• Korean Journal of Weed Science
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• v.13 no.1
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• pp.1-6
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• 1993

The experiments were conducted in order to find out the response of algae as affected by fertilizer and salinity, and to determine the chemical control method of algae in 1991. The higher the nitrogen fertilizer level, the more the occurrence of a blue-green alga Oscillatoria concerning with soil flakes. An increase in phosphorus fertilizer level stimulated the growth of green alga Hydrodictyon, whereas an increase in nitrogen level caused its abrupt reduction due to the harmful effect at high concentration of nitrogen, The high level of nitrogen fertilizer also reduced the growth of Euglena, although the detrimental effect was less compared with that of Hydrodictyon. A blue-green alga Oscillatoria, a green alga Cladophora and a diatom Navicula were tolerant to salinity. Piperophos/dimethametryn was highly effective in controlling various algae such as a green alga Hydrodictyon, suspended unicellular green algae and Euglena species. A fungicide propineb and copper sulfate also effectively controlled Hydrodictyon.

• ALGAE
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• v.27 no.3
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• pp.197-203
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• 2012

A eukaryotic microalga, Asterarcys quadricellulare KNUA020, was isolated from garden soil at Kyungpook National University in Daegu, South Korea and its biotechnological potential was assessed. Optimal growth was obtained when the culture was incubated at $25^{\circ}C$ and around pH 7.0. The total lipid content of the isolate was 15.5% of dry weight and its most abundant fatty acid was nutritionally important C18:3 ${\omega}3$ (${\alpha}$-linolenic acid, ALA). In addition, a high-value fatty alcohol, hexadecenol ($C_{20}H_{40}O$), was also identified in this photosynthetic microorganism. Hence, A. quadricellulare KNUA020 appears to be promising for use in the production of microalgae-based biochemicals.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.2
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• pp.126-135
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• 2013

This study was performed to have an effect on control the growth of algae such as "Actinastrum fluviatile" which occurs frequently in the aquaculture tank using by a cold plasma, and it also would be expected to promote the growth of water plants due to active element causing OH radicals in the water. In addition, it was verified on the death rate as 99.9% on the scale protrusion of "Aeromonas hydrophila" as well as E. coli, especially, under extreme conditions more than 100 million pathogenic bacterium in the aqua pet tank, the ornamental fish had to act in a safe and healthy environment at over 98% death rate within 48 hours. It has been proven to give no affect on aerobic bacteria that exist in the filter or soil because there was no residual toxicity in the water tank. As the results, it will help to develop and apply on the sterilization device in other industries as well as aquarium organisms due to adopted energy-saving algorithm and reliability in use.

• Korean Journal of Weed Science
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• v.12 no.2
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• pp.158-165
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• 1992

A survey on nation-wide distribution of fresh-water algae occurring in paddy rice fields was conducted in 1991. The algae which were collected from the whole nation were classified into a total of 54 genera including 14 genera in the blue-green algae. 29 genera in the green algae, 1 genus in the stoneworts. 3 genera in the euglenoids and 7 genera in the diatoms. The green algae and diatoms occurring in plain regions were diverse in terms of the number of genera distributed, whereas there was no regional difference in diversity of the blue-green algae and the euglenoids. Among the green algae, the suspended unicellular algae such as the genera, Chlamydomonas, Pandorina and Gonium, were widespread in plain regions, but the multicellular algae such as the genera, Spirogyra, Oedogonium, Ulothrix and Hydordictyon, were major in mountainous and attitudinal regions. The filamentous green algae such as the genera. Cladophora and Rhizoclonium, were dominant in reclaimed saline fields. The blue-green algae Oscillatoria spp. and the diatoms Navicula spp. were abundant in soil flakes.

• 한국문화재보존과학회:학술대회논문집
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• 2005.03a
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• pp.62-70
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• 2005

This paper presents the results of a study carried out on the diversity of the living microorganisms colonizing the inside of Gyeongjuseokbinggo(Treasures 66) and their effect on the substrate. The inner walls and the arch were first examined with the unaided eye. Green thick mats of algae and microorganisms covered the great part of the walls. For the laboratory research this green biogenic layer and the next soil layer were collected by scraping the walls and the arch under aseptic conditions. The material was then cultured in laboratory. In result, many different species of bacteria, fungi, algae, cyanobacteria and actinomycetes were isolated from the samples.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.13-18
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• 1995

