• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.230-236
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• 2010

Jeju Island is a volanic island which is located about 96 km south of Korean Peninsula. Volcanic ejecta, and volcaniclastic materials are widespread as soil parent materials throughout the island. Soils on the island have the characteristics of typical volcanic ash soils. This study was conducted to reclassify Jeju series based on the second edition of Soil Taxonomy and to discuss the formation of Jeju series in Jeju Island. Morphological properties of typifying pedon of Jeju series were investigated, and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon has dark brown (10YR 3/3) silt clay loam A horizon (0~22 cm), strong brown (7.5YR 4/6) silty clay BAt horizon (22~43 cm), brown (7.5YR 4/4) silty clay Bt1 horizon (43~80 cm), brown (7.5YR 4/6) silty clay loamBt2 horizon (80~105 cm), and brown (10YR 5/4) silty clay loam Bt3 horizon (105~150 cm). It is developed in elevated lava plain, and are derived from basalt, and pyroclastic materials. The typifying pedon contains 1.3~2.1% oxalate extractable (Al + 1/2 Fe), less than 85%phosphate retention, and higher bulk density than 0.90 Mg $m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 22 to 150 cm, and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol, not as Andisol. Its has 0.9% or more organic carbon in the upper 15 cm of the argillic horizon, and can be classified as Humult. It dose not have fragipan, kandic horizon, sombric horizon, plinthite, etc. in the given depths, and key out as Haplohumult. A hoizon (0~22 cm) has a fine-earth fraction with both a bulk density of 1.0 Mg $cm^{-3}$ or less, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0. Thus, it keys out as Andic Haplohumult. It has 35% or more clay at the particle-size control section, and has thermic soil temperature regime. Jeju series can be classified as fine, mixed, themic family of Andic Haplohumults, not as ashy, thermic family of Typic Hapludands. In the western, and northern coastal areas which have a relatively dry climate in Jeju Island, non Andisols are widely distributed. Mean annual precipitation increase 110 mm, and mean annual temperature decrease $0.8^{\circ}C$ with increasing elevation of 100m. In the western, and northern mid-mountaineous areas Andisols, and non Andisols are distributed simultaneously. Jeju series distributed mainly in the western and northern mid-mountaineous areas are developed as Ultisols with Andic subgroup.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.43-60
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• 1968

In order to find the effects of nitrogen type (ammonium sulfate and urea fertilizer) and fertilized depth, (0~10cm, 0cm, 5~10cm, 10~15cm, 15~20cm, and 20cm below) on leaching and absorption of nitrogen in paddy soil, and growth and yields of rice, the pot culture experiment was carried out, using the variety Jaekun, one of the Korean leading variety. Experimental results were Summarized as follows: 1. No variations of the pH of percolating water were induced by the differences of nitrogen types and their fertilized depth (Table. 2). 2. The leaching of nitrogen was less in ammonium sulfate and top soil fertilizing plots than in urea and subsoil fertilizing plot, and the growth of rice in early stage was more promoted in ammonium sulfate and topsoil fertilizing plots (Table. 1, 7 and 8). 3. Leachng of nitrogen through the percolating water almost came to an end at the most numerous tiller stage (Table 1). 4. The absorption of nitrogen of each part of the rice plant in the harvesting stage correlated closely with the yields of each part (Table 5, 6, 9 and 10) and the leaching of nitrogen in the early stage was inversely proportion to the absorption of nitrogen of rice plant in the harvesting time (Table 1, 5, 6, 9 and 10). 5. The number of spikes was more numerous in ammonium sulfate plots than in urea plots on an average, so that the yields were higher in the ammonium sulfate plots than in urea plots although no differences in the grain number per spike were found in above two plots. The number of spikes was more numerous in topsoil fertilizing plots than in subsoil fertilizing plots, but the grain number per spike was less in former than in latter, so that no difference in yields was found. The absorption of nitrogen correlated closely with the yields in complete paddy grains (Table 5, 9, and 10). 6. At the ammonium sulfate fertilizing plots, the number of spikes was more numerous in topsoil fertilizing plots than in subsoil fertilizing plots, (among the each of the topsoil plots, 0~10cm and 5~10cm fertilizing plots kept more spikes than the 0cm fertilizing plots), but the grain number per spike was less in former than in latter (among the each of topsoil plots, no differences were found), so that no significant difference in yields was showed between the topsoil and subsoil fertilizing plots, but the results showed the tendency that the yields were highest in 0~10cm plots and the lowest in 20cm below plots. At the urea fertilizing plots, the number of spikes decreased in proportion to the increasing of fertilized depth, but no variations were found in the grain number per spike, so that the yields decreased in proportion to the increasing of fertilized depth. The absorption of nitrogen correlated closely with the yields in complete paddy grains (Table 5, 6, 9, and 10). 7. When fertilized in topsoil, the number of spikes was more numerous in ammonium sulfate plot than in urea plot, but the grain number per spike variated reversely, so that no differences were found in the yields between the ammonium sulfate and the urea plots, when fertilized in subsoil, both the number of spikes and the grain number per spike were larger in ammonium sulfate than in urea plot, so that the yields were also higher in ammonium sulfate plots (Table 5, 6, 9 and 10). 8. The weight of straw and its nitrogen absorption were higher in ammonium sulfate plot than in urea plot and decreased in proportion to the increasing of fertilized depth. Among the each of topsoil fertilizing plots, the 0~10cm and the 5~10cm fertilizing plots excelled the 0cm plot (Table 5, 6, 9 and 10). 9. No significant variations in the fertilizer treatments were found in the characters of heading date, maturing date, length of culm, length of spike, weight of empty grain, 1,000 grain weight, and one liter weight.

