• The Korean Journal of Ecology
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• v.28 no.3
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• pp.141-147
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• 2005

To clarify seed distribution in sediment and its burial properties of Suaeda japonica, the vertical and horizontal distribution of seeds, organic content of sediment, and sediment content delivered by crabs were studied in mud tidal-flat of Walgot-dong, Siheung, Gyeonggi Province, from March 1999 to October 2000. The 94% and 6% of S. japonica seeds were buried under and outside the maternal plant crown, respectively. Organic matter contents of sediment were higher at the area (17%) covered than at the one (8%) uncovered by S. japonica. In the area covered by S. suaeda, organic matter profiles of sediment showed vertical variation from 19% in surface (1 cm depth) to 14% in 6 cm depth. S. japonica seeds buried in sediment decreased from 45% in 2 mm depth to 0% in 12 mm depth. The density of crabs was higher in the vegetated area than in the non-vegetated one. Especially, the density of Cleistostoma was about 8 times higher in the former than in the latter In the vegetated area, the amount of sediment delivered by crabs was estimated to be 2,409 $cm^3{\cdot}m^{-2}$, and this could ascend the height of sediment to 2.4 mm. Consequently, it might be interpreted that plant debris (organic matters) of maternal plants and sediment delivered by crabs made the S. japonica seeds bury well. By relationship between crab distribution and vegetation, it was thought that crabs got a benefit from S. japonica.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.45-52
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• 2019

As international criteria and standards are required in the fields of design and construction, landscape performance must also be considered not only for the value of the landscape but also for providing quality assurance and sustainability. Given the lack of research on landscape performance, the present research was purposed to analyze the importance of potential assessment categories and items using an analytical network process. A list of assessment items, which is composed of 20 items and 6 categories, was derived through a literature review and a preliminary survey of 11 landscape professionals. An ANP model was established and a survey was conducted among 30 landscape practitioners to determine the weight of priorities considering the criteria. The results of ANP showed that the categories of site selection, preservation and health, and convenience had high priorities while materials had the lowest importance score. For the assessment items, a monitoring plan was the highest importance, followed by cultural/ historic preservation, management cost reduction, and natural ground areas. Despite the difficulties in quantifying landscape achievements, most respondents agreed that there needs to be an evaluation system for landscape performance in order to assure the quality and sustainability of landscape development. More research and discussion are needed to develop an assessment system for landscape performance that is applicable to Korean context.

• Korean Journal of Environmental Agriculture
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• v.11 no.3
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• pp.177-184
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• 1992

To investigate differences in lead contents of paddy soils and rice plants affected by municipal and industrial waste water pollution in Mangyeong River area, soil and plants samples were collected in 1982 and 1990 according to the distances from the main inlet source and depths of soil. Soil samples were extracted with ${4H-HNO}_3$ and plant sampler were digested with mixture of ${HNO}_3$ and ${HCIO}_4$ for analyzing by atomic absorption spectrophotometry. The Pb contents in soils ranged from 13.2 to 56.4 mg $kg^{-1}$. Average Pb level in 1990 was some higher than that in 1982. Variation of Pb content with the distances from the source of waste water showed decreasing tendency wish distances, and it was clearer in 1990 than in 1982. A significant correlation was observed between Pb contents in surface and in subsurface soil, between Pb content in soils and soil properties as clay, OM, and $Ca^{++}$ in 1982, and between Pb content in soils and contents of Cu and Zn in soils. The average Pb content in leaf sheath was 3.42 times of that in brown rice. Pb content in brown rice ranged from 3.1 to 10.4mg $kg^{-1}$.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.273-281
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• 2010

Concentration of antibiotics including a tetracycline group (TCs) of tetracycline (TC), chlortetracycline (CTC), and oxytetracycline (OTC), a sulfonamide group (SAs) of sulfamethoxazole (SMX), sulfathiazole (STZ), and sulfamethazine (SMT), an ionophore group (IPs) of lasalocid (LSL), monensin (MNS), and salinomycin (SLM), and a macrolide group (MLs) of tylosin (TYL) was determined from samples collected from the agricultural soil, stream water, and sediment. For the agricultural soil samples, the concentration of TCs had the highest value among all tested antibiotic's groups due to its high accumulation rate on the surface soils. The lower concentrations of SAs in the agricultural soils may be resulted from its lower usage and lower distribution coefficient (Kd) compared to TCs. The concentration of TCs in stream water was significantly increased through June to September. It would be likely due to soil loss during an intensive rainfall event and a reduction of water level after the monsoon season. A significant amount of TCs in the sediment was also detected due to its accumulation from runoff, which occurred by complexation of divalent cations, ion exchange, and hydrogen bonding among humic acid molecules. To ensure environmental or human safety, continuous monitoring of antibiotics residues in surrounding ecosystems and systematic approach to the occurrence mechanism of antibiotic resistant bacteria are required.

