• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.43-51
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• 1976

Marine deposite soil was studied to evaluate morohological changes of paddy rice under subdrainage control. The content of organic and inorganic mate rial were low at high temperature in the mid-summer. This soil lacked air and accumulated more H$_2$ S. Thus rice root was rotted with high infection of virus and insect and yield was relatively low.

• Journal of Korean Society of Forest Science
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• v.31 no.1
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• pp.43-47
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• 1976

This study was carried out to find out the effect of soil and water storable pits on reducing the surface runoff. 10 pits were digged in each plot of $50m^2$ along contour line. One kind of pits has a size of 30 cm width, 100cm length and 30cm depth, and the other has 30cm width, 100cm length and 20cm depth. 1. The soil and water storable pits have a significant effect on reducing surface runoff. Control plot had surface runoff 2.3-2.6 times more than the plots with pits. 2. There is no significant difference in surface runoff between 30cm depth pit and 20cm depth pit. 3. The soil and water storable pits did not have any effect on coverage, survival and growth of three species. 4. Steep slope had worse results than the other slopes in coverage, growth and fresh weight of experiment species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.223-228
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• 1982

Experiments were conducted to study the interrelationships between root development of rice plant and water managements at saline paddy field where has been grown rice plant for 3 years, and to compare the root development between two fields, saline and matured. Under the conditions of non interval and two day interval flooding at saline paddy fields, root systems developed well at surface soil, however, root systems developed well and distributed evenly through surface and sub-soil at saline field where underground drainage was performed, and at matured field. Root developments at field flooded with no interval and with two-day interval were poor as compared with those of saline paddy field of underground drainage and matured field. Regardless of water managements and fields, the ratio of stunted crown roots developed after panicle fromation stage was higher than that developed at early or middle growth stage.

• Korean Journal of Agricultural Science
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• v.2 no.1
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• pp.101-110
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• 1975

This study was carried out to determine the effect of water control on Rice plan in warmer season(July~August). The results are summarized as follows; 1. Compared to ordinary watering methods, a constant irrigation method indicated a decrease in water temperature of $1.5^{\circ}C$. 2. In the plot of constant irrigation, there was an increase in the root system in general and an increase of root distribution near the surface in particular. The near surface root distribution under ordinary watering method shows about forty percent distribution. The constant irrigation method shows a near-surface root distribution of sixty-percent within a perimeter of five centimeters. 3. Under the contants irrigation method, there was an increase in length and area of the flag leaf. 4. The total nitrogen and silica content of leaf-bodies at maturing stage was greater when using the constant irrigation method. 5. There was an increase in the number of panicles and the number of spikelets when using the constant irrigation method. 6. The yield was remarkably increased with constant irrigation.

• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.1-6
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• 1987

A pot experiment was conducted to find out the effect of water management on the growth and uptake of arsenic and inorganic nutrients of rice plant at As added soil. The arsenic were added to soil at the levels of As 0, 10, 50, 100 and 150 ppm, respectively. Water management was done with two ways: intermittent irrigation from ten days after transplanting, and continuous submersion until harvest. Higher soil As levels increased As content in plant but reduced growth rate. Aresenic content in plant was considerably reduced with intermittent irrigation compared to continuous submersion. Rice growth showed also same trend. With increasing As levels in soil, N content in plant was increased but P, K, Ca, Mg, $SiO_2$, Fe and Mn content in plant were tend to be decreased. These inorganic nutrients in plant were also much absorbed in continuous submersion compared to intermittent irrigation. Soil pH was slightly increased with increasing As levels in soil while soil Eh has no relationship with soil As levels. On the other hand, soil pH was higher in the treatment of continuous submersion than that of intermittent irrigation but soil Eh showed reverse trend. With increasing As levels in soil, water soluble-As and Ca-As fractions in soil tend to be increased with continuous submersion, but these fractions has no tendency with intermittant irrigation.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.1-15
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• 2020

