• Korean Journal of Organic Agriculture
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• v.20 no.1
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• pp.37-48
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• 2012

This study was conducted to evaluate the effects of ground cover treatments on the nutrient contribution in a 'Niitaka' pear ($Pyrus$ $pyriforia$) orchard. Treatments included; 1) sod culture, 2) winter cover crop [ryegrass+hairy vetch], and 3) winter [ryegrass+hairy vetch]+summer [greensolgo (sudan grass ($Sorghum$ $bicolor$ L.))+ nemajanghwang (crotalaria ($Crotalaria$ $juncea$ L.)] cover crops. Ryegrass and hairyvetch were seeded with 6.4 kg/10a and 3.0 kg/10a, respectively, on October 17 of 2008, and greensolgo and nemajanghwang were seeded with 2.0 kg/10a and 3.0 kg/10a, respectively, on June 4 of 2009 at a diligent farmer in Boseong in Chonnam. Winter+summer cover crops provided greater amounts of dry weight, followed by winter cover crop and sod culture. The difference of amounts of dry weight from the ground covers affected to the levels of total N, P, and K contents, which were greater nutrient levels than those of recommended nutrient requirement for satisfying 10- to 12-year-old pear tree growth. Greater amounts of dry weight from the ground covers increased organic matter and concentrations of K and Mg in soil. Foliar nutrient concentrations, as an indicator of nutrient status of a tree, were not affected by application of ground cover treatments.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.1
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• pp.1-16
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• 2020

The APEX model has been developed for assessing agricultural management efforts and their effects on soil and water at the field scale as well as more complex multi-subarea landscapes, whole farms, and watersheds. Recently, a key component of APEX application, named APEX-Paddy, has been modified for simulating water quality by considering paddy rice management practices. In this study, the performance of the APEX-Paddy model was evaluated using field data at Iksan experimental paddy sites in Korea. The discharge and pollutant load data during 2013 and 2014 were used to both manually and automatically calibrate the model. The APEX auto-calibration tool (APEX-CUTE 4.1) was used for model calibration and sensitivity analysis. Results indicate that APEX-Paddy reasonably performs in predicting runoff discharge rate and nitrogen yield. However, sediment and phosphorus yield is not correctly predicted due to the limitation of model schemes. With APEX-Paddy, the performance in reproducing the discharge and nitrogen yield is found to be a satisfactory level after manual calibration. The manually calibrated model performed better than the automatically calibrated model in nearly all comparisons. For runoff, manual calibration reduced PBIAS while R² and NSE values of the automatically calibrated model were the same as the manual calibration. For T-N, NSE and PBIAS were reduced when using manual calibration, whereas R² value was the same as manual calibration. The limitation of the APEX-Paddy model for predicting sediment, as well as the phosphorous yield, was discussed in this study.

• Journal of the Korean association of regional geographers
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• v.9 no.3
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• pp.276-296
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• 2003

This study is to analyze the adoption of environmentally friendly fanning(EFF) by Actor-Network Theory(ANT). ANT declares that the world is full of hybrid entities containing both human and non-human elements and maintains that adoption of an innovation comes as a consequence of the action of everyone in the chain of actors who has anything to do with it. In this study, adoption of EFF will be analysed through the role of actors and networks. And this paper try to identify the intermediaries and obligatory passage point(OPP) in each networks. In study area, 5 actors, -nature, governmental institute, food processors, consumers and farmers-, have each roles in their networks, But only 18 farmers adopted EFF. This study revealed that three OPPs were not overcome in each network. The one is nature, such as water and soil pollution. Another is shortage of reliability between farmers and governmental institute. The other is shortage of information about agricultural commodity trade. And through this application of ANT to the EFF, we contend that ANT can be useful for studies of diffusion of EFF and sustainability of rural systems in situations where interactions of the social, technological and political are regarded as particularly important.

