• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4649-4655
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• 2010

The aim of this study was to investigate the effect of flowing the industrial wastewater effluents into the K lake which is located in the A city on the eutrophication. The lake was modelled as a continuous stirred-tank reactor. Phosphorus and Chl-a concentration in the lake were calculated to $0.29\;/m^3$과 $4.0\;g/m^3$ at steady state, respectively. Those simulated concentrations were very close to the monitored mean concentration of the lake, indicating that the simulation could be used a tool for characterizing the lake. The non-steady state concentrations of the phosphorus and Chl-a were proposed as a function of time as well. Phosphorus loading ($L_p$) and depth to retention time ratio ($H/{\tau}w$) was calculated in order to analyze the current state of eutrophication. We proposed a strategy to change the lake from eutrophic to permissible oligotrophic state using a graph consisting of two variables, $L_p$ and $H/{\tau}w$.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.51-60
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• 2016

This study was selected drought tolerant plants, by observing the physiological characteristics and biochemical materials from the 9 kinds of the Compositae plants. After selecting plants of the similar size, and then drought stress was induced by the irrigation stopping. Survival rates, chlorophyll values, relative water content(RWC), excised-leaf water loss(ELWL), proline, reducing sugar were measured after 30 days of stopping irrigation. The species that had high rates of survival were Ainsliaea acerifolia Sch. Bip, Aster koraiensis, Aster scaber, Dendranthema zawadskii(S), however other 5 species were dead. The remaining factors have been determined based on plant species showed a higher survival rate. However, chlorophyll content showed high values in A. acerifolia, A.altaicus var. uchiyamae, A. koraiensis, and will have been determined that has no correlation with survival rates, except for A. acerifolia and A. koraiensis. On the other hand, A. scaber, A. acerifolia, A. koraiensis were determined to be relatively high drought tolerant plants in RWC, ELWL, proline, reducing sugar, it showed a similar correlation with survival rate. As a result of 9 kinds of the Compositae plants A. scaber, A. acerifolia, A. koraiensis were considered relatively higher drought tolerant plants.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.100-104
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• 1983

Responses of barley cultivars including 8 covered barley cultivars and 8 naked barley cultivars to butachlor, terbutryn, and methabenzthiazuron were evaluated by determinating crop injury, dry weight and chlorophyll content of barley seedlings. Most barley cultivars were tolerant to butachlor at 1478 ai/10a (recommended rate) but Olbori, Dongbori, and Gangbori were slightly sensitive to butachlor at 294g ai/10a. Sensitivity to terbutryn was generally greater in naked barley cultivars than hulled barley cultivars. Dongbori, Buhobori, and Bunong of hulled barley and Bangsa #6, Kwangseung, Nonsangwa # 1-6, and Iri #4 of naked barley were highly sensitive to terbutryn at 350g ai/10a (double dosage). Most barley cultivars were relatively tolerant to methabenzthiazuron except Iri #4. Dry weight of barley seedlings was not reduced by butachlor, terbutryn, and methabenzthiazuron at recommended rate. However, terbutryn at 350g ai/l0a greatly reduced dry weight of all barley cultivars, especially naked barley cultivars. Chlorophyll content of Owealbori, Dongbori #1, Jogangbori, Bangsa #6, Backdong, and Kwangseung was slightly reduced by butachlor. Terbutryn at 175g ai/10a reduced chlorophyll content of Owealbori, Olbori, and Nonsangwa #1-6 and all cultivars were greatly reduced by terbutryn at 350g ai/10a. Methabenzthiazuron slightly reduced chlorophyll content of Jogangbori, Dongbori #1, Owealbori, Backdong, Kwangseung, and Nonsangwa # 1-6.

