• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.5
• /
• pp.348-354
• /
• 2009

We analyzed relationship soil distribution and climatic factors using temperature, precipitation and evapotranspiration maps in Jeju island. The whole area was divided into 5 groups - mesic high moisture region(group1), thermic high moisture region(group2), thermic balanced moisture region(group3), thermic short moisture region(group4), thermic very short moisture region(group5), by soil temperature and monthly moisture balances. By the sequence from group1 to group5, the occupation ratio of soils was increased in order of andisols, inceptisols, alfisols, ultisols in soil orders, and of black soils, very dark brown soils, dark brown soils in soil colors.

• Economic and Environmental Geology
• /
• v.35 no.6
• /
• pp.491-508
• /
• 2002

While about 80% of Jeju soils are classified as Andisols, the soils derived from volcanic ash in Dangsanbong are not Andisols. There is a significant difference of precipitation in localities of Jeju island. The study area is characterized by the lowest amount of annual rainfall in Jeju Island, and by the layered silicates as dominant solid phase in clay fraction. The purpose of this study was to characterize the mineralogy of the non-Andie soils in detail, especially hydroxy-interlayered silicates. Two major soil horizons are recognized in the soil profile developed in the Dangsanbong area, which can be designated as A and C. The soil pH($H_{2}0$), ranges from 6.6 to 7.3 increasing with depth, is higher than that of typical Andisols(pH<6.0). While the pH(NaF), ranges from 9.49 to 9.81, indicates that significant amount of amorphous phases might be present as exchanging complexes. It is estimated to about 1.542.88 wt% by using chemical selective dissolution. The organic content of surface horizon is about 2 wt%. This soil are composed of quartz, feldspar and olivine as major constituents with minor of silicate clays. Quartz is frequently observed in A and distinctly decreases in its amount with depth, while olivine is dominant phase in C and rarely observed in A. In the <0.2$\mu\textrm{m}$ size fraction, smectite and kaolinite/smectite interstratification are dominant with minor of illite. The amounts of smectite decrease with depth, while the amounts of kaolinite/smecite interstratification increase with depth, which indicates the trend of mineral transformation with increasing the degree of weathering. The proportion of kaolinite in kaolinite/smectite interstratification is about 85%, and is not changed significantly through the profile. In the 2-0.2$\mu\textrm{m}$size fraction, vermiculite, smectite, illite and kaolinite are major components with minor of chlorite. Most of chlorite are interstratified with smectite. Chlorite which is not interstratified with smectite occurs only in surface horizon. The proportion of the chlorite in the chlorite/smectite interstratification is 59-70(%) and increases with depth. Hydroxy-interlayered vermiculite(HIV) with hydroxy-Fe/AI in their interlayers occurs in both A and C horizon. The amounts of hydroxy-Fe/AI decrease with depth. Hydroxy-interlayered smectite(HIS) of which interlayers might be composed of hydroxy-Mg/Al occurs only in C horizon. As the results of mineralogical investigation for the soil profile in the study area, clay minerals might be changed and evolved through the following weathering sequences: 1) Smectite Kaolinite, HIS, Vermiculite, 2) Vermiculite HIV Chlorite.

• Journal of the Mineralogical Society of Korea
• /
• v.21 no.2
• /
• pp.161-175
• /
• 2008

The soil developed from volcanic ash in Jeju Island, Korea, were classified as typical Andisols. The soils had acidic pH, high water contents, high organic matters and clay-silty textures. The crystalline minerals of the samples were mainly composed of ferromagnesian minerals such as olivine and pyroxene, and iron oxides such as magnetite and hematite derived from basaltic materials. A large amount of gibbsite was found at the subsurface horizon as a secondary product from the migration of excessive aluminum. In addition, our study has shown that considerable amounts of poorly ordered minerals like allophane and ferrihydrite were present in Jeju soils. The contents of $SiO_2$ were lower than those of other soil orders, but $A1_2O_3$ and $Fe_2O_3$ contents were higher. These results are some of the important chemical properties of Andisols. The contents of heavy metals were in the range of $84{\sim}198$ for Zn, $56{\sim}414$ for Ni, $38{\sim}150$ for Co, $132{\sim}1164\;mg\;kg^{-1}$ for Cr, which are higher than the worldwide values in most of the soils. Some soil samples contained relatively high levels of Cr exceeding 1000 mg/kg. Mean reduction capacity of the Jeju soils was $6.53\;mg\;L^{-1}$ reduced Cr(VI), 5.1 times higher than that of the non-volcanic ash soils from inland of Korea. The soil reduction capacity of the inland soils had a good correlation with total carbon content (R = 0.90). However, in spite of 20 times higher total carbon contents in the Jeju soils, there was a week negative correlation between the reduction capacity and the carbon content (R = -0.469), suggesting that the reduction capacity of Jeju soils is not mainly controlled by the carbon content and affected by other soil properties. Correlations of the reduction capacity with major elements showed that Al and Fe were closely connected with the reduction capacity in Jeju soil (R = 0.793; R = 0.626 respectively). Moreover, the amounts of Ni, Co and Cr had considerable correlations with the reduction capacity (R = 0.538; R = 0.647; R = 0.468 respectively). In particular, in relation to the behavior of redox-sensitive Cr, the oxidation of the trivalent chromium to mobile and toxic hexavalent chromium can be restricted by the high reduction capacity in Jeju soil. The factors controlling the reduction capacity in Jeju soils may have a close relation with the andic soil properties explained by the presence of considerable allophane and ferrihydrite in the soils.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.3
• /
• pp.360-369
• /
• 2012