This study was designed to come up with a way of managing a cultural landscape forest by conducting research on the vegetation structure and growth characteristics. This study's target site, which was 45,201㎡ in size, was Pinus densiflora forest for Sugumagi placed at the entrance of Unmun Temple, Sinwon-ri, Unmun-myeon, and Cheongdo-gun in the southernmost part of Gyeongsangbuk-do, Korea. Sugumagi means the water of the valley flows far away, and where no downstream is visible according to feng shui. The historical sources of the Sugumagi Pinus densiflora forest at the entrance of Unmun Temple isn't clear. It waw only found at that location. The Pinus densiflora forest at the entrance of Unmun Temple is located in the waterway in terms of Feng Shui. The present condition of growth was investigated through a grid surveys of 98 trees and Pinus densiflora growth. As a result of the analysis of growth status, Pinus densiflora, Larix leptolepis, Zelkova serrata, Celtis sinensis, and Rhus javanica were distributed in the conopy layer, and 28 species including Ailanthus altissima were grown in the understroy layer, and 92 species, including Ampelopsis brevipedunculata, in the shrub layer. The plant community structure was divided into low, medium and high-density Pinus densiflora forests in the study area, based on the number in the conopy layer and the grade of and the trees analyzed. As a result of the analysis, the Pinus densiflora dominated the low, medium and high-density Pinus densiflora forests, and there were no competitive species. The relative dominance of the low-density Pinus densiflora forests was 46.9% on average, medium-density was 62.6% and 50.2% was found in high-density. The mean species diversity of Shannon in the low-density study was 0.7055, medium-density study was 0.8966 and the average species diversity of Shannon in the high-density study was 0.8317. The analysis of the age and growth of 25 sample trees in the Sugumagi Pinus densiflora forest shows that the distribution of the chest diameter (DBH) of the sample Pinus densiflora is 38 to 77cm with the average chest diameter being 61.1cm. The age was 84-161 years and the average was 114 years. In the Pinus densiflora forest, most(670,659, or 98.3%) of the tree trunk wound was collected for rosins during the Japanese colonia Era, Of the total 670, 659 were Pinus densiflora, 98.3% of the total. 394 were surgically repaired in 2005. For the preservation of the Sugumagi Pinus densiflora forest, dead trees should be replaced with substitute trees appropriate to the middle and south topography. It is demanded that foreign species such as Larix leptolepis in the research area should be removed and Pinus densiflora that underwent surgical operations should be regularly sterilized. It is also emphasized that the management of insecticide is important.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.497-508
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• 2006

This study was conducted to obtain the basic information on rice cold damage and relationship to be connected with cold tolerance. The 20 rice varieties were screened to cold tolerance under low water temperature condition. The water gradient were controlled to $17^{\circ}C$ at the inlet and $21^{\circ}C$ at outlet of screening field. In the relationship between cold water irrigation and growth of rice varieties, effect on medium maturing cultivars were higher than early maturing cultivars. In relationship of shorting of culm length and panicle exsertion, culm length and panicle exsertion showed positive correlation. Yield of cultivars and culm length and percent of fertile grain showed positive correlation. However, heading date presented negative correlation. In the early maturing cultivars, except 'Kumobyeo', all cultivars range of discoloration value (1-3) was resistant. In the medium maturing cultivars, 'Donghaebyeo' was resistant in both the seedling stage whereas 'Hwajinbyeo' was resistant only in tiller stage. Cold water irrigation reduced spikelet number per panicle and percent of filled grain. Unhulled rice yield was increased according to water temperature gradient from inlet to outlet. There was varietal differences in head rice recovery by cold water treatment.

• The monthly packaging world
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• s.119
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• pp.102-109
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• 2003

• Korean Architects
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• no.4 s.336
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• pp.26-27
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• 1997

• The monthly packaging world
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• s.98
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• pp.164-172
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• 2001