• Journal of Crop Science and Biotechnology
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• v.10 no.1
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• pp.50-56
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• 2007

Barley S-adenosylmethionine synthetase1 gene, which was differentially expressed in seed development of extra early barley, was regulated by the phytohormones and abiotic stresses. In order to identify the regulation regions which were involved in transcriptional control of the phytohormones and abiotic stresses, we isolated 1459 bp fragment of HvSAMS1 gene promoter using genome walking strategy and deletion series were constructed. Deleted upstream fragments(-1459, -1223, -999, -766, -545, -301 bp) were fused to the GUS reporter gene and evaluated via Agrobacterium-mediated transient expression assay. Increased GUS activity of HvSMAS1 promoter -301/GUS construct under each of NaCl, $GA_3$, ABA and ethylene application was found. However, GUS activity was negligible in the leaves transformed with the HvSMAS1 promoter(-1459, -1223, -999, -766 and -545)/GUS constructs. No significant induction of GUS activity was observed for the ethionine and spermidine treatments. In order to locate promoter sequence of the HvSAMS1 gene that was critical for the activation of gene expression, deletion and addition promoter derivatives(+, includes 43 bp of 5' ORF) of the HvSAMS1 gene fused to the GUS reporter gene were applied. The tobacco leaves which harbored the additional HvSAMS1 promoter(-1459+, -1459 to -546, -545+ and -301+)/GUS construct did not significantly induce GUS activity as compared to the HvSAMS1 promoter(-1459, -545 and -301)/GUS constructs under each of NaCl, ABA and $GA_3$ treatment. However, the GUS activity was high in the tobacco leaves which harboring the -211 to -141 regions of the HvSAMS1 promoter. This result suggested that HvSAMS1 gene expression might be regulated by this region(from -211 to -141).

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.563-573
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• 2017

Coal ash is generated from coal-fired thermal power plants every year. The remaining quantity of coal ash ends up in the landfills except for the recycled portion, and the existing ash pond capacity is limited almost. Currently, the difficulties are faced in building a new ash treatment plant because of the concerns about the environmental impacts of landfills at individual plant facilities. In terms of minimizing the environmental impact, the recycling and effective uses of coal ash are recognized as urgent issues to be challenged. Accordingly, this study examines the obstacles in expanding the recycling of the coal ash in South Korea and proposes solutions based on the case study analysis. The analysis results are as follows: 1) specific recycling guidelines and standards are required to be established in accordance with the contact medium (soil, ground water, surface water and sea water) and the chemical. 2) by providing the recognition environmentally safe in recycling the coal ash, transparency in establishing the planning stages and active communication with the community through promotion and research are essentially needed. 3) practical support system is required to encourage the power plant companies to use the coal ash as beneficial use.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.478-487
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• 2013

Onions were treated with different amounts of sulfur (S) during cultivation and examined for their physicochemical properties and flavor. Onions cultivated without S application were the control group; the treatment groups were grown in soil that had been pretreated with S and received additional S applications or four times before harvest. As the number of S applications increased, the levels of crude protein, quantified with total nitrogen; ash, approximating total amounts of minerals; and dietary fiber of the onions tended to increase. The mineral compositions also improved, with noticeable increases in the levels of Mg, K, Fe, and Zn. In particular, the reducing capacity of the onions increased appreciably (p<0.05), without increases in the levels of S-containing compounds such as thiosulfinate or S-containing amino acids. Nevertheless, the spicy hot taste and flavor, which is generated mainly from S-containing compounds, were perceived more strongly in the onions that had received more S applications.

• Journal of Korean Society for Geospatial Information Science
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• v.16 no.1
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• pp.23-32
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• 2008

According to recent frequent local flash flood due to climate change, the very short-term rainfall forecast using remotely sensed rainfall like radar is necessary to establish. This research is to evaluate the feasibility of GIS-based distributed model coupled with radar rainfall, which can express temporal and spatial distribution, for multipurpose dam operation during flood season. $Vflo^{TM}$ model was used as physically based distributed hydrologic model. The study area was Yongdam dam basin ($930\;km^2$) and the 3 storm events of local convective rainfall in August 2005, and the typhoon.Ewiniar.and.Bilis.collected from Jindo radar was adopted for runoff simulation. Distributed rainfall consistent with hydrologic model grid resolution was generated by using K-RainVieux, pre-processor program for radar rainfall. The local bias correction for original radar rainfall shows reasonable results of which the percent error from the gauge observation is less than 2% and the bias value is $0.886{\sim}0.908$. The parameters for the $Vflo^{TM}$ were estimated from basic GIS data such as DEM, land cover and soil map. As a result of the 3 events of multiple peak hydrographs, the bias of total accumulated runoff and peak flow is less than 20%, which can provide a reasonable base for building operational real-time short-term rainfall-runoff forecast system.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.219-229
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• 1993

