• Korean Journal of Weed Science
• /
• v.30 no.4
• /
• pp.371-379
• /
• 2010

Crimson clover (Trifolium incarnatum), hairy vetch (Vicia villosa) and rye (Secale cereale) are common leguminous cover crops. Because they contain water-soluble allelopathic substances that show a variable level in tissue depending on growth stage of the plants, the weed inhibition effects are dependent on the growth stage of cover crops. This study investigated the allelopathic effects of crimson clover, hairy vetch and rye on soybean, radish, oilseed rape and lettuce seeds germination and seedling growth. We used extract that were prepared from the shoots of crimson clover, hairy vetch and rye at different growth stages, vegetative growth stage, flowering stage, and fruiting stage. Applications of aqueous extracts from three growth stage of cover crops strongly affected to oilseed rape and lettuce seeds germination but the treatment resulted in a slight inhibition of the germination in soybean and radish. Radical length was more sensitive to aqueous extracts than seed germination rate. Especially, three cover crops extracts at vegetative growth stage highly inhibited seedling root growth of oilseed rape and lettuce by over 80% and 90% respectively. Furthermore, the $GR_{50}$ values were lowest in the treatment of extracts from vegetative growth stage and the level of phenolics was decreased by the order of vegetative growth stage, flowering stage and fruiting stage.

• Korean Journal of Plant Resources
• /
• v.28 no.5
• /
• pp.641-647
• /
• 2015

This study was conducted to select native ground cover plants for sod culture in an organic apple orchard by estimating the effect of three native ground cover plants, Glechoma hederacea, Thymus magnus, and Ixeris stolonifera, on the soil coverage, time-periodic weed occurrence, fruit characteristics, and soil chemical properties. The plant height of G. hederace, T. magnus and I. stolonifera were 15.0 ㎝, 13.4 ㎝ and 7.2 ㎝, respectively. The dry weight of G. hederace, T. magnus and I. stolonifera were 463 ㎏/10a, 247 ㎏/10a, and 255 ㎏/10a, respectively. The plant height and dry weight of G. hederacea were higher than in the other species. T. magnus and I. stolonifera having relatively lower soil cover rate during their life cycle produced a lot of weeds in the orchard as compared with the control. In contrast, G. hederacea showed 100 percentage of ground cover in the first year, and maintained high percentage of ground cover in the growing season of ‘Tsugaru’ apple for another 2 years. When the soil was covered with G. hederacea in the orchard for 3 years, the amount of weed was only 114 ㎏/10a and number of weeding was also reduced about 33% compared with control as well as the other species. There were no differences in the tree growth and fruit characteristics between the native ground cover plants and the control; however, positive effects of native ground cover plants on soil chemical properties were found. In G. hederacea, available P₂O₄content in soils remarkably increased and was a significant difference among native species. In addition, cation (Ca, Mg and K) content in soils increased by 39% in Ca, 6% in Mg, and 11% in K at G. hederacea compared with control. These results suggest that G. hederacea could be advantageous in terms of reducing the amount of herbicide applied and the labor required for weed control, and controlling soil chemical properties; therefore, it is a good candidate for sod culture in an organic apple orchard.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.30 no.5B
• /
• pp.519-524
• /
• 2010

This study was carried out to select suitable plants for beach revegetation as a preliminary study for quantifying the effect of decreasing sand movement. After planting some herbal plants in field, monitoring of temporal change of vegetation coverage which was index of the growth rate was conducted. Through literature reviews, 24 candidate plants for beach revegetation were selected, then seven species of them, Peucedanum japonicum Thunb., Dianthus japonicus Thunb. ex Murray, Sedum oryzifolium Makino, Sedum takesimense Nakai, Sedum spectabile Boreau, Farfugium japonicum (L.) Kitam., Aster sphathulifolius Maxim. were picked through salinity tolerance experiments in laboratory. Seven species selected by salinity tolerance experiments and two additional herbal plants, Prunella vulgaris var. lilacina Nakai and Linaria vulgaris Mill., not the candidates, were nine final species which were planted in the beach around Osan port, Uljin, Korea. The changes of vegetation coverage of each species were investigated from photos periodically taken for about a year using image processing methods. As a result of the monitoring, Sedum takesimensei, Dianthus japonicus and Aster sphathulifolius were observed with high coverages during the whole monitoring while Prunella vulgaris var. lilacina and Linaria vulgaris were observed with low coverage during the same period. Consequently, Sedum takesimensei, Dianthus japonicus and Aster sphathulifolius were concluded as the most suitable plants for beach revegetation. Furthur study to quantify the effects of decreasing sand movement by the selected species is needed.