• Korean Journal of Plant Taxonomy
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• v.40 no.3
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• pp.135-144
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• 2010

This study intended to investigate environmental factors including soil and vegetation in order to understand the environmental and ecological characteristics of four different habitats of Abelia tyaihyoni. These habitats, according to investigations, are mostly located at elevations of 203 m to 297 m with angles of inclination ranging from 9 degrees to 17 degrees. The litter depth of habitats is 2 cm to 5 cm. A total of 113 vascular plant taxa are identified in seven quadrates of the four habitats. The life form of 113 species is H-$D_4$-$R_5$-e type. The importance value of Abelia tyaihyoni is 39.61%, and 4 highly ranked species such as Quercus dentata (6.27%), Spiraea blumei, Spiraea prunifolia for. simpliciflora (4.04%) and Ulmus davidiana var. japonica (3.84%) are considered to be an affinity with Abelia tyaihyoni in their habitats. The dominant species of woody plants in the four habitats are represented as Pinus densiflora (21.22%) and Quercus dentata (16.82%) in the subtree layer (T2), and Carex humilis var. nana (18.95%) and Carex lanceolata (17.63%) in the herbaceous layer (H). The degree of their average species diversity is 1.42, and that of dominance and evenness are 0.07 and 0.86, respectively. The type of soil is sandy loam, clay loam and loam, and the average field capacity of soil is 22.49%. Their average organic matter is 9.39%, soil pH 6.75, and available phosphorus is $1.23 {\mu}g/g$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.61-67
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• 1997

This experiment was carried out from 1979 till 1983 to elucidate the underdrainage effect on soil salinity and growth of rice plastic underdrainage was established 5m and 8m intervals in April of 1979 and Jinjubyeo the medium maturing rice variety was transplanted by hand at late of May. The results are as follow; The desalination effect was higher in 5m interval underdrainage than 8m interval underdrainage and the salt content was lower than 0.3％ at 1 year after in 5m interval, 2 years after in 8m interval underdrainage and 3 years after at control. Farther the distance from underdrainage position, less the desalinization rate that desalinization was least at center part of the underdrainage position. Desalinization effect was highest 30cm of soil depth and decreased deeper than it. Shorter the underdrainage interval, more the panicle number, heavier 1, 000 grain weight and higher the milled rice yield. But the milled rice yield wasn't significantly different between the underdrainage interval from 3 years after underdrainage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.420-428
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• 1996

