• Korean Journal of Environmental Biology
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• v.19 no.1
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• pp.43-48
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• 2001

Chlorophyll fluorescence of needles of Korean fir (Abies koreana) plants and environmental factors of their natural habitat were investigated in order to obtain the information for environmental adaptation and conservation of Korean fir plants. The photochemical efficiency of photosystem II, Fv/Fm, of Korean fir needles was significantly low (0.19-0.36) in the winter, whereas it was high (0.8-0.86) in the summer. The Fv/Fm value of the winter was slightly higher at mid-day than at dawn, suggesting that mid-day environmental conditions of the winter were favorable on needles of Korean fir plants. In contrast, the mid-day Fv/Fm value of the summer maintained high (around 0.8). It indicates that mid-day environmental conditions of the summer did not induce photodamage, although it caused a slight decrease in the Fv/Fm values. The non-photochemical fluorescence quenching (NPQ) of Korean fir needles was very low (0-0.01) all through the day in the winter. However, it was high (0.76) at mid-day in the summer. These results suggest that Korean fir plants have a system for the protection of PS II from mid-day environmental stresses of the summer. In the winter, the Fv/Fm values were positively correlated with temperature, light intensity and relative humidity, although NPQ values showed no correlation with any of them. In the summer, the Fv/Fm values were positively correlated with relative humidity but negatively correlated with temperature and light intensity. These results indicate that increase of tempera-ture, light intensity and relative humidity lead to promotion of the photochemical efficiency in the winter and high temperature and light intensity may cause photoinhibition in the summer.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.513-521
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• 2019

With rapid climate change and increasing global warming, the distribution of evergreen broad-leaved trees (EBLTs) is gradually expanding to the inland regions of Korea. The aim of the present study was to analyze the survival rate of 148 EBLT plantations measuring 180 ha and to determine the optimal plantation size that would help in coping with climate change in the warm, temperate climate zone of the Korean peninsula. For enhancing the reliability of our estimated survival model, we selected a set of 11 control variables that may have also influenced the survival rates of the EBLTs in the 148 plantations. The results of partial correlation analysis showed that the survival rate of 67.0±26.9 of the EBLTs in the initial plantation year was primarily correlated with plantation type by the crown closure of the upper story of the forest, wind exposure, and precipitation. For predicting the probability of survival by quantification theory, 148 plots were surveyed and analyzed with 11 environmental site factors. Survival rate was in the order of plantation type by the crown closure of upper story of the forest, wind exposure, total cumulative precipitation for two weeks prior to planting, and slope stiffness in the descending order of score range in the estimated survival model for the EBLTs with the fact that survival rate increased with shade rate of upper story to some extent.

• Journal of Bio-Environment Control
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• v.19 no.2
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• pp.97-108
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• 2010

The present study was conducted to investigate photosynthetic responses (Pn), chlorophyll fluorescence (Pe), chlorophyll contents of Allium victorialis var. platyphyllum, Ligularia fischeri, and Ligularia stenocephala growing at four different fertilizing schemes (non-fertilizing and 2.5 $g{\cdot}l^{-1}$, 5 $g{\cdot}l^{-1}$, 10 $g{\cdot}l^{-1}$ fertilizing). Three wild vegetables showed outstanding Pn and Pe at 5 $g{\cdot}l^{-1}$ fertilizing treatment. 10 $g{\cdot}l^{-1}$ of fertilizer, however, proved to be too much eventually leading to declined growth. A. victorialis var. platyphyllum showed good Pn and Pe under shade treatment whereas Pn and Pe of L. fischeri, and L. stenocephala showed the opposite tendency. The chlorophyll contents of the three wild vegetables showed the highest measurement ranging between 11.70~24.36 $mg{\cdot}g^{-1}$ when treated with 5 $g{\cdot}l^{-1}$ of fertilizer. Also it was showed that there were more chlorophyll contents under shade treatment as opposed to full sun. These results showed that 5 $g{\cdot}l^{-1}$ fertilizing treatment is optimal fertilizing of three wild vegetables and fertilizing and light intensity controlling is very important for productivity of vegetables.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.1
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• pp.127-142
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• 2023

The management of size and weight, which are the growth information of aquaculture fish in fish-farms, is the most basic goal. In this study, the epoch is defined in fish-farms from the time of stocking or dividing to the time of shipment, and the growth data for a total of three epoch is analyzed from a time series perspective. Growth information such as the size and weight of aquaculture fish that occur over time in fish-farms is compared and analyzed with water quality environmental information and feeding information, and a model is presented using the analysis results. In this study, linear, exponential, and logarithmic regression models are presented using the Box-Jenkins method for size and weight by epoch using data obtained in the field.

• Korean Journal of Environment and Ecology
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• v.5 no.1
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• pp.25-31
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• 1991

To investigate the structure and the conservation of Abies koreana forest at Banyabong area in Chirisan, 38 plots(100$m^2$) set up with random sampling method. Dead individuals of Abies koreana were 12.81%. were observed mainly upper-layer trees. A few seedlings of Abies koreana were observed. Three groups were classified by cluster analysis. High positive correlations was proved between Abies koreana and Rhododendron mucrolunulatum var. ciliatum, and High negative correlations was proved between Abies koreana and Fraxinus sieboliana, Carpinus cordata, Sasa purpurascens and Cornus controversa. Species diversity(H') of investigated area was calculated 1.9796-2.7509. To conserve Abies koreana forest at Banyabong area in Chirisan. Research and prescription on the declining of Abies koreana was needed and Quercus mongolica, Acer pseudo-sieboldianum, Fraxinus sieboliana, Carpinus cordata, Sasa purpurascens and Cornus controversa in the Abies koreana forest should be cleared out.