• Horticultural Science & Technology
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• v.17 no.1
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• pp.29-32
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• 1999

This experiment was conducted to investigate the effect of different levels of shading (0, 35, 55, 75, 95% to incident sunlight) on the growth of Hedera rhombea Bean and Pachysandra terminalis Sieb. et Zucc. in order to determine optimum light intensity for ground cover plants. H. rhombea showed a upright growth type under 95% shading and P. terminalis was highest under 35% shading. Number of branches was not significantly affected by shading levels. Stem diameter and length were reduced under shading from 35% to 95%. Leaf growth was vigorous under 35% and 55% shade condition. Leaves became longer with decreasing light intensity, but shorter in 95% shading than control. There was a slight trend that total chlorophyll and chlorophyll a, b contents increased with decreasing light intensity, and so did chlorophyll a/b ratio. Fresh and dry weight of both plants were higher under 35, 55, and 75% shading than control and 95% shading. Specific leaf weight tended to decrease with reduction of light intensity. Thus, optimum light intensity for growth of them may be 35 and 55% shading of incident sunlight. In addition, it is possible to grow them under even 75% shading of incident sunlight.

• Journal of Korean Society of Forest Science
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• v.76 no.3
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• pp.230-240
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• 1987

Half-sib seedlings of Ginkgo biloba (one-year-old) were treated with various simulated acid rains(pH2.0, pH3.0, pH4.0 and pH5.0) to examine the effects of acid rain on leaf surface area, leaf injury, leaf chlorophyll content and photosynthetic ability of the leaf tissue. The seedlings were grown in a pot($4500cm^3$) containing one of three different soils(nurseryy soil, mixed soil and sandy soil). Simulated acid rain was made by diluting sulfuric and nitric acid solution($H_2SO_4:HNO_3=3:1$, V/V) with tap water and tap water(pH6.4), and treated by 5mm each time for three minutes during the growing seasons(April to October 1985). Acid rain treatments were done three times per week to potted seedlings by spraying the solutions. The results obtained in this study were as follows : 1. Leaf surface area per seedling at pH2.0 level was the lowest among the levels of pH, but those at other pH levels were not significantly different. 2. Leaf injury(injured leaf rate and injured leaf area) increased with decreasing pH levels of acid rain. 3. Leaf chlorophyll content measured during the period June through October was significantly different among the soil types, and that of the seedling in nursery soil was the highest. The lower pH levels of simulated acid rain was treated ; more leaf chlorophyll content was measured at the beginning of treatment, and the more it severely decreased at the late growing period. 4. Photosyntetic abilities, and the highest value was shown in nursery soil. Significand difference in photosynthetic ability among the levels of pH was observed only in August. Photosynthetic ability increased with decreasing pH levels at the beginning of treatment, but decreased rapidly after July.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.4
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• pp.314-322
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• 2012

In order to elucidate temporal variations of temperature, salinity, pH, dissolved oxygen (DO), suspended particulate matter (SPM), dissolved inorganic nutrients, and chlorophyll a, we performed 25-hour continuous monitoring in the Seomjin River Estuary in March (dry season) and July (rainy season) 2006. We also investigated spatial variations of marine environmental parameters across a saline gradient. In the Seomjin River Estuary, continuous monitoring results revealed that salinity variations were mainly affected by tidal cycle in the dry season and by river discharge in the rainy season. In the dry season, the spatio-temporal distribution of dissolved inorganic nutrient (nitrate, nitrite, and silicate) concentrations showed a good correlation with tidal cycle. While nutrient concentrations in rainy season showed not much variance in time. There were 6 and 4 times higher dissolved inorganic nitrogen and phosphorus concentrations in the rainy season than those in the dry season, respectively. Silicate concentration was 43 times higher in the rainy season than that in the dry season. Chlorophyll a concentration was higher in the dry season than that in the rainy season showing high nutrient concentrations. The results of this study, spatio-temporal variations of marine environmental factors are determined by both tidal cycle and river discharge. It seems that chlorophyll a concentration is related to the river discharge than dissolved inorganic nutrient distribution.