This experiment was carried out to investigate occurrence ecology and control of soil-flakes in flood-direct seeded rice field. The occurrence of soil-flakes were inhibited in blue light of 450nm wave length and promoted in red light of 660nm wave length. The diatoms of Pinnularia spp. largely occurred in low fertilizer level and which much more increased when nitrogen was mixed with thinly soil depth. The diatoms of Pinnularia spp. were effectively controlled by carbamate and triazine herbicides when treated in pre-emergence of soil-flakes. Beside, triazine herbicides, simetryne, dimethametryn, prometryne 5g ai/10a showed high control effect in pre and post-emergence of soil-flakes. Expecially, In water-direct seeded rice pyrazosulfuron-methyl molinate simetryne 5.37% GR and dimepiperate bensulfuron dimethametryn 7.643% GR showed high control effect on the soil-flakes when treated at 10 days after seeding and didn't showed rice injury.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.93-99
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• 1989

To investigate the effects of barley straw on microflora, acetylene reducing activity, enzyme activity and sugar in relation to nitrogen fixation in submerged soil. The obtained results were summarized as follow: Of the nitrogen fixing microorganisms, the number of Azotobactor tended to increase with the application of barley straw as the rice grew. The number of Clostridia were increased at the tillering stage of plant and decreased thereafter, and that of Blue-green algae tended to increase at the heading stage and to decrease thereafter. On the other hand, the number of Blue-green algae tended to increase by the application of barley straw. Acetylene reducing activity was decreased in the heading stage and increased in the harvesting stage. There was no difference of acetylene reducing activity between the application of barley straw and control. In submerged soil treated with barley straw, enzyme activity of ${\beta}$-glucosidase was increaded significantly but that of phosphatase was not entirely affected. Of the change of enzyme activity, the observation of ${\beta}$-glucosidase was increased at the heading stage and decreased thereafter, and the activity of phosphatase tended to decrease in the submerged soil when rice plants were not cultured and to increase in the submerged soil when rice plants were cultured. Protease tended to increase in the heading stage and increase in the tillering stage and heading stage with the application of barley straw. The change of sugar was decreased and hexose was increased in the tillering stage with the application of barley straw.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.47-50
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• 2009

Nutrient losses, especially nitrogen and phosphorus, in agricultural runoff can contaminate surface and ground water, leading to eutrophication. Thus, erosion control is crucial to minimizing nutrient losses from agricultural land. Assessments of various erosion control practices were carried out under various cropping system, soil management practices, and slope conditions by means of a lysimeter study and under artificial rainfall. Soil and nutrient losses were monitored in a small agricultural field to evaluate the soil conservation practices. Nutrient losses occur in runoff and leachate (dissolved nutrient) and in sediments (particulate nutrient). Dissolved nitrates accounted for the majority (about 90%) of nitrate transport within the soil. Particulate phosphate in sediments represented the majority (60% to 67%) of phosphate transport. Recently, engineering and agronomic erosion-control practices haver been used to reduce erosion problems in fields on slopes. These practices reduced soil loss, runoff, and nutrient loss to 1/6, 1/2,and 1/3 their original levels, respectively. Bioavailable particulate phosphate in sediments represents a variable but longterm source of phosphate for algae. Dissolved nitrate and phosphate are immediately available for algal uptake, so reducing fluxes of these nutrients should also reduce the risk of eutrophication.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.277-284
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• 2018

In 2017, the freshwater algae were collected from reservoirs, small ponds, soil, and rocks in Korea. Eight taxa of Chlorophyta (Chlorophyceae and Trebouxiophyceae) have been newly reported in Korea. The unrecorded indigenous species were Chlorolobion braunii, Coelastrum pseudomicroporum, Coelastrum reticulatum var. cubanum, Monoraphidium nanum, Tetrachlorella incerta, Ecdysichlamys obliqua, Gloeotila scopulina, and Stichococcus jenerensis.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.2
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• pp.149-159
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• 1988

This study was made to investigate the effect of pesticides on microflora to nitrogen metabolism, nitrification and nitrogen fixing activity in the submerged soil. The results are summarized as follows; Pesticides treatment leaded to the inhibition of $NH_4{^-}$-oxdizers, $NO_3{^-}$-reducer, and denitrifying bacteria population. $NO_2{^-}$-oxdizers were inhibited by cabamate compounds, carbofuran and MIPC. Simetryne seemed to stimulate the denitrifying bacteria at 60 days after incubation. Generally, formation of $NO_2{^-}$ and $NO_3{^-}$ tended to decrease by pesticides application. Pesticides application stimulated Azotobacter and Clostridia populations, while simetryne inhibited Athiorhodaceae and Thiorhodaceae. However acephate seemed to be stimulatory to blue-geen algae. $C_2H_2$-reducing activity by acephate was clearly appeared. The change of $C_2H_2$-reducing activity did not seems to be affected by pesticides application.