• Korean Journal of Environment and Ecology
• /
• v.26 no.5
• /
• pp.801-811
• /
• 2012

The purpose of this study is to find out how land cover and planting of an urban park influence temperature. Field research on the land cover and planting status was conducted for Bundang Central Park in Sungnam-si. 30 study plots in the site were selected to closely analyze land cover type and planting structure. The temperature was measured 10 times for each plot. Land coverage type, planting type, planting layer structure and green space area (the ratio of green coverage, GVZ) were chosen as factors impacting temperature and statistics were analyzed for the actual temperature measured. Analysis on how the land coverage type influences temperature showed that planting site had a low temperature and that grassland and paved land had a high temperature. When it comes to planting type, the temperature at the land planted with conifers and broad-leaved trees was low, while the temperature at grassland and paved land was high. With regard to planting layer structure, canopy and canopy-underplanting type showed low temperature, while grassland and paved land showed high temperature. An analysis on the relation between green space area and temperature found out that both ratio of green coverage and GVZ had a high level of negative correlation with the temperature measured. According to regression model of green space area and the temperature measured, for every 1% increase in the ratio of green coverage, temperature is expected to lower by $0.002^{\circ}C$. Also, for every $1m^3/m^2$ increase in GVZ, temperature is expected to go down by $0.122^{\circ}C$.

• Journal of Bio-Environment Control
• /
• v.18 no.4
• /
• pp.326-331
• /
• 2009

This study was carried out to evaluate the effects of row cover materials supported by flexible FRP frames with three kinds of non-woven fabric, and five kinds of net in leaf vegetable cultivation. Leaf radish (Raphanus sativus L.), Chinese cabbage (Brassica rapa L. ssp. pekinensis) were sown on May 21, 2003, and leaf lettuce (Lactuca sativa L.) was planted at the same date in Agricultural Research Center for Climate Change, Jeju, Korea. Net coverings showed higher light transmittance than in non-woven fabric coverings. The average air and soil temperatures increased by $0.3{\sim}1.0^{\circ}C$ in net coverings and $0.5{\sim}3.0^{\circ}C$ in non-woven fabric coverings, respectively. There was no difference in relative humidity among the covering materials. All the vegetables showed higher growths and yields in non-woven coverings than in non-covering. The yields increased 81% in leaf lettuce, 58% in leaf radish, and 93% in Chinese cabbage, respectively. In addition, the insect damages were considerably reduced in the row covering plots than in the control, especially in non-woven fabric coverings.

• The Korean Journal of Soil Zoology
• /
• v.5 no.2
• /
• pp.125-131
• /
• 2000

Disposing technique for dairy cattle manure using earthworms and the possibility of utilizing earthworms in poultry feed were investigated. In addition, chemical properties of manure and cast of earthworms were investigated. Temperature in the vinyl-house for earthworm nursery was able to be maintained above 0$\^{C}$ in winter and 25-28$\^{C}$ in summer. In closed-covering method, the number of escaped earthworms was the highest among three covering methods. The time was longer after manure excretion, the numbers of escaped earthworm were higher. There were some incidences of mortality of earthworm in closed-covering site. The amount of manure ingested by earthworm was increased in order of non-covering, closed-covering and gap-covering method. Fresh manure was more ingested than old one by earthworm. Earthworms reduced manure about 50% on the dry weight base and reduced total amounts of N, P$_2$O$\_$5/ and K$_2$O of manure by 41, 50 and 60%, respectively. Earthworm could be utilized by adult poultry (>60 g) for feeding. However, adverse effect of live earthworm was observed with young poultry (<450 g).

