• Korean Journal of Weed Science
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• v.18 no.3
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• pp.262-267
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• 1998

We evaluated Ambrosia artemisiifolia var. elatior, Ambrosia trifida, Rumex crispus which were reported to have good phytoremediatibility in different concentrations of Cu and Cd. Different growth responses were found in different heavy metal concentrations. Good growth rate for A. trifida and A. artemisiifolia var. elatior in Cu and Cd treatments and poor growth for R. crispus in Cd treatment were found. Although growth was retared in all tested weeds up to 200ppm for Cu and 50ppm for Cd, the high amount of heavy metal uptake indicated that these weeds could be used as phytoremediation. The choice of proper plant for bioremediation in different sources of heavy metal pollution seems important. In this regard, A. trifida which showed little variation in Cu accumulation in shoot under different Cu concentrations could be used for phytoremediation and phytostabilization.

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.164-170
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• 2010

In organic agriculture, cover crops are used for weed control. Cover crops inhibited weed germination or growth by allelopathy or shading effects. In this study, we used rye as cover crop to control weed in organic soybean field. The main treatment was rye using method such as living mulch, incorporating and mowing. Sub-treatment was rye planting density and soybean planting density. One month after soybean sowing, weed emergency and growth had been highly suppressed by rye in all treatments. Living mulch treatment was the best effective way to control the weed about 92%, and mowing treatment was the second about 75% compare to control. The weed control efficiency between rye planting densities was similar during one month. Soybean planting density treatment was same result as rye planting density. As a result of this experiment, we recommend rye as living mulch in one row planting.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.52-57
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• 1987

To know the effects of weeding periods (weeding from 12 days, 28 days and 42 days after seeding to harvest, and weeding from seeding to 14 days, 28 days and 42 days after seeding) and growing conditions such as transparent polyethylene film mulch (P.E. mulch) and bare soil on growth and yield of peanuts, "Yeongho-Tangkong" was planted on May 10, 1984. Under P.E. mulch, the number of weeds was higher, but the weed dry weight was lower than in bare soil by the middle of July. Sixty days after seedings, the length of main stems in weedy check plots was longer, but shoot dry weight was lower compared to weed free plot. In the correlation coefficients between weed dry weight and the shoot dry weight of peanut on July 14, the growth retardation of peanuts due to weeds was showed earlier under P.E. mulch than in bare soil. Shoot dry weight, shelling ratio, number of seeds per pod, 100 pod weight, and seed yield were higher under P.E, mulch compared to bare soil. But weed dry weight, length of branches, number of pod bearing branches, number of pods per square meters, and pod yield were similar between P.E. mulch and bare soil. Shoot dry weight of peanuts, length of branches, number of pod bearing branches, number of pods per square meters, pod yield, 100 pod weight, 100 seed weight, and seed yield in weed free plots from 28 days after seeding to harvest (28 DAS-Harvest) were higher compared to weed free plots from 42 DAS-Harvest. However, in the weed free plot from seeding to 42 days after seeding seed yield was lower than that of the continuous weeding plot due to lower number of pod bearing branches and number of pods per square meters. When weed was not controlled at the later growth stages of peanuts, reduction in seed yield due to weeds was greater in bare soil than that under P.E. mulch.

• Weed & Turfgrass Science
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• v.4 no.2
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• pp.104-110
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• 2015

This study was conducted for 3 years in an apple orchard to investigate the efficacy of the glufosinate-ammonium (GFA) SL for weed control in comparison to non-woven fabric mulch, sod culture and machinery cutting treatments. Glufosinate-ammonium SL 18% was applied with 2 to 3 times, and the extents of injury caused by the different weed control methods were also investigated during the 3 years. The highest level of weed control was obtained by glufosinate-ammonium 3 times spray (98.7%), followed by machinery cutting (95.1%), glufosinate-ammonium 2 times spray (81.5%) and natural sod culture (5.8%). Amounts of fruit production in three times application of glufosinate-ammonium 540 g a.i. $ha^{-1}$, twice application of GFA, machinery cutting, non-woven fabric processing, sod culture and untreated control were 27.2, 26.2, 25.3, 24.1, 20.4 and 13.3 kg, respectively. There was no toxicity symptom of glufosinate-ammonium on the whole tree such as fruit, bud, trunk, branch and flower during the 3 years.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.723-734
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• 2010