• Korean Journal of Environmental Agriculture
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• v.26 no.1
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• pp.49-54
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• 2007

This study was conducted to determine effects of composted livestock manure application on soil nutrient change. PVC pot $(30\times100cm)$ was filled with either volcanic ash soil (Gujwa series) or non-volcanic ash soil (Aewol series) and the 20 cm surface soils were applied with composted livestock manures of cattle pig and poultry at the rates of 0, 50, 100 and 150 ton/ha, respectively. After 210 days soils samples of phosphate, potassium, calcium, and magnesium affected by application of the compost. The applied composted were equivalent to the application of organic matter of $23\sim111$ ton/ha and nitrogen of $80\sim450$ ton/ha. Availability rate of phosphate after the application of composted livestock manures ranged from 1.6 to 91.7% according to the different composted. It was much higher in the non-volcanic ash soil than in the volcanic ash soil. Availability rate of potassium fractional recovery rate change ranged from 22 to 94% according to the different manures. It was larger in the composted Availability rate of calcium 38 to 93% and $9\sim90%$ in volcanic ash soil and non-volcanic ash soil, respectively, It was higher in the composted manures followed by cattle and composted pig manures. Availability rate magnesium ranged from 12 to 41% and $1\sim9%$ in volcanic ash soil and non-volcanic ash soil, respectively. The rate was higher in the composted poultry manure followed by pig and composted cattle manures.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.1
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• pp.31-36
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• 1981

This pot experiment was conducted to find out the optimal fertilization ratio of the anions (N : S : P) in various soil conditions. Soil samples were collected from uncultivated mountains and hills where development for grasslands is under consideration. The optimum ratios were computed by the $Hom{\grave{e}}s$ systematic variation technique. The results were summarized as follows : 1. The optimum fertilization ratios of the anions (N : S : P) for the high yields of grass - clover mixed sward at various areas were obtained (Table 5). 2. The grass yields in mixed sward were increased by the increase of specific soil characteristics, CEC, OM, T-N, avail-$P_2O_5$. However. it was not recognizable by the contents of the cations, the base saturation, and the pH. 3. The relatively high yields of clover were positively related to the Ca and Mg contents in soils, and it was a factor of the increased total yields of mixed sward. 4. The relatively high optimum fertilization ratios of S in volcanic ash soil in the Cheju district and P in sediment lithosol in Daegu should be taken into account in determing the fertilization rate for high yield of clover in mixed sward.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.1-6
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• 1983

The results of COLE(Coefficient of Linear Extensibility) measurement on various paddy soils in Korea are summarized as follows; 1. The COLE values of paddy soil in Korea varied from 0.024 to 0.094 in the surface soil while in the sub-surface soils those were ranging from 0.022 to 0.115. The poorer the relative drainage and the finer the texture caused, the greater the COLE values. 2. The matured clayey soils on fluvio-marine plains and local alluvium derived from the Tertiary materials have COLE values more than 0.09 which is demonstrated that the necessity of COLE measurement throughout profiles so that could be considered the characteristic in the characteristic of those soils. 3. The clay content has the highest positive correlation (r=0.81~0.76) values. The content of organic matter, water content at 1/3 bar, Atterberg limits, water stable aggregate etc. also have significant positive correlation with COLE values while the context of sand and silt show negative correlation. 4. Although the COLE values measured on horizontal linear bases were slightly greater than those measured on volume bases practicability was for granted. For more accurate measurement of COLE, it is reasonable to have the average values of COLE calculated from the horizontal and vertical bases.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.81-85
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• 1989

The 113 soils representing the Jisan soil series (fine loamy, mixed, mesic fluventic Haplaquepts) as mapped in Korea were to characterize the Jisan soil throughout its official range which was the range of properties used to establish series limits. The samples were stratified according to master horizon designation for statistical analysis. The means in selected soil properties, horizon thickness, solum thickness, soil texture, clay content, pH, BSP, and horizon sequence, were within acceptable limits. The minimum values were considerably lower than the lower limits of the official ranges while the maximum values were above the allowable amount. The ranges of definition degree which mean the test of proper placement of any marginal limits were 0.687 to 0.929. Thus, Jisan series as mapped from other soil bodies in the field could be seen similarities and understood relationships among individuals.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.64-71
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• 1983

This experiment was carried out to investigate the effect of lime and phosphorus on soil and yield of rice plants in acid sulfate soil. 1. Lime requirement plus phosphorus (20Kg/10a) plot showed 60% increased in yield. 2. The effect of increase was 36% in lime and 15% in phosphorus. 3. pH and Eh were reversed each other by lime application, and lime and phosphorus increased soil reduction. 4. Sixty two percent of root was distributed in top soil (0-5cm) of control plot while it spreaed in sub soil (5-10cm) with high level of lime and phosphorus plot. 5. Soil pH reached maximum at maximum tillering stage and decreased there after approching near to original pH. But lime requirement was about half of original one. 6. There was significant positive correlation between yield silica or phosphorus in soil, which were high with increase of pH. 7. The application of lime and phosphorus increased nitrogen content in plants. When contents of phosphorus in rice plants were high the yield of rice was increased.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.4
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• pp.301-304
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• 1983

Effects of the clay content on soil chemical properties and rice productivity were studied to evaluate the optimum range of clay content from 42 NPK trials conducted by the provincial ORD in 1979. Nutrients content and CEC of the paddy soils were increased with the increase of clay content in paddy soils. Rice yields without NPK application showed a positive linear regression with respect to surface clay content in the paddies, while the relationship between rice yield and clay content with optimun fertilization showed a curvilinear regression, which indicated the maximum yield was observed in loam soils. However, the yield of rice was not significantly different in the range of clay content from 14 to 38%. It implies that the clay content more than 15% may be secondary constraint in determining the soil productivity.