• Journal of Conservation Science
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• v.26 no.3
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• pp.259-268
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• 2010

To evaluate the biological pollution class, Chl-a concentration and color were examined in 8 stone cultural heritages of Korea from April to June 2007. In the case of Chl-a, it had the range of 16.2 to $136.6{\mu}g{\cdot}g^{-1}$, and for the range of the colors, it came out from green to black. As the result of the evaluation, the Three storied stone pagoda in Mulgeol-ri and the Three storied stone pagoda in Suta Temple both showed class 3 and the other 6 stone cultural heritages showed the classes above 4, proving severe biological pollution. The total of 32 aerial algae taxa were found in 8 stone cultural heritages. Out of the 32 taxa, 16 taxa were found in Cyanophyceae, 13 taxa in Chlorophyceae, and 3 taxa in Bacillariophyceae. The correlation coefficient showed 0.43, as a result of the correlation analysis between Chl-a and the biological pollution class. Two among all the aerial algae taxa, Trebouxia sp, and Chroococcus bituminosus, showed high correlation coefficients of 0.89 and 0.65 with Chl-a, in the correlation analysis. High correlation coefficients from 0.54 to 0.65 were shown in a correlation analysis between the biological pollution class and the aerial algae taxa, which are Chroococcus bituminosus, Aphanocapsa grevillei, Xenococcus acervatus, Chlorella vulgaris, and Synechocystis pevalekii.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.223-228
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• 2010

This experiment was conducted to select optimal cultivars of long leaf vase life for flower arrangements among 21 Hosta cultivars that were selected based on their ornamental value. As a result of the investigation, the cultivar with the longest leaf vase life was 'June' with 29 days record. The cultivars with a more than 10 days record were 'Remember Me', H. lancifolia var. grandiflora, 'Grand Marquee', 'Dress Blue', 'Blue Dimples', 'Frosted Dimples', 'Birchwood Park's Gold', 'Krossa Regal', and 'Paradise Power'. These 10 cultivars had a high chlorophyll content, and had low chlorophyll content changes over time and were high in water absorption. The 10 selected cultivars had equal characteristics of increase in chlorophyll content within a certain period of time. These cultivars have a longer vase life when compared to others. This indicates the potential to develop better materials be use with flower arrangements.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.195-201
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• 2011

The seaweed (Ascophyllum nodosum) extracts and chitosan formulations were sprayed on species of creeping bentrgass (Agrostis palustris Huds) cultivar "Penn A1" and species of Kentucky bluegrass (Poa pratensis L.) mixed cultivars (Midnight 33%, Moonlight 33%, Prosperity 33%) during fall season in sod farm. Turf color, chlorophyll contents and NDVI (Normalized Difference Vegetation Index) to affect turf qualities were investigated. There were detected significantly difference on chlorophyll contents and DNVI with seaweed extracts and chitosan formulations treatments. The contents of chlorophyll and NDVI on species of Kentucky bluegrass mixed cultivars and species of creeping bentgrass cultivar "Penn A1" were significantly increased by foliar spray with chitosan formulations and seaweed extracts. There was not a significantly difference on leaf color in two species within cultivars. These results suggested that chitosan formulations and seaweed extracts may help for turfgrass managements in the golf course during fall season.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.1
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• pp.76-87
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• 2014

Chlorophyll a in seawater which is an indicator of phytoplankton biomass and primary production is determined by High Performance Liquid Chromatography (HPLC), Fluorometry and Spectrophotometry. In this study, various methods for chlorophyll a determination in seawater are compared using in situ seawater samples from Korean seas. Three inter-laboratory comparison campaigns were carried out using chlorophyll a standard samples (R0) and in situ seawater samples, collected from the East China Sea (R1) and the East Sea (R2). 6 laboratories by HPLC methods, 4 laboratories by fluorometry, and 3 laboratories by spectrophotometry participated. Precisions, defined as the coefficient of variation (CV) were within 9% in standard samples, 0.8~20% (average: 6.1%) in R1, 4~21% (average: 13.2%) in R2. Discrepancy in three methods was approximately 20% within the range of the sample homogeneity intended the laboratory precision (R1: 8%, R2: 15%). The discrepancy in laboratories was greater than the discrepancy in methods. The chlorophyll a concentrations can be produced within 20% discrepancy in spite of using different methods. It is recommended to consider this 20% discrepancy when using the chlorophyll a data produced by different laboratories and different methods.