• Journal of Environmental Science International
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• v.11 no.10
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• pp.1001-1009
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• 2002

Vegetative characters (e.g. habitat, root, ramification and habit of stem, phyllotaxy, leaf sape, shape of leaf margin, shape of division and lobe of division, number of division, thick and texture of leaf and shape of stipule) on 35 species of Asian Geranium were reviewed to discussion propriety of taxonomic character and evolutionary trends. Wilfordii group is characterized by three divided leaf, Farreri group was grown a high altitude, and Maculatum group is grouped by life cycle of anneal. Arrangement state of leaf is alternate type G, tripartitum, G. eriostemon, and G. erianthum is thought the more primitive than the other taxon, and regarded as more advanced group the sibiricum group and pseudosibiricum group which divided of leaf deeply. Shape of leaf, division degree of lobes, shape of leaf margin and number of division are considered a good identification characters because width of change are fixed between population.

• Korean Journal of Environment and Ecology
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• v.36 no.4
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• pp.422-432
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• 2022

Soil and micro-climatic environmental monitoring was conducted to evaluate the factors causing tree growth impediments at the Baekdudaegan ecological axis restoration project site. As a result, it was found that the nutrient supply was insufficient in the restoration project site due to the lack of organic matter, total nitrogen and cation exchange capacity of the soil compared to the surrounding forest. After the completion of the restoration, the soil moisture in the autumn decreased more than 7 times faster than that of the surrounding forest, and it was evaluated that the soil moisture was significantly low due to the lack of silt and clay content. In the case of the restoration site, the annual potential evapotranspiration was analyzed to be 975mm, which is approximately two times higher than that of the surrounding forest. The soil moisture of the restoration site in the summer decreased rapidly during the daytime when the amount of insolation increased and this was found to be strongly influenced by the increase in potential evapotranspiration. In order to improve the above factors affecting the tree growth at the Baekdudaegan ecological axis restoration project site, it is necessary to induce the smooth supply of nutrients and water to plants by improving physical proprieties and cation exchange capacity, i.e., using litterfall, humus soil, soil conditioner and organic fertilizer. The results of this study are expected to serve as basic data for the design, construction, and management of ecological axis restoration projects in the future.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.248-253
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• 2001

These studies were carried out to examine the developmental process of galls caused by aphids in Rhus gavanica and the effects of indole-3-acetic acid (IAA) and ${\alpha}$-naphthalene acetic acid (NAA) on the tannin accumulation in the callus induced from that galls. The results are follows. The development of fist-shaped galls has begun at the beginning of June earlier than the case of finger-shaped galls, and also, the growth of fist-shaped galls has last to September longer than the period of finger-shaped galls. These results indicate that the life cycle and feeding activity of the aphids inhabited in fist-shaped galls were longer and mire active than the case of the aphids inhabited in finger-shaped galls. Tannin contents of fist-shaped galls revealed about 60${\sim}70%$ of total dry weights during the whole growth periods, however, the contents in finger-shaped galls were under 10% at the maximum value. These facts mean that finger-shaped galls seem to be as a habitat of aphids rather than as a major source of tannin such as fist-shaped galls. The growth of callus induced from fist-shaped galls was the most effective in the plot of $10^{-5}$ mole IAA, but the tannin accumulation in callus growth was not even caused in any plots of IAA treatments as wells as in any NAA plots. These results considered that the tannin accumulation in fist-shaped galls may be caused only in specific relation between host plant and life cycle of aphids.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.1057-1065
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• 2010

Recent urban concerns over environmental problems have furthered interest in green roof system. Plant growth and load bearing capacity of an underlying roof are key factors to determine an optimal system. This study was carried out to develop an optimal extensive green roof system for shrubs assessing the effects of substrate type and soil depth on the growth of $Rhododendron$ $indicum$ Sweet. in the experimental systems with different soil types and depths from 2001 to 2008. Substrate types of perlite alone and blended with sandy loam (v/v, 1:1) were used on the experimental systems with depths of 30 cm, 45 cm, and 60 cm. The survival rate of the plants on the perlite alone + 45 cm soil depth system (RS-A-45) was 100% during the experimental period, while those on the perlite alone + 30 cm soil depth system (RS-A-30) and perlite blended + 60 cm soil depth system (RS-B-60) showed 33% and 67%, respectively, in 2008. The overall plant growth and soil properties of RS-A-45 were superior to the others. At 8 years after installation, the total weight of RS-A-45 including plant fresh weight was about $376.6kg{\cdot}m^{-2}$ in field capacity indicating RS-A-45 can be optimal extensive and light weight green roof system.

• Weed & Turfgrass Science
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• v.5 no.3
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• pp.165-169
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• 2016

To establish the soil management system for the efficient sod production, survey on the growth of zoysiagrass by different soil managements was conducted in repeated cultivation field with regard to soil physical properties. Soils were subjected to four types of management methods, which include (1) rolling (2) topdressing (3) topdressing + rolling (4) topdressing + tillage + rolling. The topdressing + tillage + rolling treatment significantly ameliorated soil physical properties such as bulk density, porosity and solid phase as compared to rolling and topdressing + rolling treatments, and was not significantly different from the topdressing treatment. Further growth and density of zoysiagrass except for the root dry weight in topdressing + tillage + rolling treatment were significantly higher than that only in rolling treatment. Topdressing + tillage + rolling treatment significantly increased the number of shoot as compared to the other treatments. Therefore, combined topdressing and tillage soil management practice should be conducted for the production of zoysiagrass in repeated cultivation field.