy-stems. Field study was performed in the southwestern district of Germany from 1991 to 1993. The study included 3 different slurry application, conventional slurry application, 50% reduced slurry application and without slurry application. On each plot were installed 3 ceramic cups at 120cm depth. Samples were collected twice a month and analysed for NO$_3$ colorimetrically using a Tecator Auto-Analyzer. Percolation was calculated as the difference between precipitation and potential evapotranspiration. The NO$_3$ concentration in soil water was remarkably variable during the year. The average NO$_3$ concentration during the experiment was the lowest (8.5mg/l) without slurry application and the highest with 240kg N/ha cattle slurry (25.3mg/l). the NO$_3$-N leached per year were respectively 29, 23, and 12kg/ha in case of 240, 120 and 0kg N/ha when cattle slurry was applied. The conventional feeding density of cattle husbandry in the district caused the NO$_3$ contamination in ground water. When the amount of cattle slurry applied was reduced to 50%, the NO$_3$ loading in ground water was reduced greatly. Therefore, the reduction policy of cattle slurry can positively contribute to the prevention of the NO$_3$-contamination in groundwater.

• Journal of Wetlands Research
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• v.22 no.3
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• pp.171-177
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• 2020

To improve the nitrogen reduction capability of stormwater treatment systems subjected to intermittent saturation, organic materials are often added as filter media. However, these materials can be an additional source of organic carbon and increase the chemical oxygen demand (COD) in the outflow. In this study, different types of organic filter media were subjected to a batch leaching test to observe and quantify the release of COD. Results reveal that the initial pH of the tap water used for soaking which is 7.5-7.7 is conducive to the release of organics from the media to the leachate. The highest amount of COD released was observed in yard clippings and woodchip followed by compost and bark mulch. The leaching of organics also increased as the size of the media decreases due to higher surface area per volume. In addition, empirical regression analysis predicted that COD from these organic media will be exhausted from the material in 3-5 months to up to 26 months depending on the type of media. The results of this study can serve as a guide in estimating the potential release of COD in organic media in order to ensure their safe application in stormwater treatment facilities.