This study aims to analyze the change in vegetation for 10 years after the construction, targeting Suwoncheon, the first domestic ecological stream construction project. As for the section for the study, the section from Gyeonggi bridge to Youngyeon bridge, the first restoration project section, was targeted. The research districts consisted of 3 districts depending on topographical structure. Investigation check cosisted of cross-sectional topographical structure, vegetation status and the structure of herbaceous plant community. As for the cross-sectional topographical structure of the stream, the width of entire stream was 26.5~28.0m and water channel is 10~20m. The area for hydrophilic space was securing spacious riverside. Upper stream of reservoir beam was shallow and slow in reservoir area above weir. Lower stream of reservoir beam, the width of water channel was narrow and ripples were formed. Among species, 9 plants were planted and 6 species plants including Salix gracilistyla, Phragmites communis and Zoysia japonica were planted at the time of construction. In the water side, there were 2 species, such as Zoysia japonica and Trifolium repens, etc, still remained after seeding at the time of constrcution. The planted plants which were observed through this investigation, were 2 species such as Festuca arundinacea and Dactylis glomerata. Apart from the planted plants, arid climate herbaceous plant such as Setaria viridis and Artemisia princeps var. orientalis formed power and the naturalized species variously emerged in 15 species. For revetment, natural stone stacking method was condicted and Salix gracilistyla, Aceriphyllum rossii, etc were planted. But all the planted plants disappeared and now it was covered with Equisetum arvense and Humulus japonicus. It was because that the base for growth and development of the plants was not constructed at the time of restoration in a way of attaching natural stones onto the concrete base. In the water channel, various wetland species including Typha orientalis, Acorus calamus var. angustatus and Phragmites communis, etc, were planted but only Salix gracilistyla, Phragmites communis and Zizania latifolia remained. As for species of the autochthons, Persicaria thunbergii was dominant. In the lower stream of reservoir beam, Humulus japonicus formed forces. In the hydrophilic space, it was necessary to direct the landscape of in-stream vegetation in cosideration of users. For this, planting Miscanthus sacchariflorus in a community was proposed. In the upper stream of reservoir beam, suplementary screen seeding was necessary so that Zizania latifolia, Typha orientalis and Phragmites communis can fit the depth of water. In the Lower stream of reservoir beam, it was necessary to constantly manage Humulus japonicus so that the wetland autochthons species, such as Phragmites communis and Persicaria thunbergii can establish power more stably.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.715-728
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• 2023

Tracksite of pterosaurs, birds, and dinosaurs in Chungmugong-dong in Jinju was designated as a natural monument in 2011 and is known as the world's largest in terms of the number and density of pterosaur footprints. This site has been managed by installing protection buildings to conserve in 2018. About 17% of the footprints of pterosaur, theropod, and ornithopod in this site under management in the 2nd protection building are of great academic value, but observation of footprints has difficulties due to continuous physical and chemical damage. In particular, the accumulation of milk-white contaminants is formed by the gypsum and air pollutant complex. Gypsum remains evaporated with a plate or columnar shape in the process of water circulation around the 2nd protection building, and the dust is from through the inflow of the gallery windows. The aqueous solution of gypsum, consisting of calcium from the lower bed and sulfur from grass growth, is catchmented into the groundwater from the area behind the protection building. Pollen and a few minerals other constituents of contaminants, go through the gallery window, which makes it difficult to expel dust. To conserve the fossil-bearing beds from two contaminants of different origins, controlling the water and atmospheric circulation of the 2nd protection building and removing the contaminants continuously is necessary. When cleaning contaminants, the steam cleaning method is sufficiently effective for powder-shaped milk-white contaminants. The fossil-bearing bed consists of dark gray shale with high laser absorption power; the laser cleaning method accompanies physical loss to fossils and sedimentary structures; therefore, avoiding it as much as possible is desirable.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.258-264
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• 1994

The weed survey in lowland rice field in 1992 was conducted to identify weed population change as affected by different elevation, soil type and cultivation pattern at Gangweon province. There were more perennial weeds in plain and east coastal area while more annual weeds in mid alpine and alpine area. Meanwhile, perennial weed species was more dominant at ordinary and sandy soil but annual weed species was more dominant at poorly drained soil. In general, hand and machine(30 day old seedling) transplanting would result in higher dominant weed species of perennial while there was more annual weed species in machine (10 day old seedling) transplanting and dry seeding, respectively. Also, annual weed species was more predominant at spring plowing time compared to autumn plowing time. Particularly, there was change in dominant weed species with time. In 1971 annual weed species was more predominant but perennial weed species was highly dominant in 1981 and 1992.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.1
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• pp.28-43
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• 2022