This study was conducted to investigate the response of growth and yield of rice under five different cultural methods, machine transplanting(MTNT), puddled drill seeding (PDSNT), drill seeding on soil surface (DSNT) , broadcasting on soil surface (BSNT) under no-tillage paddy condition and conventional machine transplanting(MTT) in Jeonbuk series(siltyloam soil) from 1993 to 1995. Soil hardness was higher in no-tillage soil and increased with highly difference between tillaged and no-tillage soil with deeper soil depth. Bulk density was heavier in no-tillage soil and porosity was higher in tilled soil than that of the control. The rate of effective tiller was higher in MTT, following MTNT, PDSNT, DSNT and BSNT. Weed occurrence was more serious in no-tillage soil, than that of tillaged soil. The rate of lower internode length was lower in DSNT and BSNT and was similar with MTT in PDSNT and MTNT. Height of center gravity in terms of lodging tolerance was lower in direct seeding than in machine transplanting. Depth of buried culm was shorter in no-tillage soil, especially in DSNT and BSNT. Total amount of root was higher in MTT, following MTNT, PDSNT, BSNT and BSNT and the distribution rate of root in shallower soil layer was higher in no-tillage soil, especially in BSNT and DSNT. Field lodging occured highly in BSNT, following DSNA, PDSNT and MTNT with high lodging scale in DSNT and BSNT. Panicle number per unit land square meter was the highest in MTT and the least in BSNT. Ripened grain ratio was low in BSNT and DSNT due to heavy lodging. Yield of milled rice was 93% in PDSNT, 87% in DSNT, 81% in BSNT and 96% in MTNT, compared with 534kg /10a in MTT.

• Korean Journal of Weed Science
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• v.18 no.3
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• pp.225-236
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• 1998

KSC-13906 [Erythro N-{(4,6-dimethoxypyrimidin-2-yl)aminocarbonyl} -2-(2-fluoro-1-hydroxy-n-propyl) benzenesulfonamide, US Patent 5,461,025] was investigated how can control phytotoxicity fluctuation and what a good method apply to new rice herbicide. The growth inhibition was observed when the rice plants was transplanted at a shallow depth(0 - 1cm) and leaching was low(0 - 1cm/ day) from the paddy soil. KSC-13906 appeared to move readily down into the paddy soil with water by 3cm depth in the soil column(${\phi}$ 10cm) filled with loamy sand soil under 3cm/day of leaching condition. Artificial control releasing pattern, designed as treated with KSC-13906 of 9 or 18g ai/ha either at a once or daily treated dividing volume of 1/20, 1/25 and 1/30 of the total volume, increased the safety of KSC-13906 to direct seeded and transplanted rice. The safety of KSC-13906 was also enhanced when KSC-13906 was mixed with dymron. For example, the mixture of KSC-13906 and dymron effectively reduced injury of direct seeded rice plants at 18 and 500g ai/ha, respectively, treated 7 days after transplanting. However, combination of KSC-13906 and several herbicides didn't show any synergistic effetct on herbicidal activity and safening effect on rice. However, the combination of KSC-13906+dymron (9~12+250~500g ai/ha) or KSC-13906+mefenacet+dymron(9+250+250g ai/ha) controlled almost all weeds in paddy field without causing any injury to rice and thus the combination would successfully be used as an oneshot herbicide in rice culture.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.39-47
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• 2002

This study was carried out in order to produce useful material for the forest multiple use and forest protection by soil physico-chemical analysis of studied area in Mt. Palgong. The results of soil physico-chemical analysis and statistical analysis represented as following 2 points. 1. Soil depth was in the range of average 61.1 cm and soil texture was loamy sand and sandy loam except Donghwasa area. The part of solid phase and gaseous phase were higher than other areas, but liquid phase was less in verse. Soil water content was in an average 49.5%, penetrability was average $1.95{\times}E^{-2}cm/sec$ and the average of soil hardness was $1.64Kg/cm^2$. This data showed that soil water content, penetrability and soil hardness were good at Mt. Palgong forest soils. 2. Soil pH was the range of 3.4 to 6.0, organic carbon content was 2.8% that is nearly mean of the Korea brown forest soils, total N content is somewhat smaller than that of other places, and total average C/N ratios was 13.9. Average available $P_2O_5$ concentration was 5.05 mg/kg that is lower than that of any others. The concentration of available P of coniferous forests is higher than that of deciduous forests. Exchangeable cations content is similar to those of the Korea brown forest soil and the order of the cation content extent is $Ca^{2+}$ > $Mg^{2+}$ > $Na^+$ > $K^+$.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.774-780
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• 2001