Parent material, climate, topography, biological factors, and time are considered five soil forming factors. This study was conducted to elucidate the effects of several environment factors on soil distribution using quantitative analysis method, called soil series estimation algorithm in the soils of Jeju Island. We selected environment factors including mean temperature, annual precipitation, surface geology, altitude, slope, aspect, altitude difference within 1 $km^2$ area, topographic wetness index, distance from the shore, distance from the mountain peak, and landuse for a quantitative analysis. We analyzed the ranges of environment factors for each soil series and calculated probabilities of possible-soil series for certain locations using estimation algorithm. The algorithm can predicted exact soil series on the soil map with correctness of 33% on $1^{st}$ ranking, 62% within $2^{nd}$ ranking, 74% within $5^{th}$ ranking after estimating using randomly extracted environment factors. In predicted soil map, soil sequences of Entisols-Alfisols-Andisols on northern area and Alfisols-Ultisols-Andisols on western area can be suggested along increasing altitude. More modeling studies will be needed for the genesis process of soils in Jeju Island.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.5
• /
• pp.748-754
• /
• 2010

The contents of soil organic matter (SOM) and $Al_o+1/2Fe_o$ in soils are important criteria for the classification of new Andisols in Soil Taxonomy system. There are many soil types in Jeju Island with various soil forming environments. This paper was conducted to estimate the contents of soil organic matter and the content of ammonium oxalate extracted Al and Fe ($Al_o+1/2Fe_o$) using various environmental variables and to make soil property maps using a statistical analyses. The soil samples were collected from 321 locations and analyzed to measure the contents of SOM and $Al_o+1/2Fe_o$. It was analyzed the relationships among them and various environmental variables such as temperature, precipitation, net primary product, radiation, evapotranspiration, altitude, soil forming energy, topographic wetness index, elevation, difference surrounded area, and distances from the shore and the peak. We can exclude multi-collinearity among environmental variables with principal component analysis and reduce all the variables to 3 principal components. The contents of SOM and $Al_o+1/2Fe_o$ were estimated by multiple regression models and maps of them were made using the models.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.5
• /
• pp.391-398
• /
• 2013

Soil organic carbon (SOC) has the potential to promote the soil quality for sustainability and mitigation of global warming. There is little information on organic carbon composition despite of having resistance of carbon degradation in soil. In this study, to understand the effect of volcanic ash on organic carbon composition and quantity in soil, we investigated characteristics of volcanic soil and compared organic carbon composition of soil and humic extract by using $^{13}C$-CPMAS-NMR spectra under soil profiles of Namweon series in Jeju. SOC contents of inner soil profiles were 134.8, 101.3, and 27.4 g C $kg^{-1}$ at the layer of depth 10-20, 70-80 and 90-100 cm, respectively. These layers were significantly different to soil pH, oxalate Al contents, and soil moisture contents. Alkyl C/O-alkyl C ratio in soil was higher than that of humic extracts, which was decreased below soil depth. Aromaticity of soil and humic extract was ranged from 29-38 and 24-32%, which was highest at the humic extract of 70-80 cm in soil depth. These results indicate that the changes of SOC in volcanic ash soil resulted from alteration of organic composition by pyrolysis and stability of organic carbon by allophane in volcanic ash soil.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.4
• /
• pp.497-502
• /
• 2012

This study investigates the prediction of soil OM on Korean soils using the Visible-Near Infrared (Vis-NIR) spectroscopy. The ASD Field Spec Pro was used to acquire the reflectance of soil samples to visible to near-infrared radiation (350 to 2500 nm). A total of 503 soil samples from 61 Korean soil series were scanned using the instrument and OM was measured using the Walkley and Black method. For data analysis, the spectra were resampled from 500-2450 nm with 4 nm spacing and converted to the $1^{st}$ derivative of absorbance (log (1/R)). Partial least squares regression (PLSR) and regression rules model (Cubist) were applied to predict soil OM. Regression rules model estimates the target value by building conditional rules, and each rule contains a linear expression predicting OM from selected absorbance values. The regression rules model was shown to give a better prediction compared to PLSR. Although the prediction for Andisols had a larger error, soil order was not found to be useful in stratifying the prediction model. The stratification used by Cubist was mainly based on absorbance at wavelengths of 850 and 2320 nm, which corresponds to the organic absorption bands. These results showed that there could be more information on soil properties useful to classify or group OM data from Korean soils. In conclusion, this study shows it is possible to develop good prediction model of OM from Korean soils and provide data to reexamine the existing prediction models for more accurate prediction.