• Korean Journal of Environmental Agriculture
• /
• v.29 no.3
• /
• pp.287-292
• /
• 2010

We aimed to investigate the responses of soil organisms to cover plants and to provide information for the selection of proper plant species. We studied the effects of 7 cover plants, including rye, oat, rattail fescue, Chinese milk vetch, red clover, crimson clover, and hairy vetch, on soil organisms in an apple orchard. An increase in the microbial phospholipid fatty acids (PLFA) and in the number of nematodes and microarthropods in the soil under the cover plants reflects elevated activities of soil organisms. A decrease in the level of some marker PLFA, which is an indicator of environmental stress, suggests that cover plants provide favorable environments for soil organisms. The population of fungi and animals that feed on fungi increased in the soil surface under red clover. The population density of nematodes and mites increased in the soil surface under rattail fescue, and that of mites and omnivorous nematodes increased in the soil surface under Chinese milk vetch. The level of microbial PLFA in the soil surfaces under the tested cover plants was higher than that under clean culture system. These results suggest that proper selection of the cover plants can facilitate the creation of favorable environments for soil organisms.

• Korean Journal of Plant Resources
• /
• v.20 no.4
• /
• pp.331-335
• /
• 2007

This study was conducted to investigate the soil mulching effect on bolting and growth of Angelica koreana Max. The bolting ratio were 8.4% of non-mulching, 11.4% of black polyethylene film, 13.6% of transparent polyethylene film, 6.4% of rice-straw mulching. The mulching of polyethylene film induced higher bolting response than other materials. The radical leaf length, the number of leaf and crown in black P.E. film mulched were all higher than those of non-mulching and rice-straw mulching. The yield of the underground part of P.E film mulching was higher than non-mulching and rice-straw mulching. Comparing with other treatments, the dry root yield of black P.E. film mulching showed the most.

• Korean Journal of Medicinal Crop Science
• /
• v.2 no.1
• /
• pp.14-19
• /
• 1994

Elephant food(Amorphophallus konjac K.) have been utilized its tubers in workedmaterials for a health and diet food. The author supposed that it was increased the area of cultivation and demand. This experiments were conducted to select the proper covering material during winter in order to increase yield of tubers and decrease input by 2 year's continuous cultivation, also to verified ability of seed germination and to measured efficiency of photosynthesis of plant. The proper covering materials for wintering were rice straw and rice hull. These materials were covered at 5 cm thick and at field was promoted according to emergence appearing after winter. The yields were 5,790kg /10a at 4,730kg /10a, respectively. Yield increase was 120% and 80% than that of control. The seeds collected at August 22 were germinated about 84 percent, and it was not necessary to treatment of low temperature or germination-accelerated chemicals. The widest leaf area was ranged $1,218-1,438cm^2$ at October 20 and was varied. The efficiency of photosynthesis was highest at 65-95 days after leaf emergence. The line of broad leaf and high photosynthetic efficiency per unit area was greater compare with yield. Therefore, it was supposed that these characteristics will use a marker for selection for high-yielding lines.

• Korean Journal of Remote Sensing
• /
• v.38 no.6_1
• /
• pp.1035-1046
• /
• 2022

This study evaluated the applicability of multi-resolution data fusion for land-cover classification. In the applicability evaluation, a spatial time-series geostatistical deconvolution/fusion model (STGDFM) was applied as a multi-resolution data fusion model. The study area was selected as some agricultural lands in Iowa State, United States. As input data for multi-resolution data fusion, Moderate Resolution Imaging Spectroradiometer (MODIS) and Landsat satellite images were used considering the landscape of study area. Based on this, synthetic Landsat images were generated at the missing date of Landsat images by applying STGDFM. Then, land-cover classification was performed using both the acquired Landsat images and the STGDFM fusion results as input data. In particular, to evaluate the applicability of multi-resolution data fusion, two classification results using only Landsat images and using both Landsat images and fusion results were compared and evaluated. As a result, in the classification result using only Landsat images, the mixed patterns were prominent in the corn and soybean cultivation areas, which are the main land-cover type in study area. In addition, the mixed patterns between land-cover types of vegetation such as hay and grain areas and grass areas were presented to be large. On the other hand, in the classification result using both Landsat images and fusion results, these mixed patterns between land-cover types of vegetation as well as corn and soybean were greatly alleviated. Due to this, the classification accuracy was improved by about 20%p in the classification result using both Landsat images and fusion results. It was considered that the missing of the Landsat images could be compensated for by reflecting the time-series spectral information of the MODIS images in the fusion results through STGDFM. This study confirmed that multi-resolution data fusion can be effectively applied to land-cover classification.