Aboveground carbon storage and increment of a 31-year-old pitch pine (Pinus rigida) stand were measured for five years (1997~2001) in the Jungbu Forest Experiment Station, Gyeonggi-do, Korea. The carbon concentration in each component of aboveground and soil depth decreased in the order of needle>branch>stembark>stemwood>forest floor>0-15cm soil depth>15-30cm soil depth. The carbon storage except for root carbon was 140,600kgC/ha and the tree accounted for 61%, soil 31% and forest floor 8% of the stand carbon storage. Due to high tree mortality by Fusarium subglutinans infection and spring drought in 2001, carbon increment except for 2001 data was 3,233kgC/ha/yr and was in the order of stemwood>branch>stembark>needle. Carbon storage and increment were attributed to stand density and site quality. Carbon storage and increment were higher in the high site quality than in the lower site quality plot on similar tree density. Also, the high tree density site on similar site quality showed more carbon storage and increment compared with the lower tree density. The results suggest that site quality and tree density are a key factor determining carbon storage and increment in this pitch pine stand.

• Journal of Environmental Impact Assessment
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• v.22 no.4
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• pp.303-317
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• 2013

The purpose of this study is to offer the raw data for restoration and management of trails by assessing the physical environments, the types of deterioration and the naturalness on trails located in the Sogeumgang, Hwarang and Seoak districts of Gyeongju National Park, Korea. The Sogeumgang was 5.9m, 1.1m of the Hwarang and 1.8m of the Seoak district in trail width. In the bared width of trail, the Sogeumgang was 3.9m, 0.9m of the Hwarang and 1.7m of the Seoak district. In the depth of erosion, the Sogeumgang was 37.1cm, 14.2cm of the Hwarang and Seoak district. The Sogeumgang was $16.8^{\circ}$, $13.1^{\circ}$ of the Hwarang and $12.2^{\circ}$ of the Seoak district in longitudinal slope. In the left and right of transect slope, the Sogeumgang was $18.3^{\circ}$ and $12.6^{\circ}$, $18.0^{\circ}$ and $21.3^{\circ}$ of the Hwarang and $15.3^{\circ}$ and $22.7^{\circ}$ of the Seoak district. In the left, middle and right of soil hardness, the Sogeumgang was 29.9mm, 34.7mm and 31.1mm, 27.6mm, 35.0mm and 27.2mm of the Hwarang and 27.1mm, 30.8mm and 28.0mm of the Seoak district. The types of deterioration in trails were 10 types of the Sogeumgang, 11 types of the Hwarang and 9 types of the Seoak district. The trail erosion, rock exposure and root exposure were substantially observed in the types of deterioration. In the results of the naturalness assessment, the Hwarang district was a good condition, but the Sogeumgang district was bad. The indicators of the Sogeumgang district were mostly poor.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.353-359
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• 1996

Micro plot study was conducted to elucidate the behavior of nitrogen derived from animal manure in soil and to obtain the fundamental information on animal waste management. Soils used in this experiment were sandy loam and loam. Soil water samplers (1m length ceramic cup tube) were installed at 90cm depth of soil to collect the percolate. Fresh and fermented pig manure were applied at the rate of 0, 50, 100 ton per ha. Maize was grown to evaluate the effect of crop on nitrogen behavior through soil profile. Concentration of nitrate nitrogen in percolate increased by application of pig manure. This trend was more obvious at the loam with fermented pig manure than sandy loam with fresh pig manure treatment. The concentration of nitrate nitrogen was lower under the maize cultivation than bare soil condition by 64.6-68.9%. Concentration of Ca, Mg and Na of soil and percolate increased as nitrate nitrogen concentration increased. The equivalent ratio of cation to nitrate nitrogen of percolate was increased by application of pig manure. This result showed that canon leaching was accompanied by nitrate nitrogen. Concentration of nitrate nitrogen of subsurface soil was increased by pig manure application.