Effects of paper mill sludge-fertilizers were investigated on the growth performances of tree seedlings under field conditions. Two types of sludge-fertilizers applied were an organic sludge compost and a processed sludge-pellet fertilizer strengthened with several components of organic and inorganic nutrients. Three species of tree seedlings studied were ibota privet(Ligustrum obtusifolium) and yellow poplar(Liriodendron tulipifera) of 1-0 year seedlings and also eastern white pine(Pinus strobus) of 2-2 year seedlings. Nitrogen and phosphorus contents of plot soil treated with sludge compost+sludge-pellet fertilizer+sludge-pellet fertilizer plot were increased to 8 times and 2.6 times as those of control plot, respectively. The growth performances of root collar diameter and seedling height were repeatedly measured up to five times through the growing season and the results were analyzed statistically by analysis of variance of randomized block design and Duncan's multiple range test. The growth performances of dry weight were measured after last fifth measurements.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.6
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• pp.130-138
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• 2007

To protect the surface of ground-cutting slopes occurring at the national road substitute detour [roundabout road]construction jobsite between Munduk and Wubokgu within the jurisdiction of Pohang-si and environment-friendly road construction, a test execution of re-vegetation measures on the major slopes was done and the results are as follows : As a result of finding out the number of sprouting individuals on the test construction site, the average number of sprouting individuals on the three test spots by the method of revegetation measures D, revegetation measures A, and revegetation measures B was 1,292 number of per square meter, 1,190 number of per square meter, and 1,095 number of per square meter respectively, which statistics were higher than those of test spot by the revegetation measures C. As a result of finding out living plant's breeding index [weight in dried state], the average dried weight of living plant at the test spot by the method of revegetation measures B, in case of foreign herbal species, was the highest marking 8.96 grams per square meter, and the next was 6.86grams per square meter by the method of revegetation measures D, and the next after was 6.80 grams per square meter by the method of revegetation measures A, and the last 5.93 grams per square meter by the method of revegetation measures C. As a result of finding out the covering degree on the slopes, the same average covering degree of 80% and 77.5% in revegetation measures A and revegetation measures D individually, which showed a somewhat higher covering degree than those of revegetation measures B and revegetation measures C. As a result of finding out appearing plants on the test construction site, seeding plant life was found to be sprouting on all test spot while native and foreign herbal species and herbaceous plant as well as shrubs were growing in good harmony with each other. However, in case of revegetation measures B and revegetation measures C method, foreign plant species are dominantly growing. As a result of inspecting rifts on the slopes and the excavated state by water, there existed cracks in some of base materials only in revegetation measures C method applied spot.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.257-266
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• 2002

The purpose of this study is screening of microfloras involved in hydrolysis of seaweed tenella, seaweed fusiforme and green laver. This is a part of studies on the hydrolysis of seaweed using microorganisms. First, about two hundred microflora samples were obtained from mountain, rice field, dry field, sea, seaside and fish market in the vicinity of Yeosu. Thirty-three microflora samples were screened from the destruction of tissue in sea tangle and sea mustard. It was sufficient that results of the naked eye observation were obtained at eight microflora samples as a feces of bull, a decayed pine tree, a soil of dry field, the mud of the banks in a rice field, the water of a ditch in a rice field, the weed of the banks in a rice field, the water in a rice field and leaved in the air. Above all, extraction rate and contents of reducing sugar in extracts of seaweeds added a decayed pine tree(sample No. 8) and the water of a ditch in a rice field(sample No. 27) were showed high value. And the value of chemical analysis of the sample is much better in comparison with control. Accordingly the hydrolysis of seaweed using microorganisms in the inside of these microflora samples can be possible.