This study classified UAV image-based physical spatial types for parks in urban areas of Changwon City and analyzed thermal comfort characteristics according to physical spatial types by comparing them with ENVI-met thermal comfort results. Physical spatial types were classified into four types according to UAV-based NDVI and SVF characteristics. As a result of ENVI-met thermal comfort, the T_MRT difference between the tree-dense area and other areas was up to 30℃ or more, and it was 19. 6℃ at 16:00, which was the largest during the afternoon. As a result of analyzing UAV-based physical spatial types and thermal comfort characteristics by time period, it was confirmed that the physical spatial types with high NDVI and high SVF showed a similar to thermal comfort change patterns by time when using UAV, and the physical spatial types with dense trees and artificial structures showed a low correlation to thermal comfort change patterns by time when using UAV. In conclusion, the possibility of identifying the distribution of thermal comfort based on UAV images was confirmed for the spatial type consisting of open and vegetation, and the area adjacent to the trees was found to be more thermally pleasant than the open area. Therefore, in the urban planning stage, it is necessary to create an open space in consideration of natural covering materials such as grass and trees, and when using artificial covering materials, it is judged that spatial planning should be done considering the proximity to trees and buildings. In the future, it is judged that it will be possible to quickly and accurately identify urban climate phenomena and establish urban planning considering thermal comfort through ground LIDAR and In-situ measurement-based UAV image correction.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.6
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• pp.37-48
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• 2021

Roadside pollution has been identified as the main cause of PM_2.5 in urban areas. Green infrastructure has been understood to mitigate air pollution from roadside traffic effectively, but complication depend on environmental variables. This study aimed to investigate the characteristic of PM_2.5 by the type of space in an urban park located in Songsanghyeon Plaza, surrounded by a 12-lane road on all sides. Type of space was typically classified as roadside square (A), sunken square (B), a mix of trees and hedges/shrubs (C), trees only (D), and grass square (E) according to the land-use type and layers of trees. PM_2.5 was measured for nine days, three days for three different Air Quality Forecasts-Good level (0~15㎍/m³), Moderate level (16~35㎍/m³), and Unhealthy level (36~75㎍/m³). The analysis result was as follows. At good levels, there was statistical significance in the order of D, E < B, C < A. In the case of moderate levels and unhealthy levels, D and E were statistically lower than other land-use types. The characteristic of PM_2.5 in the urban park by type of space was affected by atmospheric flow into the road. The relatively high concentration of A and C was located near the roads. Although B was far away from the road, the reason for the high concentration of PM_2.5 was that no structures blocked the air pollution. Thanks to the type of space C, filtering the air pollution from the roads, the concentration of PM_2.5 in D and E was relatively low.

• Korean Journal of Weed Science
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• v.8 no.2
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• pp.208-216
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• 1988

This study was conducted to select herbicides safe for cucurbitaceae crops under the polyethylene film mulching culture. No crop injury with ethalfluralin (N-ethyl-N-(2-methylally)-2, 6-dinitro-4-(trifluoromethyl) aniline) was found in gourd, water melon, cantaloup, cucumber and pumpkin of direct seeded culture. There was no significant reduction in fresh weight of gourd and pumpkin at the rate of 1080 g a.i./ha, that of water melon, cantaloup and cucumber at the rate of 720 g a.i./ha. Napropamide (N,N-diethyl-2-(${\alpha}$-naphthyloxy) propionamide) did not cause any crop injury at the rate of 1500 to 3000 g a.i./ha. There was no significant reduction in fresh weight of gourd, pumpkin and cucumber at the rate of 3000 g a.i./ha, and that of cantaloup and water melon at the rate of 1500 g a.i./ha. Trifluralin (${\alpha}$, ${\alpha}$, ${\alpha}$-trifluoro-2,6-dinitro-N, N-diprophlaniline) did not cause any crop injury in gourd. When ethalfluralin, napropamide and nitralin were applied to the transplanted seedlings of water melon and cantaloup, no significant reduction in the fresh weight were observed. The weeding effect greater than 90% was obtained with ethalfluralin at 720 to 1080 g a.i./ha and pendimethalin (N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine) at 1268 g a.i./ha. The rest treatment gave the weeding effect ranging from 81 to 90%.