• Korean Journal of Soil Science and Fertilizer
• /
• v.24 no.2
• /
• pp.86-94
• /
• 1991

Volcanic ash soils were classified as Andepts, a suborder of the Inceptisols in Soil Taxonomy. Increased knowledge on the volcanic ash soils necessitated and facilitated considerable improvement in this system. As a result, the new Order of Andisols was incorporated in the 1990 edition of the Keys to Soil Taxonomy. The central concept of an Andisol is that of a soil developing in volcanic ejecta, and/or in volcaniclastic materials, whose colloidal fractions are dominated by short-range-order minerals or Al-humus complexes. Andic propertis of volcanic ash soil in Cheju Island were investigated. For this study, soils of toposequence distributed along the southern slope of Mt. Halla, and the major soil groups such as dark brown soils, very dark brown soils, black soils, and brown forest soils were collected and analyzed for Al, Fe and Si extracted with solutions of pyrophosphate, dithionite-citrate. and oxalate respectively. Weolpyeong and Yongheung soils developed on the lower elevations contain only small amounts of allophane and Al-and Fe-humus complexes. For other soils, allophane content decrease with elevation and increaes with soil depth,whereas Al-humus complexes increase with elevation and decrease with soil depth. Substantial amount of allophane and ferrihydrite are found in all horizons of Ora and Ara soils developed on 150-300m elevations and of Noro and Jeogag soils developed on cinder cones. In the A horizons of Pyeongdae, Tosan and Heugag soils developed on the higher elevations, Al-humus complexes are dominant form of Al reflecting low pH and high organic matter content. However, lower horizons are dominated by allophane.

• Korean Journal of Soil Science and Fertilizer
• /
• v.41 no.3
• /
• pp.199-205
• /
• 2008

This study was carried out to find out causes of high Ni content and characteristics of potential increase of Cu and Zn contents in the soils of Jeju area. Soil samples were collected from 4 series of Alfisols, 35 series of Andisols, 9 series of Entisols, 16 series of Inceptisols, and 1 series of Ultisols, respectively. Parent material (gravel) samples were also collected from the same sites where soil samples were taken. Both soil and parent material samples were analyzed for Ni, Cu, and Zn. The average Ni content of all the soil samples was $79.2mg\;kg^{-1}$, which was exceeded warning standard for Ni against the Soil Conservation Act in Korea, whereas that of Cu and Zn contents were lower than the warning standard for Cu and Zn. The difference of Ni, Cu and Zn content was not consistent depending upon soil color. Ni content in the soil samples from Entisols was particularly high, whereas that from the other soil orders was similar to each other. Cu and Zn contents in the soil samples were similar regardless of the difference in soil order. Ni content in Seongsan Formation(SSF), Cinder cone(C) and acicular Feldspar Olivine Basalt(FOB) was high, while that in Feldspar Basalt(FB) and Trachy Andesite lava(TA) was low. Ni content in the non-agricultural land was higher compared with that in the agricultural land, whereas Cu and Zn contents in the non-agricultural land were significantly lower than that of agricultural land. The topsoil/subsoil ratios for Ni content in most of the soil samples were less than 1, while that for total contents of Cu and Zn in many of the soil samples were larger than 1 indicating potential Cu and Zn accumulation in topsoil by artificial reasons.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.2
• /
• pp.88-97
• /
• 2009

This study was conducted to obtain the basic information to increase the practical use of soil survey data through the subdividing of lava shapes with soil sequences due to different elevations in Jeju. The numbers of soil series of lava topography had occupied many of whole soil series in Jeju. When its topography subdivide, it give more detailed soil information. The obtained results are as follows; The lava topography to subdivide lava topography were studied with 38 soil series according to elevation in Jeju. Division of elevation are less than 50m, 50m to 200m, and 200m to 400m and more than 400m. Name the depending on elevation, less than 50m is called lower part of lava, 50m to 200m is called middle part of lava, and 200m to 400m and more than 400m are called upper part of lava. The characteristics of lava subdivide are as follows; soil family texture of lower part of lava is fine silty to clayey, drainage classes are various, average of available soil depth is 75.3cm, average of gravely contents are 11.6%, average of slopeness is 7.2%, limiting factor are various and soil order are various. soil family texture of middle part of lava is fine silty to coarse silty, drainage classes are well to very well, average of available soil depth is 65.9cm, average of gravely contents are 14.7%, average of slopeness is 11.3%, limiting factor are ashy and soil order are Andisols and Inceptisols. Soil family texture of upper part of lave is fine silty, drainage classes are well, average of available soil depth is 72.8cm, average of gravely contents are 16.0%, average of slopeness is 14.9%, limiting factor are ashy and skeletal, and order are Andisols.