• Journal of Environmental Science International
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• v.21 no.8
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• pp.931-938
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• 2012

The effects were investigated of different lengths and numbers of slitwalls in drainless containers on growth and change in soil moisture volumes on the growth of Diffenbachia amoena 'Marianne' and Begonia rex. Drainless containers filled with amended soil, with square shape ($240mm{\times}240mm$) were used, as well as three different sets of slitwalls (2, 4 or 8, respectively) in addition to non-slitwall containers. Two indoor foliage plants were grown in slitwall containers in randomized blocks with 3 replications in greenhouse conditions, from March to September, 2009. Soil moisture volumes per container were measured by weighing containers every 2 hours during the day. The change in soil moisture volumes showed considerable differences among slitwalls tested in comparison to control containers before and after twice-weekly irrigation. Particularly, the differences in the S2 (195mm, slitwall 2) containers were significantly greater than other containers tested. For Diffenbachia amoena 'Marianne', plant height, length of leaf, dry weight and fresh weight were higher with S2 containers than with those grown in other containers tested. The Begonia rex with the best quality in terms of plant height, length of leaf and width of leaf was grown in S8 (360mm, slitwall 8) containers. Particularly, statistical analysis has indicated that shoot fresh weights of Begonia rex grown in S8 were 3-fold higher than those grown in CS8 containers. The different results obtained within the two species led us to hypothesize a species-specific influence on indoor foliage plant performance. However, plants of both species grown in slitwall containers showed good results compared with plants grown in non-slitwall containers.

• Journal of Environmental Science International
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• v.22 no.2
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• pp.251-257
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• 2013

Discharge data examine the process of hydrologic cycle and used significantly in water resource planning and irrigation and flood control planning. It makes high quality discharge data, they carry out research on standard and method of discharge measurement, and equipment improvement. Now various flow meters are utilized to make discharge data in Korea. However, accuracy of equipment and exprerimental research data from measurement are not enough. ADCP(Acoustic Doppler Current Profiler) have been introduced and utilized for flow measurements since the end of 1980's. ADCP flow method is a formal method for flow measurement can easily applyd to relatively large rivers gradually recognized. This equipment can measure the non-contact three-dimensional velocity and water depth data very quickly and efficiently. Also, spatial and temporal resolution of the data is more accurate than any other flow measurement methods which measure flow rate by velocity - area measurement method. In this paper, the velocity is measured using various flow meter and verified the effectiveness by applying from the ADCP in Geum-river. Various flow meters which are med for discharge measurements are VALEPORT002, FLOW TRACKER, PRICE AA and ADCP. The average of five times flow measurement result by ADCP was $10.412m^3/s$, with a standard deviation of 0.68. The repeat test by ADCP and comparison between ADCP and other flow devices to verify the most import factor, flow measurement accuracy. In the result, repeat test of the ADCP showed similar values, flow values were similar to other velocity device results and the average error is 7.7%.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.2
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• pp.201-208
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• 2012

Wangsong Reservoir needs a systematic approach that can control water purity and water quality improvement. This study was carried out to assess the seasonal variation of water quality and the effect of pollutant being loaded from watershed in a sallow eutrophic reservoir(Wangsong Reservoir) from March to November, 2011. Wangsong Reservoir, located in Uiwang City, has the capacity of 2 million $m^{3}$ in irrigation water supply with the drainage of 4.2 $km^{2}$. Average concentrations of BOD, COD, T-N, T-P, and Chloropyll-a in Wangsong Reservoir were 5.8 mg/L, 9.7 mg/L, 4.299 mg/L, 0.106 mg/L and 73.1 mg/$m^{3}$, respectively. In the inflow streams and treated sewage of Wangsong Reservoir, the T-N concentrations of 4.114 - 14.619 mg/L were higher than those in the Reservoir and the other pollutants were lower. As a result of investigation, Wangsong Reservoir exceeded the agricultural water standard level due to algal growth and accumulation from the upper streams and sewage. In order to achieve the targeted water quality in Wangsong Reservoir, it is required to be decreased in pollutants of internal and inflow streams.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.458-462
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• 2013

A drainage ditch is normally a component of drainage networks in farming systems to remove surplus water, but at the same time, it may act as a major conduit of agricultural nonpoint source pollutions such as sediment, nitrogen, phosphorus, and so on. The hybrid turbidity reduction system using biodegradable check dam and synthetic polymer was developed in this study to manage pollutant discharge from agricultural farmlands during rainfall events and/or irrigation periods. The performance of this hybrid system was assessed using a laboratory open channel sized in 10m-length and 0.2m-width. Various check dams using agricultural byproducts (e.g., rice straw, rice husks, coconut fiber and a mixture of rice husks and coconut fiber) were tested and additional physical factors (e.g., channel slope, flowrate, PAM dosage, turbidity level, etc.) affecting on turbidity reduction were applied to assess their performance. A series of lab experiments clearly showed that the hybrid turbidity reduction system could play a significant role as a supplementary of Best Management Practice (BMP). Moreover, the findings of this study could facilitate to develop an advanced BMP for minimizing nonpoint source pollution from agricultural farmlands and ultimately to achieve the sustainable agriculture.

• Journal of Korean Academy of Nursing
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• v.42 no.6
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• pp.791-798
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• 2012

Purpose: The purpose of this study was to analyze the effectiveness of saline solution vs. heparinized-saline for maintenance of arterial lines and to detect changes in platelet and aPTT as physiological indexes. Methods: In this nonequivalent control group, non-synchronized, double-blind study the effects of heparinized and saline solution on the maintenance of arterial lines were compared. Fifty five patients received the heparinized solution and fifty nine patients received the saline solution. All patients who had surgery in K-university hospital between September and December 2011 were eligible for participation in the study. Results: There was no statistically significant difference between the saline and the heparin group in the maintenance time of the arterial lines or the number of irrigations. There was no statistically significant difference between the groups in changes in the number of platelets and aPTT for interaction between the groups and time intervals. Conclusion: The results indicate that saline solution can be used as an irrigation solution for the maintenance of arterial lines of adult surgical patients, rather than heparinized-saline, in view of potential risk factors in the use of heparin.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.1028-1033
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• 2010

Wastewater reuse for agricultural irrigation needs treatment and control of pathogens to minimize risks to human health and the environment. In order to evaluate the water quality of UV-treated reclaimed water, this study focused on the relationship between micro-pathogens and particulate matters. MS2 was selected as an index organism because it has similar characteristics to human enteric virus and strong resistance to UV disinfection. The turbidity and suspended solid (SS) were selected for test parameters. In this study, it was performed with different UV doses (30 and $60mJ/cm^2$) for estimation of the MS2 inactivation rate using collimated beam batch experiments in the laboratory. The experiment results by turbidity or SS concentration presented that the increased concentration of them lowered MS2 inactivation. At the turbidity (below 4.27 NTU) and SS (below 1.47 mg/L) of the low level range, the inactivation of 60 UV dose is higher than 30 UV dose. However, at the turbidity and SS of the high level, the increasing UV dose did not show apparent increasing the MS2 inactivation. In quantitative microbial risk assessment (QMRA), it can confirm the trend that $P_D$ and turbidity concentrations have positive correlationship at the low concentration, which was also observed in SS. The QMRA can be helpful in communication with public for safe wastewater reuse and be recommended.

• Journal of Ecology and Environment
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• v.35 no.4
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• pp.343-349
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• 2012

The use of growth medium is often recommended milkweed seedlings to grow and develop after emergence, and it is affected by growth medium and local habitat conditions. The effects of growth medium and partial shade on early growth of milkweed under drought stress (Calotropis procera L.) were studied in a field experiment. A split-split plot experimental design with three replications was carried out in the nursery. The main treatment plot was divided into two levels of shade; (no shading and partial shading). Sub treatment plot1 included growth medium at four levels (G1 = clay [suitable for milkweed growth], G2 = clay + sand, G3 = clay + perlite, G4 = clay + perlite + sand) and sub treatment plot2 included drought (irrigation intervals) at six levels (D1 = 2 [control], D2 = 4, D3 = 6, D4 = 8, D5 = 10, and D6 = 12 days per for three month). The results showed that drought stress significantly decreased emergence percentage, shoot length, shoot dry weight (SDW1), root dry weight (RDW), seedling dry weight (SDW2) and vigor index (VI). The use of growth medium increased all seedling characteristics. The G3 (clay + perlite) growth medium showed the highest performance, especially in terms of emergence percentage and seedling dry weight. Partial shade improved shoot length, shoot dry weight, and vigor index. Our results showed that the best treatment for high-vigor milkweed seedlings under drought stress was G3 (clay + perlite) growth medium and partial shade.

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.11a
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• pp.28-45
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• 2000

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21-23C for 40 days after heading, increased with long anomalies in 1998-99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than normal in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Tonsil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than Japonica rices, photoperiod sensitive and thermo-sensitive ecotypes

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.06a
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• pp.137-159
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• 1999

Over the last three decades, Korean farming system has been directed to maximum agricultural production and to increase farmer's income through adoption of high-yielding crop varieties and high input of agrochemicals . These farming practices have resulted in problems of water-quality deterioration, soil degradation , and food safety. At present, over 40 million tones of animal waste are bing produced annually, which amounts to disposing the waste at the annual rate of 20 tones per ha in the total area of farming land in Korea. Nearly a half of total available water resources is used as irrigation water predominantly for rice paddy field. Thus, non-point source contamination of the water resources has been linked to agriculture across the nation. However, the extent to which agriculture contributes to the water quality is not fully known. Recently, Korean government provided various institutional measures to reduce the negative impacts of agricultural practices on the environ ental quality, and the Agricultural Environment Act was also passed by the legislature in 1998 and became effective January 1999. This Act does not cover the broad spectrum of the sustainable agriculture ; thus, the limited incentives within this Act are arguably ineffective to control the non-point source pollution. Recently new bulk blending of fertilizers(BB fertilizer) are bing produced (100, 000 tones in 1998) with Government subsidies. The BB fertilizers are to balance N-P-K ratio in the soils . Although the use of the BB fertilizers are encouraged with Government subsidies, non-point source pollution is still serious and will become worse. Precision farming is regarded as a new means for sustainable agriculture. It is a new technology that modifies the existing techniques and incorporates new one such as GIS, GPS , differential applicator to produce a new set of tools for the farmer to use. Precision farming, however, has constraints for individual farming practices. For exam le , farm size or parcel unit of each farmer is too small to adopt the precision agriculture on farmhouse-hold bases and farmer's ability to adopt the new technology is limited. However, it would be appropriate to establish local or regional cooperatives to operate such a precision farming system. It is recommended that Government provide sufficient incentives to help establish local and/or regional cooperatives.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.142-148
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• 2014

Effect of silicon (Si) nutrition on growth and temperature stress tolerance of Nephrolepis exaltata 'Corditas' grown in a soilless substrate was examined. In vitro-grown acclimatized plantlets were transplanted into the pots containing a coir-based substrate. A nutrient solution containing 0, 50, or $100mg{\cdot}L^{-1}$ Si was supplied through a drip-irrigation system. After 5 months of cultiv ation, S i-treated and -untreated p lants were grown at 10, 25, or $40{\pm}1^{\circ}C$ under a 12 h photoperiod with $530{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD and 60% RH. After 7 days, chlorophyll content and chlorophyll fluorescence parameters were measured. Silicon nutrition had a negative effect on growth characteristics of N. exaltata 'Corditas'. However, Si-treated plants had more tolerance to temperature stress than the control plants. The Fv/Fm value was not significantly different when the plants were exposed to $25^{\circ}C$. However, significant difference in Fv/Fm was recorded when plants were exposed to 10 or $40^{\circ}C$. Thus, Fv/Fm could be used as an indicator of low and high temperature tolerance in ferns. The present study also suggests that application of Si may be used to enhance temperature